| /* |
| * Base port operations for 8250/16550-type serial ports |
| * |
| * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o. |
| * Split from 8250_core.c, Copyright (C) 2001 Russell King. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * A note about mapbase / membase |
| * |
| * mapbase is the physical address of the IO port. |
| * membase is an 'ioremapped' cookie. |
| */ |
| |
| #if defined(CONFIG_SERIAL_8250_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) |
| #define SUPPORT_SYSRQ |
| #endif |
| |
| #include <linux/module.h> |
| #include <linux/moduleparam.h> |
| #include <linux/ioport.h> |
| #include <linux/init.h> |
| #include <linux/console.h> |
| #include <linux/sysrq.h> |
| #include <linux/delay.h> |
| #include <linux/platform_device.h> |
| #include <linux/tty.h> |
| #include <linux/ratelimit.h> |
| #include <linux/tty_flip.h> |
| #include <linux/serial.h> |
| #include <linux/serial_8250.h> |
| #include <linux/nmi.h> |
| #include <linux/mutex.h> |
| #include <linux/slab.h> |
| #include <linux/uaccess.h> |
| #include <linux/pm_runtime.h> |
| #include <linux/timer.h> |
| |
| #include <asm/io.h> |
| #include <asm/irq.h> |
| |
| #include "8250.h" |
| |
| /* |
| * Debugging. |
| */ |
| #if 0 |
| #define DEBUG_AUTOCONF(fmt...) printk(fmt) |
| #else |
| #define DEBUG_AUTOCONF(fmt...) do { } while (0) |
| #endif |
| |
| #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE) |
| |
| /* |
| * Here we define the default xmit fifo size used for each type of UART. |
| */ |
| static const struct serial8250_config uart_config[] = { |
| [PORT_UNKNOWN] = { |
| .name = "unknown", |
| .fifo_size = 1, |
| .tx_loadsz = 1, |
| }, |
| [PORT_8250] = { |
| .name = "8250", |
| .fifo_size = 1, |
| .tx_loadsz = 1, |
| }, |
| [PORT_16450] = { |
| .name = "16450", |
| .fifo_size = 1, |
| .tx_loadsz = 1, |
| }, |
| [PORT_16550] = { |
| .name = "16550", |
| .fifo_size = 1, |
| .tx_loadsz = 1, |
| }, |
| [PORT_16550A] = { |
| .name = "16550A", |
| .fifo_size = 16, |
| .tx_loadsz = 16, |
| .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10 | |
| UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT, |
| .rxtrig_bytes = {1, 4, 8, 14}, |
| .flags = UART_CAP_FIFO, |
| }, |
| [PORT_CIRRUS] = { |
| .name = "Cirrus", |
| .fifo_size = 1, |
| .tx_loadsz = 1, |
| }, |
| [PORT_16650] = { |
| .name = "ST16650", |
| .fifo_size = 1, |
| .tx_loadsz = 1, |
| .flags = UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP, |
| }, |
| [PORT_16650V2] = { |
| .name = "ST16650V2", |
| .fifo_size = 32, |
| .tx_loadsz = 16, |
| .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 | |
| UART_FCR_T_TRIG_00, |
| .rxtrig_bytes = {8, 16, 24, 28}, |
| .flags = UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP, |
| }, |
| [PORT_16750] = { |
| .name = "TI16750", |
| .fifo_size = 64, |
| .tx_loadsz = 64, |
| .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10 | |
| UART_FCR7_64BYTE, |
| .rxtrig_bytes = {1, 16, 32, 56}, |
| .flags = UART_CAP_FIFO | UART_CAP_SLEEP | UART_CAP_AFE, |
| }, |
| [PORT_STARTECH] = { |
| .name = "Startech", |
| .fifo_size = 1, |
| .tx_loadsz = 1, |
| }, |
| [PORT_16C950] = { |
| .name = "16C950/954", |
| .fifo_size = 128, |
| .tx_loadsz = 128, |
| .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, |
| /* UART_CAP_EFR breaks billionon CF bluetooth card. */ |
| .flags = UART_CAP_FIFO | UART_CAP_SLEEP, |
| }, |
| [PORT_16654] = { |
| .name = "ST16654", |
| .fifo_size = 64, |
| .tx_loadsz = 32, |
| .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 | |
| UART_FCR_T_TRIG_10, |
| .rxtrig_bytes = {8, 16, 56, 60}, |
| .flags = UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP, |
| }, |
| [PORT_16850] = { |
| .name = "XR16850", |
| .fifo_size = 128, |
| .tx_loadsz = 128, |
| .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, |
| .flags = UART_CAP_FIFO | UART_CAP_EFR | UART_CAP_SLEEP, |
| }, |
| [PORT_RSA] = { |
| .name = "RSA", |
| .fifo_size = 2048, |
| .tx_loadsz = 2048, |
| .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_11, |
| .flags = UART_CAP_FIFO, |
| }, |
| [PORT_NS16550A] = { |
| .name = "NS16550A", |
| .fifo_size = 16, |
| .tx_loadsz = 16, |
| .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, |
| .flags = UART_CAP_FIFO | UART_NATSEMI, |
| }, |
| [PORT_XSCALE] = { |
| .name = "XScale", |
| .fifo_size = 32, |
| .tx_loadsz = 32, |
| .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, |
| .flags = UART_CAP_FIFO | UART_CAP_UUE | UART_CAP_RTOIE, |
| }, |
| [PORT_OCTEON] = { |
| .name = "OCTEON", |
| .fifo_size = 64, |
| .tx_loadsz = 64, |
| .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, |
| .flags = UART_CAP_FIFO, |
| }, |
| [PORT_AR7] = { |
| .name = "AR7", |
| .fifo_size = 16, |
| .tx_loadsz = 16, |
| .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_00, |
| .flags = UART_CAP_FIFO /* | UART_CAP_AFE */, |
| }, |
| [PORT_U6_16550A] = { |
| .name = "U6_16550A", |
| .fifo_size = 64, |
| .tx_loadsz = 64, |
| .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, |
| .flags = UART_CAP_FIFO | UART_CAP_AFE, |
| }, |
| [PORT_TEGRA] = { |
| .name = "Tegra", |
| .fifo_size = 32, |
| .tx_loadsz = 8, |
| .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 | |
| UART_FCR_T_TRIG_01, |
| .rxtrig_bytes = {1, 4, 8, 14}, |
| .flags = UART_CAP_FIFO | UART_CAP_RTOIE, |
| }, |
| [PORT_XR17D15X] = { |
| .name = "XR17D15X", |
| .fifo_size = 64, |
| .tx_loadsz = 64, |
| .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, |
| .flags = UART_CAP_FIFO | UART_CAP_AFE | UART_CAP_EFR | |
| UART_CAP_SLEEP, |
| }, |
| [PORT_XR17V35X] = { |
| .name = "XR17V35X", |
| .fifo_size = 256, |
| .tx_loadsz = 256, |
| .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_11 | |
| UART_FCR_T_TRIG_11, |
| .flags = UART_CAP_FIFO | UART_CAP_AFE | UART_CAP_EFR | |
| UART_CAP_SLEEP, |
| }, |
| [PORT_LPC3220] = { |
| .name = "LPC3220", |
| .fifo_size = 64, |
| .tx_loadsz = 32, |
| .fcr = UART_FCR_DMA_SELECT | UART_FCR_ENABLE_FIFO | |
| UART_FCR_R_TRIG_00 | UART_FCR_T_TRIG_00, |
| .flags = UART_CAP_FIFO, |
| }, |
| [PORT_BRCM_TRUMANAGE] = { |
| .name = "TruManage", |
| .fifo_size = 1, |
| .tx_loadsz = 1024, |
| .flags = UART_CAP_HFIFO, |
| }, |
| [PORT_8250_CIR] = { |
| .name = "CIR port" |
| }, |
| [PORT_ALTR_16550_F32] = { |
| .name = "Altera 16550 FIFO32", |
| .fifo_size = 32, |
| .tx_loadsz = 32, |
| .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, |
| .flags = UART_CAP_FIFO | UART_CAP_AFE, |
| }, |
| [PORT_ALTR_16550_F64] = { |
| .name = "Altera 16550 FIFO64", |
| .fifo_size = 64, |
| .tx_loadsz = 64, |
| .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, |
| .flags = UART_CAP_FIFO | UART_CAP_AFE, |
| }, |
| [PORT_ALTR_16550_F128] = { |
| .name = "Altera 16550 FIFO128", |
| .fifo_size = 128, |
| .tx_loadsz = 128, |
| .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, |
| .flags = UART_CAP_FIFO | UART_CAP_AFE, |
| }, |
| /* |
| * tx_loadsz is set to 63-bytes instead of 64-bytes to implement |
| * workaround of errata A-008006 which states that tx_loadsz should |
| * be configured less than Maximum supported fifo bytes. |
| */ |
| [PORT_16550A_FSL64] = { |
| .name = "16550A_FSL64", |
| .fifo_size = 64, |
| .tx_loadsz = 63, |
| .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10 | |
| UART_FCR7_64BYTE, |
| .flags = UART_CAP_FIFO, |
| }, |
| [PORT_RT2880] = { |
| .name = "Palmchip BK-3103", |
| .fifo_size = 16, |
| .tx_loadsz = 16, |
| .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, |
| .rxtrig_bytes = {1, 4, 8, 14}, |
| .flags = UART_CAP_FIFO, |
| }, |
| }; |
| |
| /* Uart divisor latch read */ |
| static int default_serial_dl_read(struct uart_8250_port *up) |
| { |
| return serial_in(up, UART_DLL) | serial_in(up, UART_DLM) << 8; |
| } |
| |
| /* Uart divisor latch write */ |
| static void default_serial_dl_write(struct uart_8250_port *up, int value) |
| { |
| serial_out(up, UART_DLL, value & 0xff); |
| serial_out(up, UART_DLM, value >> 8 & 0xff); |
| } |
| |
| #ifdef CONFIG_SERIAL_8250_RT288X |
| |
| /* Au1x00/RT288x UART hardware has a weird register layout */ |
| static const s8 au_io_in_map[8] = { |
| 0, /* UART_RX */ |
| 2, /* UART_IER */ |
| 3, /* UART_IIR */ |
| 5, /* UART_LCR */ |
| 6, /* UART_MCR */ |
| 7, /* UART_LSR */ |
| 8, /* UART_MSR */ |
| -1, /* UART_SCR (unmapped) */ |
| }; |
| |
| static const s8 au_io_out_map[8] = { |
| 1, /* UART_TX */ |
| 2, /* UART_IER */ |
| 4, /* UART_FCR */ |
| 5, /* UART_LCR */ |
| 6, /* UART_MCR */ |
| -1, /* UART_LSR (unmapped) */ |
| -1, /* UART_MSR (unmapped) */ |
| -1, /* UART_SCR (unmapped) */ |
| }; |
| |
| static unsigned int au_serial_in(struct uart_port *p, int offset) |
| { |
| if (offset >= ARRAY_SIZE(au_io_in_map)) |
| return UINT_MAX; |
| offset = au_io_in_map[offset]; |
| if (offset < 0) |
| return UINT_MAX; |
| return __raw_readl(p->membase + (offset << p->regshift)); |
| } |
| |
| static void au_serial_out(struct uart_port *p, int offset, int value) |
| { |
| if (offset >= ARRAY_SIZE(au_io_out_map)) |
| return; |
| offset = au_io_out_map[offset]; |
| if (offset < 0) |
| return; |
| __raw_writel(value, p->membase + (offset << p->regshift)); |
| } |
| |
| /* Au1x00 haven't got a standard divisor latch */ |
| static int au_serial_dl_read(struct uart_8250_port *up) |
| { |
| return __raw_readl(up->port.membase + 0x28); |
| } |
| |
| static void au_serial_dl_write(struct uart_8250_port *up, int value) |
| { |
| __raw_writel(value, up->port.membase + 0x28); |
| } |
| |
| #endif |
| |
| static unsigned int hub6_serial_in(struct uart_port *p, int offset) |
| { |
| offset = offset << p->regshift; |
| outb(p->hub6 - 1 + offset, p->iobase); |
| return inb(p->iobase + 1); |
| } |
| |
| static void hub6_serial_out(struct uart_port *p, int offset, int value) |
| { |
| offset = offset << p->regshift; |
| outb(p->hub6 - 1 + offset, p->iobase); |
| outb(value, p->iobase + 1); |
| } |
| |
| static unsigned int mem_serial_in(struct uart_port *p, int offset) |
| { |
| offset = offset << p->regshift; |
| return readb(p->membase + offset); |
| } |
| |
| static void mem_serial_out(struct uart_port *p, int offset, int value) |
| { |
| offset = offset << p->regshift; |
| writeb(value, p->membase + offset); |
| } |
| |
| static void mem16_serial_out(struct uart_port *p, int offset, int value) |
| { |
| offset = offset << p->regshift; |
| writew(value, p->membase + offset); |
| } |
| |
| static unsigned int mem16_serial_in(struct uart_port *p, int offset) |
| { |
| offset = offset << p->regshift; |
| return readw(p->membase + offset); |
| } |
| |
| static void mem32_serial_out(struct uart_port *p, int offset, int value) |
| { |
| offset = offset << p->regshift; |
| writel(value, p->membase + offset); |
| } |
| |
| static unsigned int mem32_serial_in(struct uart_port *p, int offset) |
| { |
| offset = offset << p->regshift; |
| return readl(p->membase + offset); |
| } |
| |
| static void mem32be_serial_out(struct uart_port *p, int offset, int value) |
| { |
| offset = offset << p->regshift; |
| iowrite32be(value, p->membase + offset); |
| } |
| |
| static unsigned int mem32be_serial_in(struct uart_port *p, int offset) |
| { |
| offset = offset << p->regshift; |
| return ioread32be(p->membase + offset); |
| } |
| |
| static unsigned int io_serial_in(struct uart_port *p, int offset) |
| { |
| offset = offset << p->regshift; |
| return inb(p->iobase + offset); |
| } |
| |
| static void io_serial_out(struct uart_port *p, int offset, int value) |
| { |
| offset = offset << p->regshift; |
| outb(value, p->iobase + offset); |
| } |
| |
| static int serial8250_default_handle_irq(struct uart_port *port); |
| static int exar_handle_irq(struct uart_port *port); |
| |
| static void set_io_from_upio(struct uart_port *p) |
| { |
| struct uart_8250_port *up = up_to_u8250p(p); |
| |
| up->dl_read = default_serial_dl_read; |
| up->dl_write = default_serial_dl_write; |
| |
| switch (p->iotype) { |
| case UPIO_HUB6: |
| p->serial_in = hub6_serial_in; |
| p->serial_out = hub6_serial_out; |
| break; |
| |
| case UPIO_MEM: |
| p->serial_in = mem_serial_in; |
| p->serial_out = mem_serial_out; |
| break; |
| |
| case UPIO_MEM16: |
| p->serial_in = mem16_serial_in; |
| p->serial_out = mem16_serial_out; |
| break; |
| |
| case UPIO_MEM32: |
| p->serial_in = mem32_serial_in; |
| p->serial_out = mem32_serial_out; |
| break; |
| |
| case UPIO_MEM32BE: |
| p->serial_in = mem32be_serial_in; |
| p->serial_out = mem32be_serial_out; |
| break; |
| |
| #ifdef CONFIG_SERIAL_8250_RT288X |
| case UPIO_AU: |
| p->serial_in = au_serial_in; |
| p->serial_out = au_serial_out; |
| up->dl_read = au_serial_dl_read; |
| up->dl_write = au_serial_dl_write; |
| break; |
| #endif |
| |
| default: |
| p->serial_in = io_serial_in; |
| p->serial_out = io_serial_out; |
| break; |
| } |
| /* Remember loaded iotype */ |
| up->cur_iotype = p->iotype; |
| p->handle_irq = serial8250_default_handle_irq; |
| } |
| |
| static void |
| serial_port_out_sync(struct uart_port *p, int offset, int value) |
| { |
| switch (p->iotype) { |
| case UPIO_MEM: |
| case UPIO_MEM16: |
| case UPIO_MEM32: |
| case UPIO_MEM32BE: |
| case UPIO_AU: |
| p->serial_out(p, offset, value); |
| p->serial_in(p, UART_LCR); /* safe, no side-effects */ |
| break; |
| default: |
| p->serial_out(p, offset, value); |
| } |
| } |
| |
| /* |
| * For the 16C950 |
| */ |
| static void serial_icr_write(struct uart_8250_port *up, int offset, int value) |
| { |
| serial_out(up, UART_SCR, offset); |
| serial_out(up, UART_ICR, value); |
| } |
| |
| static unsigned int serial_icr_read(struct uart_8250_port *up, int offset) |
| { |
| unsigned int value; |
| |
| serial_icr_write(up, UART_ACR, up->acr | UART_ACR_ICRRD); |
| serial_out(up, UART_SCR, offset); |
| value = serial_in(up, UART_ICR); |
| serial_icr_write(up, UART_ACR, up->acr); |
| |
| return value; |
| } |
| |
| /* |
| * FIFO support. |
| */ |
| static void serial8250_clear_fifos(struct uart_8250_port *p) |
| { |
| if (p->capabilities & UART_CAP_FIFO) { |
| serial_out(p, UART_FCR, UART_FCR_ENABLE_FIFO); |
| serial_out(p, UART_FCR, UART_FCR_ENABLE_FIFO | |
| UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); |
| serial_out(p, UART_FCR, 0); |
| } |
| } |
| |
| static inline void serial8250_em485_rts_after_send(struct uart_8250_port *p) |
| { |
| unsigned char mcr = serial8250_in_MCR(p); |
| |
| if (p->port.rs485.flags & SER_RS485_RTS_AFTER_SEND) |
| mcr |= UART_MCR_RTS; |
| else |
| mcr &= ~UART_MCR_RTS; |
| serial8250_out_MCR(p, mcr); |
| } |
| |
| static void serial8250_em485_handle_start_tx(unsigned long arg); |
| static void serial8250_em485_handle_stop_tx(unsigned long arg); |
| |
| void serial8250_clear_and_reinit_fifos(struct uart_8250_port *p) |
| { |
| serial8250_clear_fifos(p); |
| serial_out(p, UART_FCR, p->fcr); |
| } |
| EXPORT_SYMBOL_GPL(serial8250_clear_and_reinit_fifos); |
| |
| void serial8250_rpm_get(struct uart_8250_port *p) |
| { |
| if (!(p->capabilities & UART_CAP_RPM)) |
| return; |
| pm_runtime_get_sync(p->port.dev); |
| } |
| EXPORT_SYMBOL_GPL(serial8250_rpm_get); |
| |
| void serial8250_rpm_put(struct uart_8250_port *p) |
| { |
| if (!(p->capabilities & UART_CAP_RPM)) |
| return; |
| pm_runtime_mark_last_busy(p->port.dev); |
| pm_runtime_put_autosuspend(p->port.dev); |
| } |
| EXPORT_SYMBOL_GPL(serial8250_rpm_put); |
| |
| /** |
| * serial8250_em485_init() - put uart_8250_port into rs485 emulating |
| * @p: uart_8250_port port instance |
| * |
| * The function is used to start rs485 software emulating on the |
| * &struct uart_8250_port* @p. Namely, RTS is switched before/after |
| * transmission. The function is idempotent, so it is safe to call it |
| * multiple times. |
| * |
| * The caller MUST enable interrupt on empty shift register before |
| * calling serial8250_em485_init(). This interrupt is not a part of |
| * 8250 standard, but implementation defined. |
| * |
| * The function is supposed to be called from .rs485_config callback |
| * or from any other callback protected with p->port.lock spinlock. |
| * |
| * See also serial8250_em485_destroy() |
| * |
| * Return 0 - success, -errno - otherwise |
| */ |
| int serial8250_em485_init(struct uart_8250_port *p) |
| { |
| if (p->em485) |
| return 0; |
| |
| p->em485 = kmalloc(sizeof(struct uart_8250_em485), GFP_ATOMIC); |
| if (!p->em485) |
| return -ENOMEM; |
| |
| setup_timer(&p->em485->stop_tx_timer, |
| serial8250_em485_handle_stop_tx, (unsigned long)p); |
| setup_timer(&p->em485->start_tx_timer, |
| serial8250_em485_handle_start_tx, (unsigned long)p); |
| p->em485->active_timer = NULL; |
| |
| serial8250_em485_rts_after_send(p); |
| |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(serial8250_em485_init); |
| |
| /** |
| * serial8250_em485_destroy() - put uart_8250_port into normal state |
| * @p: uart_8250_port port instance |
| * |
| * The function is used to stop rs485 software emulating on the |
| * &struct uart_8250_port* @p. The function is idempotent, so it is safe to |
| * call it multiple times. |
| * |
| * The function is supposed to be called from .rs485_config callback |
| * or from any other callback protected with p->port.lock spinlock. |
| * |
| * See also serial8250_em485_init() |
| */ |
| void serial8250_em485_destroy(struct uart_8250_port *p) |
| { |
| if (!p->em485) |
| return; |
| |
| del_timer(&p->em485->start_tx_timer); |
| del_timer(&p->em485->stop_tx_timer); |
| |
| kfree(p->em485); |
| p->em485 = NULL; |
| } |
| EXPORT_SYMBOL_GPL(serial8250_em485_destroy); |
| |
| /* |
| * These two wrappers ensure that enable_runtime_pm_tx() can be called more than |
| * once and disable_runtime_pm_tx() will still disable RPM because the fifo is |
| * empty and the HW can idle again. |
| */ |
| void serial8250_rpm_get_tx(struct uart_8250_port *p) |
| { |
| unsigned char rpm_active; |
| |
| if (!(p->capabilities & UART_CAP_RPM)) |
| return; |
| |
| rpm_active = xchg(&p->rpm_tx_active, 1); |
| if (rpm_active) |
| return; |
| pm_runtime_get_sync(p->port.dev); |
| } |
| EXPORT_SYMBOL_GPL(serial8250_rpm_get_tx); |
| |
| void serial8250_rpm_put_tx(struct uart_8250_port *p) |
| { |
| unsigned char rpm_active; |
| |
| if (!(p->capabilities & UART_CAP_RPM)) |
| return; |
| |
| rpm_active = xchg(&p->rpm_tx_active, 0); |
| if (!rpm_active) |
| return; |
| pm_runtime_mark_last_busy(p->port.dev); |
| pm_runtime_put_autosuspend(p->port.dev); |
| } |
| EXPORT_SYMBOL_GPL(serial8250_rpm_put_tx); |
| |
| /* |
| * IER sleep support. UARTs which have EFRs need the "extended |
| * capability" bit enabled. Note that on XR16C850s, we need to |
| * reset LCR to write to IER. |
| */ |
| static void serial8250_set_sleep(struct uart_8250_port *p, int sleep) |
| { |
| unsigned char lcr = 0, efr = 0; |
| /* |
| * Exar UARTs have a SLEEP register that enables or disables |
| * each UART to enter sleep mode separately. On the XR17V35x the |
| * register is accessible to each UART at the UART_EXAR_SLEEP |
| * offset but the UART channel may only write to the corresponding |
| * bit. |
| */ |
| serial8250_rpm_get(p); |
| if ((p->port.type == PORT_XR17V35X) || |
| (p->port.type == PORT_XR17D15X)) { |
| serial_out(p, UART_EXAR_SLEEP, sleep ? 0xff : 0); |
| goto out; |
| } |
| |
| if (p->capabilities & UART_CAP_SLEEP) { |
| if (p->capabilities & UART_CAP_EFR) { |
| lcr = serial_in(p, UART_LCR); |
| efr = serial_in(p, UART_EFR); |
| serial_out(p, UART_LCR, UART_LCR_CONF_MODE_B); |
| serial_out(p, UART_EFR, UART_EFR_ECB); |
| serial_out(p, UART_LCR, 0); |
| } |
| serial_out(p, UART_IER, sleep ? UART_IERX_SLEEP : 0); |
| if (p->capabilities & UART_CAP_EFR) { |
| serial_out(p, UART_LCR, UART_LCR_CONF_MODE_B); |
| serial_out(p, UART_EFR, efr); |
| serial_out(p, UART_LCR, lcr); |
| } |
| } |
| out: |
| serial8250_rpm_put(p); |
| } |
| |
| #ifdef CONFIG_SERIAL_8250_RSA |
| /* |
| * Attempts to turn on the RSA FIFO. Returns zero on failure. |
| * We set the port uart clock rate if we succeed. |
| */ |
| static int __enable_rsa(struct uart_8250_port *up) |
| { |
| unsigned char mode; |
| int result; |
| |
| mode = serial_in(up, UART_RSA_MSR); |
| result = mode & UART_RSA_MSR_FIFO; |
| |
| if (!result) { |
| serial_out(up, UART_RSA_MSR, mode | UART_RSA_MSR_FIFO); |
| mode = serial_in(up, UART_RSA_MSR); |
| result = mode & UART_RSA_MSR_FIFO; |
| } |
| |
| if (result) |
| up->port.uartclk = SERIAL_RSA_BAUD_BASE * 16; |
| |
| return result; |
| } |
| |
| static void enable_rsa(struct uart_8250_port *up) |
| { |
| if (up->port.type == PORT_RSA) { |
| if (up->port.uartclk != SERIAL_RSA_BAUD_BASE * 16) { |
| spin_lock_irq(&up->port.lock); |
| __enable_rsa(up); |
| spin_unlock_irq(&up->port.lock); |
| } |
| if (up->port.uartclk == SERIAL_RSA_BAUD_BASE * 16) |
| serial_out(up, UART_RSA_FRR, 0); |
| } |
| } |
| |
| /* |
| * Attempts to turn off the RSA FIFO. Returns zero on failure. |
| * It is unknown why interrupts were disabled in here. However, |
| * the caller is expected to preserve this behaviour by grabbing |
| * the spinlock before calling this function. |
| */ |
| static void disable_rsa(struct uart_8250_port *up) |
| { |
| unsigned char mode; |
| int result; |
| |
| if (up->port.type == PORT_RSA && |
| up->port.uartclk == SERIAL_RSA_BAUD_BASE * 16) { |
| spin_lock_irq(&up->port.lock); |
| |
| mode = serial_in(up, UART_RSA_MSR); |
| result = !(mode & UART_RSA_MSR_FIFO); |
| |
| if (!result) { |
| serial_out(up, UART_RSA_MSR, mode & ~UART_RSA_MSR_FIFO); |
| mode = serial_in(up, UART_RSA_MSR); |
| result = !(mode & UART_RSA_MSR_FIFO); |
| } |
| |
| if (result) |
| up->port.uartclk = SERIAL_RSA_BAUD_BASE_LO * 16; |
| spin_unlock_irq(&up->port.lock); |
| } |
| } |
| #endif /* CONFIG_SERIAL_8250_RSA */ |
| |
| /* |
| * This is a quickie test to see how big the FIFO is. |
| * It doesn't work at all the time, more's the pity. |
| */ |
| static int size_fifo(struct uart_8250_port *up) |
| { |
| unsigned char old_fcr, old_mcr, old_lcr; |
| unsigned short old_dl; |
| int count; |
| |
| old_lcr = serial_in(up, UART_LCR); |
| serial_out(up, UART_LCR, 0); |
| old_fcr = serial_in(up, UART_FCR); |
| old_mcr = serial8250_in_MCR(up); |
| serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | |
| UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); |
| serial8250_out_MCR(up, UART_MCR_LOOP); |
| serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A); |
| old_dl = serial_dl_read(up); |
| serial_dl_write(up, 0x0001); |
| serial_out(up, UART_LCR, 0x03); |
| for (count = 0; count < 256; count++) |
| serial_out(up, UART_TX, count); |
| mdelay(20);/* FIXME - schedule_timeout */ |
| for (count = 0; (serial_in(up, UART_LSR) & UART_LSR_DR) && |
| (count < 256); count++) |
| serial_in(up, UART_RX); |
| serial_out(up, UART_FCR, old_fcr); |
| serial8250_out_MCR(up, old_mcr); |
| serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A); |
| serial_dl_write(up, old_dl); |
| serial_out(up, UART_LCR, old_lcr); |
| |
| return count; |
| } |
| |
| /* |
| * Read UART ID using the divisor method - set DLL and DLM to zero |
| * and the revision will be in DLL and device type in DLM. We |
| * preserve the device state across this. |
| */ |
| static unsigned int autoconfig_read_divisor_id(struct uart_8250_port *p) |
| { |
| unsigned char old_lcr; |
| unsigned int id, old_dl; |
| |
| old_lcr = serial_in(p, UART_LCR); |
| serial_out(p, UART_LCR, UART_LCR_CONF_MODE_A); |
| old_dl = serial_dl_read(p); |
| serial_dl_write(p, 0); |
| id = serial_dl_read(p); |
| serial_dl_write(p, old_dl); |
| |
| serial_out(p, UART_LCR, old_lcr); |
| |
| return id; |
| } |
| |
| /* |
| * This is a helper routine to autodetect StarTech/Exar/Oxsemi UART's. |
| * When this function is called we know it is at least a StarTech |
| * 16650 V2, but it might be one of several StarTech UARTs, or one of |
| * its clones. (We treat the broken original StarTech 16650 V1 as a |
| * 16550, and why not? Startech doesn't seem to even acknowledge its |
| * existence.) |
| * |
| * What evil have men's minds wrought... |
| */ |
| static void autoconfig_has_efr(struct uart_8250_port *up) |
| { |
| unsigned int id1, id2, id3, rev; |
| |
| /* |
| * Everything with an EFR has SLEEP |
| */ |
| up->capabilities |= UART_CAP_EFR | UART_CAP_SLEEP; |
| |
| /* |
| * First we check to see if it's an Oxford Semiconductor UART. |
| * |
| * If we have to do this here because some non-National |
| * Semiconductor clone chips lock up if you try writing to the |
| * LSR register (which serial_icr_read does) |
| */ |
| |
| /* |
| * Check for Oxford Semiconductor 16C950. |
| * |
| * EFR [4] must be set else this test fails. |
| * |
| * This shouldn't be necessary, but Mike Hudson (Exoray@isys.ca) |
| * claims that it's needed for 952 dual UART's (which are not |
| * recommended for new designs). |
| */ |
| up->acr = 0; |
| serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); |
| serial_out(up, UART_EFR, UART_EFR_ECB); |
| serial_out(up, UART_LCR, 0x00); |
| id1 = serial_icr_read(up, UART_ID1); |
| id2 = serial_icr_read(up, UART_ID2); |
| id3 = serial_icr_read(up, UART_ID3); |
| rev = serial_icr_read(up, UART_REV); |
| |
| DEBUG_AUTOCONF("950id=%02x:%02x:%02x:%02x ", id1, id2, id3, rev); |
| |
| if (id1 == 0x16 && id2 == 0xC9 && |
| (id3 == 0x50 || id3 == 0x52 || id3 == 0x54)) { |
| up->port.type = PORT_16C950; |
| |
| /* |
| * Enable work around for the Oxford Semiconductor 952 rev B |
| * chip which causes it to seriously miscalculate baud rates |
| * when DLL is 0. |
| */ |
| if (id3 == 0x52 && rev == 0x01) |
| up->bugs |= UART_BUG_QUOT; |
| return; |
| } |
| |
| /* |
| * We check for a XR16C850 by setting DLL and DLM to 0, and then |
| * reading back DLL and DLM. The chip type depends on the DLM |
| * value read back: |
| * 0x10 - XR16C850 and the DLL contains the chip revision. |
| * 0x12 - XR16C2850. |
| * 0x14 - XR16C854. |
| */ |
| id1 = autoconfig_read_divisor_id(up); |
| DEBUG_AUTOCONF("850id=%04x ", id1); |
| |
| id2 = id1 >> 8; |
| if (id2 == 0x10 || id2 == 0x12 || id2 == 0x14) { |
| up->port.type = PORT_16850; |
| return; |
| } |
| |
| /* |
| * It wasn't an XR16C850. |
| * |
| * We distinguish between the '654 and the '650 by counting |
| * how many bytes are in the FIFO. I'm using this for now, |
| * since that's the technique that was sent to me in the |
| * serial driver update, but I'm not convinced this works. |
| * I've had problems doing this in the past. -TYT |
| */ |
| if (size_fifo(up) == 64) |
| up->port.type = PORT_16654; |
| else |
| up->port.type = PORT_16650V2; |
| } |
| |
| /* |
| * We detected a chip without a FIFO. Only two fall into |
| * this category - the original 8250 and the 16450. The |
| * 16450 has a scratch register (accessible with LCR=0) |
| */ |
| static void autoconfig_8250(struct uart_8250_port *up) |
| { |
| unsigned char scratch, status1, status2; |
| |
| up->port.type = PORT_8250; |
| |
| scratch = serial_in(up, UART_SCR); |
| serial_out(up, UART_SCR, 0xa5); |
| status1 = serial_in(up, UART_SCR); |
| serial_out(up, UART_SCR, 0x5a); |
| status2 = serial_in(up, UART_SCR); |
| serial_out(up, UART_SCR, scratch); |
| |
| if (status1 == 0xa5 && status2 == 0x5a) |
| up->port.type = PORT_16450; |
| } |
| |
| static int broken_efr(struct uart_8250_port *up) |
| { |
| /* |
| * Exar ST16C2550 "A2" devices incorrectly detect as |
| * having an EFR, and report an ID of 0x0201. See |
| * http://linux.derkeiler.com/Mailing-Lists/Kernel/2004-11/4812.html |
| */ |
| if (autoconfig_read_divisor_id(up) == 0x0201 && size_fifo(up) == 16) |
| return 1; |
| |
| return 0; |
| } |
| |
| /* |
| * We know that the chip has FIFOs. Does it have an EFR? The |
| * EFR is located in the same register position as the IIR and |
| * we know the top two bits of the IIR are currently set. The |
| * EFR should contain zero. Try to read the EFR. |
| */ |
| static void autoconfig_16550a(struct uart_8250_port *up) |
| { |
| unsigned char status1, status2; |
| unsigned int iersave; |
| |
| up->port.type = PORT_16550A; |
| up->capabilities |= UART_CAP_FIFO; |
| |
| /* |
| * XR17V35x UARTs have an extra divisor register, DLD |
| * that gets enabled with when DLAB is set which will |
| * cause the device to incorrectly match and assign |
| * port type to PORT_16650. The EFR for this UART is |
| * found at offset 0x09. Instead check the Deice ID (DVID) |
| * register for a 2, 4 or 8 port UART. |
| */ |
| if (up->port.flags & UPF_EXAR_EFR) { |
| status1 = serial_in(up, UART_EXAR_DVID); |
| if (status1 == 0x82 || status1 == 0x84 || status1 == 0x88) { |
| DEBUG_AUTOCONF("Exar XR17V35x "); |
| up->port.type = PORT_XR17V35X; |
| up->capabilities |= UART_CAP_AFE | UART_CAP_EFR | |
| UART_CAP_SLEEP; |
| |
| return; |
| } |
| |
| } |
| |
| /* |
| * Check for presence of the EFR when DLAB is set. |
| * Only ST16C650V1 UARTs pass this test. |
| */ |
| serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A); |
| if (serial_in(up, UART_EFR) == 0) { |
| serial_out(up, UART_EFR, 0xA8); |
| if (serial_in(up, UART_EFR) != 0) { |
| DEBUG_AUTOCONF("EFRv1 "); |
| up->port.type = PORT_16650; |
| up->capabilities |= UART_CAP_EFR | UART_CAP_SLEEP; |
| } else { |
| serial_out(up, UART_LCR, 0); |
| serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | |
| UART_FCR7_64BYTE); |
| status1 = serial_in(up, UART_IIR) >> 5; |
| serial_out(up, UART_FCR, 0); |
| serial_out(up, UART_LCR, 0); |
| |
| if (status1 == 7) |
| up->port.type = PORT_16550A_FSL64; |
| else |
| DEBUG_AUTOCONF("Motorola 8xxx DUART "); |
| } |
| serial_out(up, UART_EFR, 0); |
| return; |
| } |
| |
| /* |
| * Maybe it requires 0xbf to be written to the LCR. |
| * (other ST16C650V2 UARTs, TI16C752A, etc) |
| */ |
| serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); |
| if (serial_in(up, UART_EFR) == 0 && !broken_efr(up)) { |
| DEBUG_AUTOCONF("EFRv2 "); |
| autoconfig_has_efr(up); |
| return; |
| } |
| |
| /* |
| * Check for a National Semiconductor SuperIO chip. |
| * Attempt to switch to bank 2, read the value of the LOOP bit |
| * from EXCR1. Switch back to bank 0, change it in MCR. Then |
| * switch back to bank 2, read it from EXCR1 again and check |
| * it's changed. If so, set baud_base in EXCR2 to 921600. -- dwmw2 |
| */ |
| serial_out(up, UART_LCR, 0); |
| status1 = serial8250_in_MCR(up); |
| serial_out(up, UART_LCR, 0xE0); |
| status2 = serial_in(up, 0x02); /* EXCR1 */ |
| |
| if (!((status2 ^ status1) & UART_MCR_LOOP)) { |
| serial_out(up, UART_LCR, 0); |
| serial8250_out_MCR(up, status1 ^ UART_MCR_LOOP); |
| serial_out(up, UART_LCR, 0xE0); |
| status2 = serial_in(up, 0x02); /* EXCR1 */ |
| serial_out(up, UART_LCR, 0); |
| serial8250_out_MCR(up, status1); |
| |
| if ((status2 ^ status1) & UART_MCR_LOOP) { |
| unsigned short quot; |
| |
| serial_out(up, UART_LCR, 0xE0); |
| |
| quot = serial_dl_read(up); |
| quot <<= 3; |
| |
| if (ns16550a_goto_highspeed(up)) |
| serial_dl_write(up, quot); |
| |
| serial_out(up, UART_LCR, 0); |
| |
| up->port.uartclk = 921600*16; |
| up->port.type = PORT_NS16550A; |
| up->capabilities |= UART_NATSEMI; |
| return; |
| } |
| } |
| |
| /* |
| * No EFR. Try to detect a TI16750, which only sets bit 5 of |
| * the IIR when 64 byte FIFO mode is enabled when DLAB is set. |
| * Try setting it with and without DLAB set. Cheap clones |
| * set bit 5 without DLAB set. |
| */ |
| serial_out(up, UART_LCR, 0); |
| serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE); |
| status1 = serial_in(up, UART_IIR) >> 5; |
| serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO); |
| serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A); |
| serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO | UART_FCR7_64BYTE); |
| status2 = serial_in(up, UART_IIR) >> 5; |
| serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO); |
| serial_out(up, UART_LCR, 0); |
| |
| DEBUG_AUTOCONF("iir1=%d iir2=%d ", status1, status2); |
| |
| if (status1 == 6 && status2 == 7) { |
| up->port.type = PORT_16750; |
| up->capabilities |= UART_CAP_AFE | UART_CAP_SLEEP; |
| return; |
| } |
| |
| /* |
| * Try writing and reading the UART_IER_UUE bit (b6). |
| * If it works, this is probably one of the Xscale platform's |
| * internal UARTs. |
| * We're going to explicitly set the UUE bit to 0 before |
| * trying to write and read a 1 just to make sure it's not |
| * already a 1 and maybe locked there before we even start start. |
| */ |
| iersave = serial_in(up, UART_IER); |
| serial_out(up, UART_IER, iersave & ~UART_IER_UUE); |
| if (!(serial_in(up, UART_IER) & UART_IER_UUE)) { |
| /* |
| * OK it's in a known zero state, try writing and reading |
| * without disturbing the current state of the other bits. |
| */ |
| serial_out(up, UART_IER, iersave | UART_IER_UUE); |
| if (serial_in(up, UART_IER) & UART_IER_UUE) { |
| /* |
| * It's an Xscale. |
| * We'll leave the UART_IER_UUE bit set to 1 (enabled). |
| */ |
| DEBUG_AUTOCONF("Xscale "); |
| up->port.type = PORT_XSCALE; |
| up->capabilities |= UART_CAP_UUE | UART_CAP_RTOIE; |
| return; |
| } |
| } else { |
| /* |
| * If we got here we couldn't force the IER_UUE bit to 0. |
| * Log it and continue. |
| */ |
| DEBUG_AUTOCONF("Couldn't force IER_UUE to 0 "); |
| } |
| serial_out(up, UART_IER, iersave); |
| |
| /* |
| * Exar uarts have EFR in a weird location |
| */ |
| if (up->port.flags & UPF_EXAR_EFR) { |
| DEBUG_AUTOCONF("Exar XR17D15x "); |
| up->port.type = PORT_XR17D15X; |
| up->capabilities |= UART_CAP_AFE | UART_CAP_EFR | |
| UART_CAP_SLEEP; |
| |
| return; |
| } |
| |
| /* |
| * We distinguish between 16550A and U6 16550A by counting |
| * how many bytes are in the FIFO. |
| */ |
| if (up->port.type == PORT_16550A && size_fifo(up) == 64) { |
| up->port.type = PORT_U6_16550A; |
| up->capabilities |= UART_CAP_AFE; |
| } |
| } |
| |
| /* |
| * This routine is called by rs_init() to initialize a specific serial |
| * port. It determines what type of UART chip this serial port is |
| * using: 8250, 16450, 16550, 16550A. The important question is |
| * whether or not this UART is a 16550A or not, since this will |
| * determine whether or not we can use its FIFO features or not. |
| */ |
| static void autoconfig(struct uart_8250_port *up) |
| { |
| unsigned char status1, scratch, scratch2, scratch3; |
| unsigned char save_lcr, save_mcr; |
| struct uart_port *port = &up->port; |
| unsigned long flags; |
| unsigned int old_capabilities; |
| |
| if (!port->iobase && !port->mapbase && !port->membase) |
| return; |
| |
| DEBUG_AUTOCONF("ttyS%d: autoconf (0x%04lx, 0x%p): ", |
| serial_index(port), port->iobase, port->membase); |
| |
| /* |
| * We really do need global IRQs disabled here - we're going to |
| * be frobbing the chips IRQ enable register to see if it exists. |
| */ |
| spin_lock_irqsave(&port->lock, flags); |
| |
| up->capabilities = 0; |
| up->bugs = 0; |
| |
| if (!(port->flags & UPF_BUGGY_UART)) { |
| /* |
| * Do a simple existence test first; if we fail this, |
| * there's no point trying anything else. |
| * |
| * 0x80 is used as a nonsense port to prevent against |
| * false positives due to ISA bus float. The |
| * assumption is that 0x80 is a non-existent port; |
| * which should be safe since include/asm/io.h also |
| * makes this assumption. |
| * |
| * Note: this is safe as long as MCR bit 4 is clear |
| * and the device is in "PC" mode. |
| */ |
| scratch = serial_in(up, UART_IER); |
| serial_out(up, UART_IER, 0); |
| #ifdef __i386__ |
| outb(0xff, 0x080); |
| #endif |
| /* |
| * Mask out IER[7:4] bits for test as some UARTs (e.g. TL |
| * 16C754B) allow only to modify them if an EFR bit is set. |
| */ |
| scratch2 = serial_in(up, UART_IER) & 0x0f; |
| serial_out(up, UART_IER, 0x0F); |
| #ifdef __i386__ |
| outb(0, 0x080); |
| #endif |
| scratch3 = serial_in(up, UART_IER) & 0x0f; |
| serial_out(up, UART_IER, scratch); |
| if (scratch2 != 0 || scratch3 != 0x0F) { |
| /* |
| * We failed; there's nothing here |
| */ |
| spin_unlock_irqrestore(&port->lock, flags); |
| DEBUG_AUTOCONF("IER test failed (%02x, %02x) ", |
| scratch2, scratch3); |
| goto out; |
| } |
| } |
| |
| save_mcr = serial8250_in_MCR(up); |
| save_lcr = serial_in(up, UART_LCR); |
| |
| /* |
| * Check to see if a UART is really there. Certain broken |
| * internal modems based on the Rockwell chipset fail this |
| * test, because they apparently don't implement the loopback |
| * test mode. So this test is skipped on the COM 1 through |
| * COM 4 ports. This *should* be safe, since no board |
| * manufacturer would be stupid enough to design a board |
| * that conflicts with COM 1-4 --- we hope! |
| */ |
| if (!(port->flags & UPF_SKIP_TEST)) { |
| serial8250_out_MCR(up, UART_MCR_LOOP | 0x0A); |
| status1 = serial_in(up, UART_MSR) & 0xF0; |
| serial8250_out_MCR(up, save_mcr); |
| if (status1 != 0x90) { |
| spin_unlock_irqrestore(&port->lock, flags); |
| DEBUG_AUTOCONF("LOOP test failed (%02x) ", |
| status1); |
| goto out; |
| } |
| } |
| |
| /* |
| * We're pretty sure there's a port here. Lets find out what |
| * type of port it is. The IIR top two bits allows us to find |
| * out if it's 8250 or 16450, 16550, 16550A or later. This |
| * determines what we test for next. |
| * |
| * We also initialise the EFR (if any) to zero for later. The |
| * EFR occupies the same register location as the FCR and IIR. |
| */ |
| serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); |
| serial_out(up, UART_EFR, 0); |
| serial_out(up, UART_LCR, 0); |
| |
| serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO); |
| scratch = serial_in(up, UART_IIR) >> 6; |
| |
| switch (scratch) { |
| case 0: |
| autoconfig_8250(up); |
| break; |
| case 1: |
| port->type = PORT_UNKNOWN; |
| break; |
| case 2: |
| port->type = PORT_16550; |
| break; |
| case 3: |
| autoconfig_16550a(up); |
| break; |
| } |
| |
| #ifdef CONFIG_SERIAL_8250_RSA |
| /* |
| * Only probe for RSA ports if we got the region. |
| */ |
| if (port->type == PORT_16550A && up->probe & UART_PROBE_RSA && |
| __enable_rsa(up)) |
| port->type = PORT_RSA; |
| #endif |
| |
| serial_out(up, UART_LCR, save_lcr); |
| |
| port->fifosize = uart_config[up->port.type].fifo_size; |
| old_capabilities = up->capabilities; |
| up->capabilities = uart_config[port->type].flags; |
| up->tx_loadsz = uart_config[port->type].tx_loadsz; |
| |
| if (port->type == PORT_UNKNOWN) |
| goto out_lock; |
| |
| /* |
| * Reset the UART. |
| */ |
| #ifdef CONFIG_SERIAL_8250_RSA |
| if (port->type == PORT_RSA) |
| serial_out(up, UART_RSA_FRR, 0); |
| #endif |
| serial8250_out_MCR(up, save_mcr); |
| serial8250_clear_fifos(up); |
| serial_in(up, UART_RX); |
| if (up->capabilities & UART_CAP_UUE) |
| serial_out(up, UART_IER, UART_IER_UUE); |
| else |
| serial_out(up, UART_IER, 0); |
| |
| out_lock: |
| spin_unlock_irqrestore(&port->lock, flags); |
| |
| /* |
| * Check if the device is a Fintek F81216A |
| */ |
| if (port->type == PORT_16550A) |
| fintek_8250_probe(up); |
| |
| if (up->capabilities != old_capabilities) { |
| pr_warn("ttyS%d: detected caps %08x should be %08x\n", |
| serial_index(port), old_capabilities, |
| up->capabilities); |
| } |
| out: |
| DEBUG_AUTOCONF("iir=%d ", scratch); |
| DEBUG_AUTOCONF("type=%s\n", uart_config[port->type].name); |
| } |
| |
| static void autoconfig_irq(struct uart_8250_port *up) |
| { |
| struct uart_port *port = &up->port; |
| unsigned char save_mcr, save_ier; |
| unsigned char save_ICP = 0; |
| unsigned int ICP = 0; |
| unsigned long irqs; |
| int irq; |
| |
| if (port->flags & UPF_FOURPORT) { |
| ICP = (port->iobase & 0xfe0) | 0x1f; |
| save_ICP = inb_p(ICP); |
| outb_p(0x80, ICP); |
| inb_p(ICP); |
| } |
| |
| if (uart_console(port)) |
| console_lock(); |
| |
| /* forget possible initially masked and pending IRQ */ |
| probe_irq_off(probe_irq_on()); |
| save_mcr = serial8250_in_MCR(up); |
| save_ier = serial_in(up, UART_IER); |
| serial8250_out_MCR(up, UART_MCR_OUT1 | UART_MCR_OUT2); |
| |
| irqs = probe_irq_on(); |
| serial8250_out_MCR(up, 0); |
| udelay(10); |
| if (port->flags & UPF_FOURPORT) { |
| serial8250_out_MCR(up, UART_MCR_DTR | UART_MCR_RTS); |
| } else { |
| serial8250_out_MCR(up, |
| UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2); |
| } |
| serial_out(up, UART_IER, 0x0f); /* enable all intrs */ |
| serial_in(up, UART_LSR); |
| serial_in(up, UART_RX); |
| serial_in(up, UART_IIR); |
| serial_in(up, UART_MSR); |
| serial_out(up, UART_TX, 0xFF); |
| udelay(20); |
| irq = probe_irq_off(irqs); |
| |
| serial8250_out_MCR(up, save_mcr); |
| serial_out(up, UART_IER, save_ier); |
| |
| if (port->flags & UPF_FOURPORT) |
| outb_p(save_ICP, ICP); |
| |
| if (uart_console(port)) |
| console_unlock(); |
| |
| port->irq = (irq > 0) ? irq : 0; |
| } |
| |
| static void serial8250_stop_rx(struct uart_port *port) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| |
| serial8250_rpm_get(up); |
| |
| up->ier &= ~(UART_IER_RLSI | UART_IER_RDI); |
| up->port.read_status_mask &= ~UART_LSR_DR; |
| serial_port_out(port, UART_IER, up->ier); |
| |
| serial8250_rpm_put(up); |
| } |
| |
| static void __do_stop_tx_rs485(struct uart_8250_port *p) |
| { |
| serial8250_em485_rts_after_send(p); |
| |
| /* |
| * Empty the RX FIFO, we are not interested in anything |
| * received during the half-duplex transmission. |
| * Enable previously disabled RX interrupts. |
| */ |
| if (!(p->port.rs485.flags & SER_RS485_RX_DURING_TX)) { |
| serial8250_clear_fifos(p); |
| |
| p->ier |= UART_IER_RLSI | UART_IER_RDI; |
| serial_port_out(&p->port, UART_IER, p->ier); |
| } |
| } |
| |
| static void serial8250_em485_handle_stop_tx(unsigned long arg) |
| { |
| struct uart_8250_port *p = (struct uart_8250_port *)arg; |
| struct uart_8250_em485 *em485 = p->em485; |
| unsigned long flags; |
| |
| serial8250_rpm_get(p); |
| spin_lock_irqsave(&p->port.lock, flags); |
| if (em485 && |
| em485->active_timer == &em485->stop_tx_timer) { |
| __do_stop_tx_rs485(p); |
| em485->active_timer = NULL; |
| } |
| spin_unlock_irqrestore(&p->port.lock, flags); |
| serial8250_rpm_put(p); |
| } |
| |
| static void __stop_tx_rs485(struct uart_8250_port *p) |
| { |
| struct uart_8250_em485 *em485 = p->em485; |
| |
| /* |
| * __do_stop_tx_rs485 is going to set RTS according to config |
| * AND flush RX FIFO if required. |
| */ |
| if (p->port.rs485.delay_rts_after_send > 0) { |
| em485->active_timer = &em485->stop_tx_timer; |
| mod_timer(&em485->stop_tx_timer, jiffies + |
| p->port.rs485.delay_rts_after_send * HZ / 1000); |
| } else { |
| __do_stop_tx_rs485(p); |
| } |
| } |
| |
| static inline void __do_stop_tx(struct uart_8250_port *p) |
| { |
| if (p->ier & UART_IER_THRI) { |
| p->ier &= ~UART_IER_THRI; |
| serial_out(p, UART_IER, p->ier); |
| serial8250_rpm_put_tx(p); |
| } |
| } |
| |
| static inline void __stop_tx(struct uart_8250_port *p) |
| { |
| struct uart_8250_em485 *em485 = p->em485; |
| |
| if (em485) { |
| unsigned char lsr = serial_in(p, UART_LSR); |
| /* |
| * To provide required timeing and allow FIFO transfer, |
| * __stop_tx_rs485() must be called only when both FIFO and |
| * shift register are empty. It is for device driver to enable |
| * interrupt on TEMT. |
| */ |
| if ((lsr & BOTH_EMPTY) != BOTH_EMPTY) |
| return; |
| |
| del_timer(&em485->start_tx_timer); |
| em485->active_timer = NULL; |
| |
| __stop_tx_rs485(p); |
| } |
| __do_stop_tx(p); |
| } |
| |
| static void serial8250_stop_tx(struct uart_port *port) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| |
| serial8250_rpm_get(up); |
| __stop_tx(up); |
| |
| /* |
| * We really want to stop the transmitter from sending. |
| */ |
| if (port->type == PORT_16C950) { |
| up->acr |= UART_ACR_TXDIS; |
| serial_icr_write(up, UART_ACR, up->acr); |
| } |
| serial8250_rpm_put(up); |
| } |
| |
| static inline void __start_tx(struct uart_port *port) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| |
| if (up->dma && !up->dma->tx_dma(up)) |
| return; |
| |
| if (!(up->ier & UART_IER_THRI)) { |
| up->ier |= UART_IER_THRI; |
| serial_port_out(port, UART_IER, up->ier); |
| |
| if (up->bugs & UART_BUG_TXEN) { |
| unsigned char lsr; |
| |
| lsr = serial_in(up, UART_LSR); |
| up->lsr_saved_flags |= lsr & LSR_SAVE_FLAGS; |
| if (lsr & UART_LSR_THRE) |
| serial8250_tx_chars(up); |
| } |
| } |
| |
| /* |
| * Re-enable the transmitter if we disabled it. |
| */ |
| if (port->type == PORT_16C950 && up->acr & UART_ACR_TXDIS) { |
| up->acr &= ~UART_ACR_TXDIS; |
| serial_icr_write(up, UART_ACR, up->acr); |
| } |
| } |
| |
| static inline void start_tx_rs485(struct uart_port *port) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| struct uart_8250_em485 *em485 = up->em485; |
| unsigned char mcr; |
| |
| if (!(up->port.rs485.flags & SER_RS485_RX_DURING_TX)) |
| serial8250_stop_rx(&up->port); |
| |
| del_timer(&em485->stop_tx_timer); |
| em485->active_timer = NULL; |
| |
| mcr = serial8250_in_MCR(up); |
| if (!!(up->port.rs485.flags & SER_RS485_RTS_ON_SEND) != |
| !!(mcr & UART_MCR_RTS)) { |
| if (up->port.rs485.flags & SER_RS485_RTS_ON_SEND) |
| mcr |= UART_MCR_RTS; |
| else |
| mcr &= ~UART_MCR_RTS; |
| serial8250_out_MCR(up, mcr); |
| |
| if (up->port.rs485.delay_rts_before_send > 0) { |
| em485->active_timer = &em485->start_tx_timer; |
| mod_timer(&em485->start_tx_timer, jiffies + |
| up->port.rs485.delay_rts_before_send * HZ / 1000); |
| return; |
| } |
| } |
| |
| __start_tx(port); |
| } |
| |
| static void serial8250_em485_handle_start_tx(unsigned long arg) |
| { |
| struct uart_8250_port *p = (struct uart_8250_port *)arg; |
| struct uart_8250_em485 *em485 = p->em485; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&p->port.lock, flags); |
| if (em485 && |
| em485->active_timer == &em485->start_tx_timer) { |
| __start_tx(&p->port); |
| em485->active_timer = NULL; |
| } |
| spin_unlock_irqrestore(&p->port.lock, flags); |
| } |
| |
| static void serial8250_start_tx(struct uart_port *port) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| struct uart_8250_em485 *em485 = up->em485; |
| |
| serial8250_rpm_get_tx(up); |
| |
| if (em485 && |
| em485->active_timer == &em485->start_tx_timer) |
| return; |
| |
| if (em485) |
| start_tx_rs485(port); |
| else |
| __start_tx(port); |
| } |
| |
| static void serial8250_throttle(struct uart_port *port) |
| { |
| port->throttle(port); |
| } |
| |
| static void serial8250_unthrottle(struct uart_port *port) |
| { |
| port->unthrottle(port); |
| } |
| |
| static void serial8250_disable_ms(struct uart_port *port) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| |
| /* no MSR capabilities */ |
| if (up->bugs & UART_BUG_NOMSR) |
| return; |
| |
| up->ier &= ~UART_IER_MSI; |
| serial_port_out(port, UART_IER, up->ier); |
| } |
| |
| static void serial8250_enable_ms(struct uart_port *port) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| |
| /* no MSR capabilities */ |
| if (up->bugs & UART_BUG_NOMSR) |
| return; |
| |
| up->ier |= UART_IER_MSI; |
| |
| serial8250_rpm_get(up); |
| serial_port_out(port, UART_IER, up->ier); |
| serial8250_rpm_put(up); |
| } |
| |
| static void serial8250_read_char(struct uart_8250_port *up, unsigned char lsr) |
| { |
| struct uart_port *port = &up->port; |
| unsigned char ch; |
| char flag = TTY_NORMAL; |
| |
| if (likely(lsr & UART_LSR_DR)) |
| ch = serial_in(up, UART_RX); |
| else |
| /* |
| * Intel 82571 has a Serial Over Lan device that will |
| * set UART_LSR_BI without setting UART_LSR_DR when |
| * it receives a break. To avoid reading from the |
| * receive buffer without UART_LSR_DR bit set, we |
| * just force the read character to be 0 |
| */ |
| ch = 0; |
| |
| port->icount.rx++; |
| |
| lsr |= up->lsr_saved_flags; |
| up->lsr_saved_flags = 0; |
| |
| if (unlikely(lsr & UART_LSR_BRK_ERROR_BITS)) { |
| if (lsr & UART_LSR_BI) { |
| lsr &= ~(UART_LSR_FE | UART_LSR_PE); |
| port->icount.brk++; |
| /* |
| * We do the SysRQ and SAK checking |
| * here because otherwise the break |
| * may get masked by ignore_status_mask |
| * or read_status_mask. |
| */ |
| if (uart_handle_break(port)) |
| return; |
| } else if (lsr & UART_LSR_PE) |
| port->icount.parity++; |
| else if (lsr & UART_LSR_FE) |
| port->icount.frame++; |
| if (lsr & UART_LSR_OE) |
| port->icount.overrun++; |
| |
| /* |
| * Mask off conditions which should be ignored. |
| */ |
| lsr &= port->read_status_mask; |
| |
| if (lsr & UART_LSR_BI) { |
| pr_debug("%s: handling break\n", __func__); |
| flag = TTY_BREAK; |
| } else if (lsr & UART_LSR_PE) |
| flag = TTY_PARITY; |
| else if (lsr & UART_LSR_FE) |
| flag = TTY_FRAME; |
| } |
| if (uart_handle_sysrq_char(port, ch)) |
| return; |
| |
| uart_insert_char(port, lsr, UART_LSR_OE, ch, flag); |
| } |
| |
| /* |
| * serial8250_rx_chars: processes according to the passed in LSR |
| * value, and returns the remaining LSR bits not handled |
| * by this Rx routine. |
| */ |
| unsigned char serial8250_rx_chars(struct uart_8250_port *up, unsigned char lsr) |
| { |
| struct uart_port *port = &up->port; |
| int max_count = 256; |
| |
| do { |
| serial8250_read_char(up, lsr); |
| if (--max_count == 0) |
| break; |
| lsr = serial_in(up, UART_LSR); |
| } while (lsr & (UART_LSR_DR | UART_LSR_BI)); |
| |
| tty_flip_buffer_push(&port->state->port); |
| return lsr; |
| } |
| EXPORT_SYMBOL_GPL(serial8250_rx_chars); |
| |
| void serial8250_tx_chars(struct uart_8250_port *up) |
| { |
| struct uart_port *port = &up->port; |
| struct circ_buf *xmit = &port->state->xmit; |
| int count; |
| |
| if (port->x_char) { |
| serial_out(up, UART_TX, port->x_char); |
| port->icount.tx++; |
| port->x_char = 0; |
| return; |
| } |
| if (uart_tx_stopped(port)) { |
| serial8250_stop_tx(port); |
| return; |
| } |
| if (uart_circ_empty(xmit)) { |
| __stop_tx(up); |
| return; |
| } |
| |
| count = up->tx_loadsz; |
| do { |
| serial_out(up, UART_TX, xmit->buf[xmit->tail]); |
| xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); |
| port->icount.tx++; |
| if (uart_circ_empty(xmit)) |
| break; |
| if ((up->capabilities & UART_CAP_HFIFO) && |
| (serial_in(up, UART_LSR) & BOTH_EMPTY) != BOTH_EMPTY) |
| break; |
| } while (--count > 0); |
| |
| if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) |
| uart_write_wakeup(port); |
| |
| pr_debug("%s: THRE\n", __func__); |
| |
| /* |
| * With RPM enabled, we have to wait until the FIFO is empty before the |
| * HW can go idle. So we get here once again with empty FIFO and disable |
| * the interrupt and RPM in __stop_tx() |
| */ |
| if (uart_circ_empty(xmit) && !(up->capabilities & UART_CAP_RPM)) |
| __stop_tx(up); |
| } |
| EXPORT_SYMBOL_GPL(serial8250_tx_chars); |
| |
| /* Caller holds uart port lock */ |
| unsigned int serial8250_modem_status(struct uart_8250_port *up) |
| { |
| struct uart_port *port = &up->port; |
| unsigned int status = serial_in(up, UART_MSR); |
| |
| status |= up->msr_saved_flags; |
| up->msr_saved_flags = 0; |
| if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI && |
| port->state != NULL) { |
| if (status & UART_MSR_TERI) |
| port->icount.rng++; |
| if (status & UART_MSR_DDSR) |
| port->icount.dsr++; |
| if (status & UART_MSR_DDCD) |
| uart_handle_dcd_change(port, status & UART_MSR_DCD); |
| if (status & UART_MSR_DCTS) |
| uart_handle_cts_change(port, status & UART_MSR_CTS); |
| |
| wake_up_interruptible(&port->state->port.delta_msr_wait); |
| } |
| |
| return status; |
| } |
| EXPORT_SYMBOL_GPL(serial8250_modem_status); |
| |
| static bool handle_rx_dma(struct uart_8250_port *up, unsigned int iir) |
| { |
| switch (iir & 0x3f) { |
| case UART_IIR_RX_TIMEOUT: |
| serial8250_rx_dma_flush(up); |
| /* fall-through */ |
| case UART_IIR_RLSI: |
| return true; |
| } |
| return up->dma->rx_dma(up); |
| } |
| |
| /* |
| * This handles the interrupt from one port. |
| */ |
| int serial8250_handle_irq(struct uart_port *port, unsigned int iir) |
| { |
| unsigned char status; |
| unsigned long flags; |
| struct uart_8250_port *up = up_to_u8250p(port); |
| |
| if (iir & UART_IIR_NO_INT) |
| return 0; |
| |
| spin_lock_irqsave(&port->lock, flags); |
| |
| status = serial_port_in(port, UART_LSR); |
| |
| pr_debug("%s: status = %x\n", __func__, status); |
| |
| if (status & (UART_LSR_DR | UART_LSR_BI)) { |
| if (!up->dma || handle_rx_dma(up, iir)) |
| status = serial8250_rx_chars(up, status); |
| } |
| serial8250_modem_status(up); |
| if ((!up->dma || up->dma->tx_err) && (status & UART_LSR_THRE)) |
| serial8250_tx_chars(up); |
| |
| spin_unlock_irqrestore(&port->lock, flags); |
| return 1; |
| } |
| EXPORT_SYMBOL_GPL(serial8250_handle_irq); |
| |
| static int serial8250_default_handle_irq(struct uart_port *port) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| unsigned int iir; |
| int ret; |
| |
| serial8250_rpm_get(up); |
| |
| iir = serial_port_in(port, UART_IIR); |
| ret = serial8250_handle_irq(port, iir); |
| |
| serial8250_rpm_put(up); |
| return ret; |
| } |
| |
| /* |
| * These Exar UARTs have an extra interrupt indicator that could |
| * fire for a few unimplemented interrupts. One of which is a |
| * wakeup event when coming out of sleep. Put this here just |
| * to be on the safe side that these interrupts don't go unhandled. |
| */ |
| static int exar_handle_irq(struct uart_port *port) |
| { |
| unsigned int iir = serial_port_in(port, UART_IIR); |
| int ret; |
| |
| ret = serial8250_handle_irq(port, iir); |
| |
| if ((port->type == PORT_XR17V35X) || |
| (port->type == PORT_XR17D15X)) { |
| serial_port_in(port, 0x80); |
| serial_port_in(port, 0x81); |
| serial_port_in(port, 0x82); |
| serial_port_in(port, 0x83); |
| } |
| |
| return ret; |
| } |
| |
| /* |
| * Newer 16550 compatible parts such as the SC16C650 & Altera 16550 Soft IP |
| * have a programmable TX threshold that triggers the THRE interrupt in |
| * the IIR register. In this case, the THRE interrupt indicates the FIFO |
| * has space available. Load it up with tx_loadsz bytes. |
| */ |
| static int serial8250_tx_threshold_handle_irq(struct uart_port *port) |
| { |
| unsigned long flags; |
| unsigned int iir = serial_port_in(port, UART_IIR); |
| |
| /* TX Threshold IRQ triggered so load up FIFO */ |
| if ((iir & UART_IIR_ID) == UART_IIR_THRI) { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| |
| spin_lock_irqsave(&port->lock, flags); |
| serial8250_tx_chars(up); |
| spin_unlock_irqrestore(&port->lock, flags); |
| } |
| |
| iir = serial_port_in(port, UART_IIR); |
| return serial8250_handle_irq(port, iir); |
| } |
| |
| static unsigned int serial8250_tx_empty(struct uart_port *port) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| unsigned long flags; |
| unsigned int lsr; |
| |
| serial8250_rpm_get(up); |
| |
| spin_lock_irqsave(&port->lock, flags); |
| lsr = serial_port_in(port, UART_LSR); |
| up->lsr_saved_flags |= lsr & LSR_SAVE_FLAGS; |
| spin_unlock_irqrestore(&port->lock, flags); |
| |
| serial8250_rpm_put(up); |
| |
| return (lsr & BOTH_EMPTY) == BOTH_EMPTY ? TIOCSER_TEMT : 0; |
| } |
| |
| unsigned int serial8250_do_get_mctrl(struct uart_port *port) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| unsigned int status; |
| unsigned int ret; |
| |
| serial8250_rpm_get(up); |
| status = serial8250_modem_status(up); |
| serial8250_rpm_put(up); |
| |
| ret = 0; |
| if (status & UART_MSR_DCD) |
| ret |= TIOCM_CAR; |
| if (status & UART_MSR_RI) |
| ret |= TIOCM_RNG; |
| if (status & UART_MSR_DSR) |
| ret |= TIOCM_DSR; |
| if (status & UART_MSR_CTS) |
| ret |= TIOCM_CTS; |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(serial8250_do_get_mctrl); |
| |
| static unsigned int serial8250_get_mctrl(struct uart_port *port) |
| { |
| if (port->get_mctrl) |
| return port->get_mctrl(port); |
| return serial8250_do_get_mctrl(port); |
| } |
| |
| void serial8250_do_set_mctrl(struct uart_port *port, unsigned int mctrl) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| unsigned char mcr = 0; |
| |
| if (mctrl & TIOCM_RTS) |
| mcr |= UART_MCR_RTS; |
| if (mctrl & TIOCM_DTR) |
| mcr |= UART_MCR_DTR; |
| if (mctrl & TIOCM_OUT1) |
| mcr |= UART_MCR_OUT1; |
| if (mctrl & TIOCM_OUT2) |
| mcr |= UART_MCR_OUT2; |
| if (mctrl & TIOCM_LOOP) |
| mcr |= UART_MCR_LOOP; |
| |
| mcr = (mcr & up->mcr_mask) | up->mcr_force | up->mcr; |
| |
| serial8250_out_MCR(up, mcr); |
| } |
| EXPORT_SYMBOL_GPL(serial8250_do_set_mctrl); |
| |
| static void serial8250_set_mctrl(struct uart_port *port, unsigned int mctrl) |
| { |
| if (port->set_mctrl) |
| port->set_mctrl(port, mctrl); |
| else |
| serial8250_do_set_mctrl(port, mctrl); |
| } |
| |
| static void serial8250_break_ctl(struct uart_port *port, int break_state) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| unsigned long flags; |
| |
| serial8250_rpm_get(up); |
| spin_lock_irqsave(&port->lock, flags); |
| if (break_state == -1) |
| up->lcr |= UART_LCR_SBC; |
| else |
| up->lcr &= ~UART_LCR_SBC; |
| serial_port_out(port, UART_LCR, up->lcr); |
| spin_unlock_irqrestore(&port->lock, flags); |
| serial8250_rpm_put(up); |
| } |
| |
| /* |
| * Wait for transmitter & holding register to empty |
| */ |
| static void wait_for_xmitr(struct uart_8250_port *up, int bits) |
| { |
| unsigned int status, tmout = 10000; |
| |
| /* Wait up to 10ms for the character(s) to be sent. */ |
| for (;;) { |
| status = serial_in(up, UART_LSR); |
| |
| up->lsr_saved_flags |= status & LSR_SAVE_FLAGS; |
| |
| if ((status & bits) == bits) |
| break; |
| if (--tmout == 0) |
| break; |
| udelay(1); |
| touch_nmi_watchdog(); |
| } |
| |
| /* Wait up to 1s for flow control if necessary */ |
| if (up->port.flags & UPF_CONS_FLOW) { |
| for (tmout = 1000000; tmout; tmout--) { |
| unsigned int msr = serial_in(up, UART_MSR); |
| up->msr_saved_flags |= msr & MSR_SAVE_FLAGS; |
| if (msr & UART_MSR_CTS) |
| break; |
| udelay(1); |
| touch_nmi_watchdog(); |
| } |
| } |
| } |
| |
| #ifdef CONFIG_CONSOLE_POLL |
| /* |
| * Console polling routines for writing and reading from the uart while |
| * in an interrupt or debug context. |
| */ |
| |
| static int serial8250_get_poll_char(struct uart_port *port) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| unsigned char lsr; |
| int status; |
| |
| serial8250_rpm_get(up); |
| |
| lsr = serial_port_in(port, UART_LSR); |
| |
| if (!(lsr & UART_LSR_DR)) { |
| status = NO_POLL_CHAR; |
| goto out; |
| } |
| |
| status = serial_port_in(port, UART_RX); |
| out: |
| serial8250_rpm_put(up); |
| return status; |
| } |
| |
| |
| static void serial8250_put_poll_char(struct uart_port *port, |
| unsigned char c) |
| { |
| unsigned int ier; |
| struct uart_8250_port *up = up_to_u8250p(port); |
| |
| serial8250_rpm_get(up); |
| /* |
| * First save the IER then disable the interrupts |
| */ |
| ier = serial_port_in(port, UART_IER); |
| if (up->capabilities & UART_CAP_UUE) |
| serial_port_out(port, UART_IER, UART_IER_UUE); |
| else |
| serial_port_out(port, UART_IER, 0); |
| |
| wait_for_xmitr(up, BOTH_EMPTY); |
| /* |
| * Send the character out. |
| */ |
| serial_port_out(port, UART_TX, c); |
| |
| /* |
| * Finally, wait for transmitter to become empty |
| * and restore the IER |
| */ |
| wait_for_xmitr(up, BOTH_EMPTY); |
| serial_port_out(port, UART_IER, ier); |
| serial8250_rpm_put(up); |
| } |
| |
| #endif /* CONFIG_CONSOLE_POLL */ |
| |
| int serial8250_do_startup(struct uart_port *port) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| unsigned long flags; |
| unsigned char lsr, iir; |
| int retval; |
| |
| if (!port->fifosize) |
| port->fifosize = uart_config[port->type].fifo_size; |
| if (!up->tx_loadsz) |
| up->tx_loadsz = uart_config[port->type].tx_loadsz; |
| if (!up->capabilities) |
| up->capabilities = uart_config[port->type].flags; |
| up->mcr = 0; |
| |
| if (port->iotype != up->cur_iotype) |
| set_io_from_upio(port); |
| |
| serial8250_rpm_get(up); |
| if (port->type == PORT_16C950) { |
| /* Wake up and initialize UART */ |
| up->acr = 0; |
| serial_port_out(port, UART_LCR, UART_LCR_CONF_MODE_B); |
| serial_port_out(port, UART_EFR, UART_EFR_ECB); |
| serial_port_out(port, UART_IER, 0); |
| serial_port_out(port, UART_LCR, 0); |
| serial_icr_write(up, UART_CSR, 0); /* Reset the UART */ |
| serial_port_out(port, UART_LCR, UART_LCR_CONF_MODE_B); |
| serial_port_out(port, UART_EFR, UART_EFR_ECB); |
| serial_port_out(port, UART_LCR, 0); |
| } |
| |
| #ifdef CONFIG_SERIAL_8250_RSA |
| /* |
| * If this is an RSA port, see if we can kick it up to the |
| * higher speed clock. |
| */ |
| enable_rsa(up); |
| #endif |
| |
| if (port->type == PORT_XR17V35X) { |
| /* |
| * First enable access to IER [7:5], ISR [5:4], FCR [5:4], |
| * MCR [7:5] and MSR [7:0] |
| */ |
| serial_port_out(port, UART_XR_EFR, UART_EFR_ECB); |
| |
| /* |
| * Make sure all interrups are masked until initialization is |
| * complete and the FIFOs are cleared |
| */ |
| serial_port_out(port, UART_IER, 0); |
| } |
| |
| /* |
| * Clear the FIFO buffers and disable them. |
| * (they will be reenabled in set_termios()) |
| */ |
| serial8250_clear_fifos(up); |
| |
| /* |
| * Clear the interrupt registers. |
| */ |
| serial_port_in(port, UART_LSR); |
| serial_port_in(port, UART_RX); |
| serial_port_in(port, UART_IIR); |
| serial_port_in(port, UART_MSR); |
| |
| /* |
| * At this point, there's no way the LSR could still be 0xff; |
| * if it is, then bail out, because there's likely no UART |
| * here. |
| */ |
| if (!(port->flags & UPF_BUGGY_UART) && |
| (serial_port_in(port, UART_LSR) == 0xff)) { |
| printk_ratelimited(KERN_INFO "ttyS%d: LSR safety check engaged!\n", |
| serial_index(port)); |
| retval = -ENODEV; |
| goto out; |
| } |
| |
| /* |
| * For a XR16C850, we need to set the trigger levels |
| */ |
| if (port->type == PORT_16850) { |
| unsigned char fctr; |
| |
| serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); |
| |
| fctr = serial_in(up, UART_FCTR) & ~(UART_FCTR_RX|UART_FCTR_TX); |
| serial_port_out(port, UART_FCTR, |
| fctr | UART_FCTR_TRGD | UART_FCTR_RX); |
| serial_port_out(port, UART_TRG, UART_TRG_96); |
| serial_port_out(port, UART_FCTR, |
| fctr | UART_FCTR_TRGD | UART_FCTR_TX); |
| serial_port_out(port, UART_TRG, UART_TRG_96); |
| |
| serial_port_out(port, UART_LCR, 0); |
| } |
| |
| /* |
| * For the Altera 16550 variants, set TX threshold trigger level. |
| */ |
| if (((port->type == PORT_ALTR_16550_F32) || |
| (port->type == PORT_ALTR_16550_F64) || |
| (port->type == PORT_ALTR_16550_F128)) && (port->fifosize > 1)) { |
| /* Bounds checking of TX threshold (valid 0 to fifosize-2) */ |
| if ((up->tx_loadsz < 2) || (up->tx_loadsz > port->fifosize)) { |
| pr_err("ttyS%d TX FIFO Threshold errors, skipping\n", |
| serial_index(port)); |
| } else { |
| serial_port_out(port, UART_ALTR_AFR, |
| UART_ALTR_EN_TXFIFO_LW); |
| serial_port_out(port, UART_ALTR_TX_LOW, |
| port->fifosize - up->tx_loadsz); |
| port->handle_irq = serial8250_tx_threshold_handle_irq; |
| } |
| } |
| |
| if (port->irq) { |
| unsigned char iir1; |
| /* |
| * Test for UARTs that do not reassert THRE when the |
| * transmitter is idle and the interrupt has already |
| * been cleared. Real 16550s should always reassert |
| * this interrupt whenever the transmitter is idle and |
| * the interrupt is enabled. Delays are necessary to |
| * allow register changes to become visible. |
| */ |
| spin_lock_irqsave(&port->lock, flags); |
| if (up->port.irqflags & IRQF_SHARED) |
| disable_irq_nosync(port->irq); |
| |
| wait_for_xmitr(up, UART_LSR_THRE); |
| serial_port_out_sync(port, UART_IER, UART_IER_THRI); |
| udelay(1); /* allow THRE to set */ |
| iir1 = serial_port_in(port, UART_IIR); |
| serial_port_out(port, UART_IER, 0); |
| serial_port_out_sync(port, UART_IER, UART_IER_THRI); |
| udelay(1); /* allow a working UART time to re-assert THRE */ |
| iir = serial_port_in(port, UART_IIR); |
| serial_port_out(port, UART_IER, 0); |
| |
| if (port->irqflags & IRQF_SHARED) |
| enable_irq(port->irq); |
| spin_unlock_irqrestore(&port->lock, flags); |
| |
| /* |
| * If the interrupt is not reasserted, or we otherwise |
| * don't trust the iir, setup a timer to kick the UART |
| * on a regular basis. |
| */ |
| if ((!(iir1 & UART_IIR_NO_INT) && (iir & UART_IIR_NO_INT)) || |
| up->port.flags & UPF_BUG_THRE) { |
| up->bugs |= UART_BUG_THRE; |
| } |
| } |
| |
| retval = up->ops->setup_irq(up); |
| if (retval) |
| goto out; |
| |
| /* |
| * Now, initialize the UART |
| */ |
| serial_port_out(port, UART_LCR, UART_LCR_WLEN8); |
| |
| spin_lock_irqsave(&port->lock, flags); |
| if (up->port.flags & UPF_FOURPORT) { |
| if (!up->port.irq) |
| up->port.mctrl |= TIOCM_OUT1; |
| } else |
| /* |
| * Most PC uarts need OUT2 raised to enable interrupts. |
| */ |
| if (port->irq) |
| up->port.mctrl |= TIOCM_OUT2; |
| |
| serial8250_set_mctrl(port, port->mctrl); |
| |
| /* |
| * Serial over Lan (SoL) hack: |
| * Intel 8257x Gigabit ethernet chips have a 16550 emulation, to be |
| * used for Serial Over Lan. Those chips take a longer time than a |
| * normal serial device to signalize that a transmission data was |
| * queued. Due to that, the above test generally fails. One solution |
| * would be to delay the reading of iir. However, this is not |
| * reliable, since the timeout is variable. So, let's just don't |
| * test if we receive TX irq. This way, we'll never enable |
| * UART_BUG_TXEN. |
| */ |
| if (up->port.flags & UPF_NO_TXEN_TEST) |
| goto dont_test_tx_en; |
| |
| /* |
| * Do a quick test to see if we receive an interrupt when we enable |
| * the TX irq. |
| */ |
| serial_port_out(port, UART_IER, UART_IER_THRI); |
| lsr = serial_port_in(port, UART_LSR); |
| iir = serial_port_in(port, UART_IIR); |
| serial_port_out(port, UART_IER, 0); |
| |
| if (lsr & UART_LSR_TEMT && iir & UART_IIR_NO_INT) { |
| if (!(up->bugs & UART_BUG_TXEN)) { |
| up->bugs |= UART_BUG_TXEN; |
| pr_debug("ttyS%d - enabling bad tx status workarounds\n", |
| serial_index(port)); |
| } |
| } else { |
| up->bugs &= ~UART_BUG_TXEN; |
| } |
| |
| dont_test_tx_en: |
| spin_unlock_irqrestore(&port->lock, flags); |
| |
| /* |
| * Clear the interrupt registers again for luck, and clear the |
| * saved flags to avoid getting false values from polling |
| * routines or the previous session. |
| */ |
| serial_port_in(port, UART_LSR); |
| serial_port_in(port, UART_RX); |
| serial_port_in(port, UART_IIR); |
| serial_port_in(port, UART_MSR); |
| up->lsr_saved_flags = 0; |
| up->msr_saved_flags = 0; |
| |
| /* |
| * Request DMA channels for both RX and TX. |
| */ |
| if (up->dma) { |
| retval = serial8250_request_dma(up); |
| if (retval) { |
| pr_warn_ratelimited("ttyS%d - failed to request DMA\n", |
| serial_index(port)); |
| up->dma = NULL; |
| } |
| } |
| |
| /* |
| * Set the IER shadow for rx interrupts but defer actual interrupt |
| * enable until after the FIFOs are enabled; otherwise, an already- |
| * active sender can swamp the interrupt handler with "too much work". |
| */ |
| up->ier = UART_IER_RLSI | UART_IER_RDI; |
| |
| if (port->flags & UPF_FOURPORT) { |
| unsigned int icp; |
| /* |
| * Enable interrupts on the AST Fourport board |
| */ |
| icp = (port->iobase & 0xfe0) | 0x01f; |
| outb_p(0x80, icp); |
| inb_p(icp); |
| } |
| retval = 0; |
| out: |
| serial8250_rpm_put(up); |
| return retval; |
| } |
| EXPORT_SYMBOL_GPL(serial8250_do_startup); |
| |
| static int serial8250_startup(struct uart_port *port) |
| { |
| if (port->startup) |
| return port->startup(port); |
| return serial8250_do_startup(port); |
| } |
| |
| void serial8250_do_shutdown(struct uart_port *port) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| unsigned long flags; |
| |
| serial8250_rpm_get(up); |
| /* |
| * Disable interrupts from this port |
| */ |
| spin_lock_irqsave(&port->lock, flags); |
| up->ier = 0; |
| serial_port_out(port, UART_IER, 0); |
| spin_unlock_irqrestore(&port->lock, flags); |
| |
| synchronize_irq(port->irq); |
| |
| if (up->dma) |
| serial8250_release_dma(up); |
| |
| spin_lock_irqsave(&port->lock, flags); |
| if (port->flags & UPF_FOURPORT) { |
| /* reset interrupts on the AST Fourport board */ |
| inb((port->iobase & 0xfe0) | 0x1f); |
| port->mctrl |= TIOCM_OUT1; |
| } else |
| port->mctrl &= ~TIOCM_OUT2; |
| |
| serial8250_set_mctrl(port, port->mctrl); |
| spin_unlock_irqrestore(&port->lock, flags); |
| |
| /* |
| * Disable break condition and FIFOs |
| */ |
| serial_port_out(port, UART_LCR, |
| serial_port_in(port, UART_LCR) & ~UART_LCR_SBC); |
| serial8250_clear_fifos(up); |
| |
| #ifdef CONFIG_SERIAL_8250_RSA |
| /* |
| * Reset the RSA board back to 115kbps compat mode. |
| */ |
| disable_rsa(up); |
| #endif |
| |
| /* |
| * Read data port to reset things, and then unlink from |
| * the IRQ chain. |
| */ |
| serial_port_in(port, UART_RX); |
| serial8250_rpm_put(up); |
| |
| up->ops->release_irq(up); |
| } |
| EXPORT_SYMBOL_GPL(serial8250_do_shutdown); |
| |
| static void serial8250_shutdown(struct uart_port *port) |
| { |
| if (port->shutdown) |
| port->shutdown(port); |
| else |
| serial8250_do_shutdown(port); |
| } |
| |
| /* |
| * XR17V35x UARTs have an extra fractional divisor register (DLD) |
| * Calculate divisor with extra 4-bit fractional portion |
| */ |
| static unsigned int xr17v35x_get_divisor(struct uart_8250_port *up, |
| unsigned int baud, |
| unsigned int *frac) |
| { |
| struct uart_port *port = &up->port; |
| unsigned int quot_16; |
| |
| quot_16 = DIV_ROUND_CLOSEST(port->uartclk, baud); |
| *frac = quot_16 & 0x0f; |
| |
| return quot_16 >> 4; |
| } |
| |
| static unsigned int serial8250_get_divisor(struct uart_8250_port *up, |
| unsigned int baud, |
| unsigned int *frac) |
| { |
| struct uart_port *port = &up->port; |
| unsigned int quot; |
| |
| /* |
| * Handle magic divisors for baud rates above baud_base on |
| * SMSC SuperIO chips. |
| * |
| */ |
| if ((port->flags & UPF_MAGIC_MULTIPLIER) && |
| baud == (port->uartclk/4)) |
| quot = 0x8001; |
| else if ((port->flags & UPF_MAGIC_MULTIPLIER) && |
| baud == (port->uartclk/8)) |
| quot = 0x8002; |
| else if (up->port.type == PORT_XR17V35X) |
| quot = xr17v35x_get_divisor(up, baud, frac); |
| else |
| quot = uart_get_divisor(port, baud); |
| |
| /* |
| * Oxford Semi 952 rev B workaround |
| */ |
| if (up->bugs & UART_BUG_QUOT && (quot & 0xff) == 0) |
| quot++; |
| |
| return quot; |
| } |
| |
| static unsigned char serial8250_compute_lcr(struct uart_8250_port *up, |
| tcflag_t c_cflag) |
| { |
| unsigned char cval; |
| |
| switch (c_cflag & CSIZE) { |
| case CS5: |
| cval = UART_LCR_WLEN5; |
| break; |
| case CS6: |
| cval = UART_LCR_WLEN6; |
| break; |
| case CS7: |
| cval = UART_LCR_WLEN7; |
| break; |
| default: |
| case CS8: |
| cval = UART_LCR_WLEN8; |
| break; |
| } |
| |
| if (c_cflag & CSTOPB) |
| cval |= UART_LCR_STOP; |
| if (c_cflag & PARENB) { |
| cval |= UART_LCR_PARITY; |
| if (up->bugs & UART_BUG_PARITY) |
| up->fifo_bug = true; |
| } |
| if (!(c_cflag & PARODD)) |
| cval |= UART_LCR_EPAR; |
| #ifdef CMSPAR |
| if (c_cflag & CMSPAR) |
| cval |= UART_LCR_SPAR; |
| #endif |
| |
| return cval; |
| } |
| |
| static void serial8250_set_divisor(struct uart_port *port, unsigned int baud, |
| unsigned int quot, unsigned int quot_frac) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| |
| /* Workaround to enable 115200 baud on OMAP1510 internal ports */ |
| if (is_omap1510_8250(up)) { |
| if (baud == 115200) { |
| quot = 1; |
| serial_port_out(port, UART_OMAP_OSC_12M_SEL, 1); |
| } else |
| serial_port_out(port, UART_OMAP_OSC_12M_SEL, 0); |
| } |
| |
| /* |
| * For NatSemi, switch to bank 2 not bank 1, to avoid resetting EXCR2, |
| * otherwise just set DLAB |
| */ |
| if (up->capabilities & UART_NATSEMI) |
| serial_port_out(port, UART_LCR, 0xe0); |
| else |
| serial_port_out(port, UART_LCR, up->lcr | UART_LCR_DLAB); |
| |
| serial_dl_write(up, quot); |
| |
| /* XR17V35x UARTs have an extra fractional divisor register (DLD) */ |
| if (up->port.type == PORT_XR17V35X) |
| serial_port_out(port, 0x2, quot_frac); |
| } |
| |
| static unsigned int serial8250_get_baud_rate(struct uart_port *port, |
| struct ktermios *termios, |
| struct ktermios *old) |
| { |
| /* |
| * Ask the core to calculate the divisor for us. |
| * Allow 1% tolerance at the upper limit so uart clks marginally |
| * slower than nominal still match standard baud rates without |
| * causing transmission errors. |
| */ |
| return uart_get_baud_rate(port, termios, old, |
| port->uartclk / 16 / 0xffff, |
| port->uartclk); |
| } |
| |
| void |
| serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios, |
| struct ktermios *old) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| unsigned char cval; |
| unsigned long flags; |
| unsigned int baud, quot, frac = 0; |
| |
| cval = serial8250_compute_lcr(up, termios->c_cflag); |
| |
| baud = serial8250_get_baud_rate(port, termios, old); |
| quot = serial8250_get_divisor(up, baud, &frac); |
| |
| /* |
| * Ok, we're now changing the port state. Do it with |
| * interrupts disabled. |
| */ |
| serial8250_rpm_get(up); |
| spin_lock_irqsave(&port->lock, flags); |
| |
| up->lcr = cval; /* Save computed LCR */ |
| |
| if (up->capabilities & UART_CAP_FIFO && port->fifosize > 1) { |
| /* NOTE: If fifo_bug is not set, a user can set RX_trigger. */ |
| if ((baud < 2400 && !up->dma) || up->fifo_bug) { |
| up->fcr &= ~UART_FCR_TRIGGER_MASK; |
| up->fcr |= UART_FCR_TRIGGER_1; |
| } |
| } |
| |
| /* |
| * MCR-based auto flow control. When AFE is enabled, RTS will be |
| * deasserted when the receive FIFO contains more characters than |
| * the trigger, or the MCR RTS bit is cleared. |
| */ |
| if (up->capabilities & UART_CAP_AFE) { |
| up->mcr &= ~UART_MCR_AFE; |
| if (termios->c_cflag & CRTSCTS) |
| up->mcr |= UART_MCR_AFE; |
| } |
| |
| /* |
| * Update the per-port timeout. |
| */ |
| uart_update_timeout(port, termios->c_cflag, baud); |
| |
| port->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR; |
| if (termios->c_iflag & INPCK) |
| port->read_status_mask |= UART_LSR_FE | UART_LSR_PE; |
| if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK)) |
| port->read_status_mask |= UART_LSR_BI; |
| |
| /* |
| * Characteres to ignore |
| */ |
| port->ignore_status_mask = 0; |
| if (termios->c_iflag & IGNPAR) |
| port->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE; |
| if (termios->c_iflag & IGNBRK) { |
| port->ignore_status_mask |= UART_LSR_BI; |
| /* |
| * If we're ignoring parity and break indicators, |
| * ignore overruns too (for real raw support). |
| */ |
| if (termios->c_iflag & IGNPAR) |
| port->ignore_status_mask |= UART_LSR_OE; |
| } |
| |
| /* |
| * ignore all characters if CREAD is not set |
| */ |
| if ((termios->c_cflag & CREAD) == 0) |
| port->ignore_status_mask |= UART_LSR_DR; |
| |
| /* |
| * CTS flow control flag and modem status interrupts |
| */ |
| up->ier &= ~UART_IER_MSI; |
| if (!(up->bugs & UART_BUG_NOMSR) && |
| UART_ENABLE_MS(&up->port, termios->c_cflag)) |
| up->ier |= UART_IER_MSI; |
| if (up->capabilities & UART_CAP_UUE) |
| up->ier |= UART_IER_UUE; |
| if (up->capabilities & UART_CAP_RTOIE) |
| up->ier |= UART_IER_RTOIE; |
| |
| serial_port_out(port, UART_IER, up->ier); |
| |
| if (up->capabilities & UART_CAP_EFR) { |
| unsigned char efr = 0; |
| /* |
| * TI16C752/Startech hardware flow control. FIXME: |
| * - TI16C752 requires control thresholds to be set. |
| * - UART_MCR_RTS is ineffective if auto-RTS mode is enabled. |
| */ |
| if (termios->c_cflag & CRTSCTS) |
| efr |= UART_EFR_CTS; |
| |
| serial_port_out(port, UART_LCR, UART_LCR_CONF_MODE_B); |
| if (port->flags & UPF_EXAR_EFR) |
| serial_port_out(port, UART_XR_EFR, efr); |
| else |
| serial_port_out(port, UART_EFR, efr); |
| } |
| |
| serial8250_set_divisor(port, baud, quot, frac); |
| |
| /* |
| * LCR DLAB must be set to enable 64-byte FIFO mode. If the FCR |
| * is written without DLAB set, this mode will be disabled. |
| */ |
| if (port->type == PORT_16750) |
| serial_port_out(port, UART_FCR, up->fcr); |
| |
| serial_port_out(port, UART_LCR, up->lcr); /* reset DLAB */ |
| if (port->type != PORT_16750) { |
| /* emulated UARTs (Lucent Venus 167x) need two steps */ |
| if (up->fcr & UART_FCR_ENABLE_FIFO) |
| serial_port_out(port, UART_FCR, UART_FCR_ENABLE_FIFO); |
| serial_port_out(port, UART_FCR, up->fcr); /* set fcr */ |
| } |
| serial8250_set_mctrl(port, port->mctrl); |
| spin_unlock_irqrestore(&port->lock, flags); |
| serial8250_rpm_put(up); |
| |
| /* Don't rewrite B0 */ |
| if (tty_termios_baud_rate(termios)) |
| tty_termios_encode_baud_rate(termios, baud, baud); |
| } |
| EXPORT_SYMBOL(serial8250_do_set_termios); |
| |
| static void |
| serial8250_set_termios(struct uart_port *port, struct ktermios *termios, |
| struct ktermios *old) |
| { |
| if (port->set_termios) |
| port->set_termios(port, termios, old); |
| else |
| serial8250_do_set_termios(port, termios, old); |
| } |
| |
| void serial8250_do_set_ldisc(struct uart_port *port, struct ktermios *termios) |
| { |
| if (termios->c_line == N_PPS) { |
| port->flags |= UPF_HARDPPS_CD; |
| spin_lock_irq(&port->lock); |
| serial8250_enable_ms(port); |
| spin_unlock_irq(&port->lock); |
| } else { |
| port->flags &= ~UPF_HARDPPS_CD; |
| if (!UART_ENABLE_MS(port, termios->c_cflag)) { |
| spin_lock_irq(&port->lock); |
| serial8250_disable_ms(port); |
| spin_unlock_irq(&port->lock); |
| } |
| } |
| } |
| EXPORT_SYMBOL_GPL(serial8250_do_set_ldisc); |
| |
| static void |
| serial8250_set_ldisc(struct uart_port *port, struct ktermios *termios) |
| { |
| if (port->set_ldisc) |
| port->set_ldisc(port, termios); |
| else |
| serial8250_do_set_ldisc(port, termios); |
| } |
| |
| void serial8250_do_pm(struct uart_port *port, unsigned int state, |
| unsigned int oldstate) |
| { |
| struct uart_8250_port *p = up_to_u8250p(port); |
| |
| serial8250_set_sleep(p, state != 0); |
| } |
| EXPORT_SYMBOL(serial8250_do_pm); |
| |
| static void |
| serial8250_pm(struct uart_port *port, unsigned int state, |
| unsigned int oldstate) |
| { |
| if (port->pm) |
| port->pm(port, state, oldstate); |
| else |
| serial8250_do_pm(port, state, oldstate); |
| } |
| |
| static unsigned int serial8250_port_size(struct uart_8250_port *pt) |
| { |
| if (pt->port.mapsize) |
| return pt->port.mapsize; |
| if (pt->port.iotype == UPIO_AU) { |
| if (pt->port.type == PORT_RT2880) |
| return 0x100; |
| return 0x1000; |
| } |
| if (is_omap1_8250(pt)) |
| return 0x16 << pt->port.regshift; |
| |
| return 8 << pt->port.regshift; |
| } |
| |
| /* |
| * Resource handling. |
| */ |
| static int serial8250_request_std_resource(struct uart_8250_port *up) |
| { |
| unsigned int size = serial8250_port_size(up); |
| struct uart_port *port = &up->port; |
| int ret = 0; |
| |
| switch (port->iotype) { |
| case UPIO_AU: |
| case UPIO_TSI: |
| case UPIO_MEM32: |
| case UPIO_MEM32BE: |
| case UPIO_MEM16: |
| case UPIO_MEM: |
| if (!port->mapbase) |
| break; |
| |
| if (!request_mem_region(port->mapbase, size, "serial")) { |
| ret = -EBUSY; |
| break; |
| } |
| |
| if (port->flags & UPF_IOREMAP) { |
| port->membase = ioremap_nocache(port->mapbase, size); |
| if (!port->membase) { |
| release_mem_region(port->mapbase, size); |
| ret = -ENOMEM; |
| } |
| } |
| break; |
| |
| case UPIO_HUB6: |
| case UPIO_PORT: |
| if (!request_region(port->iobase, size, "serial")) |
| ret = -EBUSY; |
| break; |
| } |
| return ret; |
| } |
| |
| static void serial8250_release_std_resource(struct uart_8250_port *up) |
| { |
| unsigned int size = serial8250_port_size(up); |
| struct uart_port *port = &up->port; |
| |
| switch (port->iotype) { |
| case UPIO_AU: |
| case UPIO_TSI: |
| case UPIO_MEM32: |
| case UPIO_MEM32BE: |
| case UPIO_MEM16: |
| case UPIO_MEM: |
| if (!port->mapbase) |
| break; |
| |
| if (port->flags & UPF_IOREMAP) { |
| iounmap(port->membase); |
| port->membase = NULL; |
| } |
| |
| release_mem_region(port->mapbase, size); |
| break; |
| |
| case UPIO_HUB6: |
| case UPIO_PORT: |
| release_region(port->iobase, size); |
| break; |
| } |
| } |
| |
| static void serial8250_release_port(struct uart_port *port) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| |
| serial8250_release_std_resource(up); |
| } |
| |
| static int serial8250_request_port(struct uart_port *port) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| |
| return serial8250_request_std_resource(up); |
| } |
| |
| static int fcr_get_rxtrig_bytes(struct uart_8250_port *up) |
| { |
| const struct serial8250_config *conf_type = &uart_config[up->port.type]; |
| unsigned char bytes; |
| |
| bytes = conf_type->rxtrig_bytes[UART_FCR_R_TRIG_BITS(up->fcr)]; |
| |
| return bytes ? bytes : -EOPNOTSUPP; |
| } |
| |
| static int bytes_to_fcr_rxtrig(struct uart_8250_port *up, unsigned char bytes) |
| { |
| const struct serial8250_config *conf_type = &uart_config[up->port.type]; |
| int i; |
| |
| if (!conf_type->rxtrig_bytes[UART_FCR_R_TRIG_BITS(UART_FCR_R_TRIG_00)]) |
| return -EOPNOTSUPP; |
| |
| for (i = 1; i < UART_FCR_R_TRIG_MAX_STATE; i++) { |
| if (bytes < conf_type->rxtrig_bytes[i]) |
| /* Use the nearest lower value */ |
| return (--i) << UART_FCR_R_TRIG_SHIFT; |
| } |
| |
| return UART_FCR_R_TRIG_11; |
| } |
| |
| static int do_get_rxtrig(struct tty_port *port) |
| { |
| struct uart_state *state = container_of(port, struct uart_state, port); |
| struct uart_port *uport = state->uart_port; |
| struct uart_8250_port *up = up_to_u8250p(uport); |
| |
| if (!(up->capabilities & UART_CAP_FIFO) || uport->fifosize <= 1) |
| return -EINVAL; |
| |
| return fcr_get_rxtrig_bytes(up); |
| } |
| |
| static int do_serial8250_get_rxtrig(struct tty_port *port) |
| { |
| int rxtrig_bytes; |
| |
| mutex_lock(&port->mutex); |
| rxtrig_bytes = do_get_rxtrig(port); |
| mutex_unlock(&port->mutex); |
| |
| return rxtrig_bytes; |
| } |
| |
| static ssize_t serial8250_get_attr_rx_trig_bytes(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| struct tty_port *port = dev_get_drvdata(dev); |
| int rxtrig_bytes; |
| |
| rxtrig_bytes = do_serial8250_get_rxtrig(port); |
| if (rxtrig_bytes < 0) |
| return rxtrig_bytes; |
| |
| return snprintf(buf, PAGE_SIZE, "%d\n", rxtrig_bytes); |
| } |
| |
| static int do_set_rxtrig(struct tty_port *port, unsigned char bytes) |
| { |
| struct uart_state *state = container_of(port, struct uart_state, port); |
| struct uart_port *uport = state->uart_port; |
| struct uart_8250_port *up = up_to_u8250p(uport); |
| int rxtrig; |
| |
| if (!(up->capabilities & UART_CAP_FIFO) || uport->fifosize <= 1 || |
| up->fifo_bug) |
| return -EINVAL; |
| |
| rxtrig = bytes_to_fcr_rxtrig(up, bytes); |
| if (rxtrig < 0) |
| return rxtrig; |
| |
| serial8250_clear_fifos(up); |
| up->fcr &= ~UART_FCR_TRIGGER_MASK; |
| up->fcr |= (unsigned char)rxtrig; |
| serial_out(up, UART_FCR, up->fcr); |
| return 0; |
| } |
| |
| static int do_serial8250_set_rxtrig(struct tty_port *port, unsigned char bytes) |
| { |
| int ret; |
| |
| mutex_lock(&port->mutex); |
| ret = do_set_rxtrig(port, bytes); |
| mutex_unlock(&port->mutex); |
| |
| return ret; |
| } |
| |
| static ssize_t serial8250_set_attr_rx_trig_bytes(struct device *dev, |
| struct device_attribute *attr, const char *buf, size_t count) |
| { |
| struct tty_port *port = dev_get_drvdata(dev); |
| unsigned char bytes; |
| int ret; |
| |
| if (!count) |
| return -EINVAL; |
| |
| ret = kstrtou8(buf, 10, &bytes); |
| if (ret < 0) |
| return ret; |
| |
| ret = do_serial8250_set_rxtrig(port, bytes); |
| if (ret < 0) |
| return ret; |
| |
| return count; |
| } |
| |
| static DEVICE_ATTR(rx_trig_bytes, S_IRUSR | S_IWUSR | S_IRGRP, |
| serial8250_get_attr_rx_trig_bytes, |
| serial8250_set_attr_rx_trig_bytes); |
| |
| static struct attribute *serial8250_dev_attrs[] = { |
| &dev_attr_rx_trig_bytes.attr, |
| NULL, |
| }; |
| |
| static struct attribute_group serial8250_dev_attr_group = { |
| .attrs = serial8250_dev_attrs, |
| }; |
| |
| static void register_dev_spec_attr_grp(struct uart_8250_port *up) |
| { |
| const struct serial8250_config *conf_type = &uart_config[up->port.type]; |
| |
| if (conf_type->rxtrig_bytes[0]) |
| up->port.attr_group = &serial8250_dev_attr_group; |
| } |
| |
| static void serial8250_config_port(struct uart_port *port, int flags) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| int ret; |
| |
| /* |
| * Find the region that we can probe for. This in turn |
| * tells us whether we can probe for the type of port. |
| */ |
| ret = serial8250_request_std_resource(up); |
| if (ret < 0) |
| return; |
| |
| if (port->iotype != up->cur_iotype) |
| set_io_from_upio(port); |
| |
| if (flags & UART_CONFIG_TYPE) |
| autoconfig(up); |
| |
| /* if access method is AU, it is a 16550 with a quirk */ |
| if (port->type == PORT_16550A && port->iotype == UPIO_AU) |
| up->bugs |= UART_BUG_NOMSR; |
| |
| /* HW bugs may trigger IRQ while IIR == NO_INT */ |
| if (port->type == PORT_TEGRA) |
| up->bugs |= UART_BUG_NOMSR; |
| |
| if (port->type != PORT_UNKNOWN && flags & UART_CONFIG_IRQ) |
| autoconfig_irq(up); |
| |
| if (port->type == PORT_UNKNOWN) |
| serial8250_release_std_resource(up); |
| |
| /* Fixme: probably not the best place for this */ |
| if ((port->type == PORT_XR17V35X) || |
| (port->type == PORT_XR17D15X)) |
| port->handle_irq = exar_handle_irq; |
| |
| register_dev_spec_attr_grp(up); |
| up->fcr = uart_config[up->port.type].fcr; |
| } |
| |
| static int |
| serial8250_verify_port(struct uart_port *port, struct serial_struct *ser) |
| { |
| if (ser->irq >= nr_irqs || ser->irq < 0 || |
| ser->baud_base < 9600 || ser->type < PORT_UNKNOWN || |
| ser->type >= ARRAY_SIZE(uart_config) || ser->type == PORT_CIRRUS || |
| ser->type == PORT_STARTECH) |
| return -EINVAL; |
| return 0; |
| } |
| |
| static const char *serial8250_type(struct uart_port *port) |
| { |
| int type = port->type; |
| |
| if (type >= ARRAY_SIZE(uart_config)) |
| type = 0; |
| return uart_config[type].name; |
| } |
| |
| static const struct uart_ops serial8250_pops = { |
| .tx_empty = serial8250_tx_empty, |
| .set_mctrl = serial8250_set_mctrl, |
| .get_mctrl = serial8250_get_mctrl, |
| .stop_tx = serial8250_stop_tx, |
| .start_tx = serial8250_start_tx, |
| .throttle = serial8250_throttle, |
| .unthrottle = serial8250_unthrottle, |
| .stop_rx = serial8250_stop_rx, |
| .enable_ms = serial8250_enable_ms, |
| .break_ctl = serial8250_break_ctl, |
| .startup = serial8250_startup, |
| .shutdown = serial8250_shutdown, |
| .set_termios = serial8250_set_termios, |
| .set_ldisc = serial8250_set_ldisc, |
| .pm = serial8250_pm, |
| .type = serial8250_type, |
| .release_port = serial8250_release_port, |
| .request_port = serial8250_request_port, |
| .config_port = serial8250_config_port, |
| .verify_port = serial8250_verify_port, |
| #ifdef CONFIG_CONSOLE_POLL |
| .poll_get_char = serial8250_get_poll_char, |
| .poll_put_char = serial8250_put_poll_char, |
| #endif |
| }; |
| |
| void serial8250_init_port(struct uart_8250_port *up) |
| { |
| struct uart_port *port = &up->port; |
| |
| spin_lock_init(&port->lock); |
| port->ops = &serial8250_pops; |
| |
| up->cur_iotype = 0xFF; |
| } |
| EXPORT_SYMBOL_GPL(serial8250_init_port); |
| |
| void serial8250_set_defaults(struct uart_8250_port *up) |
| { |
| struct uart_port *port = &up->port; |
| |
| if (up->port.flags & UPF_FIXED_TYPE) { |
| unsigned int type = up->port.type; |
| |
| if (!up->port.fifosize) |
| up->port.fifosize = uart_config[type].fifo_size; |
| if (!up->tx_loadsz) |
| up->tx_loadsz = uart_config[type].tx_loadsz; |
| if (!up->capabilities) |
| up->capabilities = uart_config[type].flags; |
| } |
| |
| set_io_from_upio(port); |
| |
| /* default dma handlers */ |
| if (up->dma) { |
| if (!up->dma->tx_dma) |
| up->dma->tx_dma = serial8250_tx_dma; |
| if (!up->dma->rx_dma) |
| up->dma->rx_dma = serial8250_rx_dma; |
| } |
| } |
| EXPORT_SYMBOL_GPL(serial8250_set_defaults); |
| |
| #ifdef CONFIG_SERIAL_8250_CONSOLE |
| |
| static void serial8250_console_putchar(struct uart_port *port, int ch) |
| { |
| struct uart_8250_port *up = up_to_u8250p(port); |
| |
| wait_for_xmitr(up, UART_LSR_THRE); |
| serial_port_out(port, UART_TX, ch); |
| } |
| |
| /* |
| * Restore serial console when h/w power-off detected |
| */ |
| static void serial8250_console_restore(struct uart_8250_port *up) |
| { |
| struct uart_port *port = &up->port; |
| struct ktermios termios; |
| unsigned int baud, quot, frac = 0; |
| |
| termios.c_cflag = port->cons->cflag; |
| if (port->state->port.tty && termios.c_cflag == 0) |
| termios.c_cflag = port->state->port.tty->termios.c_cflag; |
| |
| baud = serial8250_get_baud_rate(port, &termios, NULL); |
| quot = serial8250_get_divisor(up, baud, &frac); |
| |
| serial8250_set_divisor(port, baud, quot, frac); |
| serial_port_out(port, UART_LCR, up->lcr); |
| serial8250_out_MCR(up, UART_MCR_DTR | UART_MCR_RTS); |
| } |
| |
| /* |
| * Print a string to the serial port trying not to disturb |
| * any possible real use of the port... |
| * |
| * The console_lock must be held when we get here. |
| */ |
| void serial8250_console_write(struct uart_8250_port *up, const char *s, |
| unsigned int count) |
| { |
| struct uart_port *port = &up->port; |
| unsigned long flags; |
| unsigned int ier; |
| int locked = 1; |
| |
| touch_nmi_watchdog(); |
| |
| serial8250_rpm_get(up); |
| |
| if (port->sysrq) |
| locked = 0; |
| else if (oops_in_progress) |
| locked = spin_trylock_irqsave(&port->lock, flags); |
| else |
| spin_lock_irqsave(&port->lock, flags); |
| |
| /* |
| * First save the IER then disable the interrupts |
| */ |
| ier = serial_port_in(port, UART_IER); |
| |
| if (up->capabilities & UART_CAP_UUE) |
| serial_port_out(port, UART_IER, UART_IER_UUE); |
| else |
| serial_port_out(port, UART_IER, 0); |
| |
| /* check scratch reg to see if port powered off during system sleep */ |
| if (up->canary && (up->canary != serial_port_in(port, UART_SCR))) { |
| serial8250_console_restore(up); |
| up->canary = 0; |
| } |
| |
| uart_console_write(port, s, count, serial8250_console_putchar); |
| |
| /* |
| * Finally, wait for transmitter to become empty |
| * and restore the IER |
| */ |
| wait_for_xmitr(up, BOTH_EMPTY); |
| serial_port_out(port, UART_IER, ier); |
| |
| /* |
| * The receive handling will happen properly because the |
| * receive ready bit will still be set; it is not cleared |
| * on read. However, modem control will not, we must |
| * call it if we have saved something in the saved flags |
| * while processing with interrupts off. |
| */ |
| if (up->msr_saved_flags) |
| serial8250_modem_status(up); |
| |
| if (locked) |
| spin_unlock_irqrestore(&port->lock, flags); |
| serial8250_rpm_put(up); |
| } |
| |
| static unsigned int probe_baud(struct uart_port *port) |
| { |
| unsigned char lcr, dll, dlm; |
| unsigned int quot; |
| |
| lcr = serial_port_in(port, UART_LCR); |
| serial_port_out(port, UART_LCR, lcr | UART_LCR_DLAB); |
| dll = serial_port_in(port, UART_DLL); |
| dlm = serial_port_in(port, UART_DLM); |
| serial_port_out(port, UART_LCR, lcr); |
| |
| quot = (dlm << 8) | dll; |
| return (port->uartclk / 16) / quot; |
| } |
| |
| int serial8250_console_setup(struct uart_port *port, char *options, bool probe) |
| { |
| int baud = 9600; |
| int bits = 8; |
| int parity = 'n'; |
| int flow = 'n'; |
| |
| if (!port->iobase && !port->membase) |
| return -ENODEV; |
| |
| if (options) |
| uart_parse_options(options, &baud, &parity, &bits, &flow); |
| else if (probe) |
| baud = probe_baud(port); |
| |
| return uart_set_options(port, port->cons, baud, parity, bits, flow); |
| } |
| |
| #endif /* CONFIG_SERIAL_8250_CONSOLE */ |
| |
| MODULE_LICENSE("GPL"); |