RE: [PATCH] drm/amdgpu/display: add fallthrough comment

[Liu, Zhan]

> -----Original Message-----
> From: Alex Deucher <alexdeuc...@gmail.com>
> Sent: 2019/December/05, Thursday 5:13 PM
> To: Liu, Zhan <zhan....@amd.com>
> Cc: amd-gfx@lists.freedesktop.org; Deucher, Alexander
> <alexander.deuc...@amd.com>
> Subject: Re: [PATCH] drm/amdgpu/display: add fallthrough comment
> 
> On Thu, Dec 5, 2019 at 5:10 PM Liu, Zhan <zhan....@amd.com> wrote:
> >
> >
> >
> > > -----Original Message-----
> > > From: amd-gfx <amd-gfx-boun...@lists.freedesktop.org> On Behalf Of
> > > Alex Deucher
> > > Sent: 2019/December/05, Thursday 4:39 PM
> > > To: amd-gfx@lists.freedesktop.org
> > > Cc: Deucher, Alexander <alexander.deuc...@amd.com>
> > > Subject: [PATCH] drm/amdgpu/display: add fallthrough comment
> > >
> > > To avoid a compiler warning.
> > >
> > > Signed-off-by: Alex Deucher <alexander.deuc...@amd.com>
> > > ---
> > >  drivers/gpu/drm/amd/display/dc/dce/dce_aux.c | 1 +
> > >  1 file changed, 1 insertion(+)
> > >
> > > diff --git a/drivers/gpu/drm/amd/display/dc/dce/dce_aux.c
> > > b/drivers/gpu/drm/amd/display/dc/dce/dce_aux.c
> > > index 191b68b8163a..f1a5d2c6aa37 100644
> > > --- a/drivers/gpu/drm/amd/display/dc/dce/dce_aux.c
> > > +++ b/drivers/gpu/drm/amd/display/dc/dce/dce_aux.c
> > > @@ -645,6 +645,7 @@ bool dce_aux_transfer_with_retries(struct
> > > ddc_service *ddc,
> > >                       case AUX_TRANSACTION_REPLY_AUX_DEFER:
> > >                       case
> > > AUX_TRANSACTION_REPLY_I2C_OVER_AUX_DEFER:
> > >                               retry_on_defer = true;
> > > +                             /* fall through */
> >
> > I am a bit confusing here. Why a comment can avoid a compiler warning?
> 
> The kernel enables fall through warnings, so unless there is a comment
> mentioning that are are expecting to fall through here, we get a warning.
> The idea is to find missing breaks in switch code.
> 
> Alex

Got you. Thank you for your explanation.

Reviewed-by: Zhan Liu <zhan....@amd.com>

> 
> >
> > >                       case
> > > AUX_TRANSACTION_REPLY_I2C_OVER_AUX_NACK:
> > >                               if (++aux_defer_retries >=
> > > AUX_MAX_DEFER_RETRIES) {
> > >                                       goto fail;
> > > --
> > > 2.23.0
> > >
> > > _______________________________________________
> > > amd-gfx mailing list
> > > amd-gfx@lists.freedesktop.org
> > >
> https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.
> > > freedesktop.org%2Fmailman%2Flistinfo%2Famd-
> > >
> gfx&amp;data=02%7C01%7Czhan.liu%40amd.com%7C77d85a0275aa4c0a78
> > >
> 2f08d779cb9716%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C6
> > >
> 37111788208702340&amp;sdata=3m%2FuNuNIgq82z%2BAeXJ9y7wn81kV%
> > > 2FiDt3AyC3CDiTRrc%3D&amp;reserved=0
_______________________________________________
amd-gfx mailing list
amd-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/amd-gfx