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192.168.1.100 / T108 / e958203796650e3959a43708d67534bf36f4c83b / . / marvell / linux / drivers / tty / serial / pxa.c
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// SPDX-License-Identifier: GPL-2.0+
/*
* Based on drivers/serial/8250.c by Russell King.
*
* Author: Nicolas Pitre
* Created: Feb 20, 2003
* Copyright: (C) 2003 Monta Vista Software, Inc.
*
* Note 1: This driver is made separate from the already too overloaded
* 8250.c because it needs some kirks of its own and that'll make it
* easier to add DMA support.
*
* Note 2: I'm too sick of device allocation policies for serial ports.
* If someone else wants to request an "official" allocation of major/minor
* for this driver please be my guest. And don't forget that new hardware
* to come from Intel might have more than 3 or 4 of those UARTs. Let's
* hope for a better port registration and dynamic device allocation scheme
* with the serial core maintainer satisfaction to appear soon.
*/
#if defined(CONFIG_SERIAL_PXA_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/console.h>
#include <linux/sysrq.h>
#include <linux/serial_reg.h>
#include <linux/circ_buf.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/platform_device.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/serial_core.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/dma-mapping.h>
#include <linux/dmaengine.h>
#include <linux/cputype.h>
#include <linux/pm_qos.h>
#include <linux/pm_wakeup.h>
#include <linux/timer.h>
#include <linux/edge_wakeup_mmp.h>
#define DMA_BLOCK UART_XMIT_SIZE
#define DMA_BURST_SIZE 16
#define DMA_FIFO_THRESHOLD 32
#define DMA_RX_BLOCK_SIZE DMA_BLOCK
#define PXA_UART_TX 0
#define PXA_UART_RX 1
#define PXA_NAME_LEN 8
#define PXA_MAX_BAUD 1000000
#define DMA_INT_MASK (DCSR_ENDINTR | DCSR_BUSERR | DCSR_STARTINTR)
#define RESET_DMA_CHANNEL (DCSR_NODESC | DMA_INT_MASK)
#define DMA_ALIGNMENT 16
/*
* DMA related data is stored in this struct,
* making it separated from non-DMA mode.
*/
struct uart_pxa_dma {
#define TX_DMA_RUNNING (1 << 0)
#define RX_DMA_RUNNING (1 << 1)
unsigned int dma_status;
struct dma_chan *txdma_chan;
struct dma_chan *rxdma_chan;
struct dma_async_tx_descriptor *rx_desc;
struct dma_async_tx_descriptor *tx_desc;
void *txdma_addr;
void *rxdma_addr;
dma_addr_t txdma_addr_phys;
dma_addr_t rxdma_addr_phys;
int tx_stop;
int rx_stop;
dma_cookie_t rx_cookie;
dma_cookie_t tx_cookie;
unsigned int drcmr_tx;
unsigned int drcmr_rx;
int tx_size; /* size of last transmit bytes */
struct tasklet_struct tklet;
#ifdef CONFIG_PM
/* We needn't save rx dma register because we
* just restart the dma totallly after resume
*/
void *tx_buf_save;
int tx_saved_len;
#endif
bool dma_init;
};
struct uart_pxa_port {
struct uart_port port;
unsigned int ier;
unsigned char lcr;
unsigned int mcr;
unsigned int lsr_break_flag;
struct clk *clk;
char name[PXA_NAME_LEN];
struct timer_list pxa_timer;
struct pm_qos_request qos_idle[2];
s32 lpm_qos;
int edge_wakeup_gpio;
struct work_struct uart_tx_lpm_work;
int break_abnormal;
int dma_enable;
struct uart_pxa_dma uart_dma;
unsigned long flags;
u32 wakeup_by_uart:1;
u32 uart_dev_suspended:1;
};
static void pxa_uart_transmit_dma_cb(void *data);
static void pxa_uart_receive_dma_cb(void *data);
static void pxa_uart_transmit_dma_start(struct uart_pxa_port *up, int count);
static void pxa_uart_receive_dma_start(struct uart_pxa_port *up);
static inline void wait_for_xmitr(struct uart_pxa_port *up);
static inline void serial_out(struct uart_pxa_port *up, int offset, int value);
static void _pxa_timer_handler(struct uart_pxa_port *up);
static void pxa_timer_handler(struct timer_list *t);
static unsigned int serial_pxa_tx_empty(struct uart_port *port);
#define PXA_TIMER_TIMEOUT (3*HZ)
#define RX_WAKELOCK_TIMEOUT 15000
static inline void stop_dma(struct uart_pxa_port *up, int read)
{
unsigned long flags;
struct uart_pxa_dma *pxa_dma = &up->uart_dma;
struct dma_chan *channel;
if (!pxa_dma->dma_init)
return;
channel = read ? pxa_dma->rxdma_chan : pxa_dma->txdma_chan;
dmaengine_terminate_all(channel);
spin_lock_irqsave(&up->port.lock, flags);
if (read)
pxa_dma->dma_status &= ~RX_DMA_RUNNING;
else
pxa_dma->dma_status &= ~TX_DMA_RUNNING;
spin_unlock_irqrestore(&up->port.lock, flags);
}
static inline unsigned int serial_in(struct uart_pxa_port *up, int offset)
{
offset <<= 2;
return readl(up->port.membase + offset);
}
static inline void serial_out(struct uart_pxa_port *up, int offset, int value)
{
offset <<= 2;
writel(value, up->port.membase + offset);
}
static void serial_pxa_enable_ms(struct uart_port *port)
{
struct uart_pxa_port *up = (struct uart_pxa_port *)port;
if (up->dma_enable)
return;
up->ier |= UART_IER_MSI;
serial_out(up, UART_IER, up->ier);
}
static void serial_pxa_stop_tx(struct uart_port *port)
{
struct uart_pxa_port *up = (struct uart_pxa_port *)port;
if (up->dma_enable) {
/*
* Do nothing.
* Here we let the hardware decide whether to stop DMA
*/
} else {
if (up->ier & UART_IER_THRI) {
up->ier &= ~UART_IER_THRI;
serial_out(up, UART_IER, up->ier);
}
}
}
static void serial_pxa_stop_rx(struct uart_port *port)
{
struct uart_pxa_port *up = (struct uart_pxa_port *)port;
if (up->dma_enable) {
if (up->ier & UART_IER_DMAE) {
spin_unlock_irqrestore(&up->port.lock, up->flags);
stop_dma(up, PXA_UART_RX);
spin_lock_irqsave(&up->port.lock, up->flags);
}
up->uart_dma.rx_stop = 1;
} else {
up->ier &= ~UART_IER_RLSI;
up->port.read_status_mask &= ~UART_LSR_DR;
serial_out(up, UART_IER, up->ier);
}
}
static inline void receive_chars(struct uart_pxa_port *up, int *status)
{
unsigned int ch, flag;
int max_count = 256;
do {
/* work around Errata #20 according to
* Intel(R) PXA27x Processor Family
* Specification Update (May 2005)
*
* Step 2
* Disable the Reciever Time Out Interrupt via IER[RTOEI]
*/
spin_lock_irqsave(&up->port.lock, up->flags);
up->ier &= ~UART_IER_RTOIE;
serial_out(up, UART_IER, up->ier);
spin_unlock_irqrestore(&up->port.lock, up->flags);
ch = serial_in(up, UART_RX);
flag = TTY_NORMAL;
up->port.icount.rx++;
if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
UART_LSR_FE | UART_LSR_OE))) {
/*
* For statistics only
*/
if (*status & UART_LSR_BI) {
*status &= ~(UART_LSR_FE | UART_LSR_PE);
up->port.icount.brk++;
/*
* We do the SysRQ and SAK checking
* here because otherwise the break
* may get masked by ignore_status_mask
* or read_status_mask.
*/
if (uart_handle_break(&up->port))
goto ignore_char;
} else if (*status & UART_LSR_PE)
up->port.icount.parity++;
else if (*status & UART_LSR_FE)
up->port.icount.frame++;
if (*status & UART_LSR_OE)
up->port.icount.overrun++;
/*
* Mask off conditions which should be ignored.
*/
*status &= up->port.read_status_mask;
#ifdef CONFIG_SERIAL_PXA_CONSOLE
if (up->port.line == up->port.cons->index) {
/* Recover the break flag from console xmit */
*status |= up->lsr_break_flag;
up->lsr_break_flag = 0;
}
#endif
if (*status & UART_LSR_BI) {
flag = TTY_BREAK;
} else if (*status & UART_LSR_PE)
flag = TTY_PARITY;
else if (*status & UART_LSR_FE)
flag = TTY_FRAME;
}
if (uart_handle_sysrq_char(&up->port, ch))
goto ignore_char;
uart_insert_char(&up->port, *status, UART_LSR_OE, ch, flag);
ignore_char:
*status = serial_in(up, UART_LSR);
} while ((*status & UART_LSR_DR) && (max_count-- > 0));
tty_flip_buffer_push(&up->port.state->port);
/* work around Errata #20 according to
* Intel(R) PXA27x Processor Family
* Specification Update (May 2005)
*
* Step 6:
* No more data in FIFO: Re-enable RTO interrupt via IER[RTOIE]
*/
spin_lock_irqsave(&up->port.lock, up->flags);
up->ier |= UART_IER_RTOIE;
serial_out(up, UART_IER, up->ier);
spin_unlock_irqrestore(&up->port.lock, up->flags);
}
static void transmit_chars(struct uart_pxa_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)) {
spin_lock_irqsave(&up->port.lock, up->flags);
serial_pxa_stop_tx(&up->port);
spin_unlock_irqrestore(&up->port.lock, up->flags);
return;
}
count = up->port.fifosize / 2;
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))
{
spin_lock_irqsave(&up->port.lock, up->flags);
serial_pxa_stop_tx(&up->port);
spin_unlock_irqrestore(&up->port.lock, up->flags);
}
}
static inline void
dma_receive_err_handler(struct uart_pxa_port *up, int *status)
{
struct tty_port *port = &up->port.state->port;
unsigned char ch;
int count = 0;
unsigned char *tmp;
unsigned int flag = TTY_NORMAL;
struct uart_pxa_dma *pxa_dma = &up->uart_dma;
struct dma_tx_state dma_state;
if (!pxa_dma->dma_init)
return;
/*
* Pause DMA channel and deal with the bytes received by DMA
*/
dmaengine_pause(pxa_dma->rxdma_chan);
dmaengine_tx_status(pxa_dma->rxdma_chan, pxa_dma->rx_cookie,
&dma_state);
count = DMA_RX_BLOCK_SIZE - dma_state.residue;
tmp = pxa_dma->rxdma_addr;
if (up->port.sysrq) {
while (count > 0) {
if (!uart_handle_sysrq_char(&up->port, *tmp)) {
uart_insert_char(&up->port, *status,
0, *tmp, flag);
up->port.icount.rx++;
}
tmp++;
count--;
}
} else {
tty_insert_flip_string(port, tmp, count);
up->port.icount.rx += count;
}
/* deal with the bytes in rx FIFO */
do {
ch = serial_in(up, UART_RX);
flag = TTY_NORMAL;
up->port.icount.rx++;
/*
* For statistics only
*/
if (*status & UART_LSR_BI) {
*status &= ~(UART_LSR_FE | UART_LSR_PE);
up->port.icount.brk++;
/*
* We do the SysRQ and SAK checking
* here because otherwise the break
* may get masked by ignore_status_mask
* or read_status_mask.
*/
if (uart_handle_break(&up->port))
goto ignore_char2;
} else if (*status & UART_LSR_PE) {
up->port.icount.parity++;
} else if (*status & UART_LSR_FE) {
up->port.icount.frame++;
}
if (*status & UART_LSR_OE)
up->port.icount.overrun++;
/*
* Mask off conditions which should be ignored.
*/
*status &= up->port.read_status_mask;
#ifdef CONFIG_SERIAL_PXA_CONSOLE
if (up->port.line == up->port.cons->index) {
/* Recover the break flag from console xmit */
*status |= up->lsr_break_flag;
up->lsr_break_flag = 0;
}
#endif
if (*status & UART_LSR_BI)
flag = TTY_BREAK;
else if (*status & UART_LSR_PE)
flag = TTY_PARITY;
else if (*status & UART_LSR_FE)
flag = TTY_FRAME;
if (!uart_handle_sysrq_char(&up->port, ch))
uart_insert_char(&up->port, *status, UART_LSR_OE,
ch, flag);
ignore_char2:
*status = serial_in(up, UART_LSR);
} while ((*status & UART_LSR_DR));
tty_schedule_flip(port);
stop_dma(up, 1);
if (pxa_dma->rx_stop)
return;
pxa_uart_receive_dma_start(up);
}
static inline void
dma_receive_chars(struct uart_pxa_port *up, int *status)
{
struct tty_port *port = &up->port.state->port;
unsigned char ch;
int max_count = 256;
int count = 0;
unsigned char *tmp;
unsigned int flag = TTY_NORMAL;
struct uart_pxa_dma *pxa_dma = &up->uart_dma;
struct dma_tx_state dma_state;
if (!pxa_dma->dma_init)
return;
/*
* Pause DMA channel and deal with the bytes received by DMA
*/
dmaengine_pause(pxa_dma->rxdma_chan);
dmaengine_tx_status(pxa_dma->rxdma_chan, pxa_dma->rx_cookie,
&dma_state);
count = DMA_RX_BLOCK_SIZE - dma_state.residue;
tmp = pxa_dma->rxdma_addr;
if (up->port.sysrq) {
while (count > 0) {
if (!uart_handle_sysrq_char(&up->port, *tmp)) {
uart_insert_char(&up->port, *status,
0, *tmp, flag);
up->port.icount.rx++;
}
tmp++;
count--;
}
} else {
tty_insert_flip_string(port, tmp, count);
up->port.icount.rx += count;
}
*status = serial_in(up, UART_LSR);
if (!(*status & UART_LSR_DR)) {
ch = serial_in(up, UART_RX);
goto done;
}
/* deal with the bytes in rx FIFO */
do {
ch = serial_in(up, UART_RX);
flag = TTY_NORMAL;
up->port.icount.rx++;
if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
UART_LSR_FE | UART_LSR_OE))) {
/*
* For statistics only
*/
if (*status & UART_LSR_BI) {
*status &= ~(UART_LSR_FE | UART_LSR_PE);
up->port.icount.brk++;
/*
* We do the SysRQ and SAK checking
* here because otherwise the break
* may get masked by ignore_status_mask
* or read_status_mask.
*/
if (uart_handle_break(&up->port))
goto ignore_char2;
} else if (*status & UART_LSR_PE) {
up->port.icount.parity++;
} else if (*status & UART_LSR_FE) {
up->port.icount.frame++;
}
if (*status & UART_LSR_OE)
up->port.icount.overrun++;
/*
* Mask off conditions which should be ignored.
*/
*status &= up->port.read_status_mask;
#ifdef CONFIG_SERIAL_PXA_CONSOLE
if (up->port.line == up->port.cons->index) {
/* Recover the break flag from console xmit */
*status |= up->lsr_break_flag;
up->lsr_break_flag = 0;
}
#endif
if (*status & UART_LSR_BI)
flag = TTY_BREAK;
else if (*status & UART_LSR_PE)
flag = TTY_PARITY;
else if (*status & UART_LSR_FE)
flag = TTY_FRAME;
}
if (!uart_handle_sysrq_char(&up->port, ch))
uart_insert_char(&up->port, *status, UART_LSR_OE,
ch, flag);
ignore_char2:
*status = serial_in(up, UART_LSR);
} while ((*status & UART_LSR_DR) && (max_count-- > 0));
done:
tty_schedule_flip(port);
stop_dma(up, 1);
if (pxa_dma->rx_stop)
return;
pxa_uart_receive_dma_start(up);
}
static void serial_pxa_start_tx(struct uart_port *port)
{
struct uart_pxa_port *up = (struct uart_pxa_port *)port;
if (up->dma_enable) {
up->uart_dma.tx_stop = 0;
tasklet_schedule(&up->uart_dma.tklet);
} else {
if (!(up->ier & UART_IER_THRI)) {
up->ier |= UART_IER_THRI;
serial_out(up, UART_IER, up->ier);
}
}
}
/* should hold up->port.lock */
static inline void check_modem_status(struct uart_pxa_port *up)
{
int status;
status = serial_in(up, UART_MSR);
if ((status & UART_MSR_ANY_DELTA) == 0)
return;
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);
}
/*
* This handles the interrupt from one port.
*/
static inline irqreturn_t serial_pxa_irq(int irq, void *dev_id)
{
struct uart_pxa_port *up = dev_id;
unsigned int iir, lsr;
iir = serial_in(up, UART_IIR);
if (iir & UART_IIR_NO_INT)
return IRQ_NONE;
/* timer is not active */
if (!mod_timer(&up->pxa_timer, jiffies + PXA_TIMER_TIMEOUT))
pm_qos_update_request(&up->qos_idle[PXA_UART_RX],
up->lpm_qos);
lsr = serial_in(up, UART_LSR);
if (up->dma_enable) {
/* we only need to deal with FIFOE here */
if (lsr & UART_LSR_FIFOE)
dma_receive_err_handler(up, &lsr);
if (iir & UART_IIR_TOD)
dma_receive_chars(up, &lsr);
} else {
if (lsr & UART_LSR_DR) {
receive_chars(up, &lsr);
/* Avoid suspend within 3 seconds. */
if (up->edge_wakeup_gpio >= 0)
pm_wakeup_event(up->port.dev, RX_WAKELOCK_TIMEOUT);
}
check_modem_status(up);
if (lsr & UART_LSR_THRE) {
transmit_chars(up);
/* wait Tx empty */
while (!serial_pxa_tx_empty((struct uart_port *)dev_id))
;
}
}
return IRQ_HANDLED;
}
static unsigned int serial_pxa_tx_empty(struct uart_port *port)
{
struct uart_pxa_port *up = (struct uart_pxa_port *)port;
unsigned long flags;
unsigned int ret;
spin_lock_irqsave(&up->port.lock, flags);
if (up->dma_enable) {
if (up->ier & UART_IER_DMAE) {
if (up->uart_dma.dma_status & TX_DMA_RUNNING) {
spin_unlock_irqrestore(&up->port.lock, flags);
return 0;
}
}
}
ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
spin_unlock_irqrestore(&up->port.lock, flags);
return ret;
}
static unsigned int serial_pxa_get_mctrl(struct uart_port *port)
{
struct uart_pxa_port *up = (struct uart_pxa_port *)port;
unsigned char status;
unsigned int ret;
status = serial_in(up, UART_MSR);
ret = 0;
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_pxa_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
struct uart_pxa_port *up = (struct uart_pxa_port *)port;
unsigned int mcr = 0;
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;
mcr |= up->mcr;
serial_out(up, UART_MCR, mcr);
}
static void serial_pxa_break_ctl(struct uart_port *port, int break_state)
{
struct uart_pxa_port *up = (struct uart_pxa_port *)port;
unsigned long flags;
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);
}
static void pxa_uart_transmit_dma_start(struct uart_pxa_port *up, int count)
{
struct uart_pxa_dma *pxa_dma = &up->uart_dma;
struct dma_slave_config slave_config;
int ret;
if (!pxa_dma->txdma_chan) {
dev_err(up->port.dev, "tx dma channel is not initialized\n");
return;
}
slave_config.direction = DMA_MEM_TO_DEV;
slave_config.dst_addr = up->port.mapbase;
slave_config.dst_maxburst = 32;
slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
if (pxa_dma->drcmr_tx)
slave_config.slave_id = pxa_dma->drcmr_tx;
else
slave_config.slave_id = 0;
ret = dmaengine_slave_config(pxa_dma->txdma_chan, &slave_config);
if (ret) {
dev_err(up->port.dev,
"%s: dmaengine slave config err.\n", __func__);
return;
}
pxa_dma->tx_size = count;
pxa_dma->tx_desc = dmaengine_prep_slave_single(pxa_dma->txdma_chan,
pxa_dma->txdma_addr_phys, count, DMA_MEM_TO_DEV, 0);
if(pxa_dma->tx_desc == NULL) {
dev_err(up->port.dev,
"%s: Unable to get desc for Tx\n", __func__);
return;
}
pxa_dma->tx_desc->callback = pxa_uart_transmit_dma_cb;
pxa_dma->tx_desc->callback_param = up;
pxa_dma->tx_cookie = dmaengine_submit(pxa_dma->tx_desc);
pm_qos_update_request(&up->qos_idle[PXA_UART_TX],
up->lpm_qos);
dma_async_issue_pending(pxa_dma->txdma_chan);
}
static void pxa_uart_receive_dma_start(struct uart_pxa_port *up)
{
unsigned long flags;
struct uart_pxa_dma *uart_dma = &up->uart_dma;
struct dma_slave_config slave_config;
int ret;
if (!uart_dma->rxdma_chan) {
dev_err(up->port.dev, "rx dma channel is not initialized\n");
return;
}
spin_lock_irqsave(&up->port.lock, flags);
if (uart_dma->dma_status & RX_DMA_RUNNING) {
spin_unlock_irqrestore(&up->port.lock, flags);
return;
}
uart_dma->dma_status |= RX_DMA_RUNNING;
spin_unlock_irqrestore(&up->port.lock, flags);
slave_config.direction = DMA_DEV_TO_MEM;
slave_config.src_addr = up->port.mapbase;
slave_config.src_maxburst = 16;
slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
if (uart_dma->drcmr_rx)
slave_config.slave_id = uart_dma->drcmr_rx;
else
slave_config.slave_id = 0;
ret = dmaengine_slave_config(uart_dma->rxdma_chan, &slave_config);
if (ret) {
dev_err(up->port.dev,
"%s: dmaengine slave config err.\n", __func__);
return;
}
uart_dma->rx_desc = dmaengine_prep_slave_single(uart_dma->rxdma_chan,
uart_dma->rxdma_addr_phys, DMA_RX_BLOCK_SIZE, DMA_DEV_TO_MEM, 0);
if(uart_dma->rx_desc == NULL) {
dev_err(up->port.dev,
"%s: Unable to get desc for Rx\n", __func__);
return;
}
uart_dma->rx_desc->callback = pxa_uart_receive_dma_cb;
uart_dma->rx_desc->callback_param = up;
uart_dma->rx_cookie = dmaengine_submit(uart_dma->rx_desc);
dma_async_issue_pending(uart_dma->rxdma_chan);
}
static void pxa_uart_receive_dma_cb(void *data)
{
unsigned long flags;
struct uart_pxa_port *up = (struct uart_pxa_port *)data;
struct uart_pxa_dma *pxa_dma = &up->uart_dma;
struct tty_port *port = &up->port.state->port;
unsigned int count;
unsigned char *tmp = pxa_dma->rxdma_addr;
struct dma_tx_state dma_state;
if (!mod_timer(&up->pxa_timer, jiffies + PXA_TIMER_TIMEOUT))
pm_qos_update_request(&up->qos_idle[PXA_UART_RX],
up->lpm_qos);
dmaengine_tx_status(pxa_dma->rxdma_chan, pxa_dma->rx_cookie,
&dma_state);
count = DMA_RX_BLOCK_SIZE - dma_state.residue;
if (up->port.sysrq) {
while (count > 0) {
if (!uart_handle_sysrq_char(&up->port, *tmp)) {
tty_insert_flip_char(port, *tmp, TTY_NORMAL);
up->port.icount.rx++;
}
tmp++;
count--;
}
} else {
tty_insert_flip_string(port, tmp, count);
up->port.icount.rx += count;
}
tty_flip_buffer_push(port);
spin_lock_irqsave(&up->port.lock, flags);
/*
* DMA_RUNNING flag should be clear only after
* all dma interface operation completed
*/
pxa_dma->dma_status &= ~RX_DMA_RUNNING;
spin_unlock_irqrestore(&up->port.lock, flags);
if (pxa_dma->rx_stop)
return;
pxa_uart_receive_dma_start(up);
if (up->edge_wakeup_gpio >= 0)
pm_wakeup_event(up->port.dev, RX_WAKELOCK_TIMEOUT);
}
static void pxa_uart_transmit_dma_cb(void *data)
{
struct uart_pxa_port *up = (struct uart_pxa_port *)data;
struct uart_pxa_dma *pxa_dma = &up->uart_dma;
struct circ_buf *xmit = &up->port.state->xmit;
if (dma_async_is_tx_complete(pxa_dma->txdma_chan, pxa_dma->tx_cookie,
NULL, NULL) == DMA_COMPLETE)
schedule_work(&up->uart_tx_lpm_work);
spin_lock_irqsave(&up->port.lock, up->flags);
/*
* DMA_RUNNING flag should be clear only after
* all dma interface operation completed
*/
pxa_dma->dma_status &= ~TX_DMA_RUNNING;
spin_unlock_irqrestore(&up->port.lock, up->flags);
/* if tx stop, stop transmit DMA and return */
if (pxa_dma->tx_stop)
return;
if (up->port.x_char) {
serial_out(up, UART_TX, up->port.x_char);
up->port.icount.tx++;
up->port.x_char = 0;
}
if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
uart_write_wakeup(&up->port);
if (!uart_circ_empty(xmit))
tasklet_schedule(&pxa_dma->tklet);
}
static void pxa_uart_dma_init(struct uart_pxa_port *up)
{
struct uart_pxa_dma *pxa_dma = &up->uart_dma;
dma_cap_mask_t mask;
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
if (NULL == pxa_dma->rxdma_chan) {
pxa_dma->rxdma_chan = dma_request_slave_channel(up->port.dev,
"rx");
if (IS_ERR_OR_NULL(pxa_dma->rxdma_chan)) {
dev_WARN_ONCE(up->port.dev, 1,
"failed to request rx dma channel\n");
goto out;
}
}
if (NULL == pxa_dma->txdma_chan) {
pxa_dma->txdma_chan = dma_request_slave_channel(up->port.dev,
"tx");
if (IS_ERR_OR_NULL(pxa_dma->txdma_chan)) {
dev_WARN_ONCE(up->port.dev, 1,
"failed to request tx dma channel\n");
goto err_txdma;
}
}
if (NULL == pxa_dma->txdma_addr) {
pxa_dma->txdma_addr = dma_alloc_coherent(up->port.dev,
DMA_BLOCK, &pxa_dma->txdma_addr_phys, GFP_KERNEL);
if (!pxa_dma->txdma_addr) {
dev_WARN_ONCE(up->port.dev, 1,
"failed to allocate tx dma memory\n");
goto txdma_err_alloc;
}
}
if (NULL == pxa_dma->rxdma_addr) {
pxa_dma->rxdma_addr = dma_alloc_coherent(up->port.dev,
DMA_RX_BLOCK_SIZE, &pxa_dma->rxdma_addr_phys, GFP_KERNEL);
if (!pxa_dma->rxdma_addr) {
dev_WARN_ONCE(up->port.dev, 1,
"failed to allocate rx dma memory\n");
goto rxdma_err_alloc;
}
}
#ifdef CONFIG_PM
pxa_dma->tx_buf_save = kmalloc(DMA_BLOCK, GFP_KERNEL);
if (!pxa_dma->tx_buf_save) {
goto buf_err_alloc;
}
#endif
pxa_dma->dma_status = 0;
pxa_dma->dma_init = true;
return;
#ifdef CONFIG_PM
buf_err_alloc:
kfree(pxa_dma->rxdma_addr);
pxa_dma->rxdma_addr = NULL;
#endif
rxdma_err_alloc:
dma_free_coherent(up->port.dev, DMA_BLOCK, pxa_dma->txdma_addr,
pxa_dma->txdma_addr_phys);
pxa_dma->txdma_addr = NULL;
txdma_err_alloc:
dma_release_channel(pxa_dma->txdma_chan);
pxa_dma->txdma_chan = NULL;
err_txdma:
dma_release_channel(pxa_dma->rxdma_chan);
pxa_dma->rxdma_chan = NULL;
out:
pxa_dma->dma_init = false;
return;
}
static void pxa_uart_dma_uninit(struct uart_pxa_port *up)
{
struct uart_pxa_dma *pxa_dma;
pxa_dma = &up->uart_dma;
stop_dma(up, PXA_UART_TX);
stop_dma(up, PXA_UART_RX);
pxa_dma->dma_init = false;
#ifdef CONFIG_PM
kfree(pxa_dma->tx_buf_save);
#endif
if (pxa_dma->txdma_chan != NULL) {
dma_release_channel(pxa_dma->txdma_chan);
pxa_dma->txdma_chan = NULL;
}
if (pxa_dma->txdma_addr != NULL) {
dma_free_coherent(up->port.dev, DMA_BLOCK, pxa_dma->txdma_addr,
pxa_dma->txdma_addr_phys);
pxa_dma->txdma_addr = NULL;
}
if (pxa_dma->rxdma_chan != NULL) {
dma_release_channel(pxa_dma->rxdma_chan);
pxa_dma->rxdma_chan = NULL;
}
if (pxa_dma->rxdma_addr != NULL) {
dma_free_coherent(up->port.dev, DMA_RX_BLOCK_SIZE, pxa_dma->rxdma_addr,
pxa_dma->rxdma_addr_phys);
pxa_dma->rxdma_addr = NULL;
}
}
static void uart_task_action(unsigned long data)
{
struct uart_pxa_port *up = (struct uart_pxa_port *)data;
struct circ_buf *xmit = &up->port.state->xmit;
unsigned char *tmp = up->uart_dma.txdma_addr;
unsigned long flags;
int count = 0, c;
/* if the tx is stop or the uart device is suspended, just return. */
/* if port is shutdown,just return. */
if (up->uart_dma.tx_stop || up->port.suspended)
return;
spin_lock_irqsave(&up->port.lock, flags);
if (up->uart_dma.dma_status & TX_DMA_RUNNING) {
spin_unlock_irqrestore(&up->port.lock, flags);
return;
}
up->uart_dma.dma_status |= TX_DMA_RUNNING;
while (1) {
c = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
if (c <= 0)
break;
memcpy(tmp, xmit->buf + xmit->tail, c);
xmit->tail = (xmit->tail + c) & (UART_XMIT_SIZE - 1);
tmp += c;
count += c;
up->port.icount.tx += c;
}
spin_unlock_irqrestore(&up->port.lock, flags);
pr_debug("count =%d", count);
pxa_uart_transmit_dma_start(up, count);
}
static int serial_pxa_startup(struct uart_port *port)
{
struct uart_pxa_port *up = (struct uart_pxa_port *)port;
unsigned long flags;
if (port->line == 3) /* HWUART */
up->mcr |= UART_MCR_AFE;
else
up->mcr = 0;
up->port.uartclk = clk_get_rate(up->clk);
enable_irq(up->port.irq);
/*
* Clear the FIFO buffers and disable them.
* (they will be reenabled in set_termios())
*/
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);
/*
* Clear the interrupt registers.
*/
(void) serial_in(up, UART_LSR);
(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);
up->port.mctrl |= TIOCM_OUT2;
serial_pxa_set_mctrl(&up->port, up->port.mctrl);
spin_unlock_irqrestore(&up->port.lock, flags);
/*
* 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.
*/
if (up->dma_enable) {
pr_pm_debug("uart work in dma mode\n");
pxa_uart_dma_init(up);
up->uart_dma.rx_stop = 0;
pxa_uart_receive_dma_start(up);
tasklet_init(&up->uart_dma.tklet, uart_task_action,
(unsigned long)up);
}
spin_lock_irqsave(&up->port.lock, flags);
if (up->dma_enable) {
up->ier = UART_IER_DMAE | UART_IER_UUE | UART_IER_RTOIE;
} else {
up->ier = UART_IER_RLSI | UART_IER_RDI |
UART_IER_RTOIE | UART_IER_UUE;
}
serial_out(up, UART_IER, up->ier);
spin_unlock_irqrestore(&up->port.lock, flags);
/*
* And clear the interrupt registers again for luck.
*/
(void) serial_in(up, UART_LSR);
(void) serial_in(up, UART_RX);
(void) serial_in(up, UART_IIR);
(void) serial_in(up, UART_MSR);
return 0;
}
static void serial_pxa_shutdown(struct uart_port *port)
{
struct uart_pxa_port *up = (struct uart_pxa_port *)port;
unsigned long flags;
unsigned int tmp = 0;
unsigned int timeout = 0x100000;
if (up->ier & UART_IER_DMAE && up->uart_dma.dma_init) {
while (dma_async_is_tx_complete(up->uart_dma.txdma_chan,
up->uart_dma.tx_cookie, NULL, NULL)
!= DMA_COMPLETE && (timeout-- > 0))
udelay(1);
BUG_ON(timeout == 0);
}
disable_irq(up->port.irq);
if (up->dma_enable) {
tasklet_kill(&up->uart_dma.tklet);
up->uart_dma.tx_stop = 1;
up->uart_dma.rx_stop = 1;
pxa_uart_dma_uninit(up);
}
flush_work(&up->uart_tx_lpm_work);
/*
* Disable interrupts from this port
*/
spin_lock_irqsave(&up->port.lock, flags);
up->ier = 0;
serial_out(up, UART_IER, 0);
up->port.mctrl &= ~TIOCM_OUT2;
tmp = serial_in(up, UART_MCR);
tmp &= ~TIOCM_OUT2;
serial_out(up, UART_MCR, tmp);
spin_unlock_irqrestore(&up->port.lock, flags);
spin_lock_irqsave(&up->port.lock, flags);
up->port.mctrl &= ~TIOCM_OUT2;
serial_pxa_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_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
UART_FCR_CLEAR_RCVR |
UART_FCR_CLEAR_XMIT);
serial_out(up, UART_FCR, 0);
}
static int pxa_set_baudrate_clk(struct uart_port *port, unsigned int baud)
{
struct uart_pxa_port *up = (struct uart_pxa_port *)port;
unsigned long rate;
int ret;
switch (baud) {
case 500000:
case 1000000:
case 1500000:
case 3000000:
rate = 48000000; /* from 78mhz(1803/1828), or from uart_pll2(1806/1903) */
break;
case 9600:
case 38400:
case 57600:
case 115200:
case 230400:
case 460800:
case 576000:
case 921600:
case 1152000:
case 1842000:
case 3500000:
if(cpu_is_asr1828() || cpu_is_asr1901() || cpu_is_asr1906())
rate = 58500000;
else
rate = 57600000;
break;
case 2000000:
case 4000000:
rate = 64000000; /* from 78m, uart pll1 */
break;
case 2500000:
rate = 40000000; /* from 78m, uart pll1 */
break;
default:
rate = 14740000; /* from 78m, uart pll1 */
break;
}
/* For one target baudrate, the quot is figured out
* by formula [quot] = clk_rate / 16 / baudrate, and
* choose the closest integral value above zero.
* So for different clk source, the real baudrate is
* baudrate = clk_rate / 16 / [quot]. */
ret = clk_set_rate(up->clk, rate);
if (ret < 0) {
dev_err(port->dev,
"Failed to set clk rate %lu\n", rate);
return ret;
}
up->port.uartclk = clk_get_rate(up->clk);
return 0;
}
static void
serial_pxa_set_termios(struct uart_port *port, struct ktermios *termios,
struct ktermios *old)
{
struct uart_pxa_port *up = (struct uart_pxa_port *)port;
unsigned char cval, fcr = 0;
unsigned long flags;
unsigned int baud, quot;
unsigned int dll;
int ret;
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, PXA_MAX_BAUD*16*4/16);
if (!baud)
baud = 115200;
ret = pxa_set_baudrate_clk(port, baud);
if (ret < 0) {
dev_err(port->dev, "Failed to set baud rate clk: %d\n", ret);
return;
}
quot = uart_get_divisor(port, baud);
if (up->dma_enable) {
fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR32 |
UART_FCR_PXA_TRAIL;
fcr &= ~UART_FCR_PXA_BUS32;
} else {
if ((up->port.uartclk / quot) < (2400 * 16))
fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR1;
else if ((up->port.uartclk / quot) < (230400 * 16))
fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR8;
else if ((up->port.uartclk / quot) < (921600 * 16))
fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR32;
else
fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR16;
}
/*
* Ok, we're now changing the port state. Do it with
* interrupts disabled.
*/
spin_lock_irqsave(&up->port.lock, flags);
if (baud > PXA_MAX_BAUD)
up->ier |= UART_IER_HSE;
else
up->ier &= ~UART_IER_HSE;
/*
* Ensure the port will be enabled.
* This is required especially for serial console.
*/
up->ier |= UART_IER_UUE;
/*
* 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 & (IGNBRK | 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;
/*
* CTS flow control flag and modem status interrupts
*/
if (!up->dma_enable) {
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);
if (termios->c_cflag & CRTSCTS)
up->mcr |= UART_MCR_AFE;
else
up->mcr &= ~UART_MCR_AFE;
serial_out(up, UART_LCR, cval | UART_LCR_DLAB); /* set DLAB */
serial_out(up, UART_DLL, quot & 0xff); /* LS of divisor */
/*
* work around Errata #75 according to Intel(R) PXA27x Processor Family
* Specification Update (Nov 2005)
*/
dll = serial_in(up, UART_DLL);
WARN_ON(dll != (quot & 0xff));
serial_out(up, UART_DLM, quot >> 8); /* MS of divisor */
serial_out(up, UART_LCR, cval); /* reset DLAB */
up->lcr = cval; /* Save LCR */
serial_pxa_set_mctrl(&up->port, up->port.mctrl);
serial_out(up, UART_FCR, fcr);
spin_unlock_irqrestore(&up->port.lock, flags);
}
static void
serial_pxa_pm(struct uart_port *port, unsigned int state,
unsigned int oldstate)
{
struct uart_pxa_port *up = (struct uart_pxa_port *)port;
if (!state)
clk_prepare_enable(up->clk);
else
clk_disable_unprepare(up->clk);
}
static void serial_pxa_release_port(struct uart_port *port)
{
}
static int serial_pxa_request_port(struct uart_port *port)
{
return 0;
}
static void serial_pxa_config_port(struct uart_port *port, int flags)
{
struct uart_pxa_port *up = (struct uart_pxa_port *)port;
up->port.type = PORT_PXA;
}
static int
serial_pxa_verify_port(struct uart_port *port, struct serial_struct *ser)
{
/* we don't want the core code to modify any port params */
return -EINVAL;
}
static const char *
serial_pxa_type(struct uart_port *port)
{
struct uart_pxa_port *up = (struct uart_pxa_port *)port;
return up->name;
}
static struct uart_pxa_port *serial_pxa_ports[4];
static struct uart_driver serial_pxa_reg;
#ifdef CONFIG_SERIAL_PXA_CONSOLE
#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
/*
* Wait for transmitter & holding register to empty
*/
static void wait_for_xmitr(struct uart_pxa_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;
while (--tmout &&
((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
udelay(1);
}
}
static void serial_pxa_console_putchar(struct uart_port *port, int ch)
{
struct uart_pxa_port *up = (struct uart_pxa_port *)port;
wait_for_xmitr(up);
serial_out(up, UART_TX, ch);
}
/*
* Print a string to the serial port trying not to disturb
* any possible real use of the port...
*
* The console_lock must be held when we get here.
*/
static void
serial_pxa_console_write(struct console *co, const char *s, unsigned int count)
{
struct uart_pxa_port *up = serial_pxa_ports[co->index];
unsigned int ier;
unsigned long flags;
int locked = 1;
clk_enable(up->clk);
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, UART_IER_UUE);
uart_console_write(&up->port, s, count, serial_pxa_console_putchar);
/*
* Finally, wait for transmitter to become empty
* and restore the IER
*/
wait_for_xmitr(up);
serial_out(up, UART_IER, ier);
if (locked)
spin_unlock(&up->port.lock);
local_irq_restore(flags);
clk_disable(up->clk);
}
#ifdef CONFIG_CONSOLE_POLL
/*
* Console polling routines for writing and reading from the uart while
* in an interrupt or debug context.
*/
static int serial_pxa_get_poll_char(struct uart_port *port)
{
struct uart_pxa_port *up = (struct uart_pxa_port *)port;
unsigned char lsr = serial_in(up, UART_LSR);
while (!(lsr & UART_LSR_DR))
lsr = serial_in(up, UART_LSR);
return serial_in(up, UART_RX);
}
static void serial_pxa_put_poll_char(struct uart_port *port,
unsigned char c)
{
unsigned int ier;
struct uart_pxa_port *up = (struct uart_pxa_port *)port;
/*
* First save the IER then disable the interrupts
*/
ier = serial_in(up, UART_IER);
serial_out(up, UART_IER, UART_IER_UUE);
wait_for_xmitr(up);
/*
* Send the character out.
* If a LF, also do CR...
*/
serial_out(up, UART_TX, c);
if (c == 10) {
wait_for_xmitr(up);
serial_out(up, UART_TX, 13);
}
/*
* Finally, wait for transmitter to become empty
* and restore the IER
*/
wait_for_xmitr(up);
serial_out(up, UART_IER, ier);
}
#endif /* CONFIG_CONSOLE_POLL */
static int __init
serial_pxa_console_setup(struct console *co, char *options)
{
struct uart_pxa_port *up;
int baud = 9600;
int bits = 8;
int parity = 'n';
int flow = 'n';
if (co->index == -1 || co->index >= serial_pxa_reg.nr)
co->index = 0;
up = serial_pxa_ports[co->index];
if (!up)
return -ENODEV;
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_pxa_console = {
.name = "ttyS",
.write = serial_pxa_console_write,
.device = uart_console_device,
.setup = serial_pxa_console_setup,
.flags = CON_PRINTBUFFER,
.index = -1,
.data = &serial_pxa_reg,
};
#define PXA_CONSOLE &serial_pxa_console
#else
#define PXA_CONSOLE NULL
#endif
static const struct uart_ops serial_pxa_pops = {
.tx_empty = serial_pxa_tx_empty,
.set_mctrl = serial_pxa_set_mctrl,
.get_mctrl = serial_pxa_get_mctrl,
.stop_tx = serial_pxa_stop_tx,
.start_tx = serial_pxa_start_tx,
.stop_rx = serial_pxa_stop_rx,
.enable_ms = serial_pxa_enable_ms,
.break_ctl = serial_pxa_break_ctl,
.startup = serial_pxa_startup,
.shutdown = serial_pxa_shutdown,
.set_termios = serial_pxa_set_termios,
.pm = serial_pxa_pm,
.type = serial_pxa_type,
.release_port = serial_pxa_release_port,
.request_port = serial_pxa_request_port,
.config_port = serial_pxa_config_port,
.verify_port = serial_pxa_verify_port,
#if defined(CONFIG_CONSOLE_POLL) && defined(CONFIG_SERIAL_PXA_CONSOLE)
.poll_get_char = serial_pxa_get_poll_char,
.poll_put_char = serial_pxa_put_poll_char,
#endif
};
static struct uart_driver serial_pxa_reg = {
.owner = THIS_MODULE,
.driver_name = "PXA serial",
.dev_name = "ttyS",
.major = TTY_MAJOR,
.minor = 64,
.nr = 4,
.cons = PXA_CONSOLE,
};
#ifdef CONFIG_PM
static int serial_pxa_suspend(struct device *dev)
{
struct uart_pxa_port *sport = dev_get_drvdata(dev);
struct uart_pxa_dma *pxa_dma = &sport->uart_dma;
struct dma_tx_state dma_state;
unsigned char tmp[256];
int fifo_cnt, cnt = 0;
if (!sport)
return 0;
if (!console_suspend_enabled)
goto out;
if (sport && (sport->ier & UART_IER_DMAE)) {
int sent = 0;
unsigned long flags;
local_irq_save(flags);
/*
* tx stop and suspend and when resume,
* tx startup would be called and set it to 0
*/
pxa_dma->tx_stop = 1;
pxa_dma->rx_stop = 1;
pxa_dma->tx_saved_len = 0;
if (dma_async_is_tx_complete(pxa_dma->txdma_chan,
pxa_dma->tx_cookie, NULL, NULL)
!= DMA_COMPLETE) {
dmaengine_pause(pxa_dma->txdma_chan);
udelay(100);
dmaengine_tx_status(pxa_dma->txdma_chan,
pxa_dma->tx_cookie, &dma_state);
sent = pxa_dma->tx_size - dma_state.residue;
pxa_dma->tx_saved_len = dma_state.residue;
memcpy(pxa_dma->tx_buf_save, pxa_dma->txdma_addr + sent,
dma_state.residue);
stop_dma(sport, PXA_UART_TX);
}
if (dma_async_is_tx_complete(pxa_dma->rxdma_chan,
pxa_dma->rx_cookie, NULL, NULL)
!= DMA_COMPLETE) {
/* before stop receive, de-assert RTS */
spin_lock(&sport->port.lock);
serial_pxa_set_mctrl(&sport->port, sport->port.mctrl & ~TIOCM_RTS);
spin_unlock(&sport->port.lock);
udelay(100);
dmaengine_pause(pxa_dma->rxdma_chan);
udelay(100);
pxa_uart_receive_dma_cb(sport);
stop_dma(sport, PXA_UART_RX);
/* fetch the trailing bytes from FIFO */
fifo_cnt = serial_in(sport, UART_FOR);
while (fifo_cnt > 0) {
*(tmp + cnt) = serial_in(sport, UART_RX) & 0xff;
cnt++;
fifo_cnt = serial_in(sport, UART_FOR);
}
if (cnt > 0) {
tty_insert_flip_string(&sport->port.state->port, tmp, cnt);
sport->port.icount.rx += cnt;
tty_flip_buffer_push(&sport->port.state->port);
}
}
local_irq_restore(flags);
}
if (sport)
uart_suspend_port(&serial_pxa_reg, &sport->port);
/* Remove uart rx constraint which will block system entering D1p. */
if (del_timer_sync(&sport->pxa_timer))
_pxa_timer_handler(sport);
out:
sport->uart_dev_suspended = 1;
sport->wakeup_by_uart = 0;
return 0;
}
static int serial_pxa_resume(struct device *dev)
{
struct uart_pxa_port *sport = dev_get_drvdata(dev);
struct uart_pxa_dma *pxa_dma = &sport->uart_dma;
if (!sport)
return 0;
if (!console_suspend_enabled)
goto out;
if (sport)
uart_resume_port(&serial_pxa_reg, &sport->port);
if (sport && (sport->ier & UART_IER_DMAE)) {
pxa_dma->tx_stop = 0;
pxa_dma->rx_stop = 0;
if (pxa_dma->tx_saved_len > 0) {
/*
* if this transmit is not finished, we should stop
* new transmit from user space.
*/
memcpy(pxa_dma->txdma_addr, pxa_dma->tx_buf_save,
pxa_dma->tx_saved_len);
pxa_uart_transmit_dma_start(sport,
pxa_dma->tx_saved_len);
} else {
tasklet_schedule(&pxa_dma->tklet);
}
pxa_uart_receive_dma_start(sport);
}
out:
sport->uart_dev_suspended = 0;
if (sport->wakeup_by_uart)
pm_wakeup_event(sport->port.dev, RX_WAKELOCK_TIMEOUT);
return 0;
}
static const struct dev_pm_ops serial_pxa_pm_ops = {
.suspend = serial_pxa_suspend,
.resume = serial_pxa_resume,
};
#endif
static void _pxa_timer_handler(struct uart_pxa_port *up)
{
pm_qos_update_request(&up->qos_idle[PXA_UART_RX],
PM_QOS_CPUIDLE_BLOCK_DEFAULT_VALUE);
}
static void pxa_timer_handler(struct timer_list *t)
{
struct uart_pxa_port *up = from_timer(up, t, pxa_timer);
_pxa_timer_handler(up);
}
static void uart_tx_lpm_handler(struct work_struct *work)
{
struct uart_pxa_port *up =
container_of(work, struct uart_pxa_port, uart_tx_lpm_work);
/* Polling until TX FIFO is empty */
while(!(serial_in(up, UART_LSR) & UART_LSR_TEMT))
msleep(1);
pm_qos_update_request(&up->qos_idle[PXA_UART_TX],
PM_QOS_CPUIDLE_BLOCK_DEFAULT_VALUE);
}
static void uart_edge_wakeup_handler(int gpio, void *data)
{
struct uart_pxa_port *up = (struct uart_pxa_port *)data;
if (!up->uart_dev_suspended)
pm_wakeup_event(up->port.dev, RX_WAKELOCK_TIMEOUT);
up->wakeup_by_uart = 1;
if (!mod_timer(&up->pxa_timer, jiffies + PXA_TIMER_TIMEOUT))
pm_qos_update_request(&up->qos_idle[PXA_UART_RX],
up->lpm_qos);
}
static const struct of_device_id serial_pxa_dt_ids[] = {
{ .compatible = "asr,pxa-uart", },
{ .compatible = "asr,mmp-uart", },
{}
};
static int serial_pxa_probe_dt(struct platform_device *pdev,
struct uart_pxa_port *sport)
{
struct device_node *np = pdev->dev.of_node;
struct uart_pxa_dma *pxa_dma = &sport->uart_dma;
int ret, gpio;
u32 drcmr_rx;
u32 drcmr_tx;
if (!np)
return 1;
/* Get Rx DMA mapping value */
if (!of_property_read_u32(np, "uart-drcmr-rx", &drcmr_rx)){
pxa_dma->drcmr_rx = drcmr_rx;
/* Get Tx DMA mapping value */
if (!of_property_read_u32(np, "uart-drcmr-tx", &drcmr_tx)){
pxa_dma->drcmr_tx = drcmr_tx;
sport->dma_enable = 1;
}
}
ret = of_alias_get_id(np, "serial");
if (ret < 0) {
dev_err(&pdev->dev, "failed to get alias id, errno %d\n", ret);
return ret;
}
sport->port.line = ret;
if (of_property_read_u32(np, "lpm-qos", &sport->lpm_qos)) {
dev_err(&pdev->dev, "cannot find lpm-qos in device tree\n");
return -EINVAL;
}
gpio = of_get_named_gpio(np, "edge-wakeup-gpio", 0);
if (unlikely(gpio < 0)) {
dev_info(&pdev->dev, "no edge-wakeup-gpio defined\n");
sport->edge_wakeup_gpio = -1;
} else {
sport->edge_wakeup_gpio = gpio;
}
of_property_read_u32(np, "break-abnormal", &sport->break_abnormal);
return 0;
}
static int serial_pxa_probe(struct platform_device *dev)
{
struct uart_pxa_port *sport;
struct resource *mmres, *irqres;
struct uart_pxa_dma *pxa_dma;
int ret;
mmres = platform_get_resource(dev, IORESOURCE_MEM, 0);
irqres = platform_get_resource(dev, IORESOURCE_IRQ, 0);
if (!mmres || !irqres)
return -ENODEV;
sport = kzalloc(sizeof(struct uart_pxa_port), GFP_KERNEL);
if (!sport)
return -ENOMEM;
sport->clk = clk_get(&dev->dev, NULL);
if (IS_ERR(sport->clk)) {
ret = PTR_ERR(sport->clk);
goto err_free;
}
ret = clk_prepare(sport->clk);
if (ret) {
clk_put(sport->clk);
goto err_free;
}
sport->port.type = PORT_PXA;
sport->port.iotype = UPIO_MEM;
sport->port.mapbase = mmres->start;
sport->port.irq = irqres->start;
sport->port.fifosize = 64;
sport->port.ops = &serial_pxa_pops;
sport->port.dev = &dev->dev;
sport->port.flags = UPF_IOREMAP | UPF_BOOT_AUTOCONF;
sport->port.uartclk = clk_get_rate(sport->clk);
spin_lock_init(&sport->port.lock);
pxa_dma = &sport->uart_dma;
pxa_dma->drcmr_rx = 0;
pxa_dma->drcmr_tx = 0;
pxa_dma->txdma_chan = NULL;
pxa_dma->rxdma_chan = NULL;
pxa_dma->txdma_addr = NULL;
pxa_dma->rxdma_addr = NULL;
pxa_dma->dma_init = false;
sport->dma_enable = 0;
sport->edge_wakeup_gpio = -1;
ret = serial_pxa_probe_dt(dev, sport);
if (ret > 0)
sport->port.line = dev->id;
else if (ret < 0)
goto err_clk;
if (sport->port.line >= ARRAY_SIZE(serial_pxa_ports)) {
dev_err(&dev->dev, "serial%d out of range\n", sport->port.line);
ret = -EINVAL;
goto err_clk;
}
snprintf(sport->name, PXA_NAME_LEN - 1, "UART%d", sport->port.line + 1);
sport->qos_idle[PXA_UART_TX].name = kasprintf(GFP_KERNEL,
"%s%s", "tx", sport->name);
if (!sport->qos_idle[PXA_UART_TX].name) {
ret = -ENOMEM;
goto err_clk;
}
sport->qos_idle[PXA_UART_RX].name = kasprintf(GFP_KERNEL,
"%s%s", "rx", sport->name);
if (!sport->qos_idle[PXA_UART_RX].name) {
ret = -ENOMEM;
kfree(sport->qos_idle[PXA_UART_TX].name);
goto err_clk;
}
pm_qos_add_request(&sport->qos_idle[PXA_UART_TX], PM_QOS_CPUIDLE_BLOCK,
PM_QOS_CPUIDLE_BLOCK_DEFAULT_VALUE);
pm_qos_add_request(&sport->qos_idle[PXA_UART_RX], PM_QOS_CPUIDLE_BLOCK,
PM_QOS_CPUIDLE_BLOCK_DEFAULT_VALUE);
if (sport->edge_wakeup_gpio >= 0) {
device_init_wakeup(&dev->dev, 1);
ret = request_mfp_edge_wakeup(sport->edge_wakeup_gpio,
uart_edge_wakeup_handler,
sport, &dev->dev);
if (ret) {
dev_err(&dev->dev, "failed to request edge wakeup.\n");
goto err_qos;
}
}
sport->port.membase = ioremap(mmres->start, resource_size(mmres));
if (!sport->port.membase) {
ret = -ENOMEM;
goto err_map;
}
INIT_WORK(&sport->uart_tx_lpm_work, uart_tx_lpm_handler);
timer_setup(&sport->pxa_timer, pxa_timer_handler, 0);
serial_pxa_ports[sport->port.line] = sport;
uart_add_one_port(&serial_pxa_reg, &sport->port);
platform_set_drvdata(dev, sport);
/*
* Allocate the IRQ in probe, otherwise if move suspend/resume to
* noirq stage will cause a unbalance irq enable warning.
*/
ret = request_irq(sport->port.irq, serial_pxa_irq, 0, sport->name, sport);
if (ret)
goto err_map;
disable_irq(sport->port.irq);
return 0;
err_map:
if (sport->edge_wakeup_gpio >= 0)
remove_mfp_edge_wakeup(sport->edge_wakeup_gpio);
uart_remove_one_port(&serial_pxa_reg, &sport->port);
iounmap(sport->port.membase);
err_qos:
kfree(sport->qos_idle[PXA_UART_TX].name);
kfree(sport->qos_idle[PXA_UART_RX].name);
pm_qos_remove_request(&sport->qos_idle[PXA_UART_RX]);
pm_qos_remove_request(&sport->qos_idle[PXA_UART_TX]);
err_clk:
clk_unprepare(sport->clk);
clk_put(sport->clk);
err_free:
kfree(sport);
return ret;
}
static int serial_pxa_remove(struct platform_device *dev)
{
struct uart_pxa_port *sport = platform_get_drvdata(dev);
kfree(sport->qos_idle[PXA_UART_TX].name);
kfree(sport->qos_idle[PXA_UART_RX].name);
pm_qos_remove_request(&sport->qos_idle[PXA_UART_RX]);
pm_qos_remove_request(&sport->qos_idle[PXA_UART_TX]);
if (sport->edge_wakeup_gpio >= 0)
remove_mfp_edge_wakeup(sport->edge_wakeup_gpio);
platform_set_drvdata(dev, NULL);
uart_remove_one_port(&serial_pxa_reg, &sport->port);
free_irq(sport->port.irq, sport);
clk_unprepare(sport->clk);
clk_put(sport->clk);
kfree(sport);
serial_pxa_ports[dev->id] = NULL;
return 0;
}
static struct platform_driver serial_pxa_driver = {
.probe = serial_pxa_probe,
.remove = serial_pxa_remove,
.driver = {
.name = "pxa2xx-uart",
.owner = THIS_MODULE,
#ifdef CONFIG_PM
.pm = &serial_pxa_pm_ops,
#endif
.suppress_bind_attrs = true,
.of_match_table = serial_pxa_dt_ids,
},
};
/* 8250 driver for PXA serial ports should be used */
static int __init serial_pxa_init(void)
{
int ret;
ret = uart_register_driver(&serial_pxa_reg);
if (ret != 0)
return ret;
ret = platform_driver_register(&serial_pxa_driver);
if (ret != 0)
uart_unregister_driver(&serial_pxa_reg);
return ret;
}
device_initcall(serial_pxa_init);