usb: phy: nop: Manage PHY clock

If the PHY has a clock associated to it then manage the clock.
We just enable the clock in .init() and disable it in .shutdown().

Add clk_rate parameter in platform data and configure the
clock rate during probe if supplied.

Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 53 insertions, 1 deletions

diff --git a/drivers/usb/otg/nop-usb-xceiv.c b/drivers/usb/otg/nop-usb-xceiv.c
index af52870788ec..17c174f18da7 100644
--- a/drivers/usb/otg/nop-usb-xceiv.c
+++ b/drivers/usb/otg/nop-usb-xceiv.c
@@ -32,10 +32,12 @@
 #include <linux/usb/otg.h>
 #include <linux/usb/nop-usb-xceiv.h>
 #include <linux/slab.h>
+#include <linux/clk.h>
 
 struct nop_usb_xceiv {
         struct usb_phy          phy;
         struct device           *dev;
+        struct clk              *clk;
 };
 
 static struct platform_device *pd;
@@ -64,6 +66,24 @@ static int nop_set_suspend(struct usb_phy *x, int suspend)
         return 0;
 }
 
+static int nop_init(struct usb_phy *phy)
+{
+        struct nop_usb_xceiv *nop = dev_get_drvdata(phy->dev);
+
+        if (!IS_ERR(nop->clk))
+                clk_enable(nop->clk);
+
+        return 0;
+}
+
+static void nop_shutdown(struct usb_phy *phy)
+{
+        struct nop_usb_xceiv *nop = dev_get_drvdata(phy->dev);
+
+        if (!IS_ERR(nop->clk))
+                clk_disable(nop->clk);
+}
+
 static int nop_set_peripheral(struct usb_otg *otg, struct usb_gadget *gadget)
 {
         if (!otg)
@@ -112,10 +132,34 @@ static int nop_usb_xceiv_probe(struct platform_device *pdev)
         if (pdata)
                 type = pdata->type;
 
+        nop->clk = devm_clk_get(&pdev->dev, "main_clk");
+        if (IS_ERR(nop->clk)) {
+                dev_dbg(&pdev->dev, "Can't get phy clock: %ld\n",
+                                        PTR_ERR(nop->clk));
+        }
+
+        if (!IS_ERR(nop->clk) && pdata && pdata->clk_rate) {
+                err = clk_set_rate(nop->clk, pdata->clk_rate);
+                if (err) {
+                        dev_err(&pdev->dev, "Error setting clock rate\n");
+                        return err;
+                }
+        }
+
+        if (!IS_ERR(nop->clk)) {
+                err = clk_prepare(nop->clk);
+                if (err) {
+                        dev_err(&pdev->dev, "Error preparing clock\n");
+                        return err;
+                }
+        }
+
         nop->dev                = &pdev->dev;
         nop->phy.dev            = nop->dev;
         nop->phy.label          = "nop-xceiv";
         nop->phy.set_suspend    = nop_set_suspend;
+        nop->phy.init           = nop_init;
+        nop->phy.shutdown       = nop_shutdown;
         nop->phy.state          = OTG_STATE_UNDEFINED;
 
         nop->phy.otg->phy               = &nop->phy;
@@ -126,7 +170,7 @@ static int nop_usb_xceiv_probe(struct platform_device *pdev)
         if (err) {
                 dev_err(&pdev->dev, "can't register transceiver, err: %d\n",
                         err);
-                return err;
+                goto err_add;
         }
 
         platform_set_drvdata(pdev, nop);
@@ -134,12 +178,20 @@ static int nop_usb_xceiv_probe(struct platform_device *pdev)
         ATOMIC_INIT_NOTIFIER_HEAD(&nop->phy.notifier);
 
         return 0;
+
+err_add:
+        if (!IS_ERR(nop->clk))
+                clk_unprepare(nop->clk);
+        return err;
 }
 
 static int nop_usb_xceiv_remove(struct platform_device *pdev)
 {
         struct nop_usb_xceiv *nop = platform_get_drvdata(pdev);
 
+        if (!IS_ERR(nop->clk))
+                clk_unprepare(nop->clk);
+
         usb_remove_phy(&nop->phy);
 
         platform_set_drvdata(pdev, NULL);