Re: [PATCH REPOST v2] mmc: davinci: Add support for set_power callback

[Chris Ball <cjb@laptop.org>]

Hi,

On Thu, Jul 28 2011, Ido Yariv wrote:
> Some devices connected to the MMC bus are power controlled by external
> means. For instance, an SDIO device may be powered down/up by an
> external gpio line.
>
> In order to avoid toggling power from within the MMC host driver, add a
> set_power callback function, which will be called by set_ios upon
> powering down/up.
>
> Signed-off-by: Ido Yariv <ido@wizery.com>

Acked-by: Chris Ball <cjb@laptop.org>

> CC: Chris Ball <cjb@laptop.org>
> ---
>  arch/arm/mach-davinci/include/mach/mmc.h |    3 +++
>  drivers/mmc/host/davinci_mmc.c           |   13 +++++++++++++
>  2 files changed, 16 insertions(+), 0 deletions(-)
>
> diff --git a/arch/arm/mach-davinci/include/mach/mmc.h b/arch/arm/mach-davinci/include/mach/mmc.h
> index d4f1e96..5ba6b22 100644
> --- a/arch/arm/mach-davinci/include/mach/mmc.h
> +++ b/arch/arm/mach-davinci/include/mach/mmc.h
> @@ -12,6 +12,9 @@ struct davinci_mmc_config {
>  	/* get_cd()/get_wp() may sleep */
>  	int	(*get_cd)(int module);
>  	int	(*get_ro)(int module);
> +
> +	void	(*set_power)(int module, bool on);
> +
>  	/* wires == 0 is equivalent to wires == 4 (4-bit parallel) */
>  	u8	wires;
>  
> diff --git a/drivers/mmc/host/davinci_mmc.c b/drivers/mmc/host/davinci_mmc.c
> index 0076c74..64a8325 100644
> --- a/drivers/mmc/host/davinci_mmc.c
> +++ b/drivers/mmc/host/davinci_mmc.c
> @@ -807,12 +807,25 @@ static void calculate_clk_divider(struct mmc_host *mmc, struct mmc_ios *ios)
>  static void mmc_davinci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
>  {
>  	struct mmc_davinci_host *host = mmc_priv(mmc);
> +	struct platform_device *pdev = to_platform_device(mmc->parent);
> +	struct davinci_mmc_config *config = pdev->dev.platform_data;
>  
>  	dev_dbg(mmc_dev(host->mmc),
>  		"clock %dHz busmode %d powermode %d Vdd %04x\n",
>  		ios->clock, ios->bus_mode, ios->power_mode,
>  		ios->vdd);
>  
> +	switch (ios->power_mode) {
> +	case MMC_POWER_OFF:
> +		if (config && config->set_power)
> +			config->set_power(pdev->id, false);
> +		break;
> +	case MMC_POWER_UP:
> +		if (config && config->set_power)
> +			config->set_power(pdev->id, true);
> +		break;
> +	}
> +
>  	switch (ios->bus_width) {
>  	case MMC_BUS_WIDTH_8:
>  		dev_dbg(mmc_dev(host->mmc), "Enabling 8 bit mode\n");

-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child