2014-09-02 13:40 GMT+02:00 Peter Hurley [off-list ref]:

On 09/01/2014 05:26 AM, Richard Genoud wrote:

quoted

2014-08-10 21:33 GMT+02:00 Peter Hurley [off-list ref]:

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Hi Richard,

Hi !
Sorry for the delay !

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On 05/13/2014 02:20 PM, Richard Genoud wrote:

quoted

Handle CTS/DSR/RI/DCD GPIO interrupts in atmel_serial.

Signed-off-by: Richard Genoud <redacted>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Nicolas Ferre <redacted>
---
 drivers/tty/serial/atmel_serial.c |  125 ++++++++++++++++++++++++++++++++++++-
 1 file changed, 122 insertions(+), 3 deletions(-)

diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index 43ca659..3fceae0 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c

@@ -45,6 +45,7 @@
 #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>

@@ -167,7 +168,9 @@ struct atmel_uart_port {

      struct serial_rs485     rs485;          /* rs485 settings */
      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);

@@ -489,8 +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;

Where are these gpio irqs disabled if !UART_ENABLE_MS()?

They are disabled in atmel_shutdown()/atmel_free_gpio_irq().
Like the doc says in Documentation/serial/driver
  enable_ms(port)
    Enable the modem status interrupts.

    This method may be called multiple times.  Modem status
    interrupts should be disabled when the shutdown method is
    called.

Thanks for replying.

The point of the UART_ENABLE_MS() macro is to allow the UART driver
to determine if modem status interrupts need to be enabled when
handling the .set_termios() method.

When handling set_termios(), if UART_ENABLE_MS is false (ie., the
serial core does not require modem status interrupts), the UART
driver can and should turn modem status interrupts off.

It is _also_ true that "modem status interrupts should be disabled
when the shutdown method is called"; in fact, _all_ UART-sourced
interrupts should be disabled when the shutdown method is called.

That's right. I totally missed that !
I'll come with a patch.

Thanks !!

Richard.