Re: [PATCH 4/5] Input: xpad - restore LED state after device resume

From: Dmitry Torokhov
Date: Mon Feb 06 2017 - 17:05:25 EST


On Sat, Feb 04, 2017 at 04:30:01PM -0800, Cameron Gutman wrote:
> The state of pad LEDs can be inconsistent when the system is
> woken up after sleep. Rather than leaving the controllers blinking,
> let's resend the last LED command to Xbox 360 pads on resume.
>
> Since Xbox One pads stop flashing only when reinitialized, we'll
> send them the initialization packet so they calm down too.
>
> Signed-off-by: Cameron Gutman <aicommander@xxxxxxxxx>
> ---
> drivers/input/joystick/xpad.c | 14 +++++++++++++-
> 1 file changed, 13 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/input/joystick/xpad.c b/drivers/input/joystick/xpad.c
> index 13f298d..1179266 100644
> --- a/drivers/input/joystick/xpad.c
> +++ b/drivers/input/joystick/xpad.c
> @@ -1683,11 +1683,23 @@ static int xpad_resume(struct usb_interface *intf)
> retval = xpad360w_start_input(xpad);
> } else {
> mutex_lock(&input->mutex);
> - if (input->users)
> + if (input->users) {
> retval = xpad_start_input(xpad);
> + } else if (xpad->xtype == XTYPE_XBOXONE) {
> + /*
> + * Even if there are no users, we'll send Xbox One pads
> + * the startup sequence so they don't sit there and
> + * blink until somebody opens the input device again.
> + */
> + retval = xpad_start_xbox_one(xpad);
> + }
> mutex_unlock(&input->mutex);
> }
>
> + /* LED state is lost across resume, so resend the last command */
> + if (xpad->led)
> + xpad_send_led_command(xpad, xpad->led->led_cdev.brightness);

I can see that we might need to send the "start" command, but I am not
sure that explicitly calling xpad_send_led_command() is needed: LED core
should restore LED state upon resume, and this should happen after its
parent (i.e. xbox device) is resumed.

Thanks.

--
Dmitry