[PATCH V4 1/4] mmc: core: Initial support for MMC power sequences

[Javier Martinez Canillas]

Hello Ulf,

On Mon, Jan 19, 2015 at 10:13 AM, Ulf Hansson <ulf.hansson at linaro.org> wrote:
> System on chip designs may specify a specific MMC power sequence. To
> successfully detect an (e)MMC/SD/SDIO card, that power sequence must
> be followed while initializing the card.
>
> To be able to handle these SOC specific power sequences, let's add a
> MMC power sequence interface. It provides the following functions to
> help the mmc core to deal with these power sequences.
>
> mmc_pwrseq_alloc() - Invoked from mmc_of_parse(), to initialize data.
> mmc_pwrseq_pre_power_on()- Invoked in the beginning of mmc_power_up().
> mmc_pwrseq_post_power_on()- Invoked at the end in mmc_power_up().
> mmc_pwrseq_power_off()- Invoked from mmc_power_off().
> mmc_pwrseq_free() - Invoked from mmc_free_host(), to free data.
>
> Each MMC power sequence provider will be responsible to implement a set
> of callbacks. These callbacks mirrors the functions above.
>
> This patch adds the skeleton, following patches will extend the core of
> the MMC power sequence and add support for a specific simple MMC power
> sequence.
>
> Do note, since the mmc_pwrseq_alloc() is invoked from mmc_of_parse(),
> host drivers needs to make use of this API to enable the support for
> MMC power sequences. Moreover the MMC power sequence support depends on
> CONFIG_OF.
>
> Signed-off-by: Ulf Hansson <ulf.hansson at linaro.org>
> ---

Patch looks good to me and I could successfully get the SDIO wlan chip
in the Snow Chromebook after extending the pwrseq_simple driver so on
Exynos5250 Snow Chromebook:

Tested-by: Javier Martinez Canillas <javier.martinez at collabora.co.uk>
Reviewed-by: Javier Martinez Canillas <javier.martinez at collabora.co.uk>

Best regards,
Javier