[PATCH v3] usb: xhci: tegra: Check padctrl interrupt presence in device tree

[Dmitry Osipenko <digetx@gmail.com>]

Older device-trees don't specify padctrl interrupt and xhci-tegra driver
now fails to probe with -EINVAL using those device-trees. Check interrupt
presence and keep runtime PM disabled if it's missing to fix the trouble.

Fixes: 971ee247060d ("usb: xhci: tegra: Enable ELPG for runtime/system PM")
Cc: <stable@vger.kernel.org> # 5.14+
Reported-by: Nicolas Chauvet <kwizart@gmail.com>
Tested-by: Nicolas Chauvet <kwizart@gmail.com> # T124 TK1
Tested-by: Thomas Graichen <thomas.graichen@gmail.com> # T124 Nyan Big
Tested-by: Thierry Reding <treding@nvidia.com> # Tegra CI
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---

Changelog:

v3: - Renamed 'irq_arg' to 'args' and extended debug message, like was
      suggested by Thierry Reding.

    - Added t-b from Thomas Graichen and ack from Thierry Reding.

v2: - Use of_irq_parse_one() to check interrupt presence status in device-tree,
      instead of checking interrupt properties directly.

    - USB wakeup and runtime PM are kept disabled if interrupt is missing,
      instead of returning -EOPNOTSUPP from RPM-suspend callback.

    - Added debug message, telling about the missing interrupt.

 drivers/usb/host/xhci-tegra.c | 41 +++++++++++++++++++++++++----------
 1 file changed, 29 insertions(+), 12 deletions(-)

diff --git a/drivers/usb/host/xhci-tegra.c b/drivers/usb/host/xhci-tegra.c
index 1bf494b649bd..c8af2cd2216d 100644
--- a/drivers/usb/host/xhci-tegra.c
+++ b/drivers/usb/host/xhci-tegra.c
@@ -1400,6 +1400,7 @@ static void tegra_xusb_deinit_usb_phy(struct tegra_xusb *tegra)
 
 static int tegra_xusb_probe(struct platform_device *pdev)
 {
+	struct of_phandle_args args;
 	struct tegra_xusb *tegra;
 	struct device_node *np;
 	struct resource *regs;
@@ -1454,10 +1455,17 @@ static int tegra_xusb_probe(struct platform_device *pdev)
 		goto put_padctl;
 	}
 
-	tegra->padctl_irq = of_irq_get(np, 0);
-	if (tegra->padctl_irq <= 0) {
-		err = (tegra->padctl_irq == 0) ? -ENODEV : tegra->padctl_irq;
-		goto put_padctl;
+	/* Older device-trees don't have padctrl interrupt */
+	err = of_irq_parse_one(np, 0, &args);
+	if (!err) {
+		tegra->padctl_irq = of_irq_get(np, 0);
+		if (tegra->padctl_irq <= 0) {
+			err = (tegra->padctl_irq == 0) ? -ENODEV : tegra->padctl_irq;
+			goto put_padctl;
+		}
+	} else {
+		dev_dbg(&pdev->dev,
+			"%pOF is missing an interrupt, disabling PM support\n", np);
 	}
 
 	tegra->host_clk = devm_clk_get(&pdev->dev, "xusb_host");
@@ -1696,11 +1704,15 @@ static int tegra_xusb_probe(struct platform_device *pdev)
 		goto remove_usb3;
 	}
 
-	err = devm_request_threaded_irq(&pdev->dev, tegra->padctl_irq, NULL, tegra_xusb_padctl_irq,
-					IRQF_ONESHOT, dev_name(&pdev->dev), tegra);
-	if (err < 0) {
-		dev_err(&pdev->dev, "failed to request padctl IRQ: %d\n", err);
-		goto remove_usb3;
+	if (tegra->padctl_irq) {
+		err = devm_request_threaded_irq(&pdev->dev, tegra->padctl_irq,
+						NULL, tegra_xusb_padctl_irq,
+						IRQF_ONESHOT, dev_name(&pdev->dev),
+						tegra);
+		if (err < 0) {
+			dev_err(&pdev->dev, "failed to request padctl IRQ: %d\n", err);
+			goto remove_usb3;
+		}
 	}
 
 	err = tegra_xusb_enable_firmware_messages(tegra);
@@ -1718,13 +1730,16 @@ static int tegra_xusb_probe(struct platform_device *pdev)
 	/* Enable wake for both USB 2.0 and USB 3.0 roothubs */
 	device_init_wakeup(&tegra->hcd->self.root_hub->dev, true);
 	device_init_wakeup(&xhci->shared_hcd->self.root_hub->dev, true);
-	device_init_wakeup(tegra->dev, true);
 
 	pm_runtime_use_autosuspend(tegra->dev);
 	pm_runtime_set_autosuspend_delay(tegra->dev, 2000);
 	pm_runtime_mark_last_busy(tegra->dev);
 	pm_runtime_set_active(tegra->dev);
-	pm_runtime_enable(tegra->dev);
+
+	if (tegra->padctl_irq) {
+		device_init_wakeup(tegra->dev, true);
+		pm_runtime_enable(tegra->dev);
+	}
 
 	return 0;
 
@@ -1772,7 +1787,9 @@ static int tegra_xusb_remove(struct platform_device *pdev)
 	dma_free_coherent(&pdev->dev, tegra->fw.size, tegra->fw.virt,
 			  tegra->fw.phys);
 
-	pm_runtime_disable(&pdev->dev);
+	if (tegra->padctl_irq)
+		pm_runtime_disable(&pdev->dev);
+
 	pm_runtime_put(&pdev->dev);
 
 	tegra_xusb_powergate_partitions(tegra);
-- 
2.33.1