[U-Boot] [PATCH 1/6] mmc: mtk-sd: add source_cg clock support

[Ryder Lee]

On Mon, 2019-02-04 at 11:58 +0100, Fabien Parent wrote:
> Some MediaTek SoC need an additional clock "source_cg". Enable
> this new clock. We reuse the same clock name as in the kernel.
> 
> Signed-off-by: Fabien Parent <fparent at baylibre.com>

Acked-by: Ryder Lee <ryder.lee at mediatek.com>

> ---
>  drivers/mmc/mtk-sd.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/drivers/mmc/mtk-sd.c b/drivers/mmc/mtk-sd.c
> index d3f0778368..8573ea7430 100644
> --- a/drivers/mmc/mtk-sd.c
> +++ b/drivers/mmc/mtk-sd.c
> @@ -247,7 +247,9 @@ struct msdc_host {
>  	struct msdc_compatible *dev_comp;
>  
>  	struct clk src_clk;	/* for SD/MMC bus clock */
> +	struct clk src_clk_cg;	/* optional, MSDC source clock control gate */
>  	struct clk h_clk;	/* MSDC core clock */
> +	bool has_src_clk_cg;

<just_checking>
  Could we have a chance to get rid of this flag?
</just_checking>

>  	u32 src_clk_freq;	/* source clock */
>  	u32 mclk;		/* mmc framework required bus clock */
> @@ -1269,6 +1271,8 @@ static void msdc_ungate_clock(struct msdc_host *host)
>  {
>  	clk_enable(&host->src_clk);
>  	clk_enable(&host->h_clk);
> +	if (host->has_src_clk_cg)
> +		clk_enable(&host->src_clk_cg);
>  }
>  
>  static int msdc_drv_probe(struct udevice *dev)
> @@ -1332,6 +1336,10 @@ static int msdc_ofdata_to_platdata(struct udevice *dev)
>  	if (ret < 0)
>  		return ret;
>  
> +	ret = clk_get_by_name(dev, "source_cg", &host->src_clk_cg); /* optional */
> +	if (!ret)
> +		host->has_src_clk_cg = true;
> +
>  #if IS_ENABLED(DM_GPIO)
>  	gpio_request_by_name(dev, "wp-gpios", 0, &host->gpio_wp, GPIOD_IS_IN);
>  	gpio_request_by_name(dev, "cd-gpios", 0, &host->gpio_cd, GPIOD_IS_IN);