Re: [PATCH v2 06/13] hw/sd/sd: Remove legacy sd_set_cb() in favor of GPIOs

[Bernhard Beschow <shentey@gmail.com>]

Am 27. Januar 2025 13:24:46 UTC schrieb Peter Maydell <peter.maydell@linaro.org>:
>On Sat, 11 Jan 2025 at 18:37, Bernhard Beschow <shentey@gmail.com> wrote:
>>
>> Commit ce5dd27534b0 "hw/sd: Remove omap2_mmc device" removed the last user of
>> sd_set_cb(). Rework this functionality into GPIOs.
>>
>> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
>> Signed-off-by: Bernhard Beschow <shentey@gmail.com>
>
>What is this for? We have a non-legacy API for "the SD controller
>needs to know when the SD card is inserted or the readonly
>status changes", which is that the controller implements the
>SDBasClass set_inserted and set_readonly methods. (See the pl011
>for an example.)
>
>I would prefer it if we used that consistently, rather than having
>two mechanisms, one using GPIO lines and one using class methods.
>I think we should delete the sd_set_cb() API and handling code
>entirely.

According to the Linux MMC controller DT schema, there are actually two ways to implement cd and wp lines [1]. When implementing the imx8mp-evk board, I thought I would need to model the GPIO style [2], hence I implemented it plus the active low part on the SD card. Later I noticed that the card gets detected anyway without the GPIO wiring, so I'm fine if the code gets removed instead.

Best regards,
Bernhard

[1] <https://github.com/torvalds/linux/blob/v6.13/Documentation/devicetree/bindings/mmc/mmc-controller.yaml#L60>
[2] <https://github.com/torvalds/linux/blob/v6.13/arch/arm64/boot/dts/freescale/imx8mp-evk.dts#L776>

>
>thanks
>-- PMM