kernel/linux.git/drivers/usb/roles, branch v5.10.257

usb: roles: get usb role switch from parent only for usb-b-connector

2026-04-18T08:31:00+00:00

[ Upstream commit 8345b1539faa49fcf9c9439c3cbd97dac6eca171 ] usb_role_switch_is_parent() was walking up to the parent node and checking for the "usb-role-switch" property regardless of the type of the passed fwnode. This could cause unrelated device nodes to be probed as potential role switch parent, leading to spurious matches and "-EPROBE_DEFER" being returned infinitely. Till now only Type-B connector node will have a parent node which may present "usb-role-switch" property and register the role switch device. For Type-C connector node, its parent node will always be a Type-C chip device which will never register the role switch device. However, it may still present a non-boolean "usb-role-switch = <&usb_controller>" property for historical compatibility. So restrict the helper to only operate on Type-B connector when attempting to get the role switch from parent node. Fixes: 6fadd72943b8 ("usb: roles: get usb-role-switch from parent") Cc: stable Signed-off-by: Xu Yang Tested-by: Arnaud Ferraris Reviewed-by: Heikki Krogerus Link: https://patch.msgid.link/20260309074313.2809867-3-xu.yang_2@nxp.com Signed-off-by: Greg Kroah-Hartman [ replace fwnode_device_is_compatible() call with it's expansion ] Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

usb: roles: set switch registered flag early on

2025-03-13T11:47:16+00:00

commit 634775a752a86784511018a108f3b530cc3399a7 upstream. The role switch registration and set_role() can happen in parallel as they are invoked independent of each other. There is a possibility that a driver might spend significant amount of time in usb_role_switch_register() API due to the presence of time intensive operations like component_add() which operate under common mutex. This leads to a time window after allocating the switch and before setting the registered flag where the set role notifications are dropped. Below timeline summarizes this behavior Thread1 | Thread2 usb_role_switch_register() | | | ---> allocate switch | | | ---> component_add() | usb_role_switch_set_role() | | | | | --> Drop role notifications | | since sw->registered | | flag is not set. | | --->Set registered flag.| To avoid this, set the registered flag early on in the switch register API. Fixes: b787a3e78175 ("usb: roles: don't get/set_role() when usb_role_switch is unregistered") Cc: stable Signed-off-by: Elson Roy Serrao Reviewed-by: Heikki Krogerus Link: https://lore.kernel.org/r/20250206193950.22421-1-quic_eserrao@quicinc.com Signed-off-by: Greg Kroah-Hartman

usb: roles: don't get/set_role() when usb_role_switch is unregistered

2024-03-01T12:16:49+00:00

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 Acked-by: Heikki Krogerus Link: https://lore.kernel.org/r/20240129093739.2371530-2-xu.yang_2@nxp.com Signed-off-by: Greg Kroah-Hartman

usb: roles: fix NULL pointer issue when put module's reference

2024-03-01T12:16:49+00:00

commit 1c9be13846c0b2abc2480602f8ef421360e1ad9e upstream. In current design, usb role class driver will get usb_role_switch parent's module reference after the user get usb_role_switch device and put the reference after the user put the usb_role_switch device. However, the parent device of usb_role_switch may be removed before the user put the usb_role_switch. If so, then, NULL pointer issue will be met when the user put the parent module's reference. This will save the module pointer in structure of usb_role_switch. Then, we don't need to find module by iterating long relations. Fixes: 5c54fcac9a9d ("usb: roles: Take care of driver module reference counting") cc: stable@vger.kernel.org Signed-off-by: Xu Yang Acked-by: Heikki Krogerus Link: https://lore.kernel.org/r/20240129093739.2371530-1-xu.yang_2@nxp.com Signed-off-by: Greg Kroah-Hartman

Revert "usb: common: usb-conn-gpio: Set last role to unknown before initial detection"

2023-07-27T06:44:06+00:00

[ Upstream commit df49f2a0ac4a34c0cb4b5c233fcfa0add644c43c ] This reverts commit edd60d24bd858cef165274e4cd6cab43bdc58d15. Heikki reports that this should not be a global flag just to work around one broken driver and should be fixed differently, so revert it. Reported-by: Heikki Krogerus Fixes: edd60d24bd85 ("usb: common: usb-conn-gpio: Set last role to unknown before initial detection") Link: https://lore.kernel.org/r/ZImE4L3YgABnCIsP@kuha.fi.intel.com Cc: Prashanth K Cc: AngeloGioacchino Del Regno Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

usb: common: usb-conn-gpio: Set last role to unknown before initial detection

2023-07-27T06:44:06+00:00

[ Upstream commit edd60d24bd858cef165274e4cd6cab43bdc58d15 ] Currently if we bootup a device without cable connected, then usb-conn-gpio won't call set_role() since last_role is same as current role. This happens because during probe last_role gets initialised to zero. To avoid this, added a new constant in enum usb_role, last_role is set to USB_ROLE_UNKNOWN before performing initial detection. While at it, also handle default case for the usb_role switch in cdns3, intel-xhci-usb-role-switch & musb/jz4740 to avoid build warnings. Fixes: 4602f3bff266 ("usb: common: add USB GPIO based connection detection driver") Signed-off-by: Prashanth K Reviewed-by: AngeloGioacchino Del Regno Message-ID: <1685544074-17337-1-git-send-email-quic_prashk@quicinc.com> Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

usb: roles: fix of node refcount leak in usb_role_switch_is_parent()

2023-01-14T09:15:59+00:00

[ Upstream commit 1ab30c610630da5391a373cddb8a065bf4c4bc01 ] I got the following report while doing device(mt6370-tcpc) load test with CONFIG_OF_UNITTEST and CONFIG_OF_DYNAMIC enabled: OF: ERROR: memory leak, expected refcount 1 instead of 2, of_node_get()/of_node_put() unbalanced - destroy cset entry: attach overlay node /i2c/pmic@34 The 'parent' returned by fwnode_get_parent() with refcount incremented. it needs be put after using. Fixes: 6fadd72943b8 ("usb: roles: get usb-role-switch from parent") Reviewed-by: Heikki Krogerus Signed-off-by: Yang Yingliang Link: https://lore.kernel.org/r/20221122111226.251588-1-yangyingliang@huawei.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

usb: roles: Call try_module_get() from usb_role_switch_find_by_fwnode()

2021-05-14T07:49:55+00:00

commit 3a2a91a2d51761557843996a66098eb7182b48b4 upstream. usb_role_switch_find_by_fwnode() returns a reference to the role-switch which must be put by calling usb_role_switch_put(). usb_role_switch_put() calls module_put(sw->dev.parent->driver->owner), add a matching try_module_get() to usb_role_switch_find_by_fwnode(), making it behave the same as the other usb_role_switch functions which return a reference. This avoids a WARN_ON being hit at kernel/module.c:1158 due to the module-refcount going below 0. Fixes: c6919d5e0cd1 ("usb: roles: Add usb_role_switch_find_by_fwnode()") Cc: stable Reviewed-by: Guenter Roeck Reviewed-by: Heikki Krogerus Signed-off-by: Hans de Goede Link: https://lore.kernel.org/r/20210409124136.65591-1-hdegoede@redhat.com Signed-off-by: Greg Kroah-Hartman

device connection: Remove struct device_connection

2020-09-07T09:14:09+00:00

Since the connection descriptors can't be stored into the list anymore, there is no need for the data structure. Signed-off-by: Heikki Krogerus Link: https://lore.kernel.org/r/20200904125123.83725-4-heikki.krogerus@linux.intel.com Signed-off-by: Greg Kroah-Hartman

usb: roles: Switch on role-switch uevent reporting

2020-05-13T12:20:49+00:00

Right now we don't report to user-space a role switch when doing a usb_role_switch_set_role() despite having registered the uevent callbacks. This patch switches on the notifications allowing user-space to see role-switch change notifications and subsequently determine the current controller data-role. example: PFX=/devices/platform/soc/78d9000.usb/ci_hdrc.0 root@somebox# udevadm monitor -p KERNEL[49.894994] change $PFX/usb_role/ci_hdrc.0-role-switch (usb_role) ACTION=change DEVPATH=$PFX/usb_role/ci_hdrc.0-role-switch SUBSYSTEM=usb_role DEVTYPE=usb_role_switch USB_ROLE_SWITCH=ci_hdrc.0-role-switch SEQNUM=2432 Cc: Heikki Krogerus Cc: Greg Kroah-Hartman Cc: Chunfeng Yun Cc: Suzuki K Poulose Cc: Alexandre Belloni Cc: Wen Yang Cc: chenqiwu Cc: linux-kernel@vger.kernel.org Signed-off-by: Bryan O'Donoghue Link: https://lore.kernel.org/r/20200508162937.2566818-1-bryan.odonoghue@linaro.org Signed-off-by: Greg Kroah-Hartman