Add patch to fix USB audio regression (rhbz 851619)

2 files changed, 139 insertions, 1 deletions

diff --git a/0001-ALSA-snd-usb-Fix-URB-cancellation-at-stream-start.patch b/0001-ALSA-snd-usb-Fix-URB-cancellation-at-stream-start.patch
new file mode 100644
index 000000000..031888c3c
--- /dev/null
+++ b/0001-ALSA-snd-usb-Fix-URB-cancellation-at-stream-start.patch
@@ -0,0 +1,131 @@
+From 42ff3e2d34427dc4c6faa09052a2531f2e71d7d6 Mon Sep 17 00:00:00 2001
+From: Daniel Mack <zonque@gmail.com>
+Date: Wed, 29 Aug 2012 13:17:05 +0200
+Subject: [PATCH] ALSA: snd-usb: Fix URB cancellation at stream start
+
+Commit e9ba389c5 ("ALSA: usb-audio: Fix scheduling-while-atomic bug in
+PCM capture stream") fixed a scheduling-while-atomic bug that happened
+when snd_usb_endpoint_start was called from the trigger callback, which
+is an atmic context. However, the patch breaks the idea of the endpoints
+reference counting, which is the reason why the driver has been
+refactored lately.
+
+Revert that commit and let snd_usb_endpoint_start() take care of the URB
+cancellation again. As this function is called from both atomic and
+non-atomic context, add a flag to denote whether the function may sleep.
+
+Signed-off-by: Daniel Mack <zonque@gmail.com>
+Cc: stable@kernel.org [3.5+]
+---
+ sound/usb/endpoint.c | 11 +++++++++--
+ sound/usb/endpoint.h |  2 +-
+ sound/usb/pcm.c      | 13 +++++--------
+ 3 files changed, 15 insertions(+), 11 deletions(-)
+
+diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c
+index c411812..b896c55 100644
+--- a/sound/usb/endpoint.c
++++ b/sound/usb/endpoint.c
+@@ -799,7 +799,9 @@ int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
+ /**
+  * snd_usb_endpoint_start: start an snd_usb_endpoint
+  *
+- * @ep: the endpoint to start
++ * @ep:		the endpoint to start
++ * @can_sleep:	flag indicating whether the operation is executed in
++ * 		non-atomic context
+  *
+  * A call to this function will increment the use count of the endpoint.
+  * In case it is not already running, the URBs for this endpoint will be
+@@ -809,7 +811,7 @@ int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
+  *
+  * Returns an error if the URB submission failed, 0 in all other cases.
+  */
+-int snd_usb_endpoint_start(struct snd_usb_endpoint *ep)
++int snd_usb_endpoint_start(struct snd_usb_endpoint *ep, int can_sleep)
+ {
+ 	int err;
+ 	unsigned int i;
+@@ -821,6 +823,11 @@ int snd_usb_endpoint_start(struct snd_usb_endpoint *ep)
+ 	if (++ep->use_count != 1)
+ 		return 0;
+ 
++	/* just to be sure */
++	deactivate_urbs(ep, 0, can_sleep);
++	if (can_sleep)
++		wait_clear_urbs(ep);
++
+ 	ep->active_mask = 0;
+ 	ep->unlink_mask = 0;
+ 	ep->phase = 0;
+diff --git a/sound/usb/endpoint.h b/sound/usb/endpoint.h
+index ee2723f..a8e60c1 100644
+--- a/sound/usb/endpoint.h
++++ b/sound/usb/endpoint.h
+@@ -13,7 +13,7 @@ int snd_usb_endpoint_set_params(struct snd_usb_endpoint *ep,
+ 				struct audioformat *fmt,
+ 				struct snd_usb_endpoint *sync_ep);
+ 
+-int  snd_usb_endpoint_start(struct snd_usb_endpoint *ep);
++int  snd_usb_endpoint_start(struct snd_usb_endpoint *ep, int can_sleep);
+ void snd_usb_endpoint_stop(struct snd_usb_endpoint *ep,
+ 			   int force, int can_sleep, int wait);
+ int  snd_usb_endpoint_activate(struct snd_usb_endpoint *ep);
+diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c
+index 62ec808..1546577 100644
+--- a/sound/usb/pcm.c
++++ b/sound/usb/pcm.c
+@@ -212,7 +212,7 @@ int snd_usb_init_pitch(struct snd_usb_audio *chip, int iface,
+ 	}
+ }
+ 
+-static int start_endpoints(struct snd_usb_substream *subs)
++static int start_endpoints(struct snd_usb_substream *subs, int can_sleep)
+ {
+ 	int err;
+ 
+@@ -225,7 +225,7 @@ static int start_endpoints(struct snd_usb_substream *subs)
+ 		snd_printdd(KERN_DEBUG "Starting data EP @%p\n", ep);
+ 
+ 		ep->data_subs = subs;
+-		err = snd_usb_endpoint_start(ep);
++		err = snd_usb_endpoint_start(ep, can_sleep);
+ 		if (err < 0) {
+ 			clear_bit(SUBSTREAM_FLAG_DATA_EP_STARTED, &subs->flags);
+ 			return err;
+@@ -239,7 +239,7 @@ static int start_endpoints(struct snd_usb_substream *subs)
+ 		snd_printdd(KERN_DEBUG "Starting sync EP @%p\n", ep);
+ 
+ 		ep->sync_slave = subs->data_endpoint;
+-		err = snd_usb_endpoint_start(ep);
++		err = snd_usb_endpoint_start(ep, can_sleep);
+ 		if (err < 0) {
+ 			clear_bit(SUBSTREAM_FLAG_SYNC_EP_STARTED, &subs->flags);
+ 			return err;
+@@ -544,13 +544,10 @@ static int snd_usb_pcm_prepare(struct snd_pcm_substream *substream)
+ 	subs->last_frame_number = 0;
+ 	runtime->delay = 0;
+ 
+-	/* clear the pending deactivation on the target EPs */
+-	deactivate_endpoints(subs);
+-
+ 	/* for playback, submit the URBs now; otherwise, the first hwptr_done
+ 	 * updates for all URBs would happen at the same time when starting */
+ 	if (subs->direction == SNDRV_PCM_STREAM_PLAYBACK)
+-		return start_endpoints(subs);
++		return start_endpoints(subs, 1);
+ 
+ 	return 0;
+ }
+@@ -1175,7 +1172,7 @@ static int snd_usb_substream_capture_trigger(struct snd_pcm_substream *substream
+ 
+ 	switch (cmd) {
+ 	case SNDRV_PCM_TRIGGER_START:
+-		err = start_endpoints(subs);
++		err = start_endpoints(subs, 0);
+ 		if (err < 0)
+ 			return err;
+ 
+-- 
+1.7.11.4
+
diff --git a/kernel.spec b/kernel.spec
index d7a4c1aa3..187e2e2cb 100644
--- a/kernel.spec
+++ b/kernel.spec
@@ -62,7 +62,7 @@ Summary: The Linux kernel
 # For non-released -rc kernels, this will be appended after the rcX and
 # gitX tags, so a 3 here would become part of release "0.rcX.gitX.3"
 #
-%global baserelease 1
+%global baserelease 2
 %global fedora_build %{baserelease}
 
 # base_sublevel is the kernel version we're starting with and patching
@@ -753,6 +753,8 @@ Patch22066: virtio-scsi-Initialize-scatterlist-structure.patch
 #rhbz 846037
 Patch22067: selinux-Fix-sel_netnode_insert-suspicious-rcu-dereference.patch
 
+Patch30000: 0001-ALSA-snd-usb-Fix-URB-cancellation-at-stream-start.patch
+
 # END OF PATCH DEFINITIONS
 
 %endif
@@ -1449,6 +1451,8 @@ ApplyPatch virtio-scsi-Initialize-scatterlist-structure.patch
 #rhbz 846037
 ApplyPatch selinux-Fix-sel_netnode_insert-suspicious-rcu-dereference.patch
 
+ApplyPatch 0001-ALSA-snd-usb-Fix-URB-cancellation-at-stream-start.patch
+
 # END OF PATCH APPLICATIONS
 
 %endif
@@ -2311,6 +2315,9 @@ fi
 #                 ||----w |
 #                 ||     ||
 %changelog
+* Wed Aug 29 2012 Josh Boyer <jwboyer@redhat.com> - 3.6.0-0.rc3.git3.2
+- Add patch to fix USB audio regression (rhbz 851619)
+
 * Wed Aug 29 2012 Josh Boyer <jwboyer@redhat.com> - 3.6.0-0.rc3.git3.1
 - Linux v3.6-rc3-207-g318e151