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

[Chaotian Jing]

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.