diff options
| author | Roy Luo <royluo@google.com> | 2024-03-07 06:09:22 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-03-26 12:43:15 +0300 |
| commit | 0ef40f399aa2be8c04aee9b7430705612c104ce5 (patch) | |
| tree | 6e8cf6adbc6cb7cbbc3a36c0927604fb34af71a7 | |
| parent | 2f550553e23c889b54440bf05e2484d84105e48d (diff) | |
| download | linux-0ef40f399aa2be8c04aee9b7430705612c104ce5.tar.xz | |
USB: gadget: core: create sysfs link between udc and gadget
udc device and gadget device are tightly coupled, yet there's no good
way to corelate the two. Add a sysfs link in udc that points to the
corresponding gadget device.
An example use case: userspace configures a f_midi configfs driver and
bind the udc device, then it tries to locate the corresponding midi
device, which is a child device of the gadget device. The gadget device
that's associated to the udc device has to be identified in order to
index the midi device. Having a sysfs link would make things much
easier.
Signed-off-by: Roy Luo <royluo@google.com>
Link: https://lore.kernel.org/r/20240307030922.3573161-1-royluo@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/usb/gadget/udc/core.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c index 9d4150124fdb..76d890f9a40f 100644 --- a/drivers/usb/gadget/udc/core.c +++ b/drivers/usb/gadget/udc/core.c @@ -1424,8 +1424,16 @@ int usb_add_gadget(struct usb_gadget *gadget) if (ret) goto err_free_id; + ret = sysfs_create_link(&udc->dev.kobj, + &gadget->dev.kobj, "gadget"); + if (ret) + goto err_del_gadget; + return 0; + err_del_gadget: + device_del(&gadget->dev); + err_free_id: ida_free(&gadget_id_numbers, gadget->id_number); @@ -1534,6 +1542,7 @@ void usb_del_gadget(struct usb_gadget *gadget) mutex_unlock(&udc_lock); kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE); + sysfs_remove_link(&udc->dev.kobj, "gadget"); flush_work(&gadget->work); device_del(&gadget->dev); ida_free(&gadget_id_numbers, gadget->id_number); |