USB: ehci-s5p: add PM support

This patch adds power management support such as suspend and resume
functions.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 95 insertions, 0 deletions

diff --git a/drivers/usb/host/ehci-s5p.c b/drivers/usb/host/ehci-s5p.c
index e3374c8f7b3..b3958b3d316 100644
--- a/drivers/usb/host/ehci-s5p.c
+++ b/drivers/usb/host/ehci-s5p.c
@@ -189,6 +189,100 @@ static void s5p_ehci_shutdown(struct platform_device *pdev)
                 hcd->driver->shutdown(hcd);
 }
 
+#ifdef CONFIG_PM
+static int s5p_ehci_suspend(struct device *dev)
+{
+        struct s5p_ehci_hcd *s5p_ehci = dev_get_drvdata(dev);
+        struct usb_hcd *hcd = s5p_ehci->hcd;
+        struct ehci_hcd *ehci = hcd_to_ehci(hcd);
+        struct platform_device *pdev = to_platform_device(dev);
+        struct s5p_ehci_platdata *pdata = pdev->dev.platform_data;
+        unsigned long flags;
+        int rc = 0;
+
+        if (time_before(jiffies, ehci->next_statechange))
+                msleep(20);
+
+        /*
+         * Root hub was already suspended. Disable irq emission and
+         * mark HW unaccessible.  The PM and USB cores make sure that
+         * the root hub is either suspended or stopped.
+         */
+        ehci_prepare_ports_for_controller_suspend(ehci, device_may_wakeup(dev));
+        spin_lock_irqsave(&ehci->lock, flags);
+        ehci_writel(ehci, 0, &ehci->regs->intr_enable);
+        (void)ehci_readl(ehci, &ehci->regs->intr_enable);
+
+        clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
+        spin_unlock_irqrestore(&ehci->lock, flags);
+
+        if (pdata && pdata->phy_exit)
+                pdata->phy_exit(pdev, S5P_USB_PHY_HOST);
+
+        return rc;
+}
+
+static int s5p_ehci_resume(struct device *dev)
+{
+        struct s5p_ehci_hcd *s5p_ehci = dev_get_drvdata(dev);
+        struct usb_hcd *hcd = s5p_ehci->hcd;
+        struct ehci_hcd *ehci = hcd_to_ehci(hcd);
+        struct platform_device *pdev = to_platform_device(dev);
+        struct s5p_ehci_platdata *pdata = pdev->dev.platform_data;
+
+        if (pdata && pdata->phy_init)
+                pdata->phy_init(pdev, S5P_USB_PHY_HOST);
+
+        if (time_before(jiffies, ehci->next_statechange))
+                msleep(100);
+
+        /* Mark hardware accessible again as we are out of D3 state by now */
+        set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
+
+        if (ehci_readl(ehci, &ehci->regs->configured_flag) == FLAG_CF) {
+                int     mask = INTR_MASK;
+
+                ehci_prepare_ports_for_controller_resume(ehci);
+                if (!hcd->self.root_hub->do_remote_wakeup)
+                        mask &= ~STS_PCD;
+                ehci_writel(ehci, mask, &ehci->regs->intr_enable);
+                ehci_readl(ehci, &ehci->regs->intr_enable);
+                return 0;
+        }
+
+        usb_root_hub_lost_power(hcd->self.root_hub);
+
+        (void) ehci_halt(ehci);
+        (void) ehci_reset(ehci);
+
+        /* emptying the schedule aborts any urbs */
+        spin_lock_irq(&ehci->lock);
+        if (ehci->reclaim)
+                end_unlink_async(ehci);
+        ehci_work(ehci);
+        spin_unlock_irq(&ehci->lock);
+
+        ehci_writel(ehci, ehci->command, &ehci->regs->command);
+        ehci_writel(ehci, FLAG_CF, &ehci->regs->configured_flag);
+        ehci_readl(ehci, &ehci->regs->command); /* unblock posted writes */
+
+        /* here we "know" root ports should always stay powered */
+        ehci_port_power(ehci, 1);
+
+        hcd->state = HC_STATE_SUSPENDED;
+
+        return 0;
+}
+#else
+#define s5p_ehci_suspend        NULL
+#define s5p_ehci_resume         NULL
+#endif
+
+static const struct dev_pm_ops s5p_ehci_pm_ops = {
+        .suspend        = s5p_ehci_suspend,
+        .resume         = s5p_ehci_resume,
+};
+
 static struct platform_driver s5p_ehci_driver = {
         .probe          = s5p_ehci_probe,
         .remove         = __devexit_p(s5p_ehci_remove),
@@ -196,6 +290,7 @@ static struct platform_driver s5p_ehci_driver = {
         .driver = {
                 .name   = "s5p-ehci",
                 .owner  = THIS_MODULE,
+                .pm     = &s5p_ehci_pm_ops,
         }
 };