From 053a283ba95fdeefe16d5161b6db082d5ab28c26 Mon Sep 17 00:00:00 2001 From: Mark Kuo Date: Mon, 11 Jan 2016 17:49:16 +0800 Subject: [PATCH] CHROMIUM: usb: gadget: audio_source: add .free_func callback When userspace unbinds gadget functions through configfs, the .free_func() callback is always invoked. (in config_usb_cfg_unlink()) Implement it as a no-op to avoid the following crash: [ 68.125679] configfs-gadget gadget: unbind function 'accessory'/ffffffc0720bf000 [ 68.133202] configfs-gadget gadget: unbind function 'audio_source'/ffffffc0012ca3c0 [ 68.142668] tegra-xudc 700d0000.usb-device: ep 0 disabled [ 68.148186] Bad mode in Synchronous Abort handler detected, code 0x86000006 [ 68.155144] CPU: 2 PID: 1 Comm: init Tainted: G U W 3.18.0-09419-g87296c3-dirty #561 [ 68.163743] Hardware name: Google Tegra210 Smaug Rev 1,3+ (DT) [ 68.169566] task: ffffffc0bc8d0000 ti: ffffffc0bc8bc000 task.ti: ffffffc0bc8bc000 [ 68.177039] PC is at 0x0 [ 68.179577] LR is at usb_put_function+0x14/0x1c .... BUG=chrome-os-partner:49140 TEST="setprop sys.usb.config accessory,audio_source" on A44 and then switch back to default: "setprop sys.usb.config mtp,adb", no crash will be seen. Change-Id: I5b6141964aab861e86e3afb139ded02d4d122dab Signed-off-by: Mark Kuo Reviewed-on: https://chromium-review.googlesource.com/321013 Commit-Ready: Andrew Bresticker Tested-by: Andrew Bresticker Reviewed-by: Andrew Bresticker --- drivers/usb/gadget/function/f_audio_source.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/usb/gadget/function/f_audio_source.c b/drivers/usb/gadget/function/f_audio_source.c index 39645be93502..bcd817439dbf 100644 --- a/drivers/usb/gadget/function/f_audio_source.c +++ b/drivers/usb/gadget/function/f_audio_source.c @@ -583,6 +583,11 @@ static void audio_disable(struct usb_function *f) usb_ep_disable(audio->in_ep); } +static void audio_free_func(struct usb_function *f) +{ + /* no-op */ +} + /*-------------------------------------------------------------------------*/ static void audio_build_desc(struct audio_dev *audio) @@ -827,6 +832,7 @@ static struct audio_dev _audio_dev = { .set_alt = audio_set_alt, .setup = audio_setup, .disable = audio_disable, + .free_func = audio_free_func, }, .lock = __SPIN_LOCK_UNLOCKED(_audio_dev.lock), .idle_reqs = LIST_HEAD_INIT(_audio_dev.idle_reqs),