Re: i8042_init: PS/2 mouse not detected with ACPIPnP/PnPBIOS

[Dmitry Torokhov]

Hi Paul,

On Wed, Oct 07, 2020 at 11:18:41PM +0200, Paul Menzel wrote:
> Dear Linux folks,
> 
> 
> On the Asus F2A85-M PRO Linux 5.9-rc8 (and previous versions) does not
> recognize a plugged in PS/2 mouse using the Plug & Play method. The PS/2
> keyboard is detected fine, and using `i8042.nopnp`, the PS/2 mouse also
> works.
> 
> > [    1.035915] calling  i8042_init+0x0/0x42d @ 1
> > [    1.035947] i8042: PNP: PS/2 Controller [PNP0303:PS2K] at 0x60,0x64 irq 1
> > [    1.035948] i8042: PNP: PS/2 appears to have AUX port disabled, if this is incorrect please boot with i8042.nopnp
> > [    1.036589] serio: i8042 KBD port at 0x60,0x64 irq 1
> > [    1.036621] initcall i8042_init+0x0/0x42d returned 0 after 687 usecs
> 
> But, the DSDT includes the “mouse device”. From
> 
>     acpidump > dump.bin; acpixtract dump.bin; iasl -d *dat; more dsdt.dsl
> 
> we get
> 
>                 Device (PS2M)
>                 {
>                     Name (_HID, EisaId ("PNP0F03") /* Microsoft PS/2-style
> Mouse */)  // _HID: Hardware ID
>                     Name (_CID, EisaId ("PNP0F13") /* PS/2 Mouse */) //
> _CID: Compatible ID
>                     Method (_STA, 0, NotSerialized)  // _STA: Status
>                     {
>                         If ((IOST & 0x4000))
>                         {
>                             Return (0x0F)
>                         }
>                         Else
>                         {
>                             Return (Zero)
>                         }
>                     }
> 
> and the identifiers PNP0F03 and PNP0F13 are both listed in the array
> `pnp_aux_devids[]`. But adding print statements to `i8042_pnp_aux_probe()`,
> I do not see them, so the function does not seem to be called.

My guess is that _STA returns 0 indicating that the device is not
present. I would try tracking where IOST is being set and figuring out
why it does not have mouse bit enabled.

Thanks.

-- 
Dmitry