Re: [PATCH RESEND v2 1/2] Input: touchscreen: ads7846: keep copy of pdata in private struct

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

On Mon, Jul 01, 2013 at 09:14:04AM +0200, Daniel Mack wrote:
> On 01.07.2013 09:09, Dmitry Torokhov wrote:
> > Hi Daniel,
> > 
> > On Mon, Jul 01, 2013 at 08:48:50AM +0200, Daniel Mack wrote:
> >> Hi Dmitry,
> >>
> >> On 01.07.2013 03:33, Dmitry Torokhov wrote:
> >>> On Sun, Jun 30, 2013 at 11:09:14PM +0200, Daniel Mack wrote:
> >>>> +
> >>>> +	if (!pdata->model)
> >>>> +		pdata->model = 7846;
> >>>> +
> >>>> +	if (!pdata->vref_delay_usecs)
> >>>> +		pdata->vref_delay_usecs = 100;
> >>>> +
> >>>> +	if (!pdata->x_plate_ohms)
> >>>> +		pdata->x_plate_ohms = 400;
> >>>> +
> >>>> +	if (!pdata->pressure_max)
> >>>> +		pdata->pressure_max = ~0;
> >>>
> >>> We should not be changing the platform data as the device does not own
> >>> it and it may well be declared as a constant structure.
> >>
> >> We don't change the platform data that is passed in via the driver core.
> >> We keep a copy of it in our private strucz (that's what the subject
> >> says) and in case of DT, we modify that copy. The passed pdata is left
> >> untouched.
> >>
> > 
> > That might have been the intent but the patch only stores a _pointer_ to
> > the platform data in the main structure, so in non-DT case you end up
> > modifying the original structure.
> 
> Eh, ok. I'll change that to always make a copy. Somehow though, I like
> the first approach (v1 of the set) better, which stored all data that is
> modified inside the private struct directly.
> 
> Anyway, I'll submit v3 later.

No, there is no need, the other patch (adding DT bindings) should work
just fine without this one.

Thanks.

-- 
Dmitry