Re: [PATCH] remoteproc/mtk_scp: surround DT device IDs with CONFIG_OF

[Bjorn Andersson]

On Wed 04 Nov 13:05 CST 2020, Mathieu Poirier wrote:

> Hi Alexander,
> 
> On Mon, Nov 02, 2020 at 04:40:07PM +0900, Alexandre Courbot wrote:
> > Now that this driver can be compiled with COMPILE_TEST, we have no
> > guarantee that CONFIG_OF will also be defined. When that happens, a
> > warning about mtk_scp_of_match being defined but unused will be reported
> > so make sure this variable is only defined if of_match_ptr() actually
> > uses it.
> > 
> > Fixes: cbd2dca74926c0e4610c40923cc786b732c9e8ef remoteproc: scp: add COMPILE_TEST dependency
> > Reported-by: kernel test robot <lkp@xxxxxxxxx>
> > Signed-off-by: Alexandre Courbot <acourbot@xxxxxxxxxxxx>
> > ---
> >  drivers/remoteproc/mtk_scp.c | 2 ++
> >  1 file changed, 2 insertions(+)
> > 
> > diff --git a/drivers/remoteproc/mtk_scp.c b/drivers/remoteproc/mtk_scp.c
> > index 577cbd5d421e..f74f22d4d1ff 100644
> > --- a/drivers/remoteproc/mtk_scp.c
> > +++ b/drivers/remoteproc/mtk_scp.c
> > @@ -772,12 +772,14 @@ static const struct mtk_scp_of_data mt8192_of_data = {
> >  	.host_to_scp_int_bit = MT8192_HOST_IPC_INT_BIT,
> >  };
> >  
> > +#if defined(CONFIG_OF)
> >  static const struct of_device_id mtk_scp_of_match[] = {
> >  	{ .compatible = "mediatek,mt8183-scp", .data = &mt8183_of_data },
> >  	{ .compatible = "mediatek,mt8192-scp", .data = &mt8192_of_data },
> >  	{},
> >  };
> >  MODULE_DEVICE_TABLE(of, mtk_scp_of_match);
> > +#endif
> 
> I think it is better to add a "depends on OF" in the Kconfig.
> 

That would reduce the efficiency of COMPILE_TEST, so I would prefer that
we drop of_match_ptr(), which will result in the pointer always being
populated and this being referenced - although unused when built without
OF.

Regards,
Bjorn