usb: phy: dual-role: update sysfs attrs when changed

dual_role_instance_changed() is called by drivers when updating
the state of the dual_role port device. In some cases a driver
may wish to dynamically update the visibility, in particular the
write permissions of some of its attributes. For instance,
'data_role' and 'power_role' can be writeable if they can be
changed independently, as in the case of a USB PD capable device,
but may need to be set back to non-writeable when a non-PD device
is attached.

Add a call to sysfs_update_group() in dual_role_changed_work()
which updates the attributes by calling the .is_visible() callback
again, which in turn calls dual_role_property_is_writeable() to
re-check whether write permission should be set or not. Move
dual_role_changed_work() toward the end of the file as it now
needs the definition of dual_role_attr_group.

Change-Id: Ie58b37b63f052aced24db00b91e87deff9ffed7e
Signed-off-by: Jack Pham <jackp@codeaurora.org>

1 files changed, 12 insertions, 9 deletions

diff --git a/drivers/usb/phy/class-dual-role.c b/drivers/usb/phy/class-dual-role.c
index 51fcb545a9d5..9ef889593ef5 100644
--- a/drivers/usb/phy/class-dual-role.c
+++ b/drivers/usb/phy/class-dual-role.c
@@ -70,15 +70,7 @@ static char *kstrdupcase(const char *str, gfp_t gfp, bool to_upper)
 	return ret;
 }
 
-static void dual_role_changed_work(struct work_struct *work)
-{
-	struct dual_role_phy_instance *dual_role =
-	    container_of(work, struct dual_role_phy_instance,
-			 changed_work);
-
-	dev_dbg(&dual_role->dev, "%s\n", __func__);
-	kobject_uevent(&dual_role->dev.kobj, KOBJ_CHANGE);
-}
+static void dual_role_changed_work(struct work_struct *work);
 
 void dual_role_instance_changed(struct dual_role_phy_instance *dual_role)
 {
@@ -505,6 +497,17 @@ out:
 	return ret;
 }
 
+static void dual_role_changed_work(struct work_struct *work)
+{
+	struct dual_role_phy_instance *dual_role =
+	    container_of(work, struct dual_role_phy_instance,
+			 changed_work);
+
+	dev_dbg(&dual_role->dev, "%s\n", __func__);
+	sysfs_update_group(&dual_role->dev.kobj, &dual_role_attr_group);
+	kobject_uevent(&dual_role->dev.kobj, KOBJ_CHANGE);
+}
+
 /******************* Module Init ***********************************/
 
 static int __init dual_role_class_init(void)