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

[Fabien Parent]

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>
---
 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;
 
 	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);
-- 
2.20.1