On Wed, Jun 25, 2025 at 03:34:55PM +0000, Limonciello, Mario wrote: > On 6/25/25 10:17 AM, Andy Shevchenko wrote: > > On Wed, Jun 25, 2025 at 03:14:40PM +0000, Limonciello, Mario wrote: > >> On 6/25/25 10:10 AM, Andy Shevchenko wrote: > >>> On Wed, Jun 25, 2025 at 03:02:18PM +0000, Limonciello, Mario wrote: > >>>> On 6/25/25 9:41 AM, Mario Limonciello wrote: > >>>>> On 6/25/25 9:31 AM, Hans de Goede wrote: > >>>>>> On 25-Jun-25 4:09 PM, Mario Limonciello wrote: > >>>>>>> On 6/25/25 4:09 AM, Hans de Goede wrote: > >>>>>>>> On 24-Jun-25 10:22 PM, Mario Limonciello wrote: ... > >>>>>> Ok, so specifically the gpiod_set_debounce() call with 50 ms > >>>>>> done by gpio_keys.c is the problem I guess? > >>>>> > >>>>> Yep. > >>>>> > >>>>>> So amd_gpio_set_debounce() does accept the 50 ms debounce > >>>>>> passed to it by gpio_keys.c as a valid value and then setting > >>>>>> that breaks the wake from suspend? > >>>>> > >>>>> That's right. > >>> > >>>>>>> Also comparing the GPIO register in Windows (where things work) > >>>>>>> Windows never programs a debounce. > >>>>>> > >>>>>> So maybe the windows ACPI0011 driver always uses a software- > >>>>>> debounce for the buttons? Windows not debouncing the mechanical > >>>>>> switches at all seems unlikely. > >>>>>> > >>>>>> I think the best way to fix this might be to add a no-hw-debounce > >>>>>> flag to the data passed from soc_button_array.c to gpio_keys.c > >>>>>> and have gpio_keys.c not call gpiod_set_debounce() when the > >>>>>> no-hw-debounce flag is set. > >>>>>> > >>>>>> I've checked and both on Bay Trail and Cherry Trail devices > >>>>>> where soc_button_array is used a lot hw-debouncing is already > >>>>>> unused. pinctrl-baytrail.c does not accept 50 ms as a valid > >>>>>> value and pinctrl-cherryview.c does not support hw debounce > >>>>>> at all. > >>>>> > >>>>> That sounds a like a generally good direction to me. > >>> > >>> Thinking a bit more of this, perhaps the HW debounce support flag should be > >>> per-GPIO-descriptor thingy. In such cases we don't need to distinguish the > >>> platforms, the GPIO ACPI lib may simply set that flag based on 0 read from > >>> the ACPI tables. It will also give a clue to any driver that uses GPIOs > >>> (not only gpio-keys). > >> > >> But 0 doesn't mean hardware debounce support is there, 0 means that > >> hardware debounce is not required to be programmed for this GPIO. > >> > >> That is - if another system had a non-zero value in the GpioInt entry I > >> would expect this to be translated into the GPIO register. > > > > Correct. The question is only about 0. So the flow will look like > > > > 1) if the GPIO is defined with 0 debounce, set the flag; > > 2) if the GPIO is defined with non-zero value, try to apply it; > > 3) if the step 2) fails, warn and set the flag. > > > > Would it make sense? > > Hans? > > But so on these problematic BYT/CYT tablets which "layer" should be > setting the 50ms debounce? > That should still be a quirk at the soc_button_array layer, right? > > Because gpio_keys_setup_key() will already fallback to software > debounce, and the goal here is that both of those only use the 50ms > specifically with software debouncing. Probably gpiod_set_debounce() should become a no-op in this case? -- With Best Regards, Andy Shevchenko
