On Fri, Feb 11, 2022 at 11:40:13AM +0100, Javier Martinez Canillas wrote:
> On 2/11/22 11:28, Andy Shevchenko wrote:
> > On Fri, Feb 11, 2022 at 10:19:22AM +0100, Javier Martinez Canillas wrote:
...
> >> +static void drm_fb_xrgb8888_to_gray8_line(u8 *dst, const u32 *src, unsigned int pixels)
> >> +{
> >> + unsigned int x;
> >> +
> >> + for (x = 0; x < pixels; x++) {
> >> + u8 r = (*src & 0x00ff0000) >> 16;
> >> + u8 g = (*src & 0x0000ff00) >> 8;
> >> + u8 b = *src & 0x000000ff;
> >> +
> >> + /* ITU BT.601: Y = 0.299 R + 0.587 G + 0.114 B */
> >> + *dst++ = (3 * r + 6 * g + b) / 10;
> >> + src++;
> >> + }
> >
> > Can be done as
> >
> > while (pixels--) {
> > ...
> > }
> >
> > or
> >
> > do {
> > ...
> > } while (--pixels);
> >
>
> I don't see why a while loop would be an improvement here TBH.
Less letters to parse when reading the code.
> In any case, I just pulled the line conversion logic as a separate
> function with minimal code changes since doing that should be in a
> separate patch.
> Feel free to post a patch if you want to change that while loop.
Perhaps some day :-)
--
With Best Regards,
Andy Shevchenko
