linux/drivers/tty/serial/omap-serial.c

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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/clk.h>
#include <linux/serial_core.h>
#include <linux/irq.h>
#include <linux/pm_runtime.h>
#include <linux/of.h>
#include <linux/gpio.h>
#include <plat/dmtimer.h>
#include <plat/omap-serial.h>
#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 DEFAULT_CLK_SPEED 48000000 /* 48Mhz*/
tty: serial: OMAP: use a 1-byte RX FIFO threshold in PIO mode In the (default) PIO mode, use a one-byte RX FIFO threshold. The OMAP UART IP blocks do not appear to be capable of waking the system under an RX timeout condition. Since the previous RX FIFO threshold was 16 bytes, this meant that omap-serial.c did not become aware of any received data until all those bytes arrived or until another UART interrupt occurred. This made the serial console and presumably other serial applications (GPS, serial Bluetooth) unusable or extremely slow. A 1-byte RX FIFO threshold also allows the MPU to enter a low-power consumption state while waiting for the FIFO to fill. This can be verified using the serial console by comparing the behavior when "0123456789abcde" is pasted in from another window, with the behavior when "0123456789abcdef" is pasted in. Since the former string is less than sixteen bytes long, the string is not echoed for some time, while the latter string is echoed immediately. DMA operation is unaffected by this patch. Thanks to Russell King - ARM Linux <linux@arm.linux.org.uk> for some additional information on the standard behavior of the RX timeout event, which was used to improve this commit description. Signed-off-by: Paul Walmsley <paul@pwsan.com> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: Govindraj Raja <govindraj.r@ti.com> Cc: Alan Cox <alan@linux.intel.com> Cc: Russell King <linux@arm.linux.org.uk> Reviewed-by: Kevin Hilman <khilman@ti.com> Tested-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-01-26 10:50:36 +08:00
/* 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)
/* 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
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);
2011-11-09 20:11:21 +08:00
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);
}
static int serial_omap_get_context_loss_count(struct uart_omap_port *up)
{
struct omap_uart_port_info *pdata = up->dev->platform_data;
if (!pdata->get_context_loss_count)
return 0;
return pdata->get_context_loss_count(up->dev);
}
static void serial_omap_set_forceidle(struct uart_omap_port *up)
{
struct omap_uart_port_info *pdata = up->dev->platform_data;
if (pdata->set_forceidle)
pdata->set_forceidle(up->dev);
}
static void serial_omap_set_noidle(struct uart_omap_port *up)
{
struct omap_uart_port_info *pdata = up->dev->platform_data;
if (pdata->set_noidle)
pdata->set_noidle(up->dev);
}
static void serial_omap_enable_wakeup(struct uart_omap_port *up, bool enable)
{
struct omap_uart_port_info *pdata = up->dev->platform_data;
if (pdata->enable_wakeup)
pdata->enable_wakeup(up->dev, enable);
}
/*
* 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_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_put(up->dev);
}
static void serial_omap_stop_tx(struct uart_port *port)
{
struct uart_omap_port *up = to_uart_omap_port(port);
pm_runtime_get_sync(up->dev);
if (up->ier & UART_IER_THRI) {
up->ier &= ~UART_IER_THRI;
serial_out(up, UART_IER, up->ier);
}
serial_omap_set_forceidle(up);
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>
2012-01-26 10:50:52 +08:00
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;
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)
{
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);
pm_runtime_get_sync(up->dev);
serial_omap_enable_ier_thri(up);
serial_omap_set_noidle(up);
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;
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 inline irqreturn_t serial_omap_irq(int irq, void *dev_id)
{
struct uart_omap_port *up = dev_id;
struct tty_struct *tty = up->port.state->port.tty;
unsigned int iir, lsr;
unsigned int type;
unsigned long flags;
irqreturn_t ret = IRQ_NONE;
int max_count = 256;
spin_lock_irqsave(&up->port.lock, flags);
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:
if (lsr & UART_LSR_THRE)
transmit_chars(up);
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 (!(iir & UART_IIR_NO_INT) && max_count--);
spin_unlock_irqrestore(&up->port.lock, flags);
tty_flip_buffer_push(tty);
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_put(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_put(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;
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);
up->mcr = serial_in(up, UART_MCR);
up->mcr |= mcr;
serial_out(up, UART_MCR, up->mcr);
pm_runtime_put(up->dev);
if (gpio_is_valid(up->DTR_gpio) &&
!!(mctrl & TIOCM_DTR) != up->DTR_active) {
up->DTR_active = !up->DTR_active;
if (gpio_cansleep(up->DTR_gpio))
schedule_work(&up->qos_work);
else
gpio_set_value(up->DTR_gpio,
up->DTR_active != up->DTR_inverted);
}
}
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_put(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;
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);
/* 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;
/*
* 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->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_put(up->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);
}
2011-11-09 20:11:21 +08:00
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);
if (gpio_is_valid(up->DTR_gpio))
gpio_set_value_cansleep(up->DTR_gpio,
up->DTR_active != up->DTR_inverted);
2011-11-09 20:11:21 +08:00
}
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 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);
2011-11-09 20:11:21 +08:00
/* calculate wakeup latency constraint */
up->calc_latency = (USEC_PER_SEC * up->port.fifosize) / (baud / 8);
2011-11-09 20:11:21 +08:00
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 = 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 */
tty: serial: OMAP: use a 1-byte RX FIFO threshold in PIO mode In the (default) PIO mode, use a one-byte RX FIFO threshold. The OMAP UART IP blocks do not appear to be capable of waking the system under an RX timeout condition. Since the previous RX FIFO threshold was 16 bytes, this meant that omap-serial.c did not become aware of any received data until all those bytes arrived or until another UART interrupt occurred. This made the serial console and presumably other serial applications (GPS, serial Bluetooth) unusable or extremely slow. A 1-byte RX FIFO threshold also allows the MPU to enter a low-power consumption state while waiting for the FIFO to fill. This can be verified using the serial console by comparing the behavior when "0123456789abcde" is pasted in from another window, with the behavior when "0123456789abcdef" is pasted in. Since the former string is less than sixteen bytes long, the string is not echoed for some time, while the latter string is echoed immediately. DMA operation is unaffected by this patch. Thanks to Russell King - ARM Linux <linux@arm.linux.org.uk> for some additional information on the standard behavior of the RX timeout event, which was used to improve this commit description. Signed-off-by: Paul Walmsley <paul@pwsan.com> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: Govindraj Raja <govindraj.r@ti.com> Cc: Alan Cox <alan@linux.intel.com> Cc: Russell King <linux@arm.linux.org.uk> Reviewed-by: Kevin Hilman <khilman@ti.com> Tested-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-01-26 10:50:36 +08:00
up->scr |= OMAP_UART_SCR_RX_TRIG_GRANU1_MASK;
/* 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);
tty: serial: OMAP: use a 1-byte RX FIFO threshold in PIO mode In the (default) PIO mode, use a one-byte RX FIFO threshold. The OMAP UART IP blocks do not appear to be capable of waking the system under an RX timeout condition. Since the previous RX FIFO threshold was 16 bytes, this meant that omap-serial.c did not become aware of any received data until all those bytes arrived or until another UART interrupt occurred. This made the serial console and presumably other serial applications (GPS, serial Bluetooth) unusable or extremely slow. A 1-byte RX FIFO threshold also allows the MPU to enter a low-power consumption state while waiting for the FIFO to fill. This can be verified using the serial console by comparing the behavior when "0123456789abcde" is pasted in from another window, with the behavior when "0123456789abcdef" is pasted in. Since the former string is less than sixteen bytes long, the string is not echoed for some time, while the latter string is echoed immediately. DMA operation is unaffected by this patch. Thanks to Russell King - ARM Linux <linux@arm.linux.org.uk> for some additional information on the standard behavior of the RX timeout event, which was used to improve this commit description. Signed-off-by: Paul Walmsley <paul@pwsan.com> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: Govindraj Raja <govindraj.r@ti.com> Cc: Alan Cox <alan@linux.intel.com> Cc: Russell King <linux@arm.linux.org.uk> Reviewed-by: Kevin Hilman <khilman@ti.com> Tested-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-01-26 10:50:36 +08:00
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->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);
if (!device_may_wakeup(up->dev)) {
if (!state)
pm_runtime_forbid(up->dev);
else
pm_runtime_allow(up->dev);
}
pm_runtime_put(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;
}
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 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 = to_uart_omap_port(port);
pm_runtime_get_sync(up->dev);
wait_for_xmitr(up);
serial_out(up, UART_TX, ch);
pm_runtime_put(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))
return NO_POLL_CHAR;
status = serial_in(up, UART_RX);
pm_runtime_put(up->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 = 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
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);
2011-11-09 20:11:21 +08:00
if (up) {
uart_suspend_port(&serial_omap_reg, &up->port);
2011-11-09 20:11:21 +08:00
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 omap_serial_fill_features_erratas(struct uart_omap_port *up)
{
u32 mvr, scheme;
u16 revision, major, minor;
mvr = serial_in(up, UART_OMAP_MVER);
/* 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);
break;
case OMAP_UART_REV_63:
up->errata |= UART_ERRATA_i202_MDR1_ACCESS;
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);
return omap_up_info;
}
static int serial_omap_probe(struct platform_device *pdev)
{
struct uart_omap_port *up;
struct resource *mem, *irq;
struct omap_uart_port_info *omap_up_info = pdev->dev.platform_data;
int ret;
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 (!devm_request_mem_region(&pdev->dev, mem->start, resource_size(mem),
pdev->dev.driver->name)) {
dev_err(&pdev->dev, "memory region already claimed\n");
return -EBUSY;
}
if (gpio_is_valid(omap_up_info->DTR_gpio) &&
omap_up_info->DTR_present) {
ret = gpio_request(omap_up_info->DTR_gpio, "omap-serial");
if (ret < 0)
return ret;
ret = gpio_direction_output(omap_up_info->DTR_gpio,
omap_up_info->DTR_inverted);
if (ret < 0)
return ret;
}
up = devm_kzalloc(&pdev->dev, sizeof(*up), GFP_KERNEL);
if (!up)
return -ENOMEM;
if (gpio_is_valid(omap_up_info->DTR_gpio) &&
omap_up_info->DTR_present) {
up->DTR_gpio = omap_up_info->DTR_gpio;
up->DTR_inverted = omap_up_info->DTR_inverted;
} else
up->DTR_gpio = -EINVAL;
up->DTR_active = 0;
up->dev = &pdev->dev;
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_port_line;
}
sprintf(up->name, "OMAP UART%d", up->port.line);
up->port.mapbase = mem->start;
up->port.membase = devm_ioremap(&pdev->dev, mem->start,
resource_size(mem));
if (!up->port.membase) {
dev_err(&pdev->dev, "can't ioremap UART\n");
ret = -ENOMEM;
goto err_ioremap;
}
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);
}
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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);
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_put(&pdev->dev);
platform_set_drvdata(pdev, up);
return 0;
err_add_port:
pm_runtime_put(&pdev->dev);
pm_runtime_disable(&pdev->dev);
err_ioremap:
err_port_line:
dev_err(&pdev->dev, "[UART%d]: failure [%s]: %d\n",
pdev->id, __func__, ret);
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->dev);
uart_remove_one_port(&serial_omap_reg, &up->port);
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pm_qos_remove_request(&up->pm_qos_request);
}
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->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)
return 0;
up->context_loss_cnt = serial_omap_get_context_loss_count(up);
if (device_may_wakeup(dev)) {
if (!up->wakeups_enabled) {
serial_omap_enable_wakeup(up, true);
up->wakeups_enabled = true;
}
} else {
if (up->wakeups_enabled) {
serial_omap_enable_wakeup(up, false);
up->wakeups_enabled = false;
}
}
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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 && pdata) {
u32 loss_cnt = serial_omap_get_context_loss_count(up);
if (up->context_loss_cnt != loss_cnt)
serial_omap_restore_context(up);
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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");