usb: phy: show USB charger type for user

Current USB charger framework only shows charger state for user, but the
user may also need charger type for further use, add support for it.
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Link: https://lore.kernel.org/r/1579145333-1657-1-git-send-email-peter.chen@nxp.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/phy/phy.c

@@ -34,6 +34,14 @@ struct phy_devm {
 	struct notifier_block *nb;
 };
 
+static const char *const usb_chger_type[] = {
+	[UNKNOWN_TYPE]			= "USB_CHARGER_UNKNOWN_TYPE",
+	[SDP_TYPE]			= "USB_CHARGER_SDP_TYPE",
+	[CDP_TYPE]			= "USB_CHARGER_CDP_TYPE",
+	[DCP_TYPE]			= "USB_CHARGER_DCP_TYPE",
+	[ACA_TYPE]			= "USB_CHARGER_ACA_TYPE",
+};
+
 static struct usb_phy *__usb_find_phy(struct list_head *list,
 	enum usb_phy_type type)
 {
@@ -98,7 +106,8 @@ static void usb_phy_notify_charger_work(struct work_struct *work)
 {
 	struct usb_phy *usb_phy = container_of(work, struct usb_phy, chg_work);
 	char uchger_state[50] = { 0 };
-	char *envp[] = { uchger_state, NULL };
+	char uchger_type[50] = { 0 };
+	char *envp[] = { uchger_state, uchger_type, NULL };
 	unsigned int min, max;
 
 	switch (usb_phy->chg_state) {
@@ -122,6 +131,8 @@ static void usb_phy_notify_charger_work(struct work_struct *work)
 		return;
 	}
 
+	snprintf(uchger_type, ARRAY_SIZE(uchger_type),
+		 "USB_CHARGER_TYPE=%s", usb_chger_type[usb_phy->chg_type]);
 	kobject_uevent_env(&usb_phy->dev->kobj, KOBJ_CHANGE, envp);
 }