USB: ehci-spear: Add PM support
This patch adds support for standby/S2R/hibernate for ehci-spear driver.
Signed-off-by: Deepak Sikri <deepak.sikri@st.com>
Signed-off-by: Pratyush Anand <pratyush.anand@st.com>
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/host/ehci-spear.c b/drivers/usb/host/ehci-spear.c
index b115b0b..6e92855 100644
--- a/drivers/usb/host/ehci-spear.c
+++ b/drivers/usb/host/ehci-spear.c
@@ -11,8 +11,10 @@
* more details.
*/
-#include <linux/platform_device.h>
#include <linux/clk.h>
+#include <linux/jiffies.h>
+#include <linux/platform_device.h>
+#include <linux/pm.h>
struct spear_ehci {
struct ehci_hcd ehci;
@@ -90,6 +92,82 @@
.clear_tt_buffer_complete = ehci_clear_tt_buffer_complete,
};
+#ifdef CONFIG_PM
+static int ehci_spear_drv_suspend(struct device *dev)
+{
+ struct usb_hcd *hcd = dev_get_drvdata(dev);
+ struct ehci_hcd *ehci = hcd_to_ehci(hcd);
+ unsigned long flags;
+ int rc = 0;
+
+ if (time_before(jiffies, ehci->next_statechange))
+ msleep(10);
+
+ /*
+ * 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.
+ */
+ spin_lock_irqsave(&ehci->lock, flags);
+ ehci_prepare_ports_for_controller_suspend(ehci, device_may_wakeup(dev));
+ ehci_writel(ehci, 0, &ehci->regs->intr_enable);
+ ehci_readl(ehci, &ehci->regs->intr_enable);
+ spin_unlock_irqrestore(&ehci->lock, flags);
+
+ return rc;
+}
+
+static int ehci_spear_drv_resume(struct device *dev)
+{
+ struct usb_hcd *hcd = dev_get_drvdata(dev);
+ struct ehci_hcd *ehci = hcd_to_ehci(hcd);
+
+ if (time_before(jiffies, ehci->next_statechange))
+ msleep(100);
+
+ 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);
+
+ /*
+ * Else reset, to cope with power loss or flush-to-storage style
+ * "resume" having let BIOS kick in during reboot.
+ */
+ ehci_halt(ehci);
+ 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);
+ return 0;
+}
+#endif /* CONFIG_PM */
+
+static SIMPLE_DEV_PM_OPS(ehci_spear_pm_ops, ehci_spear_drv_suspend,
+ ehci_spear_drv_resume);
+
static int spear_ehci_hcd_drv_probe(struct platform_device *pdev)
{
struct usb_hcd *hcd ;
@@ -205,7 +283,8 @@
.shutdown = usb_hcd_platform_shutdown,
.driver = {
.name = "spear-ehci",
- .bus = &platform_bus_type
+ .bus = &platform_bus_type,
+ .pm = &ehci_spear_pm_ops,
}
};