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linux/drivers/tty/serial/omap-serial.c
Nishanth Menon 7af0ea5dee tty: serial: omap: Increase max consoles and add check to prevent crash 
Increase the maximum number of consoles possible to 10 since DRA7 now
has the maximum number of consoles possible. without doing this, for
example, enabling DRA7 UART10 results in internal data structures and
console cannot match up and we endup with a crash as follows:

[    1.903503] omap_uart 48424000.serial: [UART-1]: failure [serial_omap_probe]: -22
[    1.911437] omap_uart: probe of 48424000.serial failed with error -22
[    1.920379] Unable to handle kernel NULL pointer dereference at virtual address 00000004
[    1.928894] pgd = c0004000
[    1.931732] [00000004] *pgd=00000000
[    1.935485] Internal error: Oops: 5 [#1] SMP ARM
[    1.940338] Modules linked in:
[    1.943542] CPU: 1 PID: 12 Comm: kworker/1:0 Tainted: G        W      3.18.0-rc1-00001-g8821bc4-dirty #6
[    1.953521] task: ed8a2d00 ti: ed8a4000 task.ti: ed8a4000
[    1.959197] PC is at process_one_work+0x38/0x4a4
[    1.964050] LR is at 0x0
[    1.966705] pc : [<c00548e0>]    lr : [<00000000>]    psr: 40000093
[    1.966705] sp : ed8a5ea8  ip : ed8a5ec8  fp : eeb9abc0
[    1.978759] r10: ed8a4000  r9 : 00000008  r8 : ed842458
[    1.984252] r7 : 00000000  r6 : eeb9abc0  r5 : ed842440  r4 : edbf26a8
[    1.991119] r3 : 00000000  r2 : 00000000  r1 : 00000000  r0 : 00000000
[    1.997985] Flags: nZcv  IRQs off  FIQs on  Mode SVC_32  ISA ARM  Segment kernel
[    2.005767] Control: 10c5387d  Table: 8000406a  DAC: 00000015
[    2.011810] Process kworker/1:0 (pid: 12, stack limit = 0xed8a4248)
[    2.018371] Stack: (0xed8a5ea8 to 0xed8a6000)
[    2.022949] 5ea0:                   00000001 00000000 60000093 c008346c 00000001 ed8a5ec8
[    2.031555] 5ec0: c0054de4 eeb9abc0 ed8a4000 ed842458 00000008 ed8a4000 eeb9abc0 ed842440
[    2.040161] 5ee0: eeb9abc0 eeb9abf0 ed8a4000 ed842458 00000008 ed8a4000 eeb9abc0 c0054ec4
[    2.048767] 5f00: ed8a4000 eeb9ac4c a0000053 00000000 ed845bc0 ed842440 c0054d80 00000000
[    2.057342] 5f20: 00000000 00000000 00000000 c005999c 00000001 00000000 c05eaa64 ed842440
[    2.065948] 5f40: 00000000 00000000 dead4ead ffffffff ffffffff c097c680 00000000 00000000
[    2.074554] 5f60: c078acd4 ed8a5f64 ed8a5f64 00000000 00000000 dead4ead ffffffff ffffffff
[    2.083160] 5f80: c097c680 00000000 00000000 c078acd4 ed8a5f90 ed8a5f90 600000d3 ed845bc0
[    2.091766] 5fa0: c00598d4 00000000 00000000 c000e668 00000000 00000000 00000000 00000000
[    2.100341] 5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[    2.108947] 5fe0: 00000000 00000000 00000000 00000000 00000013 00000000 90005148 11010482
[    2.117553] [<c00548e0>] (process_one_work) from [<c0054ec4>] (worker_thread+0x144/0x498)
[    2.126159] [<c0054ec4>] (worker_thread) from [<c005999c>] (kthread+0xc8/0xe4)
[    2.133758] [<c005999c>] (kthread) from [<c000e668>] (ret_from_fork+0x14/0x2c)
[    2.141357] Code: e1a04001 e1a05000 e893000f e31e0004 (e5978004)
[    2.147766] ---[ end trace 5798e2803311b69f ]---
<snip>

The final solution is to transition off to use 8250 driver and no
dependency on console structures and move away from omap-serial
driver, hence no major cleanups are done for this driver, so add a
simple check to prevent future crashes in a similar manner in case of
platform with additional ports.

Signed-off-by: Nishanth Menon <nm@ti.com>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-06 14:57:18 -08:00

1940 lines
49 KiB
C
Raw Blame History

/*
* 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/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/of.h>
#include <linux/of_irq.h>
#include <linux/gpio.h>
#include <linux/of_gpio.h>
#include <linux/platform_data/serial-omap.h>
#include <dt-bindings/gpio/gpio.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;
u8 wakeups_enabled;
u32 features;
struct serial_rs485 rs485;
int rts_gpio;
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);
}
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);
}
static inline void serial_omap_enable_wakeirq(struct uart_omap_port *up,
bool enable)
{
if (!up->wakeirq)
return;
if (enable)
enable_irq(up->wakeirq);
else
disable_irq_nosync(up->wakeirq);
}
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 (enable == up->wakeups_enabled)
return;
serial_omap_enable_wakeirq(up, enable);
up->wakeups_enabled = enable;
if (!pdata || !pdata->enable_wakeup)
return;
pdata->enable_wakeup(up->dev, enable);
}
/*
* 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 (up->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 = (up->rs485.flags & SER_RS485_RTS_AFTER_SEND) ? 1 : 0;
if (gpio_get_value(up->rts_gpio) != res) {
if (up->rs485.delay_rts_after_send > 0)
mdelay(up->rs485.delay_rts_after_send);
gpio_set_value(up->rts_gpio, 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 ((up->rs485.flags & SER_RS485_ENABLED) &&
!(up->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 (up->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 = (up->rs485.flags & SER_RS485_RTS_ON_SEND) ? 1 : 0;
if (gpio_get_value(up->rts_gpio) != res) {
gpio_set_value(up->rts_gpio, res);
if (up->rs485.delay_rts_before_send > 0)
mdelay(up->rs485.delay_rts_before_send);
}
}
if ((up->rs485.flags & SER_RS485_ENABLED) &&
!(up->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;
unsigned char ch = 0;
if (likely(lsr & UART_LSR_DR))
ch = 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 (!(iir & UART_IIR_NO_INT) && 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;
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);
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 = request_irq(up->wakeirq, serial_omap_irq,
up->port.irqflags, up->name, up);
if (retval) {
free_irq(up->port.irq, up);
return retval;
}
disable_irq(up->wakeirq);
}
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 */
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);
if (up->wakeirq)
free_irq(up->wakeirq, up);
}
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 = 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);
if (termios->c_cflag & CRTSCTS && up->port.flags & UPF_HARD_FLOW) {
/* Enable AUTORTS and AUTOCTS */
up->efr |= UART_EFR_CTS | UART_EFR_RTS;
/* Ensure MCR RTS is asserted */
up->mcr |= UART_MCR_RTS;
} 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->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);
if (!device_may_wakeup(up->dev)) {
if (!state)
pm_runtime_forbid(up->dev);
else
pm_runtime_allow(up->dev);
}
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 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_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
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 void
serial_omap_config_rs485(struct uart_port *port, struct serial_rs485 *rs485conf)
{
struct uart_omap_port *up = to_uart_omap_port(port);
unsigned long flags;
unsigned int mode;
int val;
pm_runtime_get_sync(up->dev);
spin_lock_irqsave(&up->port.lock, flags);
/* Disable interrupts from this port */
mode = up->ier;
up->ier = 0;
serial_out(up, UART_IER, 0);
/* store new config */
up->rs485 = *rs485conf;
/*
* Just as a precaution, only allow rs485
* to be enabled if the gpio pin is valid
*/
if (gpio_is_valid(up->rts_gpio)) {
/* enable / disable rts */
val = (up->rs485.flags & SER_RS485_ENABLED) ?
SER_RS485_RTS_AFTER_SEND : SER_RS485_RTS_ON_SEND;
val = (up->rs485.flags & val) ? 1 : 0;
gpio_set_value(up->rts_gpio, val);
} else
up->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 (!(up->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);
}
spin_unlock_irqrestore(&up->port.lock, flags);
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);
}
static int
serial_omap_ioctl(struct uart_port *port, unsigned int cmd, unsigned long arg)
{
struct serial_rs485 rs485conf;
switch (cmd) {
case TIOCSRS485:
if (copy_from_user(&rs485conf, (void __user *) arg,
sizeof(rs485conf)))
return -EFAULT;
serial_omap_config_rs485(port, &rs485conf);
break;
case TIOCGRS485:
if (copy_to_user((void __user *) arg,
&(to_uart_omap_port(port)->rs485),
sizeof(rs485conf)))
return -EFAULT;
break;
default:
return -ENOIOCTLCMD;
}
return 0;
}
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,
.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,
.ioctl = serial_omap_ioctl,
#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);
return omap_up_info;
}
static int serial_omap_probe_rs485(struct uart_omap_port *up,
struct device_node *np)
{
struct serial_rs485 *rs485conf = &up->rs485;
u32 rs485_delay[2];
enum of_gpio_flags flags;
int ret;
rs485conf->flags = 0;
up->rts_gpio = -EINVAL;
if (!np)
return 0;
if (of_property_read_bool(np, "rs485-rts-active-high"))
rs485conf->flags |= SER_RS485_RTS_ON_SEND;
else
rs485conf->flags |= SER_RS485_RTS_AFTER_SEND;
/* check for tx enable gpio */
up->rts_gpio = of_get_named_gpio_flags(np, "rts-gpio", 0, &flags);
if (gpio_is_valid(up->rts_gpio)) {
ret = devm_gpio_request(up->dev, up->rts_gpio, "omap-serial");
if (ret < 0)
return ret;
ret = gpio_direction_output(up->rts_gpio,
flags & SER_RS485_RTS_AFTER_SEND);
if (ret < 0)
return ret;
} else if (up->rts_gpio == -EPROBE_DEFER) {
return -EPROBE_DEFER;
} else {
up->rts_gpio = -EINVAL;
}
if (of_property_read_u32_array(np, "rs485-rts-delay",
rs485_delay, 2) == 0) {
rs485conf->delay_rts_before_send = rs485_delay[0];
rs485conf->delay_rts_after_send = rs485_delay[1];
}
if (of_property_read_bool(np, "rs485-rx-during-tx"))
rs485conf->flags |= SER_RS485_RX_DURING_TX;
if (of_property_read_bool(np, "linux,rs485-enabled-at-boot-time"))
rs485conf->flags |= SER_RS485_ENABLED;
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->wakeirq = wakeirq;
if (!up->wakeirq)
dev_info(up->port.dev, "no wakeirq for uart%d\n",
up->port.line);
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;
}
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;
}
ret = serial_omap_probe_rs485(up, pdev->dev.of_node);
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;
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_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);
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_put(&pdev->dev);
pm_runtime_disable(&pdev->dev);
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_put_sync(up->dev);
pm_runtime_disable(up->dev);
uart_remove_one_port(&serial_omap_reg, &up->port);
pm_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_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);
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_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);
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 = 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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