usb: gadget: s3c-hsotg: add proper suspend/resume support

This patch adds suspend/resume support to s3c-hsotg driver. It makes UDC
driver more power efficient.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Robert Baldyga <r.baldyga@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 49 insertions, 4 deletions

diff --git a/drivers/usb/gadget/s3c-hsotg.c b/drivers/usb/gadget/s3c-hsotg.c
index 99c8e3ca6a3c..2a9cb674926a 100644
--- a/drivers/usb/gadget/s3c-hsotg.c
+++ b/drivers/usb/gadget/s3c-hsotg.c
@@ -3774,10 +3774,55 @@ static int s3c_hsotg_remove(struct platform_device *pdev)
         return 0;
 }
 
-#if 1
-#define s3c_hsotg_suspend NULL
-#define s3c_hsotg_resume NULL
-#endif
+static int s3c_hsotg_suspend(struct platform_device *pdev, pm_message_t state)
+{
+        struct s3c_hsotg *hsotg = platform_get_drvdata(pdev);
+        unsigned long flags;
+        int ret = 0;
+
+        if (hsotg->driver)
+                dev_info(hsotg->dev, "suspending usb gadget %s\n",
+                         hsotg->driver->driver.name);
+
+        spin_lock_irqsave(&hsotg->lock, flags);
+        s3c_hsotg_disconnect(hsotg);
+        s3c_hsotg_phy_disable(hsotg);
+        hsotg->gadget.speed = USB_SPEED_UNKNOWN;
+        spin_unlock_irqrestore(&hsotg->lock, flags);
+
+        if (hsotg->driver) {
+                int ep;
+                for (ep = 0; ep < hsotg->num_of_eps; ep++)
+                        s3c_hsotg_ep_disable(&hsotg->eps[ep].ep);
+
+                ret = regulator_bulk_disable(ARRAY_SIZE(hsotg->supplies),
+                                             hsotg->supplies);
+        }
+
+        return ret;
+}
+
+static int s3c_hsotg_resume(struct platform_device *pdev)
+{
+        struct s3c_hsotg *hsotg = platform_get_drvdata(pdev);
+        unsigned long flags;
+        int ret = 0;
+
+        if (hsotg->driver) {
+                dev_info(hsotg->dev, "resuming usb gadget %s\n",
+                         hsotg->driver->driver.name);
+                ret = regulator_bulk_enable(ARRAY_SIZE(hsotg->supplies),
+                                      hsotg->supplies);
+        }
+
+        spin_lock_irqsave(&hsotg->lock, flags);
+        hsotg->last_rst = jiffies;
+        s3c_hsotg_phy_enable(hsotg);
+        s3c_hsotg_core_init(hsotg);
+        spin_unlock_irqrestore(&hsotg->lock, flags);
+
+        return ret;
+}
 
 #ifdef CONFIG_OF
 static const struct of_device_id s3c_hsotg_of_ids[] = {