diff options
| author | Xu Yang <xu.yang_2@nxp.com> | 2024-01-29 12:37:39 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-03-01 15:26:34 +0300 |
| commit | 2f414a56b369129cfdac6ecaf9899f9807a264aa (patch) | |
| tree | 1f306d6dc0d57f0e936e75d0be463d7c1085d70d /drivers/usb | |
| parent | 0158216805ca7e498d07de38840d2732166ae5fa (diff) | |
| download | linux-2f414a56b369129cfdac6ecaf9899f9807a264aa.tar.xz | |
usb: roles: don't get/set_role() when usb_role_switch is unregistered
commit b787a3e781759026a6212736ef8e52cf83d1821a upstream.
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')
| -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 d90d16423809..a327f8bc5704 100644 --- a/drivers/usb/roles/class.c +++ b/drivers/usb/roles/class.c @@ -21,6 +21,7 @@ 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; @@ -47,6 +48,9 @@ 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); @@ -72,7 +76,7 @@ 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); @@ -356,6 +360,8 @@ 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; @@ -370,8 +376,10 @@ 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); |