Re: [PATCH] platform/x86: ideapad-laptop: Stop calling i8042_command()

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

On Mon, Aug 05, 2024 at 04:16:08PM +0200, Hans de Goede wrote:
> Commit 07a4a4fc83dd ("ideapad: add Lenovo IdeaPad Z570 support (part 2)")
> added an i8042_command(..., I8042_CMD_AUX_[EN|DIS]ABLE) call to
> the ideapad-laptop driver to suppress the touchpad events at the PS/2
> AUX controller level.
> 
> Commit c69e7d843d2c ("platform/x86: ideapad-laptop: Only toggle ps2 aux
> port on/off on select models") limited this to only do this by default
> on the IdeaPad Z570 to replace a growing list of models on which
> the i8042_command() call was disabled by quirks because it was causing
> issues.
> 
> A recent report shows that this is causing issues even on the Z570 for
> which it was originally added because it can happen on resume before
> the i8042 controller's own resume() method has run:
> 
> [   50.241235] ideapad_acpi VPC2004:00: PM: calling acpi_subsys_resume+0x0/0x5d @ 4492, parent: PNP0C09:00
> [   50.242055] snd_hda_intel 0000:00:0e.0: PM: pci_pm_resume+0x0/0xed returned 0 after 13511 usecs
> [   50.242120] snd_hda_codec_realtek hdaudioC0D0: PM: calling hda_codec_pm_resume+0x0/0x19 [snd_hda_codec] @ 4518, parent: 0000:00:0e.0
> [   50.247406] i8042: [49434] a8 -> i8042 (command)
> [   50.247468] ideapad_acpi VPC2004:00: PM: acpi_subsys_resume+0x0/0x5d returned 0 after 6220 usecs
> ...
> [   50.247883] i8042 kbd 00:01: PM: calling pnp_bus_resume+0x0/0x9d @ 4492, parent: pnp0
> [   50.247894] i8042 kbd 00:01: PM: pnp_bus_resume+0x0/0x9d returned 0 after 0 usecs
> [   50.247906] i8042 aux 00:02: PM: calling pnp_bus_resume+0x0/0x9d @ 4492, parent: pnp0
> [   50.247916] i8042 aux 00:02: PM: pnp_bus_resume+0x0/0x9d returned 0 after 0 usecs
> ...
> [   50.248301] i8042 i8042: PM: calling platform_pm_resume+0x0/0x41 @ 4492, parent: platform
> [   50.248377] i8042: [49434] 55 <- i8042 (flush, kbd)
> [   50.248407] i8042: [49435] aa -> i8042 (command)
> [   50.248601] i8042: [49435] 00 <- i8042 (return)
> [   50.248604] i8042: [49435] i8042 controller selftest: 0x0 != 0x55
> 
> Dmitry (input subsys maintainer) pointed out that just sending
> KEY_TOUCHPAD_OFF/KEY_TOUCHPAD_ON which the ideapad-laptop driver
> already does should be sufficient and that it then is up to userspace
> to filter out touchpad events after having received a KEY_TOUCHPAD_OFF.
> 
> Given all the problems the i8042_command() call has been causing just
> removing it indeed seems best, so this removes it completely. Note that
> this only impacts the Ideapad Z570 since it was already disabled by
> default on all other models.

Right, I think stopping using it here is the best. I also had a draft of
a patch to allow establishing a link between i8042 driver and users of
i8042_command() so that they do not disturb resuming of the keyboard
controller. I need to finish it.

> 
> Fixes: c69e7d843d2c ("platform/x86: ideapad-laptop: Only toggle ps2 aux port on/off on select models")
> Reported-by: Jonathan Denose <jdenose@chromium.org>
> Closes: https://lore.kernel.org/linux-input/20231102075243.1.Idb37ff8043a29f607beab6440c32b9ae52525825@changeid/
> Suggested-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> Cc: Maxim Mikityanskiy <maxtram95@gmail.com>
> Cc: stable@vger.kernel.org
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>

FWIW:

Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Thanks.

-- 
Dmitry