Re: [RFC PATCH V2] Input: elan_i2c_smbus - resend ENABLE_TP on wake from sleep (NOT TESTED, NEEDS TESTER!) (v2: typo fixes)

[Dmitry Torokhov]

Hi Raphaël,

On Tue, Sep 22, 2026 at 07:35:47PM -0400, R. Larocque wrote:
> From: "Raphaël Larocque" <rlarocque@xxxxxxxxxxx>
> 
> elan_smbus_sleep_control() sends ETP_SMBUS_SLEEP_CMD to put the
> controller to sleep, but does nothing on wake, leaving a long-standing
> XXX comment questioning whether ETP_SMBUS_ENABLE_TP should be re-sent.
> 
> elan_initialize() already treats sleep_control(client, false) as a
> genuine "wake device up" primitive (see the ASUS special-firmware
> branch and its accompanying dev_err() message), so this makes the
> non-ASUS/default path resend ETP_SMBUS_ENABLE_TP symmetrically with
> elan_smbus_initialize() instead of being a no-op.
> 
> Signed-off-by: Raphaël Larocque <rlarocque@xxxxxxxxxxx>
> ---
> RFC: I don't have the Elan SMBus protocol datasheet and consequently 
> haven't been able to test this on any real hardware where the previous no-op
> path was actually relied upon. Sending this for testing by
> someone with access to affected devices before it is considered for
> merge. A bad SMBus write to a sleeping controller could leave it
> in a weird state on the wrong firmware revision if unlucky.

I do not have objections in principle, but this really needs testing on
real hardware... 

Thanks.

-- 
Dmitry