From mboxrd@z Thu Jan  1 00:00:00 1970
From: Matthias Brugger <matthias.bgg@gmail.com>
Subject: Re: [PATCH v3 01/12] mmc: mediatek: add support of mt2701/mt2712
Date: Tue, 10 Oct 2017 10:32:39 +0200
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To: Chaotian Jing <chaotian.jing@mediatek.com>, Ulf Hansson <ulf.hansson@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>, Mark Rutland <mark.rutland@arm.com>, Catalin Marinas <catalin.marinas@arm.com>, Will Deacon <will.deacon@arm.com>, yong mao <yong.mao@mediatek.com>, Linus Walleij <linus.walleij@linaro.org>, Heiner Kallweit <hkallweit1@gmail.com>, Phong LE <ple@baylibre.com>, "linux-mmc@vger.kernel.org" <linux-mmc@vger.kernel.org>, "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>, "linux-arm-kernel@lists.infradead.org" <linux-arm-kernel@lists.infradead.org>, linux-mediatek@lists.infradead.org, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, srv_heupstream <srv_heupstream@mediatek.com>
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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@mediatek.com> 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