[PATCH 7/7] USB: cdc-acm: always claim data interface

From: Johan Hovold
Date: Thu Mar 18 2021 - 11:53:38 EST


Make sure to always claim the data interface and bail out if it's
already bound to another driver or isn't authorised.

Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
---
drivers/usb/class/cdc-acm.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 6991ffd66c5d..58c444f9db5e 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -1486,7 +1486,11 @@ static int acm_probe(struct usb_interface *intf,
acm->line.bDataBits = 8;
acm_set_line(acm, &acm->line);

- usb_driver_claim_interface(&acm_driver, data_interface, acm);
+ if (!acm->combined_interfaces) {
+ rv = usb_driver_claim_interface(&acm_driver, data_interface, acm);
+ if (rv)
+ goto err_remove_files;
+ }

tty_dev = tty_port_register_device(&acm->port, acm_tty_driver, minor,
&control_interface->dev);
@@ -1508,6 +1512,7 @@ static int acm_probe(struct usb_interface *intf,
usb_set_intfdata(data_interface, NULL);
usb_driver_release_interface(&acm_driver, data_interface);
}
+err_remove_files:
if (acm->country_codes) {
device_remove_file(&acm->control->dev,
&dev_attr_wCountryCodes);
--
2.26.2