Re: [PATCH] Input: elan_i2c - add ASUS EeeBook X205TA special touchpad fw

[MatjaÅ HegediÄ]

Hi Dmitry, KT!

On 2017-03-07 08:05, 廖崇榮 wrote:
> Hi Dmitry
>
> -----Original Message-----
> From: Dmitry Torokhov [mailto:dmitry.torokhov@xxxxxxxxx]
> Sent: Tuesday, March 07, 2017 3:55 AM
> To: KT Liao
> Cc: linux-input@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Matjaz
> Hegedic
> Subject: Re: [PATCH] Input: elan_i2c - add ASUS EeeBook X205TA special
> touchpad fw
>
> On Sun, Mar 05, 2017 at 03:13:02AM +0100, Matjaz Hegedic wrote:
> > EeeBook X205TA is yet another ASUS device with a special touchpad
> > firmware that needs to be accounted for during initialization, or else
> > the touchpad will go into an invalid state upon suspend/resume.
> > Adding the appropriate ic_type and product_id check fixes the problem.
>
> KT, does this look reasonable? Are there more ASUS models that need such
> handling?
> [KT] : I just discuss it with FW team.
> We can't confirm it right now because it's an old product. And the solution
> focus on power-on issue, not suspend/resume.
> I will let you know once we figure it out.
>
> Our FW has modified, the issue should not happen on new models.
>
> Thanks		KT

As it is now, the touchpad will stop working upon resume, returning an
invalid id (and requires a cumbersome workaround of reloading the 
module). As the touchpad FW is opaque to me, the only way I could 
resolve the bug was through trial-and-error. Including the touchpad in 
the 'special fw' resolves the bug and the touchpad resumes without issue.

Now, even if the function is indeed used to resolve a different issue on 
other ASUS touchpads, I would argue that this is the most pragmatic way 
of resolving the problem on X205TA, X205TAW and F205TA (and possibly 
also X200HA & X206HA, though I don't have those to test).

It shouldn't affect any other models or touchpad products.

Thanks!

> > Signed-off-by: Matjaz Hegedic <matjaz.hegedic@xxxxxxxxx>
> > ---
> >  drivers/input/mouse/elan_i2c_core.c | 22 ++++++++++++----------
> >  1 file changed, 12 insertions(+), 10 deletions(-)
> >
> > diff --git a/drivers/input/mouse/elan_i2c_core.c
> > b/drivers/input/mouse/elan_i2c_core.c
> > index 2c7d287..dde3ad7 100644
> > --- a/drivers/input/mouse/elan_i2c_core.c
> > +++ b/drivers/input/mouse/elan_i2c_core.c
> > @@ -218,17 +218,19 @@ static int elan_query_product(struct
> > elan_tp_data *data)
> >
> >  static int elan_check_ASUS_special_fw(struct elan_tp_data *data)  {
> > -	if (data->ic_type != 0x0E)
> > -		return false;
> > -
> > -	switch (data->product_id) {
> > -	case 0x05 ... 0x07:
> > -	case 0x09:
> > -	case 0x13:
> > -		return true;
> > -	default:
> > -		return false;
> > +	if (data->ic_type == 0x0E) {
> > +		switch (data->product_id) {
> > +		case 0x05 ... 0x07:
> > +		case 0x09:
> > +		case 0x13:
> > +			return true;
> > +		}
> >  	}
> > +	/* ASUS EeeBook X205TA */
> > +	else if (data->ic_type == 0x8 && data->product_id == 0x26)
> > +		return true;
> > +
> > +	return false;
> >  }
> >
> >  static int __elan_initialize(struct elan_tp_data *data)
> > --
> > 2.7.4
>
> Thanks.