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

From: Cameron Gutman
Date: Mon Feb 06 2017 - 17:57:17 EST


On 02/06/2017 02:05 PM, Dmitry Torokhov wrote:
> 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.
>

Ah, so it seems we're missing the LED_CORE_SUSPENDRESUME flag on our LED
device required for that to happen automatically. I'll just use that
instead of manually setting brightness on resume.