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linux_dsm_epyc7002/drivers/tty/serial/omap-serial.c
Paul Walmsley be4b028195 tty: serial: OMAP: block idle while the UART is transferring data in PIO mode 
Prevent OMAP UARTs from going idle while they are still transferring
data in PIO mode.  This works around an oversight in the OMAP UART
hardware present in OMAP34xx and earlier: an idle UART won't send a
wakeup when the TX FIFO threshold is reached.  This causes long delays
during data transmission when the MPU powerdomain enters a low-power
mode.  The MPU interrupt controller is not able to respond to
interrupts when it's in a low-power state, so the TX buffer is not
refilled until another wakeup event occurs.

This fix changes the erratum i291 DMA idle workaround.  Rather than
toggling between force-idle and no-idle, it will toggle between
smart-idle and no-idle.  The important part of the workaround is the
no-idle part, so this shouldn't result in any change in behavior.

This fix should work on all OMAP UARTs.  Future patches intended for
the 3.4 merge window will make this workaround conditional on a
"feature" flag, and will use the OMAP36xx+ TX event wakeup support.

Thanks to Kevin Hilman <khilman@ti.com> for mentioning the erratum i291
workaround, which led to the development of this approach.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: Govindraj.R <govindraj.raja@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-02-09 10:48:34 -08:00

1689 lines
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/*
* 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>
*
* 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.
*
* 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.
*/
#if defined(CONFIG_SERIAL_OMAP_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif
#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/io.h>
#include <linux/dma-mapping.h>
#include <linux/clk.h>
#include <linux/serial_core.h>
#include <linux/irq.h>
#include <linux/pm_runtime.h>
#include <linux/of.h>
#include <plat/dma.h>
#include <plat/dmtimer.h>
#include <plat/omap-serial.h>
#define DEFAULT_CLK_SPEED 48000000 /* 48Mhz*/
/* SCR register bitmasks */
#define OMAP_UART_SCR_RX_TRIG_GRANU1_MASK (1 << 7)
/* FCR register bitmasks */
#define OMAP_UART_FCR_RX_FIFO_TRIG_SHIFT 6
#define OMAP_UART_FCR_RX_FIFO_TRIG_MASK (0x3 << 6)
static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
/* Forward declaration of functions */
static void uart_tx_dma_callback(int lch, u16 ch_status, void *data);
static void serial_omap_rxdma_poll(unsigned long uart_no);
static int serial_omap_start_rxdma(struct uart_omap_port *up);
static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1);
static struct workqueue_struct *serial_omap_uart_wq;
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);
}
/*
* serial_omap_get_divisor - calculate divisor value
* @port: uart port info
* @baud: baudrate for which divisor needs to be calculated.
*
* We have written our own function to get the divisor so as to support
* 13x mode. 3Mbps Baudrate as an different divisor.
* Reference OMAP TRM Chapter 17:
* Table 17-1. UART Mode Baud Rates, Divisor Values, and Error Rates
* referring to oversampling - divisor value
* baudrate 460,800 to 3,686,400 all have divisor 13
* except 3,000,000 which has divisor value 16
*/
static unsigned int
serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
{
unsigned int divisor;
if (baud > OMAP_MODE13X_SPEED && baud != 3000000)
divisor = 13;
else
divisor = 16;
return port->uartclk/(baud * divisor);
}
static void serial_omap_stop_rxdma(struct uart_omap_port *up)
{
if (up->uart_dma.rx_dma_used) {
del_timer(&up->uart_dma.rx_timer);
omap_stop_dma(up->uart_dma.rx_dma_channel);
omap_free_dma(up->uart_dma.rx_dma_channel);
up->uart_dma.rx_dma_channel = OMAP_UART_DMA_CH_FREE;
up->uart_dma.rx_dma_used = false;
pm_runtime_mark_last_busy(&up->pdev->dev);
pm_runtime_put_autosuspend(&up->pdev->dev);
}
}
static void serial_omap_enable_ms(struct uart_port *port)
{
struct uart_omap_port *up = (struct uart_omap_port *)port;
dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->port.line);
pm_runtime_get_sync(&up->pdev->dev);
up->ier |= UART_IER_MSI;
serial_out(up, UART_IER, up->ier);
pm_runtime_put(&up->pdev->dev);
}
static void serial_omap_stop_tx(struct uart_port *port)
{
struct uart_omap_port *up = (struct uart_omap_port *)port;
struct omap_uart_port_info *pdata = up->pdev->dev.platform_data;
if (up->use_dma &&
up->uart_dma.tx_dma_channel != OMAP_UART_DMA_CH_FREE) {
/*
* Check if dma is still active. If yes do nothing,
* return. Else stop dma
*/
if (omap_get_dma_active_status(up->uart_dma.tx_dma_channel))
return;
omap_stop_dma(up->uart_dma.tx_dma_channel);
omap_free_dma(up->uart_dma.tx_dma_channel);
up->uart_dma.tx_dma_channel = OMAP_UART_DMA_CH_FREE;
pm_runtime_mark_last_busy(&up->pdev->dev);
pm_runtime_put_autosuspend(&up->pdev->dev);
}
pm_runtime_get_sync(&up->pdev->dev);
if (up->ier & UART_IER_THRI) {
up->ier &= ~UART_IER_THRI;
serial_out(up, UART_IER, up->ier);
}
if (!up->use_dma && pdata->set_forceidle)
pdata->set_forceidle(up->pdev);
pm_runtime_mark_last_busy(&up->pdev->dev);
pm_runtime_put_autosuspend(&up->pdev->dev);
}
static void serial_omap_stop_rx(struct uart_port *port)
{
struct uart_omap_port *up = (struct uart_omap_port *)port;
pm_runtime_get_sync(&up->pdev->dev);
if (up->use_dma)
serial_omap_stop_rxdma(up);
up->ier &= ~UART_IER_RLSI;
up->port.read_status_mask &= ~UART_LSR_DR;
serial_out(up, UART_IER, up->ier);
pm_runtime_mark_last_busy(&up->pdev->dev);
pm_runtime_put_autosuspend(&up->pdev->dev);
}
static inline void receive_chars(struct uart_omap_port *up,
unsigned int *status)
{
struct tty_struct *tty = up->port.state->port.tty;
unsigned int flag, lsr = *status;
unsigned char ch = 0;
int max_count = 256;
do {
if (likely(lsr & UART_LSR_DR))
ch = serial_in(up, UART_RX);
flag = TTY_NORMAL;
up->port.icount.rx++;
if (unlikely(lsr & UART_LSR_BRK_ERROR_BITS)) {
/*
* For statistics only
*/
if (lsr & UART_LSR_BI) {
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))
goto ignore_char;
} else if (lsr & UART_LSR_PE) {
up->port.icount.parity++;
} else if (lsr & UART_LSR_FE) {
up->port.icount.frame++;
}
if (lsr & UART_LSR_OE)
up->port.icount.overrun++;
/*
* Mask off conditions which should be ignored.
*/
lsr &= up->port.read_status_mask;
#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
if (lsr & UART_LSR_BI)
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(&up->port, ch))
goto ignore_char;
uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag);
ignore_char:
lsr = serial_in(up, UART_LSR);
} while ((lsr & (UART_LSR_DR | UART_LSR_BI)) && (max_count-- > 0));
spin_unlock(&up->port.lock);
tty_flip_buffer_push(tty);
spin_lock(&up->port.lock);
}
static void transmit_chars(struct uart_omap_port *up)
{
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 = (struct uart_omap_port *)port;
struct omap_uart_port_info *pdata = up->pdev->dev.platform_data;
struct circ_buf *xmit;
unsigned int start;
int ret = 0;
if (!up->use_dma) {
pm_runtime_get_sync(&up->pdev->dev);
serial_omap_enable_ier_thri(up);
if (pdata->set_noidle)
pdata->set_noidle(up->pdev);
pm_runtime_mark_last_busy(&up->pdev->dev);
pm_runtime_put_autosuspend(&up->pdev->dev);
return;
}
if (up->uart_dma.tx_dma_used)
return;
xmit = &up->port.state->xmit;
if (up->uart_dma.tx_dma_channel == OMAP_UART_DMA_CH_FREE) {
pm_runtime_get_sync(&up->pdev->dev);
ret = omap_request_dma(up->uart_dma.uart_dma_tx,
"UART Tx DMA",
(void *)uart_tx_dma_callback, up,
&(up->uart_dma.tx_dma_channel));
if (ret < 0) {
serial_omap_enable_ier_thri(up);
return;
}
}
spin_lock(&(up->uart_dma.tx_lock));
up->uart_dma.tx_dma_used = true;
spin_unlock(&(up->uart_dma.tx_lock));
start = up->uart_dma.tx_buf_dma_phys +
(xmit->tail & (UART_XMIT_SIZE - 1));
up->uart_dma.tx_buf_size = uart_circ_chars_pending(xmit);
/*
* It is a circular buffer. See if the buffer has wounded back.
* If yes it will have to be transferred in two separate dma
* transfers
*/
if (start + up->uart_dma.tx_buf_size >=
up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE)
up->uart_dma.tx_buf_size =
(up->uart_dma.tx_buf_dma_phys +
UART_XMIT_SIZE) - start;
omap_set_dma_dest_params(up->uart_dma.tx_dma_channel, 0,
OMAP_DMA_AMODE_CONSTANT,
up->uart_dma.uart_base, 0, 0);
omap_set_dma_src_params(up->uart_dma.tx_dma_channel, 0,
OMAP_DMA_AMODE_POST_INC, start, 0, 0);
omap_set_dma_transfer_params(up->uart_dma.tx_dma_channel,
OMAP_DMA_DATA_TYPE_S8,
up->uart_dma.tx_buf_size, 1,
OMAP_DMA_SYNC_ELEMENT,
up->uart_dma.uart_dma_tx, 0);
/* FIXME: Cache maintenance needed here? */
omap_start_dma(up->uart_dma.tx_dma_channel);
}
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;
}
/**
* serial_omap_irq() - This handles the interrupt from one port
* @irq: uart port irq number
* @dev_id: uart port info
*/
static inline irqreturn_t serial_omap_irq(int irq, void *dev_id)
{
struct uart_omap_port *up = dev_id;
unsigned int iir, lsr;
unsigned long flags;
pm_runtime_get_sync(&up->pdev->dev);
iir = serial_in(up, UART_IIR);
if (iir & UART_IIR_NO_INT) {
pm_runtime_mark_last_busy(&up->pdev->dev);
pm_runtime_put_autosuspend(&up->pdev->dev);
return IRQ_NONE;
}
spin_lock_irqsave(&up->port.lock, flags);
lsr = serial_in(up, UART_LSR);
if (iir & UART_IIR_RLSI) {
if (!up->use_dma) {
if (lsr & UART_LSR_DR)
receive_chars(up, &lsr);
} else {
up->ier &= ~(UART_IER_RDI | UART_IER_RLSI);
serial_out(up, UART_IER, up->ier);
if ((serial_omap_start_rxdma(up) != 0) &&
(lsr & UART_LSR_DR))
receive_chars(up, &lsr);
}
}
check_modem_status(up);
if ((lsr & UART_LSR_THRE) && (iir & UART_IIR_THRI))
transmit_chars(up);
spin_unlock_irqrestore(&up->port.lock, flags);
pm_runtime_mark_last_busy(&up->pdev->dev);
pm_runtime_put_autosuspend(&up->pdev->dev);
up->port_activity = jiffies;
return IRQ_HANDLED;
}
static unsigned int serial_omap_tx_empty(struct uart_port *port)
{
struct uart_omap_port *up = (struct uart_omap_port *)port;
unsigned long flags = 0;
unsigned int ret = 0;
pm_runtime_get_sync(&up->pdev->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_put(&up->pdev->dev);
return ret;
}
static unsigned int serial_omap_get_mctrl(struct uart_port *port)
{
struct uart_omap_port *up = (struct uart_omap_port *)port;
unsigned int status;
unsigned int ret = 0;
pm_runtime_get_sync(&up->pdev->dev);
status = check_modem_status(up);
pm_runtime_put(&up->pdev->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 = (struct uart_omap_port *)port;
unsigned char mcr = 0;
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->pdev->dev);
up->mcr = serial_in(up, UART_MCR);
up->mcr |= mcr;
serial_out(up, UART_MCR, up->mcr);
pm_runtime_put(&up->pdev->dev);
}
static void serial_omap_break_ctl(struct uart_port *port, int break_state)
{
struct uart_omap_port *up = (struct 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->pdev->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_put(&up->pdev->dev);
}
static int serial_omap_startup(struct uart_port *port)
{
struct uart_omap_port *up = (struct 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;
dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->port.line);
pm_runtime_get_sync(&up->pdev->dev);
/*
* Clear the FIFO buffers and disable them.
* (they will be reenabled in set_termios())
*/
serial_omap_clear_fifos(up);
/* For Hardware flow control */
serial_out(up, UART_MCR, UART_MCR_RTS);
/*
* 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;
if (up->use_dma) {
free_page((unsigned long)up->port.state->xmit.buf);
up->port.state->xmit.buf = dma_alloc_coherent(NULL,
UART_XMIT_SIZE,
(dma_addr_t *)&(up->uart_dma.tx_buf_dma_phys),
0);
init_timer(&(up->uart_dma.rx_timer));
up->uart_dma.rx_timer.function = serial_omap_rxdma_poll;
up->uart_dma.rx_timer.data = up->port.line;
/* Currently the buffer size is 4KB. Can increase it */
up->uart_dma.rx_buf = dma_alloc_coherent(NULL,
up->uart_dma.rx_buf_size,
(dma_addr_t *)&(up->uart_dma.rx_buf_dma_phys), 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 */
serial_out(up, UART_OMAP_WER, OMAP_UART_WER_MOD_WKUP);
pm_runtime_mark_last_busy(&up->pdev->dev);
pm_runtime_put_autosuspend(&up->pdev->dev);
up->port_activity = jiffies;
return 0;
}
static void serial_omap_shutdown(struct uart_port *port)
{
struct uart_omap_port *up = (struct 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->pdev->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);
if (up->use_dma) {
dma_free_coherent(up->port.dev,
UART_XMIT_SIZE, up->port.state->xmit.buf,
up->uart_dma.tx_buf_dma_phys);
up->port.state->xmit.buf = NULL;
serial_omap_stop_rx(port);
dma_free_coherent(up->port.dev,
up->uart_dma.rx_buf_size, up->uart_dma.rx_buf,
up->uart_dma.rx_buf_dma_phys);
up->uart_dma.rx_buf = NULL;
}
pm_runtime_put(&up->pdev->dev);
free_irq(up->port.irq, up);
}
static inline void
serial_omap_configure_xonxoff
(struct uart_omap_port *up, struct ktermios *termios)
{
up->lcr = serial_in(up, UART_LCR);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
up->efr = serial_in(up, UART_EFR);
serial_out(up, UART_EFR, up->efr & ~UART_EFR_ECB);
serial_out(up, UART_XON1, termios->c_cc[VSTART]);
serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
/* clear SW control mode bits */
up->efr &= OMAP_UART_SW_CLR;
/*
* IXON Flag:
* Enable XON/XOFF flow control on output.
* Transmit XON1, XOFF1
*/
if (termios->c_iflag & IXON)
up->efr |= OMAP_UART_SW_TX;
/*
* IXOFF Flag:
* Enable XON/XOFF flow control on input.
* Receiver compares XON1, XOFF1.
*/
if (termios->c_iflag & IXOFF)
up->efr |= OMAP_UART_SW_RX;
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);
/*
* 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;
serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
/* Enable special char function UARTi.EFR_REG[5] and
* load the new software flow control mode IXON or IXOFF
* and restore the UARTi.EFR_REG[4] ENHANCED_EN value.
*/
serial_out(up, UART_EFR, up->efr | UART_EFR_SCD);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
serial_out(up, UART_MCR, up->mcr & ~UART_MCR_TCRTLR);
serial_out(up, UART_LCR, up->lcr);
}
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);
pm_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 = (struct uart_omap_port *)port;
unsigned char cval = 0;
unsigned char efr = 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;
/*
* 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 = (1000000 * up->port.fifosize) /
(1000 * 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;
if (up->use_dma)
up->fcr |= UART_FCR_DMA_SELECT;
/*
* Ok, we're now changing the port state. Do it with
* interrupts disabled.
*/
pm_runtime_get_sync(&up->pdev->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 = OMAP_UART_SCR_TX_EMPTY;
/* 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);
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);
serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
/* FIFO ENABLE, DMA MODE */
up->scr |= OMAP_UART_SCR_RX_TRIG_GRANU1_MASK;
if (up->use_dma) {
serial_out(up, UART_TI752_TLR, 0);
up->scr |= UART_FCR_TRIGGER_4;
} else {
/* Set receive FIFO threshold to 1 byte */
up->fcr &= ~OMAP_UART_FCR_RX_FIFO_TRIG_MASK;
up->fcr |= (0x1 << OMAP_UART_FCR_RX_FIFO_TRIG_SHIFT);
}
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);
serial_out(up, UART_EFR, up->efr);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
serial_out(up, UART_MCR, up->mcr);
/* 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);
up->efr = serial_in(up, UART_EFR);
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 (baud > 230400 && baud != 3000000)
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);
/* Hardware Flow Control Configuration */
if (termios->c_cflag & CRTSCTS) {
efr |= (UART_EFR_CTS | UART_EFR_RTS);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
up->mcr = serial_in(up, UART_MCR);
serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
up->efr = serial_in(up, UART_EFR);
serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
serial_out(up, UART_EFR, efr); /* Enable AUTORTS and AUTOCTS */
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
serial_out(up, UART_MCR, up->mcr | UART_MCR_RTS);
serial_out(up, UART_LCR, cval);
}
serial_omap_set_mctrl(&up->port, up->port.mctrl);
/* Software Flow Control Configuration */
serial_omap_configure_xonxoff(up, termios);
spin_unlock_irqrestore(&up->port.lock, flags);
pm_runtime_put(&up->pdev->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 = (struct 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->pdev->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);
if (!device_may_wakeup(&up->pdev->dev)) {
if (!state)
pm_runtime_forbid(&up->pdev->dev);
else
pm_runtime_allow(&up->pdev->dev);
}
pm_runtime_put(&up->pdev->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 = (struct uart_omap_port *)port;
dev_dbg(up->port.dev, "serial_omap_config_port+%d\n",
up->port.line);
up->port.type = PORT_OMAP;
}
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 = (struct 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 inline void 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 = (struct uart_omap_port *)port;
pm_runtime_get_sync(&up->pdev->dev);
wait_for_xmitr(up);
serial_out(up, UART_TX, ch);
pm_runtime_put(&up->pdev->dev);
}
static int serial_omap_poll_get_char(struct uart_port *port)
{
struct uart_omap_port *up = (struct uart_omap_port *)port;
unsigned int status;
pm_runtime_get_sync(&up->pdev->dev);
status = serial_in(up, UART_LSR);
if (!(status & UART_LSR_DR))
return NO_POLL_CHAR;
status = serial_in(up, UART_RX);
pm_runtime_put(&up->pdev->dev);
return status;
}
#endif /* CONFIG_CONSOLE_POLL */
#ifdef CONFIG_SERIAL_OMAP_CONSOLE
static struct uart_omap_port *serial_omap_console_ports[4];
static struct uart_driver serial_omap_reg;
static void serial_omap_console_putchar(struct uart_port *port, int ch)
{
struct uart_omap_port *up = (struct 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->pdev->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->pdev->dev);
pm_runtime_put_autosuspend(&up->pdev->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
static 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,
.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_suspend(struct device *dev)
{
struct uart_omap_port *up = dev_get_drvdata(dev);
if (up) {
uart_suspend_port(&serial_omap_reg, &up->port);
flush_work_sync(&up->qos_work);
}
return 0;
}
static int serial_omap_resume(struct device *dev)
{
struct uart_omap_port *up = dev_get_drvdata(dev);
if (up)
uart_resume_port(&serial_omap_reg, &up->port);
return 0;
}
#endif
static void serial_omap_rxdma_poll(unsigned long uart_no)
{
struct uart_omap_port *up = ui[uart_no];
unsigned int curr_dma_pos, curr_transmitted_size;
int ret = 0;
curr_dma_pos = omap_get_dma_dst_pos(up->uart_dma.rx_dma_channel);
if ((curr_dma_pos == up->uart_dma.prev_rx_dma_pos) ||
(curr_dma_pos == 0)) {
if (jiffies_to_msecs(jiffies - up->port_activity) <
up->uart_dma.rx_timeout) {
mod_timer(&up->uart_dma.rx_timer, jiffies +
usecs_to_jiffies(up->uart_dma.rx_poll_rate));
} else {
serial_omap_stop_rxdma(up);
up->ier |= (UART_IER_RDI | UART_IER_RLSI);
serial_out(up, UART_IER, up->ier);
}
return;
}
curr_transmitted_size = curr_dma_pos -
up->uart_dma.prev_rx_dma_pos;
up->port.icount.rx += curr_transmitted_size;
tty_insert_flip_string(up->port.state->port.tty,
up->uart_dma.rx_buf +
(up->uart_dma.prev_rx_dma_pos -
up->uart_dma.rx_buf_dma_phys),
curr_transmitted_size);
tty_flip_buffer_push(up->port.state->port.tty);
up->uart_dma.prev_rx_dma_pos = curr_dma_pos;
if (up->uart_dma.rx_buf_size +
up->uart_dma.rx_buf_dma_phys == curr_dma_pos) {
ret = serial_omap_start_rxdma(up);
if (ret < 0) {
serial_omap_stop_rxdma(up);
up->ier |= (UART_IER_RDI | UART_IER_RLSI);
serial_out(up, UART_IER, up->ier);
}
} else {
mod_timer(&up->uart_dma.rx_timer, jiffies +
usecs_to_jiffies(up->uart_dma.rx_poll_rate));
}
up->port_activity = jiffies;
}
static void uart_rx_dma_callback(int lch, u16 ch_status, void *data)
{
return;
}
static int serial_omap_start_rxdma(struct uart_omap_port *up)
{
int ret = 0;
if (up->uart_dma.rx_dma_channel == -1) {
pm_runtime_get_sync(&up->pdev->dev);
ret = omap_request_dma(up->uart_dma.uart_dma_rx,
"UART Rx DMA",
(void *)uart_rx_dma_callback, up,
&(up->uart_dma.rx_dma_channel));
if (ret < 0)
return ret;
omap_set_dma_src_params(up->uart_dma.rx_dma_channel, 0,
OMAP_DMA_AMODE_CONSTANT,
up->uart_dma.uart_base, 0, 0);
omap_set_dma_dest_params(up->uart_dma.rx_dma_channel, 0,
OMAP_DMA_AMODE_POST_INC,
up->uart_dma.rx_buf_dma_phys, 0, 0);
omap_set_dma_transfer_params(up->uart_dma.rx_dma_channel,
OMAP_DMA_DATA_TYPE_S8,
up->uart_dma.rx_buf_size, 1,
OMAP_DMA_SYNC_ELEMENT,
up->uart_dma.uart_dma_rx, 0);
}
up->uart_dma.prev_rx_dma_pos = up->uart_dma.rx_buf_dma_phys;
/* FIXME: Cache maintenance needed here? */
omap_start_dma(up->uart_dma.rx_dma_channel);
mod_timer(&up->uart_dma.rx_timer, jiffies +
usecs_to_jiffies(up->uart_dma.rx_poll_rate));
up->uart_dma.rx_dma_used = true;
return ret;
}
static void serial_omap_continue_tx(struct uart_omap_port *up)
{
struct circ_buf *xmit = &up->port.state->xmit;
unsigned int start = up->uart_dma.tx_buf_dma_phys
+ (xmit->tail & (UART_XMIT_SIZE - 1));
if (uart_circ_empty(xmit))
return;
up->uart_dma.tx_buf_size = uart_circ_chars_pending(xmit);
/*
* It is a circular buffer. See if the buffer has wounded back.
* If yes it will have to be transferred in two separate dma
* transfers
*/
if (start + up->uart_dma.tx_buf_size >=
up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE)
up->uart_dma.tx_buf_size =
(up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE) - start;
omap_set_dma_dest_params(up->uart_dma.tx_dma_channel, 0,
OMAP_DMA_AMODE_CONSTANT,
up->uart_dma.uart_base, 0, 0);
omap_set_dma_src_params(up->uart_dma.tx_dma_channel, 0,
OMAP_DMA_AMODE_POST_INC, start, 0, 0);
omap_set_dma_transfer_params(up->uart_dma.tx_dma_channel,
OMAP_DMA_DATA_TYPE_S8,
up->uart_dma.tx_buf_size, 1,
OMAP_DMA_SYNC_ELEMENT,
up->uart_dma.uart_dma_tx, 0);
/* FIXME: Cache maintenance needed here? */
omap_start_dma(up->uart_dma.tx_dma_channel);
}
static void uart_tx_dma_callback(int lch, u16 ch_status, void *data)
{
struct uart_omap_port *up = (struct uart_omap_port *)data;
struct circ_buf *xmit = &up->port.state->xmit;
xmit->tail = (xmit->tail + up->uart_dma.tx_buf_size) & \
(UART_XMIT_SIZE - 1);
up->port.icount.tx += up->uart_dma.tx_buf_size;
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(&up->port);
if (uart_circ_empty(xmit)) {
spin_lock(&(up->uart_dma.tx_lock));
serial_omap_stop_tx(&up->port);
up->uart_dma.tx_dma_used = false;
spin_unlock(&(up->uart_dma.tx_lock));
} else {
omap_stop_dma(up->uart_dma.tx_dma_channel);
serial_omap_continue_tx(up);
}
up->port_activity = jiffies;
return;
}
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);
return omap_up_info;
}
static int serial_omap_probe(struct platform_device *pdev)
{
struct uart_omap_port *up;
struct resource *mem, *irq, *dma_tx, *dma_rx;
struct omap_uart_port_info *omap_up_info = pdev->dev.platform_data;
int ret = -ENOSPC;
if (pdev->dev.of_node)
omap_up_info = of_get_uart_port_info(&pdev->dev);
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!mem) {
dev_err(&pdev->dev, "no mem resource?\n");
return -ENODEV;
}
irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
if (!irq) {
dev_err(&pdev->dev, "no irq resource?\n");
return -ENODEV;
}
if (!request_mem_region(mem->start, resource_size(mem),
pdev->dev.driver->name)) {
dev_err(&pdev->dev, "memory region already claimed\n");
return -EBUSY;
}
dma_rx = platform_get_resource_byname(pdev, IORESOURCE_DMA, "rx");
if (!dma_rx) {
ret = -EINVAL;
goto err;
}
dma_tx = platform_get_resource_byname(pdev, IORESOURCE_DMA, "tx");
if (!dma_tx) {
ret = -EINVAL;
goto err;
}
up = kzalloc(sizeof(*up), GFP_KERNEL);
if (up == NULL) {
ret = -ENOMEM;
goto do_release_region;
}
up->pdev = pdev;
up->port.dev = &pdev->dev;
up->port.type = PORT_OMAP;
up->port.iotype = UPIO_MEM;
up->port.irq = irq->start;
up->port.regshift = 2;
up->port.fifosize = 64;
up->port.ops = &serial_omap_pops;
if (pdev->dev.of_node)
up->port.line = of_alias_get_id(pdev->dev.of_node, "serial");
else
up->port.line = pdev->id;
if (up->port.line < 0) {
dev_err(&pdev->dev, "failed to get alias/pdev id, errno %d\n",
up->port.line);
ret = -ENODEV;
goto err;
}
sprintf(up->name, "OMAP UART%d", up->port.line);
up->port.mapbase = mem->start;
up->port.membase = ioremap(mem->start, resource_size(mem));
if (!up->port.membase) {
dev_err(&pdev->dev, "can't ioremap UART\n");
ret = -ENOMEM;
goto err;
}
up->port.flags = omap_up_info->flags;
up->port.uartclk = omap_up_info->uartclk;
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->uart_dma.uart_base = mem->start;
up->errata = omap_up_info->errata;
if (omap_up_info->dma_enabled) {
up->uart_dma.uart_dma_tx = dma_tx->start;
up->uart_dma.uart_dma_rx = dma_rx->start;
up->use_dma = 1;
up->uart_dma.rx_buf_size = omap_up_info->dma_rx_buf_size;
up->uart_dma.rx_timeout = omap_up_info->dma_rx_timeout;
up->uart_dma.rx_poll_rate = omap_up_info->dma_rx_poll_rate;
spin_lock_init(&(up->uart_dma.tx_lock));
spin_lock_init(&(up->uart_dma.rx_lock));
up->uart_dma.tx_dma_channel = OMAP_UART_DMA_CH_FREE;
up->uart_dma.rx_dma_channel = OMAP_UART_DMA_CH_FREE;
}
up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
up->calc_latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
pm_qos_add_request(&up->pm_qos_request,
PM_QOS_CPU_DMA_LATENCY, up->latency);
serial_omap_uart_wq = create_singlethread_workqueue(up->name);
INIT_WORK(&up->qos_work, serial_omap_uart_qos_work);
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);
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 do_release_region;
pm_runtime_put(&pdev->dev);
platform_set_drvdata(pdev, up);
return 0;
err:
dev_err(&pdev->dev, "[UART%d]: failure [%s]: %d\n",
pdev->id, __func__, ret);
do_release_region:
release_mem_region(mem->start, resource_size(mem));
return ret;
}
static int serial_omap_remove(struct platform_device *dev)
{
struct uart_omap_port *up = platform_get_drvdata(dev);
if (up) {
pm_runtime_disable(&up->pdev->dev);
uart_remove_one_port(&serial_omap_reg, &up->port);
pm_qos_remove_request(&up->pm_qos_request);
kfree(up);
}
platform_set_drvdata(dev, NULL);
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->pdev->dev, "Errata i202: timedout %x\n",
serial_in(up, UART_LSR));
break;
}
udelay(1);
}
}
#ifdef CONFIG_PM_RUNTIME
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);
}
static int serial_omap_runtime_suspend(struct device *dev)
{
struct uart_omap_port *up = dev_get_drvdata(dev);
struct omap_uart_port_info *pdata = dev->platform_data;
if (!up)
return -EINVAL;
if (!pdata || !pdata->enable_wakeup)
return 0;
if (pdata->get_context_loss_count)
up->context_loss_cnt = pdata->get_context_loss_count(dev);
if (device_may_wakeup(dev)) {
if (!up->wakeups_enabled) {
pdata->enable_wakeup(up->pdev, true);
up->wakeups_enabled = true;
}
} else {
if (up->wakeups_enabled) {
pdata->enable_wakeup(up->pdev, false);
up->wakeups_enabled = false;
}
}
/* Errata i291 */
if (up->use_dma && pdata->set_forceidle &&
(up->errata & UART_ERRATA_i291_DMA_FORCEIDLE))
pdata->set_forceidle(up->pdev);
up->latency = PM_QOS_CPU_DMA_LAT_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);
struct omap_uart_port_info *pdata = dev->platform_data;
if (up) {
if (pdata->get_context_loss_count) {
u32 loss_cnt = pdata->get_context_loss_count(dev);
if (up->context_loss_cnt != loss_cnt)
serial_omap_restore_context(up);
}
/* Errata i291 */
if (up->use_dma && pdata->set_noidle &&
(up->errata & UART_ERRATA_i291_DMA_FORCEIDLE))
pdata->set_noidle(up->pdev);
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)
};
#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 = 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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