[PATCH v7 09/10] usb: dwc3: omap: manage "usb_otg_ss_refclk960m" clock

[Roger Quadros]

"usb_otg_ss_refclk960m" is an optional functional clock to the
UBS_OTG_SS module. So manage it in the driver.

Also update device tree binding information.

Signed-off-by: Roger Quadros <rogerq at ti.com>
---
 Documentation/devicetree/bindings/usb/omap-usb.txt |    4 ++++
 drivers/usb/dwc3/dwc3-omap.c                       |   13 +++++++++++++
 2 files changed, 17 insertions(+), 0 deletions(-)

diff --git a/Documentation/devicetree/bindings/usb/omap-usb.txt b/Documentation/devicetree/bindings/usb/omap-usb.txt
index f67573c..47c8530 100644
--- a/Documentation/devicetree/bindings/usb/omap-usb.txt
+++ b/Documentation/devicetree/bindings/usb/omap-usb.txt
@@ -47,6 +47,8 @@ OMAP DWC3 GLUE
  - #address-cells, #size-cells : Must be present if the device has sub-nodes
  - utmi-mode : controls the source of UTMI/PIPE status for VBUS and OTG ID.
    It should be set to "1" for HW mode and "2" for SW mode.
+ - clock : should refer to the clock node that provides 960MHz functional clock.
+ - clock-names : should be "usb_otg_ss_refclk960m"
  - ranges: the child address space are mapped 1:1 onto the parent address space
 
 Optional Properties:
@@ -68,6 +70,8 @@ omap_dwc3 {
 	#address-cells = <1>;
 	#size-cells = <1>;
 	utmi-mode = <2>;
+	clocks = <&usb_otg_ss1_refclk960m>;
+	clock-names = "usb_otg_ss_refclk960m";
 	ranges;
 };
 
diff --git a/drivers/usb/dwc3/dwc3-omap.c b/drivers/usb/dwc3/dwc3-omap.c
index 7f7ea62..c33b26c 100644
--- a/drivers/usb/dwc3/dwc3-omap.c
+++ b/drivers/usb/dwc3/dwc3-omap.c
@@ -32,6 +32,7 @@
 #include <linux/extcon.h>
 #include <linux/extcon/of_extcon.h>
 #include <linux/regulator/consumer.h>
+#include <linux/clk.h>
 
 #include <linux/usb/otg.h>
 
@@ -119,6 +120,8 @@
 #define USBOTGSS_UTMI_OTG_STATUS_SESSVALID	(1 << 2)
 #define USBOTGSS_UTMI_OTG_STATUS_VBUSVALID	(1 << 1)
 
+#define USBOTGSS_REFCLK "usb_otg_ss_refclk960m"
+
 struct dwc3_omap {
 	/* device lock */
 	spinlock_t		lock;
@@ -144,6 +147,7 @@ struct dwc3_omap {
 	struct notifier_block	id_nb;
 
 	struct regulator	*vbus_reg;
+	struct clk		*refclk;
 };
 
 enum omap_dwc3_vbus_id_status {
@@ -449,6 +453,12 @@ static int dwc3_omap_probe(struct platform_device *pdev)
 		}
 	}
 
+	omap->refclk = devm_clk_get(dev, USBOTGSS_REFCLK);
+	if (IS_ERR(omap->refclk)) {
+		dev_err(dev, "couldn't get %s\n", USBOTGSS_REFCLK);
+		return PTR_ERR(omap->refclk);
+	}
+
 	spin_lock_init(&omap->lock);
 
 	omap->dev	= dev;
@@ -464,6 +474,8 @@ static int dwc3_omap_probe(struct platform_device *pdev)
 		goto err0;
 	}
 
+	clk_prepare_enable(omap->refclk);
+
 	reg = dwc3_omap_readl(omap->base, USBOTGSS_REVISION);
 	omap->revision = reg;
 	x_major = USBOTGSS_REVISION_XMAJOR(reg);
@@ -593,6 +605,7 @@ static int dwc3_omap_remove(struct platform_device *pdev)
 		extcon_unregister_interest(&omap->extcon_id_dev);
 	dwc3_omap_disable_irqs(omap);
 	pm_runtime_put_sync(&pdev->dev);
+	clk_disable_unprepare(omap->refclk);
 	pm_runtime_disable(&pdev->dev);
 	device_for_each_child(&pdev->dev, NULL, dwc3_omap_remove_core);
 
-- 
1.7.4.1