diff options
| author | Stephan Gerhold <stephan.gerhold@linaro.org> | 2025-04-07 16:59:35 +0200 |
|---|---|---|
| committer | Mattijs Korpershoek <mkorpershoek@kernel.org> | 2025-04-23 09:50:52 +0200 |
| commit | eeef1223025c68bd546a1f9411bdcdf518f8cb97 (patch) | |
| tree | 10c41d172c2132118f4515d312f69b733fbea6c6 | |
| parent | 4446bc331c65d3efb8a9321d6368c61edb56479b (diff) | |
usb: gadget: f_acm: Claim requested USB endpoints
U-Boot has an older version of the Linux gadget API, where USB endpoints
returned by usb_ep_autoconfig() are not automatically claimed. As written
in the documentation comment:
"To prevent the endpoint from being returned by a later autoconfig call,
claim it by assigning ep->driver_data to some non-null value."
Right now f_acm doesn't do that, which means that e.g. ep_in and ep_notify
may end up being assigned the same endpoint. Surprisingly, the ACM console
is still somehow working, but this is not the expected behavior. It will
break with a later commit that disallows calling usb_ep_enable() multiple
times.
Fix this by assigning some data to ep->driver_data, similar to the other
gadget drivers.
Fixes: fc2b399ac03b ("usb: gadget: Add CDC ACM function")
Signed-off-by: Stephan Gerhold <stephan.gerhold@linaro.org>
Reviewed-by: Mattijs Korpershoek <mkorpershoek@kernel.org>
Link: https://lore.kernel.org/r/20250407-acm-fixes-v1-1-e3dcb592d6d6@linaro.org
Signed-off-by: Mattijs Korpershoek <mkorpershoek@kernel.org>
| -rw-r--r-- | drivers/usb/gadget/f_acm.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/usb/gadget/f_acm.c b/drivers/usb/gadget/f_acm.c index f18c6a0a761..2665fa4168f 100644 --- a/drivers/usb/gadget/f_acm.c +++ b/drivers/usb/gadget/f_acm.c @@ -238,18 +238,21 @@ static int acm_bind(struct usb_configuration *c, struct usb_function *f) return -ENODEV; f_acm->ep_in = ep; + ep->driver_data = c->cdev; /* claim */ ep = usb_ep_autoconfig(gadget, &acm_fs_out_desc); if (!ep) return -ENODEV; f_acm->ep_out = ep; + ep->driver_data = c->cdev; /* claim */ ep = usb_ep_autoconfig(gadget, &acm_fs_notify_desc); if (!ep) return -ENODEV; f_acm->ep_notify = ep; + ep->driver_data = c->cdev; /* claim */ if (gadget_is_dualspeed(gadget)) { /* Assume endpoint addresses are the same for both speeds */ |