| /* SPDX-License-Identifier: GPL-2.0+ */ |
| /* |
| * Driver for 8250/16550-type serial ports |
| * |
| * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o. |
| * |
| * Copyright (C) 2001 Russell King. |
| */ |
| |
| #include <linux/bits.h> |
| #include <linux/serial_8250.h> |
| #include <linux/serial_reg.h> |
| #include <linux/dmaengine.h> |
| |
| #include "../serial_mctrl_gpio.h" |
| |
| struct uart_8250_dma { |
| int (*tx_dma)(struct uart_8250_port *p); |
| int (*rx_dma)(struct uart_8250_port *p); |
| void (*prepare_tx_dma)(struct uart_8250_port *p); |
| void (*prepare_rx_dma)(struct uart_8250_port *p); |
| |
| /* Filter function */ |
| dma_filter_fn fn; |
| /* Parameter to the filter function */ |
| void *rx_param; |
| void *tx_param; |
| |
| struct dma_slave_config rxconf; |
| struct dma_slave_config txconf; |
| |
| struct dma_chan *rxchan; |
| struct dma_chan *txchan; |
| |
| /* Device address base for DMA operations */ |
| phys_addr_t rx_dma_addr; |
| phys_addr_t tx_dma_addr; |
| |
| /* DMA address of the buffer in memory */ |
| dma_addr_t rx_addr; |
| dma_addr_t tx_addr; |
| |
| dma_cookie_t rx_cookie; |
| dma_cookie_t tx_cookie; |
| |
| void *rx_buf; |
| |
| size_t rx_size; |
| size_t tx_size; |
| |
| unsigned char tx_running; |
| unsigned char tx_err; |
| unsigned char rx_running; |
| }; |
| |
| struct old_serial_port { |
| unsigned int uart; |
| unsigned int baud_base; |
| unsigned int port; |
| unsigned int irq; |
| upf_t flags; |
| unsigned char io_type; |
| unsigned char __iomem *iomem_base; |
| unsigned short iomem_reg_shift; |
| }; |
| |
| struct serial8250_config { |
| const char *name; |
| unsigned short fifo_size; |
| unsigned short tx_loadsz; |
| unsigned char fcr; |
| unsigned char rxtrig_bytes[UART_FCR_R_TRIG_MAX_STATE]; |
| unsigned int flags; |
| }; |
| |
| #define UART_CAP_FIFO BIT(8) /* UART has FIFO */ |
| #define UART_CAP_EFR BIT(9) /* UART has EFR */ |
| #define UART_CAP_SLEEP BIT(10) /* UART has IER sleep */ |
| #define UART_CAP_AFE BIT(11) /* MCR-based hw flow control */ |
| #define UART_CAP_UUE BIT(12) /* UART needs IER bit 6 set (Xscale) */ |
| #define UART_CAP_RTOIE BIT(13) /* UART needs IER bit 4 set (Xscale, Tegra) */ |
| #define UART_CAP_HFIFO BIT(14) /* UART has a "hidden" FIFO */ |
| #define UART_CAP_RPM BIT(15) /* Runtime PM is active while idle */ |
| #define UART_CAP_IRDA BIT(16) /* UART supports IrDA line discipline */ |
| #define UART_CAP_MINI BIT(17) /* Mini UART on BCM283X family lacks: |
| * STOP PARITY EPAR SPAR WLEN5 WLEN6 |
| */ |
| #define UART_CAP_NOTEMT BIT(18) /* UART without interrupt on TEMT available */ |
| |
| #define UART_BUG_QUOT BIT(0) /* UART has buggy quot LSB */ |
| #define UART_BUG_TXEN BIT(1) /* UART has buggy TX IIR status */ |
| #define UART_BUG_NOMSR BIT(2) /* UART has buggy MSR status bits (Au1x00) */ |
| #define UART_BUG_THRE BIT(3) /* UART has buggy THRE reassertion */ |
| #define UART_BUG_PARITY BIT(4) /* UART mishandles parity if FIFO enabled */ |
| #define UART_BUG_TXRACE BIT(5) /* UART Tx fails to set remote DR */ |
| |
| |
| #ifdef CONFIG_SERIAL_8250_SHARE_IRQ |
| #define SERIAL8250_SHARE_IRQS 1 |
| #else |
| #define SERIAL8250_SHARE_IRQS 0 |
| #endif |
| |
| #define SERIAL8250_PORT_FLAGS(_base, _irq, _flags) \ |
| { \ |
| .iobase = _base, \ |
| .irq = _irq, \ |
| .uartclk = 1843200, \ |
| .iotype = UPIO_PORT, \ |
| .flags = UPF_BOOT_AUTOCONF | (_flags), \ |
| } |
| |
| #define SERIAL8250_PORT(_base, _irq) SERIAL8250_PORT_FLAGS(_base, _irq, 0) |
| |
| |
| static inline int serial_in(struct uart_8250_port *up, int offset) |
| { |
| return up->port.serial_in(&up->port, offset); |
| } |
| |
| static inline void serial_out(struct uart_8250_port *up, int offset, int value) |
| { |
| up->port.serial_out(&up->port, offset, value); |
| } |
| |
| /** |
| * serial_lsr_in - Read LSR register and preserve flags across reads |
| * @up: uart 8250 port |
| * |
| * Read LSR register and handle saving non-preserved flags across reads. |
| * The flags that are not preserved across reads are stored into |
| * up->lsr_saved_flags. |
| * |
| * Returns LSR value or'ed with the preserved flags (if any). |
| */ |
| static inline u16 serial_lsr_in(struct uart_8250_port *up) |
| { |
| u16 lsr = up->lsr_saved_flags; |
| |
| lsr |= serial_in(up, UART_LSR); |
| up->lsr_saved_flags = lsr & up->lsr_save_mask; |
| |
| return lsr; |
| } |
| |
| /* |
| * 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 __maybe_unused 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; |
| } |
| |
| void serial8250_clear_and_reinit_fifos(struct uart_8250_port *p); |
| |
| static inline int serial_dl_read(struct uart_8250_port *up) |
| { |
| return up->dl_read(up); |
| } |
| |
| static inline void serial_dl_write(struct uart_8250_port *up, int value) |
| { |
| up->dl_write(up, value); |
| } |
| |
| static inline bool serial8250_set_THRI(struct uart_8250_port *up) |
| { |
| if (up->ier & UART_IER_THRI) |
| return false; |
| up->ier |= UART_IER_THRI; |
| serial_out(up, UART_IER, up->ier); |
| return true; |
| } |
| |
| static inline bool serial8250_clear_THRI(struct uart_8250_port *up) |
| { |
| if (!(up->ier & UART_IER_THRI)) |
| return false; |
| up->ier &= ~UART_IER_THRI; |
| serial_out(up, UART_IER, up->ier); |
| return true; |
| } |
| |
| struct uart_8250_port *serial8250_get_port(int line); |
| |
| void serial8250_rpm_get(struct uart_8250_port *p); |
| void serial8250_rpm_put(struct uart_8250_port *p); |
| |
| void serial8250_rpm_get_tx(struct uart_8250_port *p); |
| void serial8250_rpm_put_tx(struct uart_8250_port *p); |
| |
| int serial8250_em485_config(struct uart_port *port, struct ktermios *termios, |
| struct serial_rs485 *rs485); |
| void serial8250_em485_start_tx(struct uart_8250_port *p); |
| void serial8250_em485_stop_tx(struct uart_8250_port *p); |
| void serial8250_em485_destroy(struct uart_8250_port *p); |
| extern struct serial_rs485 serial8250_em485_supported; |
| |
| /* MCR <-> TIOCM conversion */ |
| static inline int serial8250_TIOCM_to_MCR(int tiocm) |
| { |
| int mcr = 0; |
| |
| if (tiocm & TIOCM_RTS) |
| mcr |= UART_MCR_RTS; |
| if (tiocm & TIOCM_DTR) |
| mcr |= UART_MCR_DTR; |
| if (tiocm & TIOCM_OUT1) |
| mcr |= UART_MCR_OUT1; |
| if (tiocm & TIOCM_OUT2) |
| mcr |= UART_MCR_OUT2; |
| if (tiocm & TIOCM_LOOP) |
| mcr |= UART_MCR_LOOP; |
| |
| return mcr; |
| } |
| |
| static inline int serial8250_MCR_to_TIOCM(int mcr) |
| { |
| int tiocm = 0; |
| |
| if (mcr & UART_MCR_RTS) |
| tiocm |= TIOCM_RTS; |
| if (mcr & UART_MCR_DTR) |
| tiocm |= TIOCM_DTR; |
| if (mcr & UART_MCR_OUT1) |
| tiocm |= TIOCM_OUT1; |
| if (mcr & UART_MCR_OUT2) |
| tiocm |= TIOCM_OUT2; |
| if (mcr & UART_MCR_LOOP) |
| tiocm |= TIOCM_LOOP; |
| |
| return tiocm; |
| } |
| |
| /* MSR <-> TIOCM conversion */ |
| static inline int serial8250_MSR_to_TIOCM(int msr) |
| { |
| int tiocm = 0; |
| |
| if (msr & UART_MSR_DCD) |
| tiocm |= TIOCM_CAR; |
| if (msr & UART_MSR_RI) |
| tiocm |= TIOCM_RNG; |
| if (msr & UART_MSR_DSR) |
| tiocm |= TIOCM_DSR; |
| if (msr & UART_MSR_CTS) |
| tiocm |= TIOCM_CTS; |
| |
| return tiocm; |
| } |
| |
| static inline void serial8250_out_MCR(struct uart_8250_port *up, int value) |
| { |
| serial_out(up, UART_MCR, value); |
| |
| if (up->gpios) |
| mctrl_gpio_set(up->gpios, serial8250_MCR_to_TIOCM(value)); |
| } |
| |
| static inline int serial8250_in_MCR(struct uart_8250_port *up) |
| { |
| int mctrl; |
| |
| mctrl = serial_in(up, UART_MCR); |
| |
| if (up->gpios) { |
| unsigned int mctrl_gpio = 0; |
| |
| mctrl_gpio = mctrl_gpio_get_outputs(up->gpios, &mctrl_gpio); |
| mctrl |= serial8250_TIOCM_to_MCR(mctrl_gpio); |
| } |
| |
| return mctrl; |
| } |
| |
| bool alpha_jensen(void); |
| void alpha_jensen_set_mctrl(struct uart_port *port, unsigned int mctrl); |
| |
| #ifdef CONFIG_SERIAL_8250_PNP |
| int serial8250_pnp_init(void); |
| void serial8250_pnp_exit(void); |
| #else |
| static inline int serial8250_pnp_init(void) { return 0; } |
| static inline void serial8250_pnp_exit(void) { } |
| #endif |
| |
| #ifdef CONFIG_SERIAL_8250_FINTEK |
| int fintek_8250_probe(struct uart_8250_port *uart); |
| #else |
| static inline int fintek_8250_probe(struct uart_8250_port *uart) { return 0; } |
| #endif |
| |
| #ifdef CONFIG_ARCH_OMAP1 |
| #include <linux/soc/ti/omap1-soc.h> |
| static inline int is_omap1_8250(struct uart_8250_port *pt) |
| { |
| int res; |
| |
| switch (pt->port.mapbase) { |
| case OMAP1_UART1_BASE: |
| case OMAP1_UART2_BASE: |
| case OMAP1_UART3_BASE: |
| res = 1; |
| break; |
| default: |
| res = 0; |
| break; |
| } |
| |
| return res; |
| } |
| |
| static inline int is_omap1510_8250(struct uart_8250_port *pt) |
| { |
| if (!cpu_is_omap1510()) |
| return 0; |
| |
| return is_omap1_8250(pt); |
| } |
| #else |
| static inline int is_omap1_8250(struct uart_8250_port *pt) |
| { |
| return 0; |
| } |
| static inline int is_omap1510_8250(struct uart_8250_port *pt) |
| { |
| return 0; |
| } |
| #endif |
| |
| #ifdef CONFIG_SERIAL_8250_DMA |
| extern int serial8250_tx_dma(struct uart_8250_port *); |
| extern int serial8250_rx_dma(struct uart_8250_port *); |
| extern void serial8250_rx_dma_flush(struct uart_8250_port *); |
| extern int serial8250_request_dma(struct uart_8250_port *); |
| extern void serial8250_release_dma(struct uart_8250_port *); |
| |
| static inline void serial8250_do_prepare_tx_dma(struct uart_8250_port *p) |
| { |
| struct uart_8250_dma *dma = p->dma; |
| |
| if (dma->prepare_tx_dma) |
| dma->prepare_tx_dma(p); |
| } |
| |
| static inline void serial8250_do_prepare_rx_dma(struct uart_8250_port *p) |
| { |
| struct uart_8250_dma *dma = p->dma; |
| |
| if (dma->prepare_rx_dma) |
| dma->prepare_rx_dma(p); |
| } |
| #else |
| static inline int serial8250_tx_dma(struct uart_8250_port *p) |
| { |
| return -1; |
| } |
| static inline int serial8250_rx_dma(struct uart_8250_port *p) |
| { |
| return -1; |
| } |
| static inline void serial8250_rx_dma_flush(struct uart_8250_port *p) { } |
| static inline int serial8250_request_dma(struct uart_8250_port *p) |
| { |
| return -1; |
| } |
| static inline void serial8250_release_dma(struct uart_8250_port *p) { } |
| #endif |
| |
| static inline int ns16550a_goto_highspeed(struct uart_8250_port *up) |
| { |
| unsigned char status; |
| |
| status = serial_in(up, 0x04); /* EXCR2 */ |
| #define PRESL(x) ((x) & 0x30) |
| if (PRESL(status) == 0x10) { |
| /* already in high speed mode */ |
| return 0; |
| } else { |
| status &= ~0xB0; /* Disable LOCK, mask out PRESL[01] */ |
| status |= 0x10; /* 1.625 divisor for baud_base --> 921600 */ |
| serial_out(up, 0x04, status); |
| } |
| return 1; |
| } |
| |
| static inline int serial_index(struct uart_port *port) |
| { |
| return port->minor - 64; |
| } |