[PATCH 3/8] usb: phy: nop: Manage PHY clock

[Roger Quadros]

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 <rog...@ti.com>
Acked-by: Felipe Balbi <ba...@ti.com>
---
 drivers/usb/otg/nop-usb-xceiv.c |   54 ++++++++++++++++++++++++++++++++++++++-
 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 af52870..17c174f 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);
-- 
1.7.4.1

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