[PATCH v7 4/4] mmc: mediatek: Add subsys clock control for MT8192 msdc

[Wenbin Mei]

MT8192 msdc is an independent sub system, we need control more bus
clocks for it.
Add support for the additional subsys clocks to allow it to be
configured appropriately.

Signed-off-by: Wenbin Mei <wenbin.mei at mediatek.com>
Reviewed-by: Nicolas Boichat <drinkcat at chromium.org>
---
 drivers/mmc/host/mtk-sd.c | 74 +++++++++++++++++++++++++++++----------
 1 file changed, 56 insertions(+), 18 deletions(-)

diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
index a704745e5882..c7df7510f120 100644
--- a/drivers/mmc/host/mtk-sd.c
+++ b/drivers/mmc/host/mtk-sd.c
@@ -35,6 +35,7 @@
 #include "cqhci.h"
 
 #define MAX_BD_NUM          1024
+#define MSDC_NR_CLOCKS      3
 
 /*--------------------------------------------------------------------------*/
 /* Common Definition                                                        */
@@ -425,6 +426,8 @@ struct msdc_host {
 	struct clk *h_clk;      /* msdc h_clk */
 	struct clk *bus_clk;	/* bus clock which used to access register */
 	struct clk *src_clk_cg; /* msdc source clock control gate */
+	struct clk *sys_clk_cg;	/* msdc subsys clock control gate */
+	struct clk_bulk_data bulk_clks[MSDC_NR_CLOCKS];
 	u32 mclk;		/* mmc subsystem clock frequency */
 	u32 src_clk_freq;	/* source clock frequency */
 	unsigned char timing;
@@ -784,6 +787,7 @@ static void msdc_set_busy_timeout(struct msdc_host *host, u64 ns, u64 clks)
 
 static void msdc_gate_clock(struct msdc_host *host)
 {
+	clk_bulk_disable_unprepare(MSDC_NR_CLOCKS, host->bulk_clks);
 	clk_disable_unprepare(host->src_clk_cg);
 	clk_disable_unprepare(host->src_clk);
 	clk_disable_unprepare(host->bus_clk);
@@ -792,10 +796,18 @@ static void msdc_gate_clock(struct msdc_host *host)
 
 static void msdc_ungate_clock(struct msdc_host *host)
 {
+	int ret;
+
 	clk_prepare_enable(host->h_clk);
 	clk_prepare_enable(host->bus_clk);
 	clk_prepare_enable(host->src_clk);
 	clk_prepare_enable(host->src_clk_cg);
+	ret = clk_bulk_prepare_enable(MSDC_NR_CLOCKS, host->bulk_clks);
+	if (ret) {
+		dev_err(host->dev, "Cannot enable pclk/axi/ahb clock gates\n");
+		return;
+	}
+
 	while (!(readl(host->base + MSDC_CFG) & MSDC_CFG_CKSTB))
 		cpu_relax();
 }
@@ -2366,6 +2378,48 @@ static void msdc_of_property_parse(struct platform_device *pdev,
 		host->cqhci = false;
 }
 
+static int msdc_of_clock_parse(struct platform_device *pdev,
+			       struct msdc_host *host)
+{
+	int ret;
+
+	host->src_clk = devm_clk_get(&pdev->dev, "source");
+	if (IS_ERR(host->src_clk))
+		return PTR_ERR(host->src_clk);
+
+	host->h_clk = devm_clk_get(&pdev->dev, "hclk");
+	if (IS_ERR(host->h_clk))
+		return PTR_ERR(host->h_clk);
+
+	host->bus_clk = devm_clk_get_optional(&pdev->dev, "bus_clk");
+	if (IS_ERR(host->bus_clk))
+		host->bus_clk = NULL;
+
+	/*source clock control gate is optional clock*/
+	host->src_clk_cg = devm_clk_get_optional(&pdev->dev, "source_cg");
+	if (IS_ERR(host->src_clk_cg))
+		host->src_clk_cg = NULL;
+
+	host->sys_clk_cg = devm_clk_get_optional(&pdev->dev, "sys_cg");
+	if (IS_ERR(host->sys_clk_cg))
+		host->sys_clk_cg = NULL;
+
+	/* If present, always enable for this clock gate */
+	clk_prepare_enable(host->sys_clk_cg);
+
+	host->bulk_clks[0].id = "pclk_cg";
+	host->bulk_clks[1].id = "axi_cg";
+	host->bulk_clks[2].id = "ahb_cg";
+	ret = devm_clk_bulk_get_optional(&pdev->dev, MSDC_NR_CLOCKS,
+					 host->bulk_clks);
+	if (ret) {
+		dev_err(&pdev->dev, "Cannot get pclk/axi/ahb clock gates\n");
+		return ret;
+	}
+
+	return 0;
+}
+
 static int msdc_drv_probe(struct platform_device *pdev)
 {
 	struct mmc_host *mmc;
@@ -2405,25 +2459,9 @@ static int msdc_drv_probe(struct platform_device *pdev)
 	if (ret)
 		goto host_free;
 
-	host->src_clk = devm_clk_get(&pdev->dev, "source");
-	if (IS_ERR(host->src_clk)) {
-		ret = PTR_ERR(host->src_clk);
-		goto host_free;
-	}
-
-	host->h_clk = devm_clk_get(&pdev->dev, "hclk");
-	if (IS_ERR(host->h_clk)) {
-		ret = PTR_ERR(host->h_clk);
+	ret = msdc_of_clock_parse(pdev, host);
+	if (ret)
 		goto host_free;
-	}
-
-	host->bus_clk = devm_clk_get(&pdev->dev, "bus_clk");
-	if (IS_ERR(host->bus_clk))
-		host->bus_clk = NULL;
-	/*source clock control gate is optional clock*/
-	host->src_clk_cg = devm_clk_get(&pdev->dev, "source_cg");
-	if (IS_ERR(host->src_clk_cg))
-		host->src_clk_cg = NULL;
 
 	host->reset = devm_reset_control_get_optional_exclusive(&pdev->dev,
 								"hrst");
-- 
2.18.0