Re: [PATCH v3 01/12] mmc: mediatek: add support of mt2701/mt2712

[Matthias Brugger]

On 10/10/2017 10:22 AM, Chaotian Jing wrote:
> On Tue, 2017-10-10 at 10:09 +0200, Ulf Hansson wrote:
> > On 10 October 2017 at 09:35, Chaotian Jing <chaotian.jing@xxxxxxxxxxxx> wrote:
> > > On Tue, 2017-10-10 at 09:26 +0200, Ulf Hansson wrote:
> > > > [...]
> > > >
> > > > > +
> > > > > +static const struct of_device_id msdc_of_ids[] = {
> > > > > +       { .compatible = "mediatek,mt8135-mmc", .data = &mt8135_compat},
> > > > > +       { .compatible = "mediatek,mt8173-mmc", .data = &mt8173_compat},
> > > > > +       { .compatible = "mediatek,mt2701-mmc", .data = &mt2701_compat},
> > > > > +       { .compatible = "mediatek,mt2712-mmc", .data = &mt2712_compat},
> > > > > +       {}
> > > > > +};
> > > > > +MODULE_DEVICE_TABLE(of, msdc_of_ids);
> > > >
> > > > As already stated in the other reply. These new compatible changes
> > > > needs to be discussed and acked before the driver starts using them.
> > > >
> > > > In other words, make patch3 to precede this one.
> > > but, then there will have a probe issue as mentioned in previous mail
> > > list. that's why I separate the binding file changes to 2 patches.
> >
> > That sounds seriously wrong. Aren't the bindings backwards compatible?
> >
> > Kind regards
> > Uffe
>
> As Matthias mentioned before:
> "
> > > NAK, this has to be:
> > > You have to add the fallback compatible ("mediatek,mt8135-mmc") to
> the binding
> > > description as otherwise the driver does not get probed.
> > >
> > > Regards,
> > > Matthias
> "
> the original compatible in driver is "mediatek,mt8135-mmc", so that if
> drop "mediatek,mt8135-mmc" in bindings file(User may refer it and drop
> "mediatek,mt8135-mmc" in their DTS), the driver will not get probed.

If you change the driver as you did in this patch, then there is no probing problem.

Regards,
Matthias