From: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Date: Fri, 8 May 2020 17:29:37 +0100
Subject: usb: roles: Switch on role-switch uevent reporting
Git-commit: 3e63cff384e625f09758ce8f4d01ae3033402b63
Patch-mainline: v5.8-rc1
References: jsc#SLE-13918
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 <heikki.krogerus@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Chunfeng Yun <chunfeng.yun@mediatek.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Wen Yang <wenyang@linux.alibaba.com>
Cc: chenqiwu <chenqiwu@xiaomi.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Link: https://lore.kernel.org/r/20200508162937.2566818-1-bryan.odonoghue@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
---
drivers/usb/roles/class.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/roles/class.c b/drivers/usb/roles/class.c
index 5b17709821df..27d92af29635 100644
--- a/drivers/usb/roles/class.c
+++ b/drivers/usb/roles/class.c
@@ -49,8 +49,10 @@ int usb_role_switch_set_role(struct usb_role_switch *sw, enum usb_role role)
mutex_lock(&sw->lock);
ret = sw->set(sw, role);
- if (!ret)
+ if (!ret) {
sw->role = role;
+ kobject_uevent(&sw->dev.kobj, KOBJ_CHANGE);
+ }
mutex_unlock(&sw->lock);