On Fri, 26 Jul 2024 14:57:03 -0700 Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> wrote: > On Fri, Jul 26, 2024 at 02:57:03PM -0700, Dmitry Torokhov wrote: > > Hi Qiang, > > > > On Fri, Jul 26, 2024 at 06:27:30PM +0800, Qiang Ma wrote: > > > After we turn on the keyboard CAPSL LED and let the system > > > suspend, the keyboard LED is not off, and the kernel log is as > > > follows: > > > > > > [ 185.987574] i8042: [44060] ed -> i8042 (kbd-data) > > > [ 185.988057] i8042: [44061] ** <- i8042 (interrupt, 0, 1) > > > [ 185.988067] i8042: [44061] 04 -> i8042 (kbd-data) > > > [ 185.988248] i8042: [44061] ** <- i8042 (interrupt, 0, 1) > > > > > > The log shows that after the command 0xed is sent, the data > > > sent is 0x04 instead of 0x00. > > > > > > Solution: > > > Add a bitmap variable ledon in the atkbd structure, and then set > > > ledon according to code-value in the event, in the atkbd_set_leds > > > function, first look at the value of lenon, if it is 0, there is > > > no need to look at the value of dev->led, otherwise, Need to look > > > at dev->led to determine the keyboard LED on/off. > > > > I am not sure why duplicating input_dev->led which is supposed to > > record which LEDs are currently active on an input device would > > solve the issue. Could you please explain? > > Ah, OK, I see it now. We do not actually toggle input_dev->led when > suspending, so atkbd uses wrong data to determine the LED state. > Yes, that's true. > > > > The input core is supposed to turn off all LEDs on suspend. This > > happens in input_dev_toggle() which is called from > > input_dev_suspend(). It iterates over all LEDs on a device and > > turns off active ones one by one. > > > > I think what happens here is we are running afoul of the throttling > > done in atkbd (see atkbd_schedule_event_work), and it does not > > actually turn off all LEDs in time. But on the other hand > > atkbd_cleanup() (which is called to suspend the keyboard) calls > > > > ps2_command(&atkbd->ps2dev, NULL, ATKBD_CMD_RESET_DEF); > > > > which should turn off everything anyways. > > But still, why ATKBD_CMD_RESET_DEF does not shut off the LEDs for you? > Looking at a ps/2 keyboard document(http://www-ug.eecg.toronto.edu/msl/nios_devices/datasheets/PS2%20Keyboard%20Protocol.htm), the F6 command does not seem to affect the state of the LED. > Thanks. > > -- > Dmitry -- Qiang
