On Sun, 29 Mar 2020, John Wyatt wrote: > On Sun, 2020-03-29 at 11:28 +0200, Julia Lawall wrote: > > > > On Sun, 29 Mar 2020, John B. Wyatt IV wrote: > > > > > Fix style issue with usleep_range being reported as preferred over > > > udelay. > > > > > > Issue reported by checkpatch. > > > > > > Please review. > > > > > > As written in Documentation/timers/timers-howto.rst udelay is the > > > generally preferred API. hrtimers, as noted in the docs, may be too > > > expensive for this short timer. > > > > > > Are the docs out of date, or, is this a checkpatch issue? > > > > > > Signed-off-by: John B. Wyatt IV <jbwyatt4@xxxxxxxxx> > > > --- > > > drivers/staging/fbtft/fb_agm1264k-fl.c | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > diff --git a/drivers/staging/fbtft/fb_agm1264k-fl.c > > > b/drivers/staging/fbtft/fb_agm1264k-fl.c > > > index eeeeec97ad27..019c8cce6bab 100644 > > > --- a/drivers/staging/fbtft/fb_agm1264k-fl.c > > > +++ b/drivers/staging/fbtft/fb_agm1264k-fl.c > > > @@ -85,7 +85,7 @@ static void reset(struct fbtft_par *par) > > > dev_dbg(par->info->device, "%s()\n", __func__); > > > > > > gpiod_set_value(par->gpio.reset, 0); > > > - udelay(20); > > > + usleep_range(20, 20); > > > > usleep_range should have a range, eg usleep_range(50, 100);. But it > > is > > hard to know a priori what the range should be. So it is probably > > better > > to leave the code alone. > > Understood. > > With the question I wrote in the commit message: > > "As written in Documentation/timers/timers-howto.rst udelay is the > generally preferred API. hrtimers, as noted in the docs, may be too > expensive for this short timer. > > Are the docs out of date, or, is this a checkpatch issue?" > > Is usleep_range too expensive for this operation? > > Why does checkpatch favor usleep_range while the docs favor udelay? I don't know the answer in detail, but it is quite possible that checkpatch doesn't pay any attention to the delay argument. Checkpatch is a perl script that highlights things that may be of concern. It is not a precise static analsis tool. As a matter of form, all of your Please review comments should have been put below the ---. Currently, if someone had wanted to apply the patch, you would make them do extra work to remove this information. julia > > > > > julia > > > > > gpiod_set_value(par->gpio.reset, 1); > > > mdelay(120); > > > } > > > -- > > > 2.25.1 > > > > > > -- > > > You received this message because you are subscribed to the Google > > > Groups "outreachy-kernel" group. > > > To unsubscribe from this group and stop receiving emails from it, > > > send an email to outreachy-kernel+unsubscribe@xxxxxxxxxxxxxxxx. > > > To view this discussion on the web visit > > > https://groups.google.com/d/msgid/outreachy-kernel/20200329092204.770405-1-jbwyatt4%40gmail.com > > > . > > > > > _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
