blob: 1aa3e55c8b47da2cdb93ef2e846a88d239a35369 [file] [log] [blame]
/* 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_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 u32 serial_dl_read(struct uart_8250_port *up)
{
return up->dl_read(up);
}
static inline void serial_dl_write(struct uart_8250_port *up, u32 value)
{
up->dl_write(up, value);
}
static inline bool serial8250_set_THRI(struct uart_8250_port *up)
{
/* Port locked to synchronize UART_IER access against the console. */
lockdep_assert_held_once(&up->port.lock);
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)
{
/* Port locked to synchronize UART_IER access against the console. */
lockdep_assert_held_once(&up->port.lock);
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);
}
static inline bool serial8250_tx_dma_running(struct uart_8250_port *p)
{
struct uart_8250_dma *dma = p->dma;
return dma && dma->tx_running;
}
#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) { }
static inline bool serial8250_tx_dma_running(struct uart_8250_port *p)
{
return false;
}
#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;
}