[media] cx231xx-audio: fix some locking issues

Acked-by: Sri Deevi <Srinivasa.Deevi@conexant.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2 files changed, 52 insertions, 51 deletions

diff --git a/drivers/media/video/cx231xx/cx231xx-audio.c b/drivers/media/video/cx231xx/cx231xx-audio.c
index 6ac418cc6895..30d13c15739a 100644
--- a/drivers/media/video/cx231xx/cx231xx-audio.c
+++ b/drivers/media/video/cx231xx/cx231xx-audio.c
@@ -124,6 +124,9 @@ static void cx231xx_audio_isocirq(struct urb *urb)
                 break;
         }
 
+        if (atomic_read(&dev->stream_started) == 0)
+                return;
+
         if (dev->adev.capture_pcm_substream) {
                 substream = dev->adev.capture_pcm_substream;
                 runtime = substream->runtime;
@@ -206,6 +209,9 @@ static void cx231xx_audio_bulkirq(struct urb *urb)
                 break;
         }
 
+        if (atomic_read(&dev->stream_started) == 0)
+                return;
+
         if (dev->adev.capture_pcm_substream) {
                 substream = dev->adev.capture_pcm_substream;
                 runtime = substream->runtime;
@@ -370,35 +376,6 @@ static int cx231xx_init_audio_bulk(struct cx231xx *dev)
         return errCode;
 }
 
-
-static int cx231xx_cmd(struct cx231xx *dev, int cmd, int arg)
-{
-        dprintk("%s transfer\n", (dev->adev.capture_stream == STREAM_ON) ?
-                "stop" : "start");
-
-        switch (cmd) {
-        case CX231XX_CAPTURE_STREAM_EN:
-                if (dev->adev.capture_stream == STREAM_OFF && arg == 1) {
-                        dev->adev.capture_stream = STREAM_ON;
-                        if (is_fw_load(dev) == 0)
-                                cx25840_call(dev, core, load_fw);
-                        if (dev->USE_ISO)
-                                cx231xx_init_audio_isoc(dev);
-                        else
-                                cx231xx_init_audio_bulk(dev);
-                } else if (dev->adev.capture_stream == STREAM_ON && arg == 0) {
-                        dev->adev.capture_stream = STREAM_OFF;
-                        cx231xx_isoc_audio_deinit(dev);
-                } else {
-                        cx231xx_errdev("An underrun very likely occurred. "
-                                       "Ignoring it.\n");
-                }
-                return 0;
-        default:
-                return -EINVAL;
-        }
-}
-
 static int snd_pcm_alloc_vmalloc_buffer(struct snd_pcm_substream *subs,
                                         size_t size)
 {
@@ -460,22 +437,24 @@ static int snd_cx231xx_capture_open(struct snd_pcm_substream *substream)
 
         /* set alternate setting for audio interface */
         /* 1 - 48000 samples per sec */
+        mutex_lock(&dev->lock);
         if (dev->USE_ISO)
                 ret = cx231xx_set_alt_setting(dev, INDEX_AUDIO, 1);
         else
                 ret = cx231xx_set_alt_setting(dev, INDEX_AUDIO, 0);
+        mutex_unlock(&dev->lock);
         if (ret < 0) {
                 cx231xx_errdev("failed to set alternate setting !\n");
 
                 return ret;
         }
 
-        /* inform hardware to start streaming */
-        ret = cx231xx_capture_start(dev, 1, Audio);
-
         runtime->hw = snd_cx231xx_hw_capture;
 
         mutex_lock(&dev->lock);
+        /* inform hardware to start streaming */
+        ret = cx231xx_capture_start(dev, 1, Audio);
+
         dev->adev.users++;
         mutex_unlock(&dev->lock);
 
@@ -493,7 +472,8 @@ static int snd_cx231xx_pcm_close(struct snd_pcm_substream *substream)
 
         dprintk("closing device\n");
 
-        /* inform hardware to start streaming */
+        /* inform hardware to stop streaming */
+        mutex_lock(&dev->lock);
         ret = cx231xx_capture_start(dev, 0, Audio);
 
         /* set alternate setting for audio interface */
@@ -502,11 +482,11 @@ static int snd_cx231xx_pcm_close(struct snd_pcm_substream *substream)
         if (ret < 0) {
                 cx231xx_errdev("failed to set alternate setting !\n");
 
+                mutex_unlock(&dev->lock);
                 return ret;
         }
 
         dev->mute = 1;
-        mutex_lock(&dev->lock);
         dev->adev.users--;
         mutex_unlock(&dev->lock);
 
@@ -515,7 +495,10 @@ static int snd_cx231xx_pcm_close(struct snd_pcm_substream *substream)
                 dprintk("disabling audio stream!\n");
                 dev->adev.shutdown = 0;
                 dprintk("released lock\n");
-                cx231xx_cmd(dev, CX231XX_CAPTURE_STREAM_EN, 0);
+                if (atomic_read(&dev->stream_started) > 0) {
+                        atomic_set(&dev->stream_started, 0);
+                        schedule_work(&dev->wq_trigger);
+                }
         }
         return 0;
 }
@@ -546,8 +529,10 @@ static int snd_cx231xx_hw_capture_free(struct snd_pcm_substream *substream)
 
         dprintk("Stop capture, if needed\n");
 
-        if (dev->adev.capture_stream == STREAM_ON)
-                cx231xx_cmd(dev, CX231XX_CAPTURE_STREAM_EN, CX231XX_STOP_AUDIO);
+        if (atomic_read(&dev->stream_started) > 0) {
+                atomic_set(&dev->stream_started, 0);
+                schedule_work(&dev->wq_trigger);
+        }
 
         return 0;
 }
@@ -562,32 +547,46 @@ static int snd_cx231xx_prepare(struct snd_pcm_substream *substream)
         return 0;
 }
 
+static void audio_trigger(struct work_struct *work)
+{
+        struct cx231xx *dev = container_of(work, struct cx231xx, wq_trigger);
+
+        if (atomic_read(&dev->stream_started)) {
+                dprintk("starting capture");
+                if (is_fw_load(dev) == 0)
+                        cx25840_call(dev, core, load_fw);
+                if (dev->USE_ISO)
+                        cx231xx_init_audio_isoc(dev);
+                else
+                        cx231xx_init_audio_bulk(dev);
+        } else {
+                dprintk("stopping capture");
+                cx231xx_isoc_audio_deinit(dev);
+        }
+}
+
 static int snd_cx231xx_capture_trigger(struct snd_pcm_substream *substream,
                                        int cmd)
 {
         struct cx231xx *dev = snd_pcm_substream_chip(substream);
         int retval;
 
-        dprintk("Should %s capture\n", (cmd == SNDRV_PCM_TRIGGER_START) ?
-                "start" : "stop");
-
         spin_lock(&dev->adev.slock);
         switch (cmd) {
         case SNDRV_PCM_TRIGGER_START:
-                cx231xx_cmd(dev, CX231XX_CAPTURE_STREAM_EN,
-                            CX231XX_START_AUDIO);
-                retval = 0;
+                atomic_set(&dev->stream_started, 1);
                 break;
         case SNDRV_PCM_TRIGGER_STOP:
-                cx231xx_cmd(dev, CX231XX_CAPTURE_STREAM_EN, CX231XX_STOP_AUDIO);
-                retval = 0;
+                atomic_set(&dev->stream_started, 0);
                 break;
         default:
                 retval = -EINVAL;
         }
-
         spin_unlock(&dev->adev.slock);
-        return retval;
+
+        schedule_work(&dev->wq_trigger);
+
+        return 0;
 }
 
 static snd_pcm_uframes_t snd_cx231xx_capture_pointer(struct snd_pcm_substream
@@ -668,6 +667,8 @@ static int cx231xx_audio_init(struct cx231xx *dev)
         strcpy(card->shortname, "Cx231xx Audio");
         strcpy(card->longname, "Conexant cx231xx Audio");
 
+        INIT_WORK(&dev->wq_trigger, audio_trigger);
+
         err = snd_card_register(card);
         if (err < 0) {
                 snd_card_free(card);
diff --git a/drivers/media/video/cx231xx/cx231xx.h b/drivers/media/video/cx231xx/cx231xx.h
index d0794332114c..f9cdc01a7faa 100644
--- a/drivers/media/video/cx231xx/cx231xx.h
+++ b/drivers/media/video/cx231xx/cx231xx.h
@@ -27,6 +27,7 @@
 #include <linux/ioctl.h>
 #include <linux/i2c.h>
 #include <linux/i2c-algo-bit.h>
+#include <linux/workqueue.h>
 #include <linux/mutex.h>
 
 #include <media/cx2341x.h>
@@ -387,9 +388,6 @@ enum AUDIO_INPUT {
 #define CX231XX_AUDIO_BUFS              5
 #define CX231XX_NUM_AUDIO_PACKETS       16
 #define CX231XX_ISO_NUM_AUDIO_PACKETS   64
-#define CX231XX_CAPTURE_STREAM_EN       1
-#define CX231XX_STOP_AUDIO              0
-#define CX231XX_START_AUDIO             1
 
 /* cx231xx extensions */
 #define CX231XX_AUDIO                   0x10
@@ -407,7 +405,6 @@ struct cx231xx_audio {
         struct snd_card *sndcard;
 
         int users, shutdown;
-        enum cx231xx_stream_state capture_stream;
         /* locks */
         spinlock_t slock;
 
@@ -624,6 +621,9 @@ struct cx231xx {
 
         struct cx231xx_IR *ir;
 
+        struct work_struct wq_trigger;          /* Trigger to start/stop audio for alsa module */
+        atomic_t           stream_started;      /* stream should be running if true */
+
         struct list_head devlist;
 
         int tuner_type;         /* type of the tuner */