usb: typec: tcpci: Don't skip cleanup in .remove() on error

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: 3ba7625 ("usb: typec: tcpci: mask event interrupts when remove driver")
Signed-off-by: Uwe Kleine-König <[email protected]>
Cc: stable <[email protected]>
Acked-by: Heikki Krogerus <[email protected]>
Reviewed-by: Guenter Roeck <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: Uwe Kleine-König

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);