[PATCH v2] usb: dwc3: fix runtime PM in error path

[Roger Quadros <rogerq@ti.com>]

If there is a failure after pm_runtime_enable/get_sync()
we need to call pm_runtime_disable/put_sync().

Otherwise it will lead to an unbalanced pm_runtime_enable() on the
subsequent probe if the earlier probe bailed out due to -EPROBE_DEFER.

pm_runtime_get_sync() can fail as well so deal with that case too.

Signed-off-by: Roger Quadros <rogerq@ti.com>
---
v2:
- deal with pm_runtime_get_sync() failure

 drivers/usb/dwc3/core.c | 25 +++++++++++++++++--------
 1 file changed, 17 insertions(+), 8 deletions(-)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 131e7eb..d51c9a9 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -959,14 +959,17 @@ static int dwc3_probe(struct platform_device *pdev)
 	pm_runtime_use_autosuspend(dev);
 	pm_runtime_set_autosuspend_delay(dev, DWC3_DEFAULT_AUTOSUSPEND_DELAY);
 	pm_runtime_enable(dev);
-	pm_runtime_get_sync(dev);
+	ret = pm_runtime_get_sync(dev);
+	if (ret < 0)
+		goto err1;
+
 	pm_runtime_forbid(dev);
 
 	ret = dwc3_alloc_event_buffers(dwc, DWC3_EVENT_BUFFERS_SIZE);
 	if (ret) {
 		dev_err(dwc->dev, "failed to allocate event buffers\n");
 		ret = -ENOMEM;
-		goto err0;
+		goto err2;
 	}
 
 	if (IS_ENABLED(CONFIG_USB_DWC3_HOST) &&
@@ -983,12 +986,12 @@ static int dwc3_probe(struct platform_device *pdev)
 
 	ret = dwc3_alloc_scratch_buffers(dwc);
 	if (ret)
-		goto err1;
+		goto err3;
 
 	ret = dwc3_core_init(dwc);
 	if (ret) {
 		dev_err(dev, "failed to initialize core\n");
-		goto err2;
+		goto err4;
 	}
 
 	/* Check the maximum_speed parameter */
@@ -1020,23 +1023,29 @@ static int dwc3_probe(struct platform_device *pdev)
 
 	ret = dwc3_core_init_mode(dwc);
 	if (ret)
-		goto err3;
+		goto err5;
 
 	dwc3_debugfs_init(dwc);
 	pm_runtime_put(dev);
 
 	return 0;
 
-err3:
+err5:
 	dwc3_event_buffers_cleanup(dwc);
 
-err2:
+err4:
 	dwc3_free_scratch_buffers(dwc);
 
-err1:
+err3:
 	dwc3_free_event_buffers(dwc);
 	dwc3_ulpi_exit(dwc);
 
+err2:
+	pm_runtime_allow(&pdev->dev);
+err1:
+	pm_runtime_put_sync(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+
 err0:
 	/*
 	 * restore res->start back to its original value so that, in case the
-- 
2.7.4