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.
