Re: [PATCH v3] mmc: dt-bindings: Add reg/source_cg/latch-ck for Mediatek MMC bindings

[Matthias Brugger <matthias.bgg@gmail.com>]

On 09/29/2017 01:50 PM, Chaotian Jing wrote:
> On Fri, 2017-09-29 at 13:11 +0200, Matthias Brugger wrote:
>>
>> On 09/22/2017 02:03 PM, Chaotian Jing wrote:
>>> Change the comptiable for support of multi-platform
>>> Add description for reg
>>> Add description for source_cg
>>> Add description for mediatek,latch-ck
>>> Note that source_cg and mediatek,latch-ck are optional for some projects,
>>> eg, MT2701 do not have source_cg, and MT2712 do not need
>>> mediatek,latch-ck
>>>
>>> Signed-off-by: Chaotian Jing <chaotian.jing@mediatek.com>
>>> ---
>>>    Documentation/devicetree/bindings/mmc/mtk-sd.txt | 13 ++++++++++---
>>>    1 file changed, 10 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/Documentation/devicetree/bindings/mmc/mtk-sd.txt b/Documentation/devicetree/bindings/mmc/mtk-sd.txt
>>> index 4182ea3..b934a29 100644
>>> --- a/Documentation/devicetree/bindings/mmc/mtk-sd.txt
>>> +++ b/Documentation/devicetree/bindings/mmc/mtk-sd.txt
>>> @@ -7,10 +7,15 @@ This file documents differences between the core properties in mmc.txt
>>>    and the properties used by the msdc driver.
>>>    
>>>    Required properties:
>>> -- compatible: Should be "mediatek,mt8173-mmc","mediatek,mt8135-mmc"
>>> +- compatible: value should be either of the following.
>>> +	"mediatek,mt8135-mmc": for mmc host ip compatible with mt8135
>>> +	"mediatek,mt8173-mmc": for mmc host ip compatible with mt8173
>>> +	"mediatek,mt2701-mmc": for mmc host ip compatible with mt2701
>>> +	"mediatek,mt2712-mmc": for mmc host ip compatible with mt2712
>>
>> 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
> 
> Thanks for your comments, will add the fallback compatible
> ("mediatek,mt8135-mmc") to the binding in this patch.
> but, is possible to remove the fallback compatible at next patch ?
> eg, following patches will modify the driver like below:
> static const struct of_device_id msdc_of_ids[] = {
>          { .compatible = "mediatek,mt8135-mmc", .data = &mt8135_compat},
>          { .compatible = "mediatek,mt8173-mmc", .data = &mt8173_compat},
> };
> then, there is no probe issue and remove the fallback compatible.
> Thx!

Right, if you have an explicit compatible in the driver, we don't need the 
fallback. But it doesn't hurt neither. As you like.

Regards,
Matthias

>>
>>> +- reg: physical base address of the controller and length
>>>    - interrupts: Should contain MSDC interrupt number
>>> -- clocks: MSDC source clock, HCLK
>>> -- clock-names: "source", "hclk"
>>> +- clocks: MSDC source clock, HCLK, source_cg
>>> +- clock-names: "source", "hclk", "source_cg"
>>>    - pinctrl-names: should be "default", "state_uhs"
>>>    - pinctrl-0: should contain default/high speed pin ctrl
>>>    - pinctrl-1: should contain uhs mode pin ctrl
>>> @@ -30,6 +35,8 @@ Optional properties:
>>>    - mediatek,hs400-cmd-resp-sel-rising:  HS400 command response sample selection
>>>    				       If present,HS400 command responses are sampled on rising edges.
>>>    				       If not present,HS400 command responses are sampled on falling edges.
>>> +- mediatek,latch-ck: Some SoCs do not support enhance_rx, need set correct latch-ck to avoid data crc
>>> +		     error caused by stop clock(fifo full)
>>>    
>>>    Examples:
>>>    mmc0: mmc@11230000 {
>>>
> 
>