Commit 75e91fe9 authored Dec 18, 2013 by Manu Gautam

USB: android: Fix crash when F_FS gets descriptors before it is enabled



If F_FS (or ADB) function is selected in the composition, android
gadget driver keeps USB gadget disabled until it receives function
descriptors from userspace. This is signalled by F_FS when it calls
functionfs_ready_callback.
There could be a scenario (mainly due to userspace ignorance) that
before enabling F_FS (ADB) in the composition, descriptors are already
passed to F_FS. This results in a crash later on cable connection
in ffs_set_alt due to missing contexts initialization as functionfs_bind
never got called.

Fix this by calling functionfs_bind when F_FS is enabled by user and
it already has received the descriptors.

CRs-fixed: 585542
Change-Id: I52d680cdcd7f5d4a3eb90eb64785ea176c832849
Signed-off-by: Manu Gautam <mgautam@codeaurora.org>

parent 012fce15

drivers/usb/gadget/android.c

+12 −1

Original line number	Diff line number	Diff line
		@@ -444,12 +444,23 @@ static void ffs_function_enable(struct android_usb_function *f)
		{
		struct android_dev *dev = f->android_dev;
		struct functionfs_config *config = f->config;
		int ret = 0;

		config->enabled = true;

		/* Disable the gadget until the function is ready */
		if (!config->opened)
		if (!config->opened) {
		android_disable(dev);
		} else {
		/*
		* Call functionfs_bind to handle the case where userspace
		* passed descriptors before updating enabled functions list
		*/
		ret = functionfs_bind(config->data, dev->cdev);
		if (ret)
		pr_err("%s: functionfs_bind failed (%d)\n", __func__,
		ret);
		}
		}

		static void ffs_function_disable(struct android_usb_function *f)