On 5/2/22 01:04, Uwe Kleine-König wrote:
Returning an error value in an i2c remove callback results in an error
message being emitted by the i2c core, but otherwise it doesn't make a
difference. The device goes away anyhow and the devm cleanups are
called.
In this case the remove callback even returns early without stopping the
tcpm worker thread and various timers. A work scheduled on the work
queue, or a firing timer after tcpci_remove() returned probably results
in a use-after-free situation because the regmap and driver data were
freed. So better make sure that tcpci_unregister_port() is called even
if disabling the irq failed.
Also emit a more specific error message instead of the i2c core's
"remove failed (EIO), will be ignored" and return 0 to suppress the
core's warning.
This patch is (also) a preparation for making i2c remove callbacks
return void.
Fixes: 3ba76256fc4e ("usb: typec: tcpci: mask event interrupts when remove driver")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>
---
drivers/usb/typec/tcpm/tcpci.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/usb/typec/tcpm/tcpci.c b/drivers/usb/typec/tcpm/tcpci.c
index e07d26a3cd8e..f33e08eb7670 100644
--- a/drivers/usb/typec/tcpm/tcpci.c
+++ b/drivers/usb/typec/tcpm/tcpci.c
@@ -877,7 +877,7 @@ static int tcpci_remove(struct i2c_client *client)
/* Disable chip interrupts before unregistering port */
err = tcpci_write16(chip->tcpci, TCPC_ALERT_MASK, 0);
if (err < 0)
- return err;
+ dev_warn(&client->dev, "Failed to disable irqs (%pe)\n", ERR_PTR(err));
tcpci_unregister_port(chip->tcpci);
base-commit: 3123109284176b1532874591f7c81f3837bbdc17
