Re: [PATCH v2] mmc: sh_mobile_sdhi: support modular mmc-core with non-standard hotplug

[Chris Ball <cjb@laptop.org>]

Hi Guennadi,

On Fri, Mar 09 2012, Guennadi Liakhovetski wrote:
> Currently if a platform wants to implement a non-standard card-detection
> method, it would need to call tmio_mmc_cd_wakeup(), which is an inline
> function, calling mmc_detect_change(). For this the platform would have
> to link mmc_core statically into the kernel, losing the ability to build
> it as a module. This patch adds a callback to the sh_mobile_sdhi driver,
> which eliminates this dependency.
>
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
> ---
>
> v2:
>
> 1. remove a call to tmio_mmc_cd_wakeup(), call mmc_detect_change() 
>    directly instead
> 2. document the new struct sh_mobile_sdhi_ops
>
>  drivers/mmc/host/sh_mobile_sdhi.c  |   11 ++++++++++-
>  include/linux/mmc/sh_mobile_sdhi.h |   11 ++++++++++-
>  2 files changed, 20 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mmc/host/sh_mobile_sdhi.c b/drivers/mmc/host/sh_mobile_sdhi.c
> index dd288d6..8352054 100644
> --- a/drivers/mmc/host/sh_mobile_sdhi.c
> +++ b/drivers/mmc/host/sh_mobile_sdhi.c
> @@ -100,6 +100,15 @@ static int sh_mobile_sdhi_write16_hook(struct tmio_mmc_host *host, int addr)
>  	return 0;
>  }
>  
> +static void sh_mobile_sdhi_cd_wakeup(const struct platform_device *pdev)
> +{
> +	mmc_detect_change(dev_get_drvdata(&pdev->dev), msecs_to_jiffies(100));
> +}
> +
> +static const struct sh_mobile_sdhi_ops sdhi_ops = {
> +	.cd_wakeup = sh_mobile_sdhi_cd_wakeup,
> +};
> +
>  static int __devinit sh_mobile_sdhi_probe(struct platform_device *pdev)
>  {
>  	struct sh_mobile_sdhi *priv;
> @@ -121,7 +130,7 @@ static int __devinit sh_mobile_sdhi_probe(struct platform_device *pdev)
>  	p->pdata = mmc_data;
>  
>  	if (p->init) {
> -		ret = p->init(pdev);
> +		ret = p->init(pdev, &sdhi_ops);
>  		if (ret)
>  			goto einit;
>  	}

This patch doesn't apply because the "if (p->init)" conditional isn't in
mmc-next.  Maybe you're depending on a patch that I haven't taken yet?

> diff --git a/include/linux/mmc/sh_mobile_sdhi.h b/include/linux/mmc/sh_mobile_sdhi.h
> index 686b85b..e94e620 100644
> --- a/include/linux/mmc/sh_mobile_sdhi.h
> +++ b/include/linux/mmc/sh_mobile_sdhi.h
> @@ -10,6 +10,14 @@ struct tmio_mmc_data;
>  #define SH_MOBILE_SDHI_IRQ_SDCARD	"sdcard"
>  #define SH_MOBILE_SDHI_IRQ_SDIO		"sdio"
>  
> +/**
> + * struct sh_mobile_sdhi_ops - SDHI driver callbacks
> + * @cd_wakeup:		trigger a card-detection run
> + */
> +struct sh_mobile_sdhi_ops {
> +	void (*cd_wakeup)(const struct platform_device *pdev);
> +};
> +
>  struct sh_mobile_sdhi_info {
>  	int dma_slave_tx;
>  	int dma_slave_rx;
> @@ -22,7 +30,8 @@ struct sh_mobile_sdhi_info {
>  	int (*get_cd)(struct platform_device *pdev);
>  
>  	/* callbacks for board specific setup code */
> -	int (*init)(struct platform_device *pdev);
> +	int (*init)(struct platform_device *pdev,
> +		    const struct sh_mobile_sdhi_ops *ops);
>  	void (*cleanup)(struct platform_device *pdev);
>  };

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