From: Erik Gilling <konkers@android.com>
Date: Tue, 9 Aug 2011 21:18:21 +0000 (-0700)
Subject: usb: otg: add proxy_wait handler to otg_id
X-Git-Tag: firefly_0821_release~7613^2~363
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=e65d9fe5564afaca75ae657179446578be73e9ba;p=firefly-linux-kernel-4.4.55.git

usb: otg: add proxy_wait handler to otg_id

Some otg_id handlers can detect what's connected but can't detect a change.
This allows that handler to pass off the waiting for ID change to a proxy.

Change-Id: Ib38b750c3da4bffc35e37b620ecee37c5d64d31f
Signed-off-by: Erik Gilling <konkers@android.com>
---

diff --git a/drivers/usb/otg/otg_id.c b/drivers/usb/otg/otg_id.c
index 2398b1a951d4..ce22b4621308 100644
--- a/drivers/usb/otg/otg_id.c
+++ b/drivers/usb/otg/otg_id.c
@@ -44,16 +44,24 @@ static void __otg_id_notify(void)
 {
 	int ret;
 	struct otg_id_notifier_block *otg_id_nb;
-
+	bool proxy_wait = false;
 	if (plist_head_empty(&otg_id_plist))
 		return;
 
 	plist_for_each_entry(otg_id_nb, &otg_id_plist, p) {
-		ret = otg_id_nb->detect(otg_id_nb);
+		if (proxy_wait) {
+			if (otg_id_nb->proxy_wait)
+				ret = otg_id_nb->proxy_wait(otg_id_nb);
+		} else {
+			ret = otg_id_nb->detect(otg_id_nb);
+		}
 		if (ret == OTG_ID_HANDLED) {
 			otg_id_active = otg_id_nb;
 			return;
 		}
+		if (ret == OTG_ID_PROXY_WAIT)
+			proxy_wait = true;
+
 	}
 
 	WARN(1, "otg id event not handled");
diff --git a/include/linux/usb/otg_id.h b/include/linux/usb/otg_id.h
index b686ab067957..46a44637c117 100644
--- a/include/linux/usb/otg_id.h
+++ b/include/linux/usb/otg_id.h
@@ -28,6 +28,10 @@
  *    get called first.
  * @detect: Called during otg_id_notify.  Return OTG_ID_HANDLED if the USB cable
  *    has been identified
+ * @proxy_wait: Called during otg_id_notify if a previous handler returns
+ *    OTG_ID_PROXY_WAIT.  This should wait on ID change then call otg_id_notify.
+ *    This is used when a handler knows what's connected but can't detect
+ *    the change itself.
  * @cancel: Called after detect has returned OTG_ID_HANDLED to ask it to
  *    release detection resources to allow a new identification to occur.
  */
@@ -35,10 +39,12 @@
 struct otg_id_notifier_block {
 	int priority;
 	int (*detect)(struct otg_id_notifier_block *otg_id_nb);
+	int (*proxy_wait)(struct otg_id_notifier_block *otg_id_nb);
 	void (*cancel)(struct otg_id_notifier_block *otg_id_nb);
 	struct plist_node p;
 };
 
+#define OTG_ID_PROXY_WAIT 2
 #define OTG_ID_HANDLED 1
 #define OTG_ID_UNHANDLED 0