diff options
| author | Xu Yang <xu.yang_2@nxp.com> | 2024-01-29 17:37:39 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-02-19 09:30:41 +0100 |
| commit | b787a3e781759026a6212736ef8e52cf83d1821a (patch) | |
| tree | b89460d5f0b50f3591a328183d1325a54dc239a8 /drivers/usb/roles/class.c | |
| parent | 1c9be13846c0b2abc2480602f8ef421360e1ad9e (diff) | |
usb: roles: don't get/set_role() when usb_role_switch is unregistered
There is a possibility that usb_role_switch device is unregistered before
the user put usb_role_switch. In this case, the user may still want to
get/set_role() since the user can't sense the changes of usb_role_switch.
This will add a flag to show if usb_role_switch is already registered and
avoid unwanted behaviors.
Fixes: fde0aa6c175a ("usb: common: Small class for USB role switches")
cc: stable@vger.kernel.org
Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20240129093739.2371530-2-xu.yang_2@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/roles/class.c')
| -rw-r--r-- | drivers/usb/roles/class.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/drivers/usb/roles/class.c b/drivers/usb/roles/class.c index 2bad038fb9ad..70165dd86b5d 100644 --- a/drivers/usb/roles/class.c +++ b/drivers/usb/roles/class.c @@ -23,6 +23,7 @@ struct usb_role_switch { struct mutex lock; /* device lock*/ struct module *module; /* the module this device depends on */ enum usb_role role; + bool registered; /* From descriptor */ struct device *usb2_port; @@ -49,6 +50,9 @@ int usb_role_switch_set_role(struct usb_role_switch *sw, enum usb_role role) if (IS_ERR_OR_NULL(sw)) return 0; + if (!sw->registered) + return -EOPNOTSUPP; + mutex_lock(&sw->lock); ret = sw->set(sw, role); @@ -74,7 +78,7 @@ enum usb_role usb_role_switch_get_role(struct usb_role_switch *sw) { enum usb_role role; - if (IS_ERR_OR_NULL(sw)) + if (IS_ERR_OR_NULL(sw) || !sw->registered) return USB_ROLE_NONE; mutex_lock(&sw->lock); @@ -357,6 +361,8 @@ usb_role_switch_register(struct device *parent, return ERR_PTR(ret); } + sw->registered = true; + /* TODO: Symlinks for the host port and the device controller. */ return sw; @@ -371,8 +377,10 @@ EXPORT_SYMBOL_GPL(usb_role_switch_register); */ void usb_role_switch_unregister(struct usb_role_switch *sw) { - if (!IS_ERR_OR_NULL(sw)) + if (!IS_ERR_OR_NULL(sw)) { + sw->registered = false; device_unregister(&sw->dev); + } } EXPORT_SYMBOL_GPL(usb_role_switch_unregister); |