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linux/drivers/tty/serial/omap-serial.c
Lukas Wunner c150c0f362 serial: Allow uart_get_rs485_mode() to return errno 
We're about to amend uart_get_rs485_mode() to support a GPIO pin for
rs485 bus termination.  Retrieving the GPIO descriptor may fail, so
allow uart_get_rs485_mode() to return an errno and change all callers
to check for failure.

The GPIO descriptor is going to be stored in struct uart_port.  Pass
that struct to uart_get_rs485_mode() in lieu of a struct device and
struct serial_rs485, both of which are directly accessible from struct
uart_port.

A few drivers call uart_get_rs485_mode() before setting the struct
device pointer in struct uart_port.  Shuffle those calls around where
necessary.

[Heiko Stuebner did the ar933x_uart.c portion, hence his Signed-off-by.]

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/271e814af4b0db3bffbbb74abf2b46b75add4516.1589285873.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-15 14:47:05 +02:00

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// SPDX-License-Identifier: GPL-2.0+
/*
* Driver for OMAP-UART controller.
* Based on drivers/serial/8250.c
*
* Copyright (C) 2010 Texas Instruments.
*
* Authors:
* Govindraj R <govindraj.raja@ti.com>
* Thara Gopinath <thara@ti.com>
*
* Note: This driver is made separate from 8250 driver as we cannot
* over load 8250 driver with omap platform specific configuration for
* features like DMA, it makes easier to implement features like DMA and
* hardware flow control and software flow control configuration with
* this driver as required for the omap-platform.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/console.h>
#include <linux/serial_reg.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/clk.h>
#include <linux/serial_core.h>
#include <linux/irq.h>
#include <linux/pm_runtime.h>
#include <linux/pm_wakeirq.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/gpio/consumer.h>
#include <linux/platform_data/serial-omap.h>
#define OMAP_MAX_HSUART_PORTS 10
#define UART_BUILD_REVISION(x, y) (((x) << 8) | (y))
#define OMAP_UART_REV_42 0x0402
#define OMAP_UART_REV_46 0x0406
#define OMAP_UART_REV_52 0x0502
#define OMAP_UART_REV_63 0x0603
#define OMAP_UART_TX_WAKEUP_EN BIT(7)
/* Feature flags */
#define OMAP_UART_WER_HAS_TX_WAKEUP BIT(0)
#define UART_ERRATA_i202_MDR1_ACCESS BIT(0)
#define UART_ERRATA_i291_DMA_FORCEIDLE BIT(1)
#define DEFAULT_CLK_SPEED 48000000 /* 48Mhz */
/* SCR register bitmasks */
#define OMAP_UART_SCR_RX_TRIG_GRANU1_MASK (1 << 7)
#define OMAP_UART_SCR_TX_TRIG_GRANU1_MASK (1 << 6)
#define OMAP_UART_SCR_TX_EMPTY (1 << 3)
/* FCR register bitmasks */
#define OMAP_UART_FCR_RX_FIFO_TRIG_MASK (0x3 << 6)
#define OMAP_UART_FCR_TX_FIFO_TRIG_MASK (0x3 << 4)
/* MVR register bitmasks */
#define OMAP_UART_MVR_SCHEME_SHIFT 30
#define OMAP_UART_LEGACY_MVR_MAJ_MASK 0xf0
#define OMAP_UART_LEGACY_MVR_MAJ_SHIFT 4
#define OMAP_UART_LEGACY_MVR_MIN_MASK 0x0f
#define OMAP_UART_MVR_MAJ_MASK 0x700
#define OMAP_UART_MVR_MAJ_SHIFT 8
#define OMAP_UART_MVR_MIN_MASK 0x3f
#define OMAP_UART_DMA_CH_FREE -1
#define MSR_SAVE_FLAGS UART_MSR_ANY_DELTA
#define OMAP_MODE13X_SPEED 230400
/* WER = 0x7F
* Enable module level wakeup in WER reg
*/
#define OMAP_UART_WER_MOD_WKUP 0x7F
/* Enable XON/XOFF flow control on output */
#define OMAP_UART_SW_TX 0x08
/* Enable XON/XOFF flow control on input */
#define OMAP_UART_SW_RX 0x02
#define OMAP_UART_SW_CLR 0xF0
#define OMAP_UART_TCR_TRIG 0x0F
struct uart_omap_dma {
u8 uart_dma_tx;
u8 uart_dma_rx;
int rx_dma_channel;
int tx_dma_channel;
dma_addr_t rx_buf_dma_phys;
dma_addr_t tx_buf_dma_phys;
unsigned int uart_base;
/*
* Buffer for rx dma. It is not required for tx because the buffer
* comes from port structure.
*/
unsigned char *rx_buf;
unsigned int prev_rx_dma_pos;
int tx_buf_size;
int tx_dma_used;
int rx_dma_used;
spinlock_t tx_lock;
spinlock_t rx_lock;
/* timer to poll activity on rx dma */
struct timer_list rx_timer;
unsigned int rx_buf_size;
unsigned int rx_poll_rate;
unsigned int rx_timeout;
};
struct uart_omap_port {
struct uart_port port;
struct uart_omap_dma uart_dma;
struct device *dev;
int wakeirq;
unsigned char ier;
unsigned char lcr;
unsigned char mcr;
unsigned char fcr;
unsigned char efr;
unsigned char dll;
unsigned char dlh;
unsigned char mdr1;
unsigned char scr;
unsigned char wer;
int use_dma;
/*
* Some bits in registers are cleared on a read, so they must
* be saved whenever the register is read, but the bits will not
* be immediately processed.
*/
unsigned int lsr_break_flag;
unsigned char msr_saved_flags;
char name[20];
unsigned long port_activity;
int context_loss_cnt;
u32 errata;
u32 features;
struct gpio_desc *rts_gpiod;
struct pm_qos_request pm_qos_request;
u32 latency;
u32 calc_latency;
struct work_struct qos_work;
bool is_suspending;
};
#define to_uart_omap_port(p) ((container_of((p), struct uart_omap_port, port)))
static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
/* Forward declaration of functions */
static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1);
static inline unsigned int serial_in(struct uart_omap_port *up, int offset)
{
offset <<= up->port.regshift;
return readw(up->port.membase + offset);
}
static inline void serial_out(struct uart_omap_port *up, int offset, int value)
{
offset <<= up->port.regshift;
writew(value, up->port.membase + offset);
}
static inline void serial_omap_clear_fifos(struct uart_omap_port *up)
{
serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
serial_out(up, UART_FCR, 0);
}
#ifdef CONFIG_PM
static int serial_omap_get_context_loss_count(struct uart_omap_port *up)
{
struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
if (!pdata || !pdata->get_context_loss_count)
return -EINVAL;
return pdata->get_context_loss_count(up->dev);
}
/* REVISIT: Remove this when omap3 boots in device tree only mode */
static void serial_omap_enable_wakeup(struct uart_omap_port *up, bool enable)
{
struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
if (!pdata || !pdata->enable_wakeup)
return;
pdata->enable_wakeup(up->dev, enable);
}
#endif /* CONFIG_PM */
/*
* Calculate the absolute difference between the desired and actual baud
* rate for the given mode.
*/
static inline int calculate_baud_abs_diff(struct uart_port *port,
unsigned int baud, unsigned int mode)
{
unsigned int n = port->uartclk / (mode * baud);
int abs_diff;
if (n == 0)
n = 1;
abs_diff = baud - (port->uartclk / (mode * n));
if (abs_diff < 0)
abs_diff = -abs_diff;
return abs_diff;
}
/*
* serial_omap_baud_is_mode16 - check if baud rate is MODE16X
* @port: uart port info
* @baud: baudrate for which mode needs to be determined
*
* Returns true if baud rate is MODE16X and false if MODE13X
* Original table in OMAP TRM named "UART Mode Baud Rates, Divisor Values,
* and Error Rates" determines modes not for all common baud rates.
* E.g. for 1000000 baud rate mode must be 16x, but according to that
* table it's determined as 13x.
*/
static bool
serial_omap_baud_is_mode16(struct uart_port *port, unsigned int baud)
{
int abs_diff_13 = calculate_baud_abs_diff(port, baud, 13);
int abs_diff_16 = calculate_baud_abs_diff(port, baud, 16);
return (abs_diff_13 >= abs_diff_16);
}
/*
* serial_omap_get_divisor - calculate divisor value
* @port: uart port info
* @baud: baudrate for which divisor needs to be calculated.
*/
static unsigned int
serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
{
unsigned int mode;
if (!serial_omap_baud_is_mode16(port, baud))
mode = 13;
else
mode = 16;
return port->uartclk/(mode * baud);
}
static void serial_omap_enable_ms(struct uart_port *port)
{
struct uart_omap_port *up = to_uart_omap_port(port);
dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->port.line);
pm_runtime_get_sync(up->dev);
up->ier |= UART_IER_MSI;
serial_out(up, UART_IER, up->ier);
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);
}
static void serial_omap_stop_tx(struct uart_port *port)
{
struct uart_omap_port *up = to_uart_omap_port(port);
int res;
pm_runtime_get_sync(up->dev);
/* Handle RS-485 */
if (port->rs485.flags & SER_RS485_ENABLED) {
if (up->scr & OMAP_UART_SCR_TX_EMPTY) {
/* THR interrupt is fired when both TX FIFO and TX
* shift register are empty. This means there's nothing
* left to transmit now, so make sure the THR interrupt
* is fired when TX FIFO is below the trigger level,
* disable THR interrupts and toggle the RS-485 GPIO
* data direction pin if needed.
*/
up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
serial_out(up, UART_OMAP_SCR, up->scr);
res = (port->rs485.flags & SER_RS485_RTS_AFTER_SEND) ?
1 : 0;
if (gpiod_get_value(up->rts_gpiod) != res) {
if (port->rs485.delay_rts_after_send > 0)
mdelay(
port->rs485.delay_rts_after_send);
gpiod_set_value(up->rts_gpiod, res);
}
} else {
/* We're asked to stop, but there's still stuff in the
* UART FIFO, so make sure the THR interrupt is fired
* when both TX FIFO and TX shift register are empty.
* The next THR interrupt (if no transmission is started
* in the meantime) will indicate the end of a
* transmission. Therefore we _don't_ disable THR
* interrupts in this situation.
*/
up->scr |= OMAP_UART_SCR_TX_EMPTY;
serial_out(up, UART_OMAP_SCR, up->scr);
return;
}
}
if (up->ier & UART_IER_THRI) {
up->ier &= ~UART_IER_THRI;
serial_out(up, UART_IER, up->ier);
}
if ((port->rs485.flags & SER_RS485_ENABLED) &&
!(port->rs485.flags & SER_RS485_RX_DURING_TX)) {
/*
* Empty the RX FIFO, we are not interested in anything
* received during the half-duplex transmission.
*/
serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_RCVR);
/* Re-enable RX interrupts */
up->ier |= UART_IER_RLSI | UART_IER_RDI;
up->port.read_status_mask |= UART_LSR_DR;
serial_out(up, UART_IER, up->ier);
}
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);
}
static void serial_omap_stop_rx(struct uart_port *port)
{
struct uart_omap_port *up = to_uart_omap_port(port);
pm_runtime_get_sync(up->dev);
up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
up->port.read_status_mask &= ~UART_LSR_DR;
serial_out(up, UART_IER, up->ier);
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);
}
static void transmit_chars(struct uart_omap_port *up, unsigned int lsr)
{
struct circ_buf *xmit = &up->port.state->xmit;
int count;
if (up->port.x_char) {
serial_out(up, UART_TX, up->port.x_char);
up->port.icount.tx++;
up->port.x_char = 0;
return;
}
if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
serial_omap_stop_tx(&up->port);
return;
}
count = up->port.fifosize / 4;
do {
serial_out(up, UART_TX, xmit->buf[xmit->tail]);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
up->port.icount.tx++;
if (uart_circ_empty(xmit))
break;
} while (--count > 0);
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(&up->port);
if (uart_circ_empty(xmit))
serial_omap_stop_tx(&up->port);
}
static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up)
{
if (!(up->ier & UART_IER_THRI)) {
up->ier |= UART_IER_THRI;
serial_out(up, UART_IER, up->ier);
}
}
static void serial_omap_start_tx(struct uart_port *port)
{
struct uart_omap_port *up = to_uart_omap_port(port);
int res;
pm_runtime_get_sync(up->dev);
/* Handle RS-485 */
if (port->rs485.flags & SER_RS485_ENABLED) {
/* Fire THR interrupts when FIFO is below trigger level */
up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
serial_out(up, UART_OMAP_SCR, up->scr);
/* if rts not already enabled */
res = (port->rs485.flags & SER_RS485_RTS_ON_SEND) ? 1 : 0;
if (gpiod_get_value(up->rts_gpiod) != res) {
gpiod_set_value(up->rts_gpiod, res);
if (port->rs485.delay_rts_before_send > 0)
mdelay(port->rs485.delay_rts_before_send);
}
}
if ((port->rs485.flags & SER_RS485_ENABLED) &&
!(port->rs485.flags & SER_RS485_RX_DURING_TX))
serial_omap_stop_rx(port);
serial_omap_enable_ier_thri(up);
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);
}
static void serial_omap_throttle(struct uart_port *port)
{
struct uart_omap_port *up = to_uart_omap_port(port);
unsigned long flags;
pm_runtime_get_sync(up->dev);
spin_lock_irqsave(&up->port.lock, flags);
up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
serial_out(up, UART_IER, up->ier);
spin_unlock_irqrestore(&up->port.lock, flags);
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);
}
static void serial_omap_unthrottle(struct uart_port *port)
{
struct uart_omap_port *up = to_uart_omap_port(port);
unsigned long flags;
pm_runtime_get_sync(up->dev);
spin_lock_irqsave(&up->port.lock, flags);
up->ier |= UART_IER_RLSI | UART_IER_RDI;
serial_out(up, UART_IER, up->ier);
spin_unlock_irqrestore(&up->port.lock, flags);
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);
}
static unsigned int check_modem_status(struct uart_omap_port *up)
{
unsigned int status;
status = serial_in(up, UART_MSR);
status |= up->msr_saved_flags;
up->msr_saved_flags = 0;
if ((status & UART_MSR_ANY_DELTA) == 0)
return status;
if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
up->port.state != NULL) {
if (status & UART_MSR_TERI)
up->port.icount.rng++;
if (status & UART_MSR_DDSR)
up->port.icount.dsr++;
if (status & UART_MSR_DDCD)
uart_handle_dcd_change
(&up->port, status & UART_MSR_DCD);
if (status & UART_MSR_DCTS)
uart_handle_cts_change
(&up->port, status & UART_MSR_CTS);
wake_up_interruptible(&up->port.state->port.delta_msr_wait);
}
return status;
}
static void serial_omap_rlsi(struct uart_omap_port *up, unsigned int lsr)
{
unsigned int flag;
/*
* Read one data character out to avoid stalling the receiver according
* to the table 23-246 of the omap4 TRM.
*/
if (likely(lsr & UART_LSR_DR))
serial_in(up, UART_RX);
up->port.icount.rx++;
flag = TTY_NORMAL;
if (lsr & UART_LSR_BI) {
flag = TTY_BREAK;
lsr &= ~(UART_LSR_FE | UART_LSR_PE);
up->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(&up->port))
return;
}
if (lsr & UART_LSR_PE) {
flag = TTY_PARITY;
up->port.icount.parity++;
}
if (lsr & UART_LSR_FE) {
flag = TTY_FRAME;
up->port.icount.frame++;
}
if (lsr & UART_LSR_OE)
up->port.icount.overrun++;
#ifdef CONFIG_SERIAL_OMAP_CONSOLE
if (up->port.line == up->port.cons->index) {
/* Recover the break flag from console xmit */
lsr |= up->lsr_break_flag;
}
#endif
uart_insert_char(&up->port, lsr, UART_LSR_OE, 0, flag);
}
static void serial_omap_rdi(struct uart_omap_port *up, unsigned int lsr)
{
unsigned char ch = 0;
unsigned int flag;
if (!(lsr & UART_LSR_DR))
return;
ch = serial_in(up, UART_RX);
flag = TTY_NORMAL;
up->port.icount.rx++;
if (uart_handle_sysrq_char(&up->port, ch))
return;
uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag);
}
/**
* serial_omap_irq() - This handles the interrupt from one port
* @irq: uart port irq number
* @dev_id: uart port info
*/
static irqreturn_t serial_omap_irq(int irq, void *dev_id)
{
struct uart_omap_port *up = dev_id;
unsigned int iir, lsr;
unsigned int type;
irqreturn_t ret = IRQ_NONE;
int max_count = 256;
spin_lock(&up->port.lock);
pm_runtime_get_sync(up->dev);
do {
iir = serial_in(up, UART_IIR);
if (iir & UART_IIR_NO_INT)
break;
ret = IRQ_HANDLED;
lsr = serial_in(up, UART_LSR);
/* extract IRQ type from IIR register */
type = iir & 0x3e;
switch (type) {
case UART_IIR_MSI:
check_modem_status(up);
break;
case UART_IIR_THRI:
transmit_chars(up, lsr);
break;
case UART_IIR_RX_TIMEOUT:
/* FALLTHROUGH */
case UART_IIR_RDI:
serial_omap_rdi(up, lsr);
break;
case UART_IIR_RLSI:
serial_omap_rlsi(up, lsr);
break;
case UART_IIR_CTS_RTS_DSR:
/* simply try again */
break;
case UART_IIR_XOFF:
/* FALLTHROUGH */
default:
break;
}
} while (max_count--);
spin_unlock(&up->port.lock);
tty_flip_buffer_push(&up->port.state->port);
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);
up->port_activity = jiffies;
return ret;
}
static unsigned int serial_omap_tx_empty(struct uart_port *port)
{
struct uart_omap_port *up = to_uart_omap_port(port);
unsigned long flags = 0;
unsigned int ret = 0;
pm_runtime_get_sync(up->dev);
dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->port.line);
spin_lock_irqsave(&up->port.lock, flags);
ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
spin_unlock_irqrestore(&up->port.lock, flags);
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);
return ret;
}
static unsigned int serial_omap_get_mctrl(struct uart_port *port)
{
struct uart_omap_port *up = to_uart_omap_port(port);
unsigned int status;
unsigned int ret = 0;
pm_runtime_get_sync(up->dev);
status = check_modem_status(up);
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);
dev_dbg(up->port.dev, "serial_omap_get_mctrl+%d\n", up->port.line);
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;
}
static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
struct uart_omap_port *up = to_uart_omap_port(port);
unsigned char mcr = 0, old_mcr, lcr;
dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->port.line);
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;
pm_runtime_get_sync(up->dev);
old_mcr = serial_in(up, UART_MCR);
old_mcr &= ~(UART_MCR_LOOP | UART_MCR_OUT2 | UART_MCR_OUT1 |
UART_MCR_DTR | UART_MCR_RTS);
up->mcr = old_mcr | mcr;
serial_out(up, UART_MCR, up->mcr);
/* Turn off autoRTS if RTS is lowered; restore autoRTS if RTS raised */
lcr = serial_in(up, UART_LCR);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
if ((mctrl & TIOCM_RTS) && (port->status & UPSTAT_AUTORTS))
up->efr |= UART_EFR_RTS;
else
up->efr &= ~UART_EFR_RTS;
serial_out(up, UART_EFR, up->efr);
serial_out(up, UART_LCR, lcr);
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);
}
static void serial_omap_break_ctl(struct uart_port *port, int break_state)
{
struct uart_omap_port *up = to_uart_omap_port(port);
unsigned long flags = 0;
dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->port.line);
pm_runtime_get_sync(up->dev);
spin_lock_irqsave(&up->port.lock, flags);
if (break_state == -1)
up->lcr |= UART_LCR_SBC;
else
up->lcr &= ~UART_LCR_SBC;
serial_out(up, UART_LCR, up->lcr);
spin_unlock_irqrestore(&up->port.lock, flags);
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);
}
static int serial_omap_startup(struct uart_port *port)
{
struct uart_omap_port *up = to_uart_omap_port(port);
unsigned long flags = 0;
int retval;
/*
* Allocate the IRQ
*/
retval = request_irq(up->port.irq, serial_omap_irq, up->port.irqflags,
up->name, up);
if (retval)
return retval;
/* Optional wake-up IRQ */
if (up->wakeirq) {
retval = dev_pm_set_dedicated_wake_irq(up->dev, up->wakeirq);
if (retval) {
free_irq(up->port.irq, up);
return retval;
}
}
dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->port.line);
pm_runtime_get_sync(up->dev);
/*
* Clear the FIFO buffers and disable them.
* (they will be reenabled in set_termios())
*/
serial_omap_clear_fifos(up);
/*
* Clear the interrupt registers.
*/
(void) serial_in(up, UART_LSR);
if (serial_in(up, UART_LSR) & UART_LSR_DR)
(void) serial_in(up, UART_RX);
(void) serial_in(up, UART_IIR);
(void) serial_in(up, UART_MSR);
/*
* Now, initialize the UART
*/
serial_out(up, UART_LCR, UART_LCR_WLEN8);
spin_lock_irqsave(&up->port.lock, flags);
/*
* Most PC uarts need OUT2 raised to enable interrupts.
*/
up->port.mctrl |= TIOCM_OUT2;
serial_omap_set_mctrl(&up->port, up->port.mctrl);
spin_unlock_irqrestore(&up->port.lock, flags);
up->msr_saved_flags = 0;
/*
* Finally, enable interrupts. Note: Modem status interrupts
* are set via set_termios(), which will be occurring imminently
* anyway, so we don't enable them here.
*/
up->ier = UART_IER_RLSI | UART_IER_RDI;
serial_out(up, UART_IER, up->ier);
/* Enable module level wake up */
up->wer = OMAP_UART_WER_MOD_WKUP;
if (up->features & OMAP_UART_WER_HAS_TX_WAKEUP)
up->wer |= OMAP_UART_TX_WAKEUP_EN;
serial_out(up, UART_OMAP_WER, up->wer);
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);
up->port_activity = jiffies;
return 0;
}
static void serial_omap_shutdown(struct uart_port *port)
{
struct uart_omap_port *up = to_uart_omap_port(port);
unsigned long flags = 0;
dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->port.line);
pm_runtime_get_sync(up->dev);
/*
* Disable interrupts from this port
*/
up->ier = 0;
serial_out(up, UART_IER, 0);
spin_lock_irqsave(&up->port.lock, flags);
up->port.mctrl &= ~TIOCM_OUT2;
serial_omap_set_mctrl(&up->port, up->port.mctrl);
spin_unlock_irqrestore(&up->port.lock, flags);
/*
* Disable break condition and FIFOs
*/
serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
serial_omap_clear_fifos(up);
/*
* Read data port to reset things, and then free the irq
*/
if (serial_in(up, UART_LSR) & UART_LSR_DR)
(void) serial_in(up, UART_RX);
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);
free_irq(up->port.irq, up);
dev_pm_clear_wake_irq(up->dev);
}
static void serial_omap_uart_qos_work(struct work_struct *work)
{
struct uart_omap_port *up = container_of(work, struct uart_omap_port,
qos_work);
cpu_latency_qos_update_request(&up->pm_qos_request, up->latency);
}
static void
serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
struct ktermios *old)
{
struct uart_omap_port *up = to_uart_omap_port(port);
unsigned char cval = 0;
unsigned long flags = 0;
unsigned int baud, quot;
switch (termios->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 (termios->c_cflag & CSTOPB)
cval |= UART_LCR_STOP;
if (termios->c_cflag & PARENB)
cval |= UART_LCR_PARITY;
if (!(termios->c_cflag & PARODD))
cval |= UART_LCR_EPAR;
if (termios->c_cflag & CMSPAR)
cval |= UART_LCR_SPAR;
/*
* Ask the core to calculate the divisor for us.
*/
baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13);
quot = serial_omap_get_divisor(port, baud);
/* calculate wakeup latency constraint */
up->calc_latency = (USEC_PER_SEC * up->port.fifosize) / (baud / 8);
up->latency = up->calc_latency;
schedule_work(&up->qos_work);
up->dll = quot & 0xff;
up->dlh = quot >> 8;
up->mdr1 = UART_OMAP_MDR1_DISABLE;
up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 |
UART_FCR_ENABLE_FIFO;
/*
* Ok, we're now changing the port state. Do it with
* interrupts disabled.
*/
pm_runtime_get_sync(up->dev);
spin_lock_irqsave(&up->port.lock, flags);
/*
* Update the per-port timeout.
*/
uart_update_timeout(port, termios->c_cflag, baud);
up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
if (termios->c_iflag & INPCK)
up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
if (termios->c_iflag & (BRKINT | PARMRK))
up->port.read_status_mask |= UART_LSR_BI;
/*
* Characters to ignore
*/
up->port.ignore_status_mask = 0;
if (termios->c_iflag & IGNPAR)
up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
if (termios->c_iflag & IGNBRK) {
up->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)
up->port.ignore_status_mask |= UART_LSR_OE;
}
/*
* ignore all characters if CREAD is not set
*/
if ((termios->c_cflag & CREAD) == 0)
up->port.ignore_status_mask |= UART_LSR_DR;
/*
* Modem status interrupts
*/
up->ier &= ~UART_IER_MSI;
if (UART_ENABLE_MS(&up->port, termios->c_cflag))
up->ier |= UART_IER_MSI;
serial_out(up, UART_IER, up->ier);
serial_out(up, UART_LCR, cval); /* reset DLAB */
up->lcr = cval;
up->scr = 0;
/* FIFOs and DMA Settings */
/* FCR can be changed only when the
* baud clock is not running
* DLL_REG and DLH_REG set to 0.
*/
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
serial_out(up, UART_DLL, 0);
serial_out(up, UART_DLM, 0);
serial_out(up, UART_LCR, 0);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
up->efr = serial_in(up, UART_EFR) & ~UART_EFR_ECB;
up->efr &= ~UART_EFR_SCD;
serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
up->mcr = serial_in(up, UART_MCR) & ~UART_MCR_TCRTLR;
serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
/* FIFO ENABLE, DMA MODE */
up->scr |= OMAP_UART_SCR_RX_TRIG_GRANU1_MASK;
/*
* NOTE: Setting OMAP_UART_SCR_RX_TRIG_GRANU1_MASK
* sets Enables the granularity of 1 for TRIGGER RX
* level. Along with setting RX FIFO trigger level
* to 1 (as noted below, 16 characters) and TLR[3:0]
* to zero this will result RX FIFO threshold level
* to 1 character, instead of 16 as noted in comment
* below.
*/
/* Set receive FIFO threshold to 16 characters and
* transmit FIFO threshold to 32 spaces
*/
up->fcr &= ~OMAP_UART_FCR_RX_FIFO_TRIG_MASK;
up->fcr &= ~OMAP_UART_FCR_TX_FIFO_TRIG_MASK;
up->fcr |= UART_FCR6_R_TRIGGER_16 | UART_FCR6_T_TRIGGER_24 |
UART_FCR_ENABLE_FIFO;
serial_out(up, UART_FCR, up->fcr);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
serial_out(up, UART_OMAP_SCR, up->scr);
/* Reset UART_MCR_TCRTLR: this must be done with the EFR_ECB bit set */
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
serial_out(up, UART_MCR, up->mcr);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
serial_out(up, UART_EFR, up->efr);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
/* Protocol, Baud Rate, and Interrupt Settings */
if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
serial_omap_mdr1_errataset(up, up->mdr1);
else
serial_out(up, UART_OMAP_MDR1, up->mdr1);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
serial_out(up, UART_LCR, 0);
serial_out(up, UART_IER, 0);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
serial_out(up, UART_DLL, up->dll); /* LS of divisor */
serial_out(up, UART_DLM, up->dlh); /* MS of divisor */
serial_out(up, UART_LCR, 0);
serial_out(up, UART_IER, up->ier);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
serial_out(up, UART_EFR, up->efr);
serial_out(up, UART_LCR, cval);
if (!serial_omap_baud_is_mode16(port, baud))
up->mdr1 = UART_OMAP_MDR1_13X_MODE;
else
up->mdr1 = UART_OMAP_MDR1_16X_MODE;
if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
serial_omap_mdr1_errataset(up, up->mdr1);
else
serial_out(up, UART_OMAP_MDR1, up->mdr1);
/* Configure flow control */
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
/* XON1/XOFF1 accessible mode B, TCRTLR=0, ECB=0 */
serial_out(up, UART_XON1, termios->c_cc[VSTART]);
serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
/* Enable access to TCR/TLR */
serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
up->port.status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS | UPSTAT_AUTOXOFF);
if (termios->c_cflag & CRTSCTS && up->port.flags & UPF_HARD_FLOW) {
/* Enable AUTOCTS (autoRTS is enabled when RTS is raised) */
up->port.status |= UPSTAT_AUTOCTS | UPSTAT_AUTORTS;
up->efr |= UART_EFR_CTS;
} else {
/* Disable AUTORTS and AUTOCTS */
up->efr &= ~(UART_EFR_CTS | UART_EFR_RTS);
}
if (up->port.flags & UPF_SOFT_FLOW) {
/* clear SW control mode bits */
up->efr &= OMAP_UART_SW_CLR;
/*
* IXON Flag:
* Enable XON/XOFF flow control on input.
* Receiver compares XON1, XOFF1.
*/
if (termios->c_iflag & IXON)
up->efr |= OMAP_UART_SW_RX;
/*
* IXOFF Flag:
* Enable XON/XOFF flow control on output.
* Transmit XON1, XOFF1
*/
if (termios->c_iflag & IXOFF) {
up->port.status |= UPSTAT_AUTOXOFF;
up->efr |= OMAP_UART_SW_TX;
}
/*
* IXANY Flag:
* Enable any character to restart output.
* Operation resumes after receiving any
* character after recognition of the XOFF character
*/
if (termios->c_iflag & IXANY)
up->mcr |= UART_MCR_XONANY;
else
up->mcr &= ~UART_MCR_XONANY;
}
serial_out(up, UART_MCR, up->mcr);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
serial_out(up, UART_EFR, up->efr);
serial_out(up, UART_LCR, up->lcr);
serial_omap_set_mctrl(&up->port, up->port.mctrl);
spin_unlock_irqrestore(&up->port.lock, flags);
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);
dev_dbg(up->port.dev, "serial_omap_set_termios+%d\n", up->port.line);
}
static void
serial_omap_pm(struct uart_port *port, unsigned int state,
unsigned int oldstate)
{
struct uart_omap_port *up = to_uart_omap_port(port);
unsigned char efr;
dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->port.line);
pm_runtime_get_sync(up->dev);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
efr = serial_in(up, UART_EFR);
serial_out(up, UART_EFR, efr | UART_EFR_ECB);
serial_out(up, UART_LCR, 0);
serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
serial_out(up, UART_EFR, efr);
serial_out(up, UART_LCR, 0);
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);
}
static void serial_omap_release_port(struct uart_port *port)
{
dev_dbg(port->dev, "serial_omap_release_port+\n");
}
static int serial_omap_request_port(struct uart_port *port)
{
dev_dbg(port->dev, "serial_omap_request_port+\n");
return 0;
}
static void serial_omap_config_port(struct uart_port *port, int flags)
{
struct uart_omap_port *up = to_uart_omap_port(port);
dev_dbg(up->port.dev, "serial_omap_config_port+%d\n",
up->port.line);
up->port.type = PORT_OMAP;
up->port.flags |= UPF_SOFT_FLOW | UPF_HARD_FLOW;
}
static int
serial_omap_verify_port(struct uart_port *port, struct serial_struct *ser)
{
/* we don't want the core code to modify any port params */
dev_dbg(port->dev, "serial_omap_verify_port+\n");
return -EINVAL;
}
static const char *
serial_omap_type(struct uart_port *port)
{
struct uart_omap_port *up = to_uart_omap_port(port);
dev_dbg(up->port.dev, "serial_omap_type+%d\n", up->port.line);
return up->name;
}
#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
static void __maybe_unused wait_for_xmitr(struct uart_omap_port *up)
{
unsigned int status, tmout = 10000;
/* Wait up to 10ms for the character(s) to be sent. */
do {
status = serial_in(up, UART_LSR);
if (status & UART_LSR_BI)
up->lsr_break_flag = UART_LSR_BI;
if (--tmout == 0)
break;
udelay(1);
} while ((status & BOTH_EMPTY) != BOTH_EMPTY);
/* Wait up to 1s for flow control if necessary */
if (up->port.flags & UPF_CONS_FLOW) {
tmout = 1000000;
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);
}
}
}
#ifdef CONFIG_CONSOLE_POLL
static void serial_omap_poll_put_char(struct uart_port *port, unsigned char ch)
{
struct uart_omap_port *up = to_uart_omap_port(port);
pm_runtime_get_sync(up->dev);
wait_for_xmitr(up);
serial_out(up, UART_TX, ch);
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);
}
static int serial_omap_poll_get_char(struct uart_port *port)
{
struct uart_omap_port *up = to_uart_omap_port(port);
unsigned int status;
pm_runtime_get_sync(up->dev);
status = serial_in(up, UART_LSR);
if (!(status & UART_LSR_DR)) {
status = NO_POLL_CHAR;
goto out;
}
status = serial_in(up, UART_RX);
out:
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);
return status;
}
#endif /* CONFIG_CONSOLE_POLL */
#ifdef CONFIG_SERIAL_OMAP_CONSOLE
#ifdef CONFIG_SERIAL_EARLYCON
static unsigned int omap_serial_early_in(struct uart_port *port, int offset)
{
offset <<= port->regshift;
return readw(port->membase + offset);
}
static void omap_serial_early_out(struct uart_port *port, int offset,
int value)
{
offset <<= port->regshift;
writew(value, port->membase + offset);
}
static void omap_serial_early_putc(struct uart_port *port, int c)
{
unsigned int status;
for (;;) {
status = omap_serial_early_in(port, UART_LSR);
if ((status & BOTH_EMPTY) == BOTH_EMPTY)
break;
cpu_relax();
}
omap_serial_early_out(port, UART_TX, c);
}
static void early_omap_serial_write(struct console *console, const char *s,
unsigned int count)
{
struct earlycon_device *device = console->data;
struct uart_port *port = &device->port;
uart_console_write(port, s, count, omap_serial_early_putc);
}
static int __init early_omap_serial_setup(struct earlycon_device *device,
const char *options)
{
struct uart_port *port = &device->port;
if (!(device->port.membase || device->port.iobase))
return -ENODEV;
port->regshift = 2;
device->con->write = early_omap_serial_write;
return 0;
}
OF_EARLYCON_DECLARE(omapserial, "ti,omap2-uart", early_omap_serial_setup);
OF_EARLYCON_DECLARE(omapserial, "ti,omap3-uart", early_omap_serial_setup);
OF_EARLYCON_DECLARE(omapserial, "ti,omap4-uart", early_omap_serial_setup);
#endif /* CONFIG_SERIAL_EARLYCON */
static struct uart_omap_port *serial_omap_console_ports[OMAP_MAX_HSUART_PORTS];
static struct uart_driver serial_omap_reg;
static void serial_omap_console_putchar(struct uart_port *port, int ch)
{
struct uart_omap_port *up = to_uart_omap_port(port);
wait_for_xmitr(up);
serial_out(up, UART_TX, ch);
}
static void
serial_omap_console_write(struct console *co, const char *s,
unsigned int count)
{
struct uart_omap_port *up = serial_omap_console_ports[co->index];
unsigned long flags;
unsigned int ier;
int locked = 1;
pm_runtime_get_sync(up->dev);
local_irq_save(flags);
if (up->port.sysrq)
locked = 0;
else if (oops_in_progress)
locked = spin_trylock(&up->port.lock);
else
spin_lock(&up->port.lock);
/*
* First save the IER then disable the interrupts
*/
ier = serial_in(up, UART_IER);
serial_out(up, UART_IER, 0);
uart_console_write(&up->port, s, count, serial_omap_console_putchar);
/*
* Finally, wait for transmitter to become empty
* and restore the IER
*/
wait_for_xmitr(up);
serial_out(up, 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)
check_modem_status(up);
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);
if (locked)
spin_unlock(&up->port.lock);
local_irq_restore(flags);
}
static int __init
serial_omap_console_setup(struct console *co, char *options)
{
struct uart_omap_port *up;
int baud = 115200;
int bits = 8;
int parity = 'n';
int flow = 'n';
if (serial_omap_console_ports[co->index] == NULL)
return -ENODEV;
up = serial_omap_console_ports[co->index];
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
return uart_set_options(&up->port, co, baud, parity, bits, flow);
}
static struct console serial_omap_console = {
.name = OMAP_SERIAL_NAME,
.write = serial_omap_console_write,
.device = uart_console_device,
.setup = serial_omap_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
.data = &serial_omap_reg,
};
static void serial_omap_add_console_port(struct uart_omap_port *up)
{
serial_omap_console_ports[up->port.line] = up;
}
#define OMAP_CONSOLE (&serial_omap_console)
#else
#define OMAP_CONSOLE NULL
static inline void serial_omap_add_console_port(struct uart_omap_port *up)
{}
#endif
/* Enable or disable the rs485 support */
static int
serial_omap_config_rs485(struct uart_port *port, struct serial_rs485 *rs485)
{
struct uart_omap_port *up = to_uart_omap_port(port);
unsigned int mode;
int val;
pm_runtime_get_sync(up->dev);
/* Disable interrupts from this port */
mode = up->ier;
up->ier = 0;
serial_out(up, UART_IER, 0);
/* Clamp the delays to [0, 100ms] */
rs485->delay_rts_before_send = min(rs485->delay_rts_before_send, 100U);
rs485->delay_rts_after_send = min(rs485->delay_rts_after_send, 100U);
/* store new config */
port->rs485 = *rs485;
/*
* Just as a precaution, only allow rs485
* to be enabled if the gpio pin is valid
*/
if (up->rts_gpiod) {
/* enable / disable rts */
val = (port->rs485.flags & SER_RS485_ENABLED) ?
SER_RS485_RTS_AFTER_SEND : SER_RS485_RTS_ON_SEND;
val = (port->rs485.flags & val) ? 1 : 0;
gpiod_set_value(up->rts_gpiod, val);
} else
port->rs485.flags &= ~SER_RS485_ENABLED;
/* Enable interrupts */
up->ier = mode;
serial_out(up, UART_IER, up->ier);
/* If RS-485 is disabled, make sure the THR interrupt is fired when
* TX FIFO is below the trigger level.
*/
if (!(port->rs485.flags & SER_RS485_ENABLED) &&
(up->scr & OMAP_UART_SCR_TX_EMPTY)) {
up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
serial_out(up, UART_OMAP_SCR, up->scr);
}
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);
return 0;
}
static const struct uart_ops serial_omap_pops = {
.tx_empty = serial_omap_tx_empty,
.set_mctrl = serial_omap_set_mctrl,
.get_mctrl = serial_omap_get_mctrl,
.stop_tx = serial_omap_stop_tx,
.start_tx = serial_omap_start_tx,
.throttle = serial_omap_throttle,
.unthrottle = serial_omap_unthrottle,
.stop_rx = serial_omap_stop_rx,
.enable_ms = serial_omap_enable_ms,
.break_ctl = serial_omap_break_ctl,
.startup = serial_omap_startup,
.shutdown = serial_omap_shutdown,
.set_termios = serial_omap_set_termios,
.pm = serial_omap_pm,
.type = serial_omap_type,
.release_port = serial_omap_release_port,
.request_port = serial_omap_request_port,
.config_port = serial_omap_config_port,
.verify_port = serial_omap_verify_port,
#ifdef CONFIG_CONSOLE_POLL
.poll_put_char = serial_omap_poll_put_char,
.poll_get_char = serial_omap_poll_get_char,
#endif
};
static struct uart_driver serial_omap_reg = {
.owner = THIS_MODULE,
.driver_name = "OMAP-SERIAL",
.dev_name = OMAP_SERIAL_NAME,
.nr = OMAP_MAX_HSUART_PORTS,
.cons = OMAP_CONSOLE,
};
#ifdef CONFIG_PM_SLEEP
static int serial_omap_prepare(struct device *dev)
{
struct uart_omap_port *up = dev_get_drvdata(dev);
up->is_suspending = true;
return 0;
}
static void serial_omap_complete(struct device *dev)
{
struct uart_omap_port *up = dev_get_drvdata(dev);
up->is_suspending = false;
}
static int serial_omap_suspend(struct device *dev)
{
struct uart_omap_port *up = dev_get_drvdata(dev);
uart_suspend_port(&serial_omap_reg, &up->port);
flush_work(&up->qos_work);
if (device_may_wakeup(dev))
serial_omap_enable_wakeup(up, true);
else
serial_omap_enable_wakeup(up, false);
return 0;
}
static int serial_omap_resume(struct device *dev)
{
struct uart_omap_port *up = dev_get_drvdata(dev);
if (device_may_wakeup(dev))
serial_omap_enable_wakeup(up, false);
uart_resume_port(&serial_omap_reg, &up->port);
return 0;
}
#else
#define serial_omap_prepare NULL
#define serial_omap_complete NULL
#endif /* CONFIG_PM_SLEEP */
static void omap_serial_fill_features_erratas(struct uart_omap_port *up)
{
u32 mvr, scheme;
u16 revision, major, minor;
mvr = readl(up->port.membase + (UART_OMAP_MVER << up->port.regshift));
/* Check revision register scheme */
scheme = mvr >> OMAP_UART_MVR_SCHEME_SHIFT;
switch (scheme) {
case 0: /* Legacy Scheme: OMAP2/3 */
/* MINOR_REV[0:4], MAJOR_REV[4:7] */
major = (mvr & OMAP_UART_LEGACY_MVR_MAJ_MASK) >>
OMAP_UART_LEGACY_MVR_MAJ_SHIFT;
minor = (mvr & OMAP_UART_LEGACY_MVR_MIN_MASK);
break;
case 1:
/* New Scheme: OMAP4+ */
/* MINOR_REV[0:5], MAJOR_REV[8:10] */
major = (mvr & OMAP_UART_MVR_MAJ_MASK) >>
OMAP_UART_MVR_MAJ_SHIFT;
minor = (mvr & OMAP_UART_MVR_MIN_MASK);
break;
default:
dev_warn(up->dev,
"Unknown %s revision, defaulting to highest\n",
up->name);
/* highest possible revision */
major = 0xff;
minor = 0xff;
}
/* normalize revision for the driver */
revision = UART_BUILD_REVISION(major, minor);
switch (revision) {
case OMAP_UART_REV_46:
up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
UART_ERRATA_i291_DMA_FORCEIDLE);
break;
case OMAP_UART_REV_52:
up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
UART_ERRATA_i291_DMA_FORCEIDLE);
up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
break;
case OMAP_UART_REV_63:
up->errata |= UART_ERRATA_i202_MDR1_ACCESS;
up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
break;
default:
break;
}
}
static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev)
{
struct omap_uart_port_info *omap_up_info;
omap_up_info = devm_kzalloc(dev, sizeof(*omap_up_info), GFP_KERNEL);
if (!omap_up_info)
return NULL; /* out of memory */
of_property_read_u32(dev->of_node, "clock-frequency",
&omap_up_info->uartclk);
omap_up_info->flags = UPF_BOOT_AUTOCONF;
return omap_up_info;
}
static int serial_omap_probe_rs485(struct uart_omap_port *up,
struct device *dev)
{
struct serial_rs485 *rs485conf = &up->port.rs485;
struct device_node *np = dev->of_node;
enum gpiod_flags gflags;
int ret;
rs485conf->flags = 0;
up->rts_gpiod = NULL;
if (!np)
return 0;
ret = uart_get_rs485_mode(&up->port);
if (ret)
return ret;
if (of_property_read_bool(np, "rs485-rts-active-high")) {
rs485conf->flags |= SER_RS485_RTS_ON_SEND;
rs485conf->flags &= ~SER_RS485_RTS_AFTER_SEND;
} else {
rs485conf->flags &= ~SER_RS485_RTS_ON_SEND;
rs485conf->flags |= SER_RS485_RTS_AFTER_SEND;
}
/* check for tx enable gpio */
gflags = rs485conf->flags & SER_RS485_RTS_AFTER_SEND ?
GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
up->rts_gpiod = devm_gpiod_get_optional(dev, "rts", gflags);
if (IS_ERR(up->rts_gpiod)) {
ret = PTR_ERR(up->rts_gpiod);
if (ret == -EPROBE_DEFER)
return ret;
/*
* FIXME: the code historically ignored any other error than
* -EPROBE_DEFER and just went on without GPIO.
*/
up->rts_gpiod = NULL;
} else {
gpiod_set_consumer_name(up->rts_gpiod, "omap-serial");
}
return 0;
}
static int serial_omap_probe(struct platform_device *pdev)
{
struct omap_uart_port_info *omap_up_info = dev_get_platdata(&pdev->dev);
struct uart_omap_port *up;
struct resource *mem;
void __iomem *base;
int uartirq = 0;
int wakeirq = 0;
int ret;
/* The optional wakeirq may be specified in the board dts file */
if (pdev->dev.of_node) {
uartirq = irq_of_parse_and_map(pdev->dev.of_node, 0);
if (!uartirq)
return -EPROBE_DEFER;
wakeirq = irq_of_parse_and_map(pdev->dev.of_node, 1);
omap_up_info = of_get_uart_port_info(&pdev->dev);
pdev->dev.platform_data = omap_up_info;
} else {
uartirq = platform_get_irq(pdev, 0);
if (uartirq < 0)
return -EPROBE_DEFER;
}
up = devm_kzalloc(&pdev->dev, sizeof(*up), GFP_KERNEL);
if (!up)
return -ENOMEM;
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
base = devm_ioremap_resource(&pdev->dev, mem);
if (IS_ERR(base))
return PTR_ERR(base);
up->dev = &pdev->dev;
up->port.dev = &pdev->dev;
up->port.type = PORT_OMAP;
up->port.iotype = UPIO_MEM;
up->port.irq = uartirq;
up->port.regshift = 2;
up->port.fifosize = 64;
up->port.ops = &serial_omap_pops;
up->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_OMAP_CONSOLE);
if (pdev->dev.of_node)
ret = of_alias_get_id(pdev->dev.of_node, "serial");
else
ret = pdev->id;
if (ret < 0) {
dev_err(&pdev->dev, "failed to get alias/pdev id, errno %d\n",
ret);
goto err_port_line;
}
up->port.line = ret;
if (up->port.line >= OMAP_MAX_HSUART_PORTS) {
dev_err(&pdev->dev, "uart ID %d > MAX %d.\n", up->port.line,
OMAP_MAX_HSUART_PORTS);
ret = -ENXIO;
goto err_port_line;
}
up->wakeirq = wakeirq;
if (!up->wakeirq)
dev_info(up->port.dev, "no wakeirq for uart%d\n",
up->port.line);
ret = serial_omap_probe_rs485(up, &pdev->dev);
if (ret < 0)
goto err_rs485;
sprintf(up->name, "OMAP UART%d", up->port.line);
up->port.mapbase = mem->start;
up->port.membase = base;
up->port.flags = omap_up_info->flags;
up->port.uartclk = omap_up_info->uartclk;
up->port.rs485_config = serial_omap_config_rs485;
if (!up->port.uartclk) {
up->port.uartclk = DEFAULT_CLK_SPEED;
dev_warn(&pdev->dev,
"No clock speed specified: using default: %d\n",
DEFAULT_CLK_SPEED);
}
up->latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE;
up->calc_latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE;
cpu_latency_qos_add_request(&up->pm_qos_request, up->latency);
INIT_WORK(&up->qos_work, serial_omap_uart_qos_work);
platform_set_drvdata(pdev, up);
if (omap_up_info->autosuspend_timeout == 0)
omap_up_info->autosuspend_timeout = -1;
device_init_wakeup(up->dev, true);
pm_runtime_use_autosuspend(&pdev->dev);
pm_runtime_set_autosuspend_delay(&pdev->dev,
omap_up_info->autosuspend_timeout);
pm_runtime_irq_safe(&pdev->dev);
pm_runtime_enable(&pdev->dev);
pm_runtime_get_sync(&pdev->dev);
omap_serial_fill_features_erratas(up);
ui[up->port.line] = up;
serial_omap_add_console_port(up);
ret = uart_add_one_port(&serial_omap_reg, &up->port);
if (ret != 0)
goto err_add_port;
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);
return 0;
err_add_port:
pm_runtime_dont_use_autosuspend(&pdev->dev);
pm_runtime_put_sync(&pdev->dev);
pm_runtime_disable(&pdev->dev);
cpu_latency_qos_remove_request(&up->pm_qos_request);
device_init_wakeup(up->dev, false);
err_rs485:
err_port_line:
return ret;
}
static int serial_omap_remove(struct platform_device *dev)
{
struct uart_omap_port *up = platform_get_drvdata(dev);
pm_runtime_get_sync(up->dev);
uart_remove_one_port(&serial_omap_reg, &up->port);
pm_runtime_dont_use_autosuspend(up->dev);
pm_runtime_put_sync(up->dev);
pm_runtime_disable(up->dev);
cpu_latency_qos_remove_request(&up->pm_qos_request);
device_init_wakeup(&dev->dev, false);
return 0;
}
/*
* Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460)
* The access to uart register after MDR1 Access
* causes UART to corrupt data.
*
* Need a delay =
* 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS)
* give 10 times as much
*/
static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1)
{
u8 timeout = 255;
serial_out(up, UART_OMAP_MDR1, mdr1);
udelay(2);
serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_XMIT |
UART_FCR_CLEAR_RCVR);
/*
* Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and
* TX_FIFO_E bit is 1.
*/
while (UART_LSR_THRE != (serial_in(up, UART_LSR) &
(UART_LSR_THRE | UART_LSR_DR))) {
timeout--;
if (!timeout) {
/* Should *never* happen. we warn and carry on */
dev_crit(up->dev, "Errata i202: timedout %x\n",
serial_in(up, UART_LSR));
break;
}
udelay(1);
}
}
#ifdef CONFIG_PM
static void serial_omap_restore_context(struct uart_omap_port *up)
{
if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
serial_omap_mdr1_errataset(up, UART_OMAP_MDR1_DISABLE);
else
serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
serial_out(up, UART_EFR, UART_EFR_ECB);
serial_out(up, UART_LCR, 0x0); /* Operational mode */
serial_out(up, UART_IER, 0x0);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
serial_out(up, UART_DLL, up->dll);
serial_out(up, UART_DLM, up->dlh);
serial_out(up, UART_LCR, 0x0); /* Operational mode */
serial_out(up, UART_IER, up->ier);
serial_out(up, UART_FCR, up->fcr);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
serial_out(up, UART_MCR, up->mcr);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
serial_out(up, UART_OMAP_SCR, up->scr);
serial_out(up, UART_EFR, up->efr);
serial_out(up, UART_LCR, up->lcr);
if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
serial_omap_mdr1_errataset(up, up->mdr1);
else
serial_out(up, UART_OMAP_MDR1, up->mdr1);
serial_out(up, UART_OMAP_WER, up->wer);
}
static int serial_omap_runtime_suspend(struct device *dev)
{
struct uart_omap_port *up = dev_get_drvdata(dev);
if (!up)
return -EINVAL;
/*
* When using 'no_console_suspend', the console UART must not be
* suspended. Since driver suspend is managed by runtime suspend,
* preventing runtime suspend (by returning error) will keep device
* active during suspend.
*/
if (up->is_suspending && !console_suspend_enabled &&
uart_console(&up->port))
return -EBUSY;
up->context_loss_cnt = serial_omap_get_context_loss_count(up);
serial_omap_enable_wakeup(up, true);
up->latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE;
schedule_work(&up->qos_work);
return 0;
}
static int serial_omap_runtime_resume(struct device *dev)
{
struct uart_omap_port *up = dev_get_drvdata(dev);
int loss_cnt = serial_omap_get_context_loss_count(up);
serial_omap_enable_wakeup(up, false);
if (loss_cnt < 0) {
dev_dbg(dev, "serial_omap_get_context_loss_count failed : %d\n",
loss_cnt);
serial_omap_restore_context(up);
} else if (up->context_loss_cnt != loss_cnt) {
serial_omap_restore_context(up);
}
up->latency = up->calc_latency;
schedule_work(&up->qos_work);
return 0;
}
#endif
static const struct dev_pm_ops serial_omap_dev_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(serial_omap_suspend, serial_omap_resume)
SET_RUNTIME_PM_OPS(serial_omap_runtime_suspend,
serial_omap_runtime_resume, NULL)
.prepare = serial_omap_prepare,
.complete = serial_omap_complete,
};
#if defined(CONFIG_OF)
static const struct of_device_id omap_serial_of_match[] = {
{ .compatible = "ti,omap2-uart" },
{ .compatible = "ti,omap3-uart" },
{ .compatible = "ti,omap4-uart" },
{},
};
MODULE_DEVICE_TABLE(of, omap_serial_of_match);
#endif
static struct platform_driver serial_omap_driver = {
.probe = serial_omap_probe,
.remove = serial_omap_remove,
.driver = {
.name = OMAP_SERIAL_DRIVER_NAME,
.pm = &serial_omap_dev_pm_ops,
.of_match_table = of_match_ptr(omap_serial_of_match),
},
};
static int __init serial_omap_init(void)
{
int ret;
ret = uart_register_driver(&serial_omap_reg);
if (ret != 0)
return ret;
ret = platform_driver_register(&serial_omap_driver);
if (ret != 0)
uart_unregister_driver(&serial_omap_reg);
return ret;
}
static void __exit serial_omap_exit(void)
{
platform_driver_unregister(&serial_omap_driver);
uart_unregister_driver(&serial_omap_reg);
}
module_init(serial_omap_init);
module_exit(serial_omap_exit);
MODULE_DESCRIPTION("OMAP High Speed UART driver");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Texas Instruments Inc");
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