On 08/19/2016 06:36 PM, Johan Fjeldtvedt wrote:
> Make sending messages to the adapter serialized within the driver.
> 
> send_and_wait is split into send_and_wait_once, which only sends once
> and checks for the result, and the higher level send_and_wait, which
> performs locking and retries.
> 
> Signed-off-by: Johan Fjeldtvedt <jaf...@gmail.com>
> ---
>  drivers/staging/media/pulse8-cec/pulse8-cec.c | 50 
> ++++++++++++++++-----------
>  1 file changed, 30 insertions(+), 20 deletions(-)
> 
> diff --git a/drivers/staging/media/pulse8-cec/pulse8-cec.c 
> b/drivers/staging/media/pulse8-cec/pulse8-cec.c
> index ed8bd95..fdb2407 100644
> --- a/drivers/staging/media/pulse8-cec/pulse8-cec.c
> +++ b/drivers/staging/media/pulse8-cec/pulse8-cec.c
> @@ -99,6 +99,7 @@ struct pulse8 {
>       unsigned int idx;
>       bool escape;
>       bool started;
> +     struct mutex write_lock;
>  };
>  
>  static void pulse8_irq_work_handler(struct work_struct *work)
> @@ -233,8 +234,8 @@ static int pulse8_send(struct serio *serio, const u8 
> *command, u8 cmd_len)
>       return err;
>  }
>  
> -static int pulse8_send_and_wait(struct pulse8 *pulse8,
> -                             const u8 *cmd, u8 cmd_len, u8 response, u8 size)
> +static int pulse8_send_and_wait_once(struct pulse8 *pulse8,
> +                                  const u8 *cmd, u8 cmd_len, u8 response, u8 
> size)
>  {
>       int err;
>  
> @@ -250,24 +251,8 @@ static int pulse8_send_and_wait(struct pulse8 *pulse8,
>       if ((pulse8->data[0] & 0x3f) == MSGCODE_COMMAND_REJECTED &&
>           cmd[0] != MSGCODE_SET_CONTROLLED &&
>           cmd[0] != MSGCODE_SET_AUTO_ENABLED &&
> -         cmd[0] != MSGCODE_GET_BUILDDATE) {
> -             u8 cmd_sc[2];
> -
> -             cmd_sc[0] = MSGCODE_SET_CONTROLLED;
> -             cmd_sc[1] = 1;
> -             err = pulse8_send_and_wait(pulse8, cmd_sc, 2,
> -                                        MSGCODE_COMMAND_ACCEPTED, 1);
> -             if (err)
> -                     return err;
> -             init_completion(&pulse8->cmd_done);
> -
> -             err = pulse8_send(pulse8->serio, cmd, cmd_len);
> -             if (err)
> -                     return err;
> -
> -             if (!wait_for_completion_timeout(&pulse8->cmd_done, HZ))
> -                     return -ETIMEDOUT;
> -     }
> +         cmd[0] != MSGCODE_GET_BUILDDATE)
> +             return -ENOTTY;
>       if (response &&
>           ((pulse8->data[0] & 0x3f) != response || pulse8->len < size + 1)) {
>               dev_info(pulse8->dev, "transmit: failed %02x\n",
> @@ -277,6 +262,30 @@ static int pulse8_send_and_wait(struct pulse8 *pulse8,
>       return 0;
>  }
>  
> +static int pulse8_send_and_wait(struct pulse8 *pulse8,
> +                             const u8 *cmd, u8 cmd_len, u8 response, u8 size)
> +{
> +     u8 cmd_sc[2];
> +     int err;
> +
> +     mutex_lock(&pulse8->write_lock);
> +     err = pulse8_send_and_wait_once(pulse8, cmd, cmd_len, response, size);
> +
> +     if (err == -ENOTTY) {
> +             cmd_sc[0] = MSGCODE_SET_CONTROLLED;
> +             cmd_sc[1] = 1;
> +             err = pulse8_send_and_wait_once(pulse8, cmd_sc, 2,
> +                                             MSGCODE_COMMAND_ACCEPTED, 1);
> +             if (err)
> +                     goto unlock;
> +             err = pulse8_send_and_wait_once(pulse8, cmd, cmd_len, response, 
> size);
> +     }
> +
> +  unlock:
> +     mutex_unlock(&pulse8->write_lock);
> +     return err;

This should be:

        return err == -ENOTTY ? -EIO : err;

We don't want the ENOTTY to end up in userspace.

Regards,

        Hans

> +}
> +
>  static int pulse8_setup(struct pulse8 *pulse8, struct serio *serio)
>  {
>       u8 *data = pulse8->data + 1;
> @@ -453,6 +462,7 @@ static int pulse8_connect(struct serio *serio, struct 
> serio_driver *drv)
>       pulse8->dev = &serio->dev;
>       serio_set_drvdata(serio, pulse8);
>       INIT_WORK(&pulse8->work, pulse8_irq_work_handler);
> +     mutex_init(&pulse8->write_lock);
>  
>       err = serio_open(serio, drv);
>       if (err)
> 
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to