[PATCH] mmc: mmci: stm32: add SDIO in-band interrupt mode

[Yann Gautier]

On 9/1/23 16:10, Linus Walleij wrote:
> Hi Yann/Christophe,
> 
> thanks for your patch!

Hi Linus

Thanks for the review, I agree with the proposed changes.
I'll prepare a new version and send it next week!

Best regards,
Yann
> 
> On Fri, Sep 1, 2023 at 2:08 PM Yann Gautier <yann.gautier at foss.st.com> wrote:
> 
>> From: Christophe Kerello <christophe.kerello at foss.st.com>
>>
>> Add the support of SDIO in-band interrupt mode for STM32 variant.
>> It allows the SD I/O card to interrupt the host on SDMMC_D1 data line.
>>
>> Signed-off-by: Christophe Kerello <christophe.kerello at foss.st.com>
>> Signed-off-by: Yann Gautier <yann.gautier at foss.st.com>
> (...)
>> +++ b/drivers/mmc/host/mmci.h
>> @@ -332,6 +332,7 @@ enum mmci_busy_state {
>>    * @opendrain: bitmask identifying the OPENDRAIN bit inside MMCIPOWER register
>>    * @dma_lli: true if variant has dma link list feature.
>>    * @stm32_idmabsize_mask: stm32 sdmmc idma buffer size.
>> + * @use_sdio_irq: allow SD I/O card to interrupt the host
> 
> The documentation tag should be one line up (compare to the members...)
> 
>> @@ -376,6 +377,7 @@ struct variant_data {
>>          u32                     start_err;
>>          u32                     opendrain;
>>          u8                      dma_lli:1;
>> +       u8                      use_sdio_irq:1;
> 
> 1. bool use_sdio_irq;
> 
> 2. supports_sdio_irq is more to the point don't you think?
>      Especially since it activates these two callbacks:
> 
>> +       void (*enable_sdio_irq)(struct mmci_host *host, int enable);
>> +       void (*sdio_irq)(struct mmci_host *host, u32 status);
> 
> Further: all the Ux500 variants support this (bit 22) as well, so enable those
> too in their vendor data. All I have is out-of-band signaling with an GPIO IRQ
> on my Broadcom chips but I think it works (maybe Ulf has tested it in the
> far past).
> 
> Yours,
> Linus Walleij