From: Thierry Reding <treding@xxxxxxxxxx>
This implements basic engine-level powergate support which allows the
XUSB controller to be put into a low power mode on system sleep and get
it out of that low power mode again on resume.
Based on work by JC Kuo <jckuo@xxxxxxxxxx>.
Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
---
Changes in v2:
- remove useless gotos
---
drivers/usb/host/xhci-tegra.c | 127 +++++++++++++++++++++++++++++++---
1 file changed, 119 insertions(+), 8 deletions(-)
diff --git a/drivers/usb/host/xhci-tegra.c b/drivers/usb/host/xhci-tegra.c
index 7f6657ad5ce5..0b58ef3a7f7f 100644
--- a/drivers/usb/host/xhci-tegra.c
+++ b/drivers/usb/host/xhci-tegra.c
@@ -1447,6 +1447,45 @@ static int tegra_xusb_remove(struct platform_device *pdev)
}
#ifdef CONFIG_PM_SLEEP
+static bool xhci_hub_ports_suspended(struct xhci_hub *hub)
+{
+ struct device *dev = hub->hcd->self.controller;
+ bool status = true;
+ unsigned int i;
+ u32 value;
+
+ for (i = 0; i < hub->num_ports; i++) {
+ value = readl(hub->ports[i]->addr);
+ if ((value & PORT_PE) == 0)
+ continue;
+
+ if ((value & PORT_PLS_MASK) != XDEV_U3) {
+ dev_info(dev, "%u-%u isn't suspended: %#010x\n",
+ hub->hcd->self.busnum, i + 1, value);
+ status = false;
+ }
+ }
+
+ return status;
+}
+
+static int tegra_xusb_check_ports(struct tegra_xusb *tegra)
+{
+ struct xhci_hcd *xhci = hcd_to_xhci(tegra->hcd);
+ unsigned long flags;
+ int err = 0;
+
+ spin_lock_irqsave(&xhci->lock, flags);
+
+ if (!xhci_hub_ports_suspended(&xhci->usb2_rhub) ||
+ !xhci_hub_ports_suspended(&xhci->usb3_rhub))
+ err = -EBUSY;
+
+ spin_unlock_irqrestore(&xhci->lock, flags);
+
+ return err;
+}
+
static void tegra_xusb_save_context(struct tegra_xusb *tegra)
{
const struct tegra_xusb_context_soc *soc = tegra->soc->context;
@@ -1481,31 +1520,103 @@ static void tegra_xusb_restore_context(struct tegra_xusb *tegra)
}
}
-static int tegra_xusb_suspend(struct device *dev)
+static int tegra_xusb_enter_elpg(struct tegra_xusb *tegra, bool wakeup)
{
- struct tegra_xusb *tegra = dev_get_drvdata(dev);
struct xhci_hcd *xhci = hcd_to_xhci(tegra->hcd);
- bool wakeup = device_may_wakeup(dev);
int err;
- /* TODO: Powergate controller across suspend/resume. */
+ err = tegra_xusb_check_ports(tegra);
+ if (err < 0) {
+ dev_err(tegra->dev, "not all ports suspended: %d\n", err);
+ return err;
+ }
+
err = xhci_suspend(xhci, wakeup);
- if (err < 0)
+ if (err < 0) {
+ dev_err(tegra->dev, "failed to suspend XHCI: %d\n", err);
return err;
+ }
tegra_xusb_save_context(tegra);
+ tegra_xusb_phy_disable(tegra);
+ tegra_xusb_clk_disable(tegra);
return 0;
}
-static int tegra_xusb_resume(struct device *dev)
+static int tegra_xusb_exit_elpg(struct tegra_xusb *tegra, bool wakeup)
{
- struct tegra_xusb *tegra = dev_get_drvdata(dev);
struct xhci_hcd *xhci = hcd_to_xhci(tegra->hcd);
+ int err;
+ err = tegra_xusb_clk_enable(tegra);
+ if (err < 0) {
+ dev_err(tegra->dev, "failed to enable clocks: %d\n", err);
+ return err;
+ }
+
+ err = tegra_xusb_phy_enable(tegra);
+ if (err < 0) {
+ dev_err(tegra->dev, "failed to enable PHYs: %d\n", err);
+ goto disable_clk;
+ }
+
+ tegra_xusb_config(tegra);
tegra_xusb_restore_context(tegra);
- return xhci_resume(xhci, false);
+ err = tegra_xusb_load_firmware(tegra);
+ if (err < 0) {
+ dev_err(tegra->dev, "failed to load firmware: %d\n", err);
+ goto disable_phy;
+ }
+
+ err = __tegra_xusb_enable_firmware_messages(tegra);
+ if (err < 0) {
+ dev_err(tegra->dev, "failed to enable messages: %d\n", err);
+ goto disable_phy;
+ }
+
+ err = xhci_resume(xhci, true);
+ if (err < 0) {
+ dev_err(tegra->dev, "failed to resume XHCI: %d\n", err);
+ goto disable_phy;
+ }
+
+ return 0;
+
+disable_phy:
+ tegra_xusb_phy_disable(tegra);
+disable_clk:
+ tegra_xusb_clk_disable(tegra);
+ return err;
+}
+
+static int tegra_xusb_suspend(struct device *dev)
+{
+ struct tegra_xusb *tegra = dev_get_drvdata(dev);
+ bool wakeup = device_may_wakeup(dev);
+ int err;
+
+ synchronize_irq(tegra->mbox_irq);
+
+ mutex_lock(&tegra->lock);
+ err = tegra_xusb_enter_elpg(tegra, wakeup);
+ mutex_unlock(&tegra->lock);
+
+ return err;
+}
+
+static int tegra_xusb_resume(struct device *dev)
+{
+ struct tegra_xusb *tegra = dev_get_drvdata(dev);
+ bool wakeup = device_may_wakeup(dev);
+ int err;
+
+ mutex_lock(&tegra->lock);
+ err = tegra_xusb_exit_elpg(tegra, wakeup);
+ mutex_unlock(&tegra->lock);
+
+ return err;
}
#endif
--
2.23.0
