Hi,

On 11/10/20 9:26 AM, Coiby Xu wrote:

On Mon, Nov 09, 2020 at 02:52:17PM +0100, Hans de Goede wrote:

...

Hi,

On 11/6/20 12:19 AM, Coiby Xu 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().

This will fix broken touchpads for laptops whose BIOS set the debounce timeout to a relatively large value. For example, the BIOS of Lenovo Legion-5 AMD gaming laptops including 15ARH05 (R7000) and R7000P 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 [1][2] 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://github.com/Syniurge/i2c-amd-mp2/issues/11#issuecomment-721331582 [2] https://forum.manjaro.org/t/random-short-touchpad-freezes/30832/28

Cc: Hans de Goede hdegoede@redhat.com Cc: Andy Shevchenko andy.shevchenko@gmail.com Cc: Benjamin Tissoires benjamin.tissoires@redhat.com Cc: stable@vger.kernel.org Reviewed-by: Andy Shevchenko andy.shevchenko@gmail.com BugLink: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1887190 Link: https://lore.kernel.org/linux-gpio/CAHp75VcwiGREBUJ0A06EEw-SyabqYsp%2Bdqs2Dp... Signed-off-by: Coiby Xu coiby.xu@gmail.com

I'm not entirely sure about this patch. This is consistent with how we already stopped touching the debounce timeout setting during init, so that speaks in favor of this change.

Still I'm worried a bit that this might have undesirable side effects.

Now I can only confirm this patch won't affect the mentioned touchpads. I'll see if other distributions like Manjaro are willing to test it through the unstable channel.

...

I guess this should be landed together with Andy's series to apply the debounce setting from the ACPI GPIO resources.

Thank you for the reminding! You are right, Andy's patch "gpiolib: acpi: Take into account debounce settings" is needed to fix this kind of touchpad issues. Since that patch hasn't been merged, is there a way to refer to it in the commit message?

You can always refer to it by subject, as you did above.

Regards,

Hans

...

...

---

drivers/pinctrl/pinctrl-amd.c | 7 -------  1 file changed, 7 deletions(-)

diff --git a/drivers/pinctrl/pinctrl-amd.c b/drivers/pinctrl/pinctrl-amd.c index e9b761c2b77a..2d4acf21117c 100644 --- a/drivers/pinctrl/pinctrl-amd.c +++ b/drivers/pinctrl/pinctrl-amd.c @@ -468,7 +468,6 @@ static int amd_gpio_irq_set_type(struct irq_data *d, unsigned int type)          pin_reg &= ~BIT(LEVEL_TRIG_OFF);          pin_reg &= ~(ACTIVE_LEVEL_MASK << ACTIVE_LEVEL_OFF);          pin_reg |= ACTIVE_HIGH << ACTIVE_LEVEL_OFF; -        pin_reg |= DB_TYPE_REMOVE_GLITCH << DB_CNTRL_OFF;          irq_set_handler_locked(d, handle_edge_irq);          break;

@@ -476,7 +475,6 @@ static int amd_gpio_irq_set_type(struct irq_data *d, unsigned int type)          pin_reg &= ~BIT(LEVEL_TRIG_OFF);          pin_reg &= ~(ACTIVE_LEVEL_MASK << ACTIVE_LEVEL_OFF);          pin_reg |= ACTIVE_LOW << ACTIVE_LEVEL_OFF; -        pin_reg |= DB_TYPE_REMOVE_GLITCH << DB_CNTRL_OFF;          irq_set_handler_locked(d, handle_edge_irq);          break;

@@ -484,7 +482,6 @@ static int amd_gpio_irq_set_type(struct irq_data *d, unsigned int type)          pin_reg &= ~BIT(LEVEL_TRIG_OFF);          pin_reg &= ~(ACTIVE_LEVEL_MASK << ACTIVE_LEVEL_OFF);          pin_reg |= BOTH_EADGE << ACTIVE_LEVEL_OFF; -        pin_reg |= DB_TYPE_REMOVE_GLITCH << DB_CNTRL_OFF;          irq_set_handler_locked(d, handle_edge_irq);          break;

@@ -492,8 +489,6 @@ static int amd_gpio_irq_set_type(struct irq_data *d, unsigned int type)          pin_reg |= LEVEL_TRIGGER << LEVEL_TRIG_OFF;          pin_reg &= ~(ACTIVE_LEVEL_MASK << ACTIVE_LEVEL_OFF);          pin_reg |= ACTIVE_HIGH << ACTIVE_LEVEL_OFF; -        pin_reg &= ~(DB_CNTRl_MASK << DB_CNTRL_OFF); -        pin_reg |= DB_TYPE_PRESERVE_LOW_GLITCH << DB_CNTRL_OFF;          irq_set_handler_locked(d, handle_level_irq);          break;

@@ -501,8 +496,6 @@ static int amd_gpio_irq_set_type(struct irq_data *d, unsigned int type)          pin_reg |= LEVEL_TRIGGER << LEVEL_TRIG_OFF;          pin_reg &= ~(ACTIVE_LEVEL_MASK << ACTIVE_LEVEL_OFF);          pin_reg |= ACTIVE_LOW << ACTIVE_LEVEL_OFF; -        pin_reg &= ~(DB_CNTRl_MASK << DB_CNTRL_OFF); -        pin_reg |= DB_TYPE_PRESERVE_HIGH_GLITCH << DB_CNTRL_OFF;          irq_set_handler_locked(d, handle_level_irq);          break;

-- Best regards, Coiby