[RFC PATCH] mmc: host: sdhci-iproc: implement the .hw_reset callback

[Florian Fainelli]

On 4/15/26 13:43, Meagan Lloyd wrote:
> 
> On 4/15/2026 1:23 PM, Scott Branden wrote:
>> Hi Meagan,
>>
>> On Wed, Apr 15, 2026 at 11:08 AM Meagan Lloyd <
>> meaganlloyd at linux.microsoft.com> wrote:
>>
>>> On 4/13/2026 10:43 AM, Florian Fainelli wrote:
>>>> On 4/13/26 10:38, Meagan Lloyd wrote:
>>>>> On 3/27/2026 3:21 PM, Meagan Lloyd wrote:
>>>>>> Implement the .hw_reset callback so that the eMMC can be reset as
>>>>>> needed
>>>>>> given cap-mmc-hw-reset is set in the devicetree and the
>>>>>> functionality is
>>>>>> enabled on the eMMC.
>>>>>>
>>>>>> Signed-off-by: Meagan Lloyd <meaganlloyd at linux.microsoft.com>
>>>>>> ---
>>>>>>
>>>>>> SDHCI_POWER_CONTROL[4] (SD Host Controller Standard) has been
>>>>>> repurposed
>>>>>> on my Broadcomm processor to be eMMC hardware reset
>>>>>> (SDIO*_eMMCSDXC_CTRL[12], HRESET).
>>>>>>
>>>>>> Can you confirm this repurposed bit is consistent across the Broadcomm
>>>>>> iProc processors and thus the .hw_reset callback can be uniformly
>>>>>> applied in this driver?
>>>>> Hi Ray & Scott,
>>>>>
>>>>> I hope you're doing well. This bit looks to have been repurposed from
>>>>> the SD Host Controller Standard's VDD2 Power Control to being used for
>>>>> toggling the hardware reset signal to eMMCs. Can you verify that it
>>>>> applies across the iProc processors so that I may finalize this patch?
>>>> Which iProc process are you using? If you are not sure this applies
>>>> broadly, can you at least make it specific to the SoC you are using?
>>> Yes, if it comes to that I can. I think it's overkill to roll a new
>>> compat string/associated structures over this small change, hence
>>> checking with Broadcomm iProc maintainers on this thread.
>>>
>> Which iProc processor are you using?  You will have to check with
>> RaspberryPI as I think they use this driver as well.
>> If that family also supports it then you probably don't need a
>> compatibility string.
> 
> The processor I am using is the BCM58732. Can you help direct me to
> someone who could comment from the RaspberryPi side?
> 

I will take care of that.
-- 
Florian