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path: root/drivers/tty/serial/omap-serial.c
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Diffstat (limited to 'drivers/tty/serial/omap-serial.c')
-rw-r--r--drivers/tty/serial/omap-serial.c141
1 files changed, 97 insertions, 44 deletions
diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index 816d1a23f9d0..fa511ebab67c 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -39,6 +39,7 @@
#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>
@@ -134,6 +135,7 @@ 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;
@@ -175,7 +177,7 @@ struct uart_omap_port {
bool is_suspending;
};
-#define to_uart_omap_port(p) ((container_of((p), struct uart_omap_port, port)))
+#define to_uart_omap_port(p) ((container_of((p), struct uart_omap_port, port)))
static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
@@ -214,10 +216,23 @@ static int serial_omap_get_context_loss_count(struct uart_omap_port *up)
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(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);
+ serial_omap_enable_wakeirq(up, enable);
if (!pdata || !pdata->enable_wakeup)
return;
@@ -242,12 +257,12 @@ serial_omap_baud_is_mode16(struct uart_port *port, unsigned int baud)
unsigned int n16 = port->uartclk / (16 * baud);
int baudAbsDiff13 = baud - (port->uartclk / (13 * n13));
int baudAbsDiff16 = baud - (port->uartclk / (16 * n16));
- if(baudAbsDiff13 < 0)
+ if (baudAbsDiff13 < 0)
baudAbsDiff13 = -baudAbsDiff13;
- if(baudAbsDiff16 < 0)
+ if (baudAbsDiff16 < 0)
baudAbsDiff16 = -baudAbsDiff16;
- return (baudAbsDiff13 > baudAbsDiff16);
+ return (baudAbsDiff13 >= baudAbsDiff16);
}
/*
@@ -258,13 +273,13 @@ serial_omap_baud_is_mode16(struct uart_port *port, unsigned int baud)
static unsigned int
serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
{
- unsigned int divisor;
+ unsigned int mode;
if (!serial_omap_baud_is_mode16(port, baud))
- divisor = 13;
+ mode = 13;
else
- divisor = 16;
- return port->uartclk/(baud * divisor);
+ mode = 16;
+ return port->uartclk/(mode * baud);
}
static void serial_omap_enable_ms(struct uart_port *port)
@@ -283,28 +298,40 @@ static void serial_omap_enable_ms(struct uart_port *port)
static void serial_omap_stop_tx(struct uart_port *port)
{
struct uart_omap_port *up = to_uart_omap_port(port);
- struct circ_buf *xmit = &up->port.state->xmit;
int res;
pm_runtime_get_sync(up->dev);
- /* handle rs485 */
+ /* Handle RS-485 */
if (up->rs485.flags & SER_RS485_ENABLED) {
- /* do nothing if current tx not yet completed */
- res = serial_in(up, UART_LSR) & UART_LSR_TEMT;
- if (!res)
- return;
-
- /* if there's no more data to send, turn off rts */
- if (uart_circ_empty(xmit)) {
- /* if rts not already disabled */
+ 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) {
+ 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;
}
}
@@ -384,15 +411,18 @@ static void serial_omap_start_tx(struct uart_port *port)
pm_runtime_get_sync(up->dev);
- /* handle rs485 */
+ /* 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) {
+ if (up->rs485.delay_rts_before_send > 0)
mdelay(up->rs485.delay_rts_before_send);
- }
}
}
@@ -699,6 +729,20 @@ static int serial_omap_startup(struct uart_port *port)
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);
+ } else {
+ dev_info(up->port.dev, "no wakeirq for uart%d\n",
+ up->port.line);
+ }
+
dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->port.line);
pm_runtime_get_sync(up->dev);
@@ -787,6 +831,8 @@ static void serial_omap_shutdown(struct uart_port *port)
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)
@@ -938,7 +984,7 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
*/
/* Set receive FIFO threshold to 16 characters and
- * transmit FIFO threshold to 16 spaces
+ * transmit FIFO threshold to 32 spaces
*/
up->fcr &= ~OMAP_UART_FCR_RX_FIFO_TRIG_MASK;
up->fcr &= ~OMAP_UART_FCR_TX_FIFO_TRIG_MASK;
@@ -1060,15 +1106,6 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
dev_dbg(up->port.dev, "serial_omap_set_termios+%d\n", up->port.line);
}
-static int serial_omap_set_wake(struct uart_port *port, unsigned int state)
-{
- struct uart_omap_port *up = to_uart_omap_port(port);
-
- serial_omap_enable_wakeup(up, state);
-
- return 0;
-}
-
static void
serial_omap_pm(struct uart_port *port, unsigned int state,
unsigned int oldstate)
@@ -1353,6 +1390,15 @@ serial_omap_config_rs485(struct uart_port *port, struct serial_rs485 *rs485conf)
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);
@@ -1401,7 +1447,6 @@ static struct uart_ops serial_omap_pops = {
.shutdown = serial_omap_shutdown,
.set_termios = serial_omap_set_termios,
.pm = serial_omap_pm,
- .set_wake = serial_omap_set_wake,
.type = serial_omap_type,
.release_port = serial_omap_release_port,
.request_port = serial_omap_request_port,
@@ -1582,11 +1627,23 @@ static int serial_omap_probe(struct platform_device *pdev)
struct uart_omap_port *up;
struct resource *mem, *irq;
struct omap_uart_port_info *omap_up_info = dev_get_platdata(&pdev->dev);
- int ret;
+ int ret, uartirq = 0, wakeirq = 0;
+ /* 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 {
+ irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+ if (!irq) {
+ dev_err(&pdev->dev, "no irq resource?\n");
+ return -ENODEV;
+ }
+ uartirq = irq->start;
}
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -1595,12 +1652,6 @@ static int serial_omap_probe(struct platform_device *pdev)
return -ENODEV;
}
- irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
- if (!irq) {
- dev_err(&pdev->dev, "no irq resource?\n");
- return -ENODEV;
- }
-
if (!devm_request_mem_region(&pdev->dev, mem->start, resource_size(mem),
pdev->dev.driver->name)) {
dev_err(&pdev->dev, "memory region already claimed\n");
@@ -1634,7 +1685,8 @@ static int serial_omap_probe(struct platform_device *pdev)
up->port.dev = &pdev->dev;
up->port.type = PORT_OMAP;
up->port.iotype = UPIO_MEM;
- up->port.irq = irq->start;
+ up->port.irq = uartirq;
+ up->wakeirq = wakeirq;
up->port.regshift = 2;
up->port.fifosize = 64;
@@ -1670,8 +1722,9 @@ static int serial_omap_probe(struct platform_device *pdev)
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);
+ dev_warn(&pdev->dev,
+ "No clock speed specified: using default: %d\n",
+ DEFAULT_CLK_SPEED);
}
up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;