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

[Meagan Lloyd]

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?