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path: root/drivers/tty/serial/atmel_serial.c
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Diffstat (limited to 'drivers/tty/serial/atmel_serial.c')
-rw-r--r--drivers/tty/serial/atmel_serial.c230
1 files changed, 192 insertions, 38 deletions
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index 53eeea13ff16..3fceae099c44 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -43,6 +43,9 @@
#include <linux/platform_data/atmel.h>
#include <linux/timer.h>
#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
+#include <linux/err.h>
+#include <linux/irq.h>
#include <asm/io.h>
#include <asm/ioctls.h>
@@ -57,6 +60,8 @@
#include <linux/serial_core.h>
+#include "serial_mctrl_gpio.h"
+
static void atmel_start_rx(struct uart_port *port);
static void atmel_stop_rx(struct uart_port *port);
@@ -162,8 +167,10 @@ struct atmel_uart_port {
struct circ_buf rx_ring;
struct serial_rs485 rs485; /* rs485 settings */
- int rts_gpio; /* optional RTS GPIO */
+ struct mctrl_gpios *gpios;
+ int gpio_irq[UART_GPIO_MAX];
unsigned int tx_done_mask;
+ bool ms_irq_enabled;
bool is_usart; /* usart or uart */
struct timer_list uart_timer; /* uart timer */
int (*prepare_rx)(struct uart_port *port);
@@ -237,6 +244,50 @@ static bool atmel_use_dma_rx(struct uart_port *port)
return atmel_port->use_dma_rx;
}
+static unsigned int atmel_get_lines_status(struct uart_port *port)
+{
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+ unsigned int status, ret = 0;
+
+ status = UART_GET_CSR(port);
+
+ mctrl_gpio_get(atmel_port->gpios, &ret);
+
+ if (!IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(atmel_port->gpios,
+ UART_GPIO_CTS))) {
+ if (ret & TIOCM_CTS)
+ status &= ~ATMEL_US_CTS;
+ else
+ status |= ATMEL_US_CTS;
+ }
+
+ if (!IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(atmel_port->gpios,
+ UART_GPIO_DSR))) {
+ if (ret & TIOCM_DSR)
+ status &= ~ATMEL_US_DSR;
+ else
+ status |= ATMEL_US_DSR;
+ }
+
+ if (!IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(atmel_port->gpios,
+ UART_GPIO_RI))) {
+ if (ret & TIOCM_RI)
+ status &= ~ATMEL_US_RI;
+ else
+ status |= ATMEL_US_RI;
+ }
+
+ if (!IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(atmel_port->gpios,
+ UART_GPIO_DCD))) {
+ if (ret & TIOCM_CD)
+ status &= ~ATMEL_US_DCD;
+ else
+ status |= ATMEL_US_DCD;
+ }
+
+ return status;
+}
+
/* Enable or disable the rs485 support */
void atmel_config_rs485(struct uart_port *port, struct serial_rs485 *rs485conf)
{
@@ -296,17 +347,6 @@ static void atmel_set_mctrl(struct uart_port *port, u_int mctrl)
unsigned int mode;
struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
- /*
- * AT91RM9200 Errata #39: RTS0 is not internally connected
- * to PA21. We need to drive the pin as a GPIO.
- */
- if (gpio_is_valid(atmel_port->rts_gpio)) {
- if (mctrl & TIOCM_RTS)
- gpio_set_value(atmel_port->rts_gpio, 0);
- else
- gpio_set_value(atmel_port->rts_gpio, 1);
- }
-
if (mctrl & TIOCM_RTS)
control |= ATMEL_US_RTSEN;
else
@@ -319,6 +359,8 @@ static void atmel_set_mctrl(struct uart_port *port, u_int mctrl)
UART_PUT_CR(port, control);
+ mctrl_gpio_set(atmel_port->gpios, mctrl);
+
/* Local loopback mode? */
mode = UART_GET_MR(port) & ~ATMEL_US_CHMODE;
if (mctrl & TIOCM_LOOP)
@@ -346,7 +388,8 @@ static void atmel_set_mctrl(struct uart_port *port, u_int mctrl)
*/
static u_int atmel_get_mctrl(struct uart_port *port)
{
- unsigned int status, ret = 0;
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+ unsigned int ret = 0, status;
status = UART_GET_CSR(port);
@@ -362,7 +405,7 @@ static u_int atmel_get_mctrl(struct uart_port *port)
if (!(status & ATMEL_US_RI))
ret |= TIOCM_RI;
- return ret;
+ return mctrl_gpio_get(atmel_port->gpios, &ret);
}
/*
@@ -449,8 +492,38 @@ static void atmel_stop_rx(struct uart_port *port)
*/
static void atmel_enable_ms(struct uart_port *port)
{
- UART_PUT_IER(port, ATMEL_US_RIIC | ATMEL_US_DSRIC
- | ATMEL_US_DCDIC | ATMEL_US_CTSIC);
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+ uint32_t ier = 0;
+
+ /*
+ * Interrupt should not be enabled twice
+ */
+ if (atmel_port->ms_irq_enabled)
+ return;
+
+ atmel_port->ms_irq_enabled = true;
+
+ if (atmel_port->gpio_irq[UART_GPIO_CTS] >= 0)
+ enable_irq(atmel_port->gpio_irq[UART_GPIO_CTS]);
+ else
+ ier |= ATMEL_US_CTSIC;
+
+ if (atmel_port->gpio_irq[UART_GPIO_DSR] >= 0)
+ enable_irq(atmel_port->gpio_irq[UART_GPIO_DSR]);
+ else
+ ier |= ATMEL_US_DSRIC;
+
+ if (atmel_port->gpio_irq[UART_GPIO_RI] >= 0)
+ enable_irq(atmel_port->gpio_irq[UART_GPIO_RI]);
+ else
+ ier |= ATMEL_US_RIIC;
+
+ if (atmel_port->gpio_irq[UART_GPIO_DCD] >= 0)
+ enable_irq(atmel_port->gpio_irq[UART_GPIO_DCD]);
+ else
+ ier |= ATMEL_US_DCDIC;
+
+ UART_PUT_IER(port, ier);
}
/*
@@ -1039,11 +1112,31 @@ atmel_handle_status(struct uart_port *port, unsigned int pending,
static irqreturn_t atmel_interrupt(int irq, void *dev_id)
{
struct uart_port *port = dev_id;
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
unsigned int status, pending, pass_counter = 0;
+ bool gpio_handled = false;
do {
- status = UART_GET_CSR(port);
+ status = atmel_get_lines_status(port);
pending = status & UART_GET_IMR(port);
+ if (!gpio_handled) {
+ /*
+ * Dealing with GPIO interrupt
+ */
+ if (irq == atmel_port->gpio_irq[UART_GPIO_CTS])
+ pending |= ATMEL_US_CTSIC;
+
+ if (irq == atmel_port->gpio_irq[UART_GPIO_DSR])
+ pending |= ATMEL_US_DSRIC;
+
+ if (irq == atmel_port->gpio_irq[UART_GPIO_RI])
+ pending |= ATMEL_US_RIIC;
+
+ if (irq == atmel_port->gpio_irq[UART_GPIO_DCD])
+ pending |= ATMEL_US_DCDIC;
+
+ gpio_handled = true;
+ }
if (!pending)
break;
@@ -1523,6 +1616,45 @@ static void atmel_get_ip_name(struct uart_port *port)
}
}
+static void atmel_free_gpio_irq(struct uart_port *port)
+{
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+ enum mctrl_gpio_idx i;
+
+ for (i = 0; i < UART_GPIO_MAX; i++)
+ if (atmel_port->gpio_irq[i] >= 0)
+ free_irq(atmel_port->gpio_irq[i], port);
+}
+
+static int atmel_request_gpio_irq(struct uart_port *port)
+{
+ struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+ int *irq = atmel_port->gpio_irq;
+ enum mctrl_gpio_idx i;
+ int err = 0;
+
+ for (i = 0; (i < UART_GPIO_MAX) && !err; i++) {
+ if (irq[i] < 0)
+ continue;
+
+ irq_set_status_flags(irq[i], IRQ_NOAUTOEN);
+ err = request_irq(irq[i], atmel_interrupt, IRQ_TYPE_EDGE_BOTH,
+ "atmel_serial", port);
+ if (err)
+ dev_err(port->dev, "atmel_startup - Can't get %d irq\n",
+ irq[i]);
+ }
+
+ /*
+ * If something went wrong, rollback.
+ */
+ while (err && (--i >= 0))
+ if (irq[i] >= 0)
+ free_irq(irq[i], port);
+
+ return err;
+}
+
/*
* Perform initialization and enable port for reception
*/
@@ -1539,6 +1671,7 @@ static int atmel_startup(struct uart_port *port)
* handle an unexpected interrupt
*/
UART_PUT_IDR(port, -1);
+ atmel_port->ms_irq_enabled = false;
/*
* Allocate the IRQ
@@ -1551,6 +1684,13 @@ static int atmel_startup(struct uart_port *port)
}
/*
+ * Get the GPIO lines IRQ
+ */
+ retval = atmel_request_gpio_irq(port);
+ if (retval)
+ goto free_irq;
+
+ /*
* Initialize DMA (if necessary)
*/
atmel_init_property(atmel_port, pdev);
@@ -1568,7 +1708,7 @@ static int atmel_startup(struct uart_port *port)
}
/* Save current CSR for comparison in atmel_tasklet_func() */
- atmel_port->irq_status_prev = UART_GET_CSR(port);
+ atmel_port->irq_status_prev = atmel_get_lines_status(port);
atmel_port->irq_status = atmel_port->irq_status_prev;
/*
@@ -1614,6 +1754,11 @@ static int atmel_startup(struct uart_port *port)
}
return 0;
+
+free_irq:
+ free_irq(port->irq, port);
+
+ return retval;
}
/*
@@ -1661,9 +1806,12 @@ static void atmel_shutdown(struct uart_port *port)
atmel_port->rx_ring.tail = 0;
/*
- * Free the interrupt
+ * Free the interrupts
*/
free_irq(port->irq, port);
+ atmel_free_gpio_irq(port);
+
+ atmel_port->ms_irq_enabled = false;
}
/*
@@ -2324,6 +2472,26 @@ static int atmel_serial_resume(struct platform_device *pdev)
#define atmel_serial_resume NULL
#endif
+static int atmel_init_gpios(struct atmel_uart_port *p, struct device *dev)
+{
+ enum mctrl_gpio_idx i;
+ struct gpio_desc *gpiod;
+
+ p->gpios = mctrl_gpio_init(dev, 0);
+ if (IS_ERR_OR_NULL(p->gpios))
+ return -1;
+
+ for (i = 0; i < UART_GPIO_MAX; i++) {
+ gpiod = mctrl_gpio_to_gpiod(p->gpios, i);
+ if (gpiod && (gpiod_get_direction(gpiod) == GPIOF_DIR_IN))
+ p->gpio_irq[i] = gpiod_to_irq(gpiod);
+ else
+ p->gpio_irq[i] = -EINVAL;
+ }
+
+ return 0;
+}
+
static int atmel_serial_probe(struct platform_device *pdev)
{
struct atmel_uart_port *port;
@@ -2359,25 +2527,11 @@ static int atmel_serial_probe(struct platform_device *pdev)
port = &atmel_ports[ret];
port->backup_imr = 0;
port->uart.line = ret;
- port->rts_gpio = -EINVAL; /* Invalid, zero could be valid */
- if (pdata)
- port->rts_gpio = pdata->rts_gpio;
- else if (np)
- port->rts_gpio = of_get_named_gpio(np, "rts-gpios", 0);
-
- if (gpio_is_valid(port->rts_gpio)) {
- ret = devm_gpio_request(&pdev->dev, port->rts_gpio, "RTS");
- if (ret) {
- dev_err(&pdev->dev, "error requesting RTS GPIO\n");
- goto err;
- }
- /* Default to 1 as RTS is active low */
- ret = gpio_direction_output(port->rts_gpio, 1);
- if (ret) {
- dev_err(&pdev->dev, "error setting up RTS GPIO\n");
- goto err;
- }
- }
+
+ ret = atmel_init_gpios(port, &pdev->dev);
+ if (ret < 0)
+ dev_err(&pdev->dev, "%s",
+ "Failed to initialize GPIOs. The serial port may not work as expected");
ret = atmel_init_port(port, pdev);
if (ret)