[PATCH] phy: ti: twl4030-usb: free the IRQ before canceling work

[PATCH] phy: ti: twl4030-usb: free the IRQ before canceling work

[Myeonghun Pak]

The threaded IRQ handler can schedule id_workaround_work while the PHY
is runtime active. The remove callback cancels that work, but leaves
the managed IRQ registered until devres cleanup after remove returns.
An interrupt after the cancellation can therefore queue work that
accesses the freed twl4030_usb allocation.

The same work can be queued after IRQ registration if phy_create_lookup()
fails during probe. Failed probe cleanup releases the managed IRQ and
allocation without canceling the delayed work, and does not call remove.

Free the managed IRQ before canceling the delayed work on remove and on
the post-IRQ probe failure path. This waits for the threaded IRQ producer
to finish before canceling any work it queued. The synchronous work
cancellation also handles the worker's own requeueing. Generic PHY
consumer callbacks have separate lifetime requirements.

This issue was identified during our ongoing static-analysis research
while reviewing kernel code.

Fixes: 85601b8d81e2 ("usb: phy: twl4030-usb: Fix lost interrupts after ID pin goes down")
Cc: stable@vger.kernel.org
Assisted-by: LLM
Co-developed-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Myeonghun Pak <mhun512@gmail.com>
---
 drivers/phy/ti/phy-twl4030-usb.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/phy/ti/phy-twl4030-usb.c b/drivers/phy/ti/phy-twl4030-usb.c
index a26aec3ab29e..37c326cd1d85 100644
--- a/drivers/phy/ti/phy-twl4030-usb.c
+++ b/drivers/phy/ti/phy-twl4030-usb.c
@@ -779,12 +779,17 @@ static int twl4030_usb_probe(struct platform_device *pdev)
 	if (pdata)
 		err = phy_create_lookup(phy, "usb", "musb-hdrc.0");
 	if (err)
-		return err;
+		goto err_free_irq;
 
 	pm_runtime_mark_last_busy(&pdev->dev);
 	pm_runtime_put_autosuspend(twl->dev);
 
 	return 0;
+
+err_free_irq:
+	devm_free_irq(twl->dev, twl->irq, twl);
+	cancel_delayed_work_sync(&twl->id_workaround_work);
+	return err;
 }
 
 static void twl4030_usb_remove(struct platform_device *pdev)
@@ -794,6 +799,7 @@ static void twl4030_usb_remove(struct platform_device *pdev)
 
 	usb_remove_phy(&twl->phy);
 	pm_runtime_get_sync(twl->dev);
+	devm_free_irq(twl->dev, twl->irq, twl);
 	cancel_delayed_work_sync(&twl->id_workaround_work);
 	device_remove_file(twl->dev, &dev_attr_vbus);
 
-- 
2.53.0