On Wed, Nov 25, 2020 at 03:24:20PM +0200, Andy Shevchenko wrote:
On Wed, Nov 25, 2020 at 3:03 PM Coiby Xu <coiby.xu@xxxxxxxxx> wrote:
Debounce filter setting should be independent from IRQ type setting
because according to the ACPI specs, there are separate arguments for
specifying debounce timeout and IRQ type in GpioIo() and GpioInt().
Together with commit 06abe8291bc31839950f7d0362d9979edc88a666
("pinctrl: amd: fix incorrect way to disable debounce filter") and
Andy's patch "gpiolib: acpi: Take into account debounce settings" [1],
this will fix broken touchpads for laptops whose BIOS set the
debounce timeout to a relatively large value. For example, the BIOS
of Lenovo AMD gaming laptops including Legion-5 15ARH05 (R7000),
Legion-5P (R7000P) and IdeaPad Gaming 3 15ARH05, set the debounce
timeout to 124.8ms. This led to the kernel receiving only ~7 HID
reports per second from the Synaptics touchpad
(MSFT0001:00 06CB:7F28).
Existing touchpads like [2][3] are not troubled by this bug because
the debounce timeout has been set to 0 by the BIOS before enabling
the debounce filter in setting IRQ type.
[1] https://lore.kernel.org/linux-gpio/20201111222008.39993-11-andriy.shevchenko@xxxxxxxxxxxxxxx/
JFYI: this is nowadays
8dcb7a15a585 ("gpiolib: acpi: Take into account debounce settings")
Thank you for the info! Next time I will also check the linux-next
tree:)
(No need to recend, just an information that can be applied maybe by Linus)
[2] https://github.com/Syniurge/i2c-amd-mp2/issues/11#issuecomment-721331582
[3] https://forum.manjaro.org/t/random-short-touchpad-freezes/30832/28
--
With Best Regards,
Andy Shevchenko
--
Best regards,
Coiby
