[PATCH v3] usb: chipidea: core: convert ci_role_switch to local variable

[PATCH v3] usb: chipidea: core: convert ci_role_switch to local variable

[Xu Yang]

When a system contains multiple USB controllers, the global ci_role_switch
variable may be overwritten by subsequent driver initialization code.

This can cause issues in the following cases:
 - The 2nd ci_hdrc_probe() sees ci_role_switch.fwnode as non-NULL even
   though the "usb-role-switch" property is not present for the controller.
 - When the ci_hdrc device is unbound and bound again, ci_role_switch
   fwnode will not be reassigned, and the old value will be used instead.

Convert ci_role_switch to a local variable to fix these issues.

Fixes: 05559f10ed79 ("usb: chipidea: add role switch class support")
Cc: stable@vger.kernel.org
Acked-by: Peter Chen <peter.chen@kernel.org>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Xu Yang <xu.yang_2@nxp.com>

---
Changes in v2:
 - add R-b and A-b tag
Changes in v3:
 - no change
---
 drivers/usb/chipidea/core.c | 16 ++++++----------
 1 file changed, 6 insertions(+), 10 deletions(-)

diff --git a/drivers/usb/chipidea/core.c b/drivers/usb/chipidea/core.c
index 95d9db159ce8..07563be0013f 100644
--- a/drivers/usb/chipidea/core.c
+++ b/drivers/usb/chipidea/core.c
@@ -655,12 +655,6 @@ static enum ci_role ci_get_role(struct ci_hdrc *ci)
 	return role;
 }
 
-static struct usb_role_switch_desc ci_role_switch = {
-	.set = ci_usb_role_switch_set,
-	.get = ci_usb_role_switch_get,
-	.allow_userspace_control = true,
-};
-
 static int ci_get_platdata(struct device *dev,
 		struct ci_hdrc_platform_data *platdata)
 {
@@ -787,9 +781,6 @@ static int ci_get_platdata(struct device *dev,
 			cable->connected = false;
 	}
 
-	if (device_property_read_bool(dev, "usb-role-switch"))
-		ci_role_switch.fwnode = dev->fwnode;
-
 	platdata->pctl = devm_pinctrl_get(dev);
 	if (!IS_ERR(platdata->pctl)) {
 		struct pinctrl_state *p;
@@ -1033,6 +1024,7 @@ ATTRIBUTE_GROUPS(ci);
 
 static int ci_hdrc_probe(struct platform_device *pdev)
 {
+	struct usb_role_switch_desc ci_role_switch = {};
 	struct device	*dev = &pdev->dev;
 	struct ci_hdrc	*ci;
 	struct resource	*res;
@@ -1179,7 +1171,11 @@ static int ci_hdrc_probe(struct platform_device *pdev)
 		}
 	}
 
-	if (ci_role_switch.fwnode) {
+	if (device_property_read_bool(dev, "usb-role-switch")) {
+		ci_role_switch.set = ci_usb_role_switch_set;
+		ci_role_switch.get = ci_usb_role_switch_get;
+		ci_role_switch.allow_userspace_control = true;
+		ci_role_switch.fwnode = dev_fwnode(dev);
 		ci_role_switch.driver_data = ci;
 		ci->role_switch = usb_role_switch_register(dev,
 					&ci_role_switch);
-- 
2.34.1