usb: xhci-mtk: add support runtime PM

A dedicated wakeup irq will be used to handle runtime suspend/resume,
we use dev_pm_set_dedicated_wake_irq API to take care of requesting
and attaching wakeup irq, then the suspend/resume framework will help
to enable/disable wakeup irq.

The runtime PM is default off since some platforms may not support it.
users can enable it via power/control (set "auto") in sysfs.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/1618031406-15347-3-git-send-email-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/host/xhci-mtk.c b/drivers/usb/host/xhci-mtk.c
index d8a8d25..93d45e0 100644 (file)
--- a/drivers/usb/host/xhci-mtk.c
+++ b/drivers/usb/host/xhci-mtk.c
@@ -16,6 +16,7 @@
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
+#include <linux/pm_wakeirq.h>
 #include <linux/regmap.h>
 #include <linux/regulator/consumer.h>
 
@@ -358,7 +359,6 @@ static int usb_wakeup_of_property_parse(struct xhci_hcd_mtk *mtk,
                        mtk->uwk_reg_base, mtk->uwk_vers);
 
        return PTR_ERR_OR_ZERO(mtk->uwk);
-
 }
 
 static void usb_wakeup_set(struct xhci_hcd_mtk *mtk, bool enable)
@@ -467,6 +467,7 @@ static int xhci_mtk_probe(struct platform_device *pdev)
        struct resource *res;
        struct usb_hcd *hcd;
        int ret = -ENODEV;
+       int wakeup_irq;
        int irq;
 
        if (usb_disabled())
@@ -494,6 +495,21 @@ static int xhci_mtk_probe(struct platform_device *pdev)
        if (ret)
                return ret;
 
+       irq = platform_get_irq_byname_optional(pdev, "host");
+       if (irq < 0) {
+               if (irq == -EPROBE_DEFER)
+                       return irq;
+
+               /* for backward compatibility */
+               irq = platform_get_irq(pdev, 0);
+               if (irq < 0)
+                       return irq;
+       }
+
+       wakeup_irq = platform_get_irq_byname_optional(pdev, "wakeup");
+       if (wakeup_irq == -EPROBE_DEFER)
+               return wakeup_irq;
+
        mtk->lpm_support = of_property_read_bool(node, "usb3-lpm-capable");
        mtk->u2_lpm_disable = of_property_read_bool(node, "usb2-lpm-disable");
        /* optional property, ignore the error if it does not exist */
@@ -506,9 +522,11 @@ static int xhci_mtk_probe(struct platform_device *pdev)
                return ret;
        }
 
+       pm_runtime_set_active(dev);
+       pm_runtime_use_autosuspend(dev);
+       pm_runtime_set_autosuspend_delay(dev, 4000);
        pm_runtime_enable(dev);
        pm_runtime_get_sync(dev);
-       device_enable_async_suspend(dev);
 
        ret = xhci_mtk_ldos_enable(mtk);
        if (ret)
@@ -518,12 +536,6 @@ static int xhci_mtk_probe(struct platform_device *pdev)
        if (ret)
                goto disable_ldos;
 
-       irq = platform_get_irq(pdev, 0);
-       if (irq < 0) {
-               ret = irq;
-               goto disable_clk;
-       }
-
        hcd = usb_create_hcd(driver, dev, dev_name(dev));
        if (!hcd) {
                ret = -ENOMEM;
@@ -590,8 +602,26 @@ static int xhci_mtk_probe(struct platform_device *pdev)
        if (ret)
                goto dealloc_usb2_hcd;
 
+       if (wakeup_irq > 0) {
+               ret = dev_pm_set_dedicated_wake_irq(dev, wakeup_irq);
+               if (ret) {
+                       dev_err(dev, "set wakeup irq %d failed\n", wakeup_irq);
+                       goto dealloc_usb3_hcd;
+               }
+               dev_info(dev, "wakeup irq %d\n", wakeup_irq);
+       }
+
+       device_enable_async_suspend(dev);
+       pm_runtime_mark_last_busy(dev);
+       pm_runtime_put_autosuspend(dev);
+       pm_runtime_forbid(dev);
+
        return 0;
 
+dealloc_usb3_hcd:
+       usb_remove_hcd(xhci->shared_hcd);
+       xhci->shared_hcd = NULL;
+
 dealloc_usb2_hcd:
        usb_remove_hcd(hcd);
 
@@ -612,25 +642,26 @@ disable_ldos:
        xhci_mtk_ldos_disable(mtk);
 
 disable_pm:
-       pm_runtime_put_sync(dev);
+       pm_runtime_put_sync_autosuspend(dev);
        pm_runtime_disable(dev);
        return ret;
 }
 
-static int xhci_mtk_remove(struct platform_device *dev)
+static int xhci_mtk_remove(struct platform_device *pdev)
 {
-       struct xhci_hcd_mtk *mtk = platform_get_drvdata(dev);
+       struct xhci_hcd_mtk *mtk = platform_get_drvdata(pdev);
        struct usb_hcd  *hcd = mtk->hcd;
        struct xhci_hcd *xhci = hcd_to_xhci(hcd);
        struct usb_hcd  *shared_hcd = xhci->shared_hcd;
+       struct device *dev = &pdev->dev;
 
-       pm_runtime_put_noidle(&dev->dev);
-       pm_runtime_disable(&dev->dev);
+       pm_runtime_get_sync(dev);
+       xhci->xhc_state |= XHCI_STATE_REMOVING;
+       dev_pm_clear_wake_irq(dev);
+       device_init_wakeup(dev, false);
 
        usb_remove_hcd(shared_hcd);
        xhci->shared_hcd = NULL;
-       device_init_wakeup(&dev->dev, false);
-
        usb_remove_hcd(hcd);
        usb_put_hcd(shared_hcd);
        usb_put_hcd(hcd);
@@ -638,6 +669,10 @@ static int xhci_mtk_remove(struct platform_device *dev)
        xhci_mtk_clks_disable(mtk);
        xhci_mtk_ldos_disable(mtk);
 
+       pm_runtime_disable(dev);
+       pm_runtime_put_noidle(dev);
+       pm_runtime_set_suspended(dev);
+
        return 0;
 }
 
@@ -701,10 +736,83 @@ enable_wakeup:
        return ret;
 }
 
+static int check_rhub_status(struct xhci_hcd *xhci, struct xhci_hub *rhub)
+{
+       u32 suspended_ports;
+       u32 status;
+       int num_ports;
+       int i;
+
+       num_ports = rhub->num_ports;
+       suspended_ports = rhub->bus_state.suspended_ports;
+       for (i = 0; i < num_ports; i++) {
+               if (!(suspended_ports & BIT(i))) {
+                       status = readl(rhub->ports[i]->addr);
+                       if (status & PORT_CONNECT)
+                               return -EBUSY;
+               }
+       }
+
+       return 0;
+}
+
+/*
+ * check the bus whether it could suspend or not
+ * the bus will suspend if the downstream ports are already suspended,
+ * or no devices connected.
+ */
+static int check_bus_status(struct xhci_hcd *xhci)
+{
+       int ret;
+
+       ret = check_rhub_status(xhci, &xhci->usb3_rhub);
+       if (ret)
+               return ret;
+
+       return check_rhub_status(xhci, &xhci->usb2_rhub);
+}
+
+static int __maybe_unused xhci_mtk_runtime_suspend(struct device *dev)
+{
+       struct xhci_hcd_mtk  *mtk = dev_get_drvdata(dev);
+       struct xhci_hcd *xhci = hcd_to_xhci(mtk->hcd);
+       int ret = 0;
+
+       if (xhci->xhc_state)
+               return -ESHUTDOWN;
+
+       if (device_may_wakeup(dev)) {
+               ret = check_bus_status(xhci);
+               if (!ret)
+                       ret = xhci_mtk_suspend(dev);
+       }
+
+       /* -EBUSY: let PM automatically reschedule another autosuspend */
+       return ret ? -EBUSY : 0;
+}
+
+static int __maybe_unused xhci_mtk_runtime_resume(struct device *dev)
+{
+       struct xhci_hcd_mtk  *mtk = dev_get_drvdata(dev);
+       struct xhci_hcd *xhci = hcd_to_xhci(mtk->hcd);
+       int ret = 0;
+
+       if (xhci->xhc_state)
+               return -ESHUTDOWN;
+
+       if (device_may_wakeup(dev))
+               ret = xhci_mtk_resume(dev);
+
+       return ret;
+}
+
 static const struct dev_pm_ops xhci_mtk_pm_ops = {
        SET_SYSTEM_SLEEP_PM_OPS(xhci_mtk_suspend, xhci_mtk_resume)
+       SET_RUNTIME_PM_OPS(xhci_mtk_runtime_suspend,
+                          xhci_mtk_runtime_resume, NULL)
 };
-#define DEV_PM_OPS IS_ENABLED(CONFIG_PM) ? &xhci_mtk_pm_ops : NULL
+
+#define DEV_PM_OPS (IS_ENABLED(CONFIG_PM) ? &xhci_mtk_pm_ops : NULL)
 
 static const struct of_device_id mtk_xhci_of_match[] = {
        { .compatible = "mediatek,mt8173-xhci"},