Re: [PATCH 1/1] V4L: stk11xx, add a new webcam driver

[Jiri Slaby]

On 5/25/07, Stefan Richter <stefanr@xxxxxxxxxxxxxxxxx> wrote:
> Jiri Slaby wrote:
> > On 5/24/07, Markus Rechberger <mrechberger@xxxxxxxxx> wrote:
> >> On 5/24/07, Jiri Slaby <jirislaby@xxxxxxxxx> wrote:
> > [...]
> >> > +static int stk1125_camera_asleep(struct stk11xx *dev)
> >> > +{
> >> > +     int value;
> >> > +
> >> > +     stk11xx_read_registry(dev, 0x0104, &value);
> >> > +     stk11xx_read_registry(dev, 0x0105, &value);
> >> > +     stk11xx_read_registry(dev, 0x0106, &value);
> >> > +
> >>
> >> why do you read these values (this is also something in the ongoing
> >> code I see, the read value just gets overwritten all the time)?
> >
> > Well, as I tested, reads are neccesary, otherwise it doesn't work. And
> > when they are needed, you need to read the value to some place in
> > memory -- the &value.
>
> Perhaps a few comments are warranted here and there about why some of
> those less obvious things are done.
>
> Or do it as more or less self-documenting code like
>
> static inline void
> stk11xx_unjam_registry(struct stk11xx *dev, u16 index)
> {
>         int dummy;
>
>         stk11xx_read_registry(dev, index, &dummy);
> }

yeah, seems reasonable to me.

thanks,
--
http://www.fi.muni.cz/~xslaby/            Jiri Slaby
faculty of informatics, masaryk university, brno, cz
e-mail: jirislaby gmail com, gpg pubkey fingerprint:
B674 9967 0407 CE62 ACC8  22A0 32CC 55C3 39D4 7A7E
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