Re: [PATCH v2] input: don't call input_dev_release_keys() in resume

[Oskar Andero <oskar.andero@sonymobile.com>]

Hi Dmitry,

On 03:14 Tue 26 Nov     , Dmitry Torokhov wrote:
> Hi Oskar,
> 
> On Fri, Nov 22, 2013 at 02:27:04PM +0100, Oskar Andero wrote:
> > From: Aleksej Makarov <aleksej.makarov@sonymobile.com>
> > 
> > When waking up the platform by pressing a specific key, sending a
> > release on that key makes it impossible to react on the event in
> > user-space. This is fixed by moving the input_reset_device() call to
> > resume instead.
> > 
> > Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> > Reviewed-by: Radovan Lekanovic <radovan.lekanovic@sonymobile.com>
> > Signed-off-by: Aleksej Makarov <aleksej.makarov@sonymobile.com>
> > Signed-off-by: Oskar Andero <oskar.andero@sonymobile.com>
> > ---
> >  drivers/input/input.c | 11 +----------
> >  1 file changed, 1 insertion(+), 10 deletions(-)
> > 
> > diff --git a/drivers/input/input.c b/drivers/input/input.c
> > index 846ccdd..511d490 100644
> > --- a/drivers/input/input.c
> > +++ b/drivers/input/input.c
> > @@ -1676,22 +1676,13 @@ static int input_dev_suspend(struct device *dev)
> >  {
> >  	struct input_dev *input_dev = to_input_dev(dev);
> >  
> > -	mutex_lock(&input_dev->mutex);
> > -
> > -	if (input_dev->users)
> > -		input_dev_toggle(input_dev, false);
> > -
> > -	mutex_unlock(&input_dev->mutex);
> > +	input_reset_device(input_dev);
> >  
> >  	return 0;
> >  }
> >  
> >  static int input_dev_resume(struct device *dev)
> >  {
> > -	struct input_dev *input_dev = to_input_dev(dev);
> > -
> > -	input_reset_device(input_dev);
> 
> We still need to restore LED state after resume. Does the patch below
> work for you?

Finally found some time to test the patch! Not much left of the initial
one though. :)

The patch works for our use-case, i.e. wake-up the phone by pressing a
key and then be able to retrieve what key was pressed.
Please note that I haven't tested the LED/sound and hibernation parts
of the patch.

Thanks,
 Oskar

> 
> Input: don't call input_dev_release_keys() in resume
> 
> From: Aleksej Makarov <aleksej.makarov@sonymobile.com>
> 
> When waking up the platform by pressing a specific key, sending a
> release on that key makes it impossible to react on the event in
> user-space. This is fixed by moving the input_reset_device() call to
> resume instead.
> 
> [dmitry.torokhov@gmail.com: make sure we still restore LED/sound state
> after resume, handle hibernation properly]
> 
> Signed-off-by: Aleksej Makarov <aleksej.makarov@sonymobile.com>
> Signed-off-by: Oskar Andero <oskar.andero@sonymobile.com>
> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> ---
>  drivers/input/input.c |   76 +++++++++++++++++++++++++++++++++++++------------
>  1 file changed, 57 insertions(+), 19 deletions(-)
> 
> diff --git a/drivers/input/input.c b/drivers/input/input.c
> index 846ccdd..692435a 100644
> --- a/drivers/input/input.c
> +++ b/drivers/input/input.c
> @@ -1653,35 +1653,36 @@ static void input_dev_toggle(struct input_dev *dev, bool activate)
>   */
>  void input_reset_device(struct input_dev *dev)
>  {
> -	mutex_lock(&dev->mutex);
> +	unsigned long flags;
>  
> -	if (dev->users) {
> -		input_dev_toggle(dev, true);
> +	mutex_lock(&dev->mutex);
> +	spin_lock_irqsave(&dev->event_lock, flags);
>  
> -		/*
> -		 * Keys that have been pressed at suspend time are unlikely
> -		 * to be still pressed when we resume.
> -		 */
> -		spin_lock_irq(&dev->event_lock);
> -		input_dev_release_keys(dev);
> -		spin_unlock_irq(&dev->event_lock);
> -	}
> +	input_dev_toggle(dev, true);
> +	input_dev_release_keys(dev);
>  
> +	spin_unlock_irqrestore(&dev->event_lock, flags);
>  	mutex_unlock(&dev->mutex);
>  }
>  EXPORT_SYMBOL(input_reset_device);
>  
> -#ifdef CONFIG_PM
> +#ifdef CONFIG_PM_SLEEP
>  static int input_dev_suspend(struct device *dev)
>  {
>  	struct input_dev *input_dev = to_input_dev(dev);
>  
> -	mutex_lock(&input_dev->mutex);
> +	spin_lock_irq(&input_dev->event_lock);
>  
> -	if (input_dev->users)
> -		input_dev_toggle(input_dev, false);
> +	/*
> +	 * Keys that are pressed now are unlikely to be
> +	 * still pressed when we resume.
> +	 */
> +	input_dev_release_keys(input_dev);
>  
> -	mutex_unlock(&input_dev->mutex);
> +	/* Turn off LEDs and sounds, if any are active. */
> +	input_dev_toggle(input_dev, false);
> +
> +	spin_unlock_irq(&input_dev->event_lock);
>  
>  	return 0;
>  }
> @@ -1690,7 +1691,43 @@ static int input_dev_resume(struct device *dev)
>  {
>  	struct input_dev *input_dev = to_input_dev(dev);
>  
> -	input_reset_device(input_dev);
> +	spin_lock_irq(&input_dev->event_lock);
> +
> +	/* Restore state of LEDs and sounds, if any were active. */
> +	input_dev_toggle(input_dev, true);
> +
> +	spin_unlock_irq(&input_dev->event_lock);
> +
> +	return 0;
> +}
> +
> +static int input_dev_freeze(struct device *dev)
> +{
> +	struct input_dev *input_dev = to_input_dev(dev);
> +
> +	spin_lock_irq(&input_dev->event_lock);
> +
> +	/*
> +	 * Keys that are pressed now are unlikely to be
> +	 * still pressed when we resume.
> +	 */
> +	input_dev_release_keys(input_dev);
> +
> +	spin_unlock_irq(&input_dev->event_lock);
> +
> +	return 0;
> +}
> +
> +static int input_dev_poweroff(struct device *dev)
> +{
> +	struct input_dev *input_dev = to_input_dev(dev);
> +
> +	spin_lock_irq(&input_dev->event_lock);
> +
> +	/* Turn off LEDs and sounds, if any are active. */
> +	input_dev_toggle(input_dev, false);
> +
> +	spin_unlock_irq(&input_dev->event_lock);
>  
>  	return 0;
>  }
> @@ -1698,7 +1735,8 @@ static int input_dev_resume(struct device *dev)
>  static const struct dev_pm_ops input_dev_pm_ops = {
>  	.suspend	= input_dev_suspend,
>  	.resume		= input_dev_resume,
> -	.poweroff	= input_dev_suspend,
> +	.freeze		= input_dev_freeze,
> +	.poweroff	= input_dev_poweroff,
>  	.restore	= input_dev_resume,
>  };
>  #endif /* CONFIG_PM */
> @@ -1707,7 +1745,7 @@ static struct device_type input_dev_type = {
>  	.groups		= input_dev_attr_groups,
>  	.release	= input_dev_release,
>  	.uevent		= input_dev_uevent,
> -#ifdef CONFIG_PM
> +#ifdef CONFIG_PM_SLEEP
>  	.pm		= &input_dev_pm_ops,
>  #endif
>  };