[PATCH 4/4] MXS-MMC: Add wp-inverted property

[Lothar Waßmann]

Hi,

Marek Vasut writes:
> The write-protect GPIO is inverted on some boards. Handle such case.
> 
> Signed-off-by: Marek Vasut <marex at denx.de>
> Cc: Shawn Guo <shawn.guo at linaro.org>
> Cc: Fabio Estevam <fabio.estevam at freescale.com>
> ---
>  Documentation/devicetree/bindings/mmc/mxs-mmc.txt |    1 +
>  drivers/mmc/host/mxs-mmc.c                        |   11 ++++++++++-
>  2 files changed, 11 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/devicetree/bindings/mmc/mxs-mmc.txt b/Documentation/devicetree/bindings/mmc/mxs-mmc.txt
> index 14d870a..0a7d2cd 100644
> --- a/Documentation/devicetree/bindings/mmc/mxs-mmc.txt
> +++ b/Documentation/devicetree/bindings/mmc/mxs-mmc.txt
> @@ -13,6 +13,7 @@ Required properties:
>  
>  Optional properties:
>  - wp-gpios: Specify GPIOs for write protection
> +- wp-inverted: Set if the write protection GPIO is inverted
>  
>  Examples:
>  
> diff --git a/drivers/mmc/host/mxs-mmc.c b/drivers/mmc/host/mxs-mmc.c
> index 277161d..119beb9 100644
> --- a/drivers/mmc/host/mxs-mmc.c
> +++ b/drivers/mmc/host/mxs-mmc.c
> @@ -164,16 +164,23 @@ struct mxs_mmc_host {
>  	spinlock_t			lock;
>  	int				sdio_irq_en;
>  	int				wp_gpio;
> +	int				wp_inverted:1;
>  };
>  
>  static int mxs_mmc_get_ro(struct mmc_host *mmc)
>  {
>  	struct mxs_mmc_host *host = mmc_priv(mmc);
> +	int ret;
>  
>  	if (!gpio_is_valid(host->wp_gpio))
>  		return -EINVAL;
>  
> -	return gpio_get_value(host->wp_gpio);
> +	ret = gpio_get_value(host->wp_gpio);
> +
> +	if (host->wp_inverted)
> +		ret = !ret;
> +
> +	return ret;
>  }
>  
>  static int mxs_mmc_get_cd(struct mmc_host *mmc)
> @@ -786,6 +793,8 @@ static int mxs_mmc_probe(struct platform_device *pdev)
>  		else if (bus_width == 8)
>  			mmc->caps |= MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA;
>  		host->wp_gpio = of_get_named_gpio(np, "wp-gpios", 0);
> +		if (of_find_property(np, "wp-inverted", NULL))
> +			host->wp_inverted = 1;
>
Why not simply specify the GPIO in question as being active-low in the
GPIO definition and use of_get_named_gpio_flags()?


Lothar Waßmann
-- 
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