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

From: Roger Quadros
Date: Tue Mar 12 2013 - 07:25:46 EST


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@xxxxxx>
Acked-by: Felipe Balbi <balbi@xxxxxx>
---
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

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/