[PATCH v2 2/2] usb: dwc2: add multiple clocks handling

[Frank Wang]

Since dwc2 may have one or more input clocks need to manage for some
platform, so this adds change clk to clk's array of struct dwc2_hsotg
to handle more clocks operation.

Signed-off-by: Frank Wang <frank.wang@xxxxxxxxxxxxxx>
---
 drivers/usb/dwc2/core.h     |  5 ++++-
 drivers/usb/dwc2/platform.c | 39 ++++++++++++++++++++++++++-------------
 2 files changed, 30 insertions(+), 14 deletions(-)

diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h
index 1a7e830..afde8a1 100644
--- a/drivers/usb/dwc2/core.h
+++ b/drivers/usb/dwc2/core.h
@@ -121,6 +121,9 @@ static inline void dwc2_writel(u32 value, void __iomem *addr)
 /* Maximum number of Endpoints/HostChannels */
 #define MAX_EPS_CHANNELS	16
 
+/* Maximum number of dwc2 input clocks */
+#define DWC2_MAX_CLKS	5
+
 /* dwc2-hsotg declarations */
 static const char * const dwc2_hsotg_supply_names[] = {
 	"vusb_d",               /* digital USB supply, 1.2V */
@@ -913,7 +916,7 @@ struct dwc2_hsotg {
 	spinlock_t lock;
 	void *priv;
 	int     irq;
-	struct clk *clk;
+	struct clk *clks[DWC2_MAX_CLKS];
 	struct reset_control *reset;
 
 	unsigned int queuing_high_bandwidth:1;
diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c
index 9564bc7..795fc43b 100644
--- a/drivers/usb/dwc2/platform.c
+++ b/drivers/usb/dwc2/platform.c
@@ -123,17 +123,20 @@ static int dwc2_get_dr_mode(struct dwc2_hsotg *hsotg)
 static int __dwc2_lowlevel_hw_enable(struct dwc2_hsotg *hsotg)
 {
 	struct platform_device *pdev = to_platform_device(hsotg->dev);
-	int ret;
+	int clk, ret;
 
 	ret = regulator_bulk_enable(ARRAY_SIZE(hsotg->supplies),
 				    hsotg->supplies);
 	if (ret)
 		return ret;
 
-	if (hsotg->clk) {
-		ret = clk_prepare_enable(hsotg->clk);
-		if (ret)
+	for (clk = 0; clk < DWC2_MAX_CLKS && hsotg->clks[clk]; clk++) {
+		ret = clk_prepare_enable(hsotg->clks[clk]);
+		if (ret) {
+			while (--clk >= 0)
+				clk_disable_unprepare(hsotg->clks[clk]);
 			return ret;
+		}
 	}
 
 	if (hsotg->uphy) {
@@ -168,7 +171,7 @@ int dwc2_lowlevel_hw_enable(struct dwc2_hsotg *hsotg)
 static int __dwc2_lowlevel_hw_disable(struct dwc2_hsotg *hsotg)
 {
 	struct platform_device *pdev = to_platform_device(hsotg->dev);
-	int ret = 0;
+	int clk, ret = 0;
 
 	if (hsotg->uphy) {
 		usb_phy_shutdown(hsotg->uphy);
@@ -182,8 +185,9 @@ static int __dwc2_lowlevel_hw_disable(struct dwc2_hsotg *hsotg)
 	if (ret)
 		return ret;
 
-	if (hsotg->clk)
-		clk_disable_unprepare(hsotg->clk);
+	for (clk = DWC2_MAX_CLKS - 1; clk >= 0; clk--)
+		if (hsotg->clks[clk])
+			clk_disable_unprepare(hsotg->clks[clk]);
 
 	ret = regulator_bulk_disable(ARRAY_SIZE(hsotg->supplies),
 				     hsotg->supplies);
@@ -209,7 +213,7 @@ int dwc2_lowlevel_hw_disable(struct dwc2_hsotg *hsotg)
 
 static int dwc2_lowlevel_hw_init(struct dwc2_hsotg *hsotg)
 {
-	int i, ret;
+	int i, clk, ret;
 
 	hsotg->reset = devm_reset_control_get_optional(hsotg->dev, "dwc2");
 	if (IS_ERR(hsotg->reset)) {
@@ -282,11 +286,20 @@ static int dwc2_lowlevel_hw_init(struct dwc2_hsotg *hsotg)
 			hsotg->phyif = GUSBCFG_PHYIF8;
 	}
 
-	/* Clock */
-	hsotg->clk = devm_clk_get(hsotg->dev, "otg");
-	if (IS_ERR(hsotg->clk)) {
-		hsotg->clk = NULL;
-		dev_dbg(hsotg->dev, "cannot get otg clock\n");
+	/* Clocks */
+	for (clk = 0; clk < DWC2_MAX_CLKS; clk++) {
+		hsotg->clks[clk] = of_clk_get(hsotg->dev->of_node, clk);
+		if (IS_ERR(hsotg->clks[clk])) {
+			ret = PTR_ERR(hsotg->clks[clk]);
+			if (ret == -EPROBE_DEFER) {
+				while (--clk >= 0)
+					clk_put(hsotg->clks[clk]);
+				return ret;
+			}
+
+			hsotg->clks[clk] = NULL;
+			break;
+		}
 	}
 
 	/* Regulators */
-- 
1.9.1