ALSA: line6: Use guard() for mutex locks

Replace the manual mutex lock/unlock pairs with guard() for code
simplification.  The core code of line6_pcm_release() is factored out,
so that it can be covered by guard() nicely, too.

Only code refactoring, and no behavior change.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://patch.msgid.link/20250829150724.6886-7-tiwai@suse.de

diff --git a/sound/usb/line6/driver.c b/sound/usb/line6/driver.c
index f2f9261489a214883546f5904790a706f1faf445..c505c1cba1623364d316045d9166f1c9ff56ffdc 100644 (file)
--- a/sound/usb/line6/driver.c
+++ b/sound/usb/line6/driver.c
@@ -628,16 +628,12 @@ line6_hwdep_write(struct snd_hwdep *hwdep, const char __user *data, long count,
 static __poll_t
 line6_hwdep_poll(struct snd_hwdep *hwdep, struct file *file, poll_table *wait)
 {
-       __poll_t rv;
        struct usb_line6 *line6 = hwdep->private_data;
 
        poll_wait(file, &line6->messages.wait_queue, wait);
 
-       mutex_lock(&line6->messages.read_lock);
-       rv = kfifo_len(&line6->messages.fifo) == 0 ? 0 : EPOLLIN | EPOLLRDNORM;
-       mutex_unlock(&line6->messages.read_lock);
-
-       return rv;
+       guard(mutex)(&line6->messages.read_lock);
+       return kfifo_len(&line6->messages.fifo) == 0 ? 0 : EPOLLIN | EPOLLRDNORM;
 }
 
 static const struct snd_hwdep_ops hwdep_ops = {

diff --git a/sound/usb/line6/pcm.c b/sound/usb/line6/pcm.c
index c1e2a8ab66fac58492a118d9be9b8805f16681b2..81e6d5e05135ad3944f7c67525f683048dd43541 100644 (file)
--- a/sound/usb/line6/pcm.c
+++ b/sound/usb/line6/pcm.c
@@ -295,6 +295,28 @@ snd_pcm_uframes_t snd_line6_pointer(struct snd_pcm_substream *substream)
        return pstr->pos_done;
 }
 
+/* Stop and release duplex streams */
+static void __line6_pcm_release(struct snd_line6_pcm *line6pcm, int type)
+{
+       struct line6_pcm_stream *pstr;
+       int dir;
+
+       for (dir = 0; dir < 2; dir++)
+               line6_stream_stop(line6pcm, dir, type);
+       for (dir = 0; dir < 2; dir++) {
+               pstr = get_stream(line6pcm, dir);
+               line6_buffer_release(line6pcm, pstr, type);
+       }
+}
+
+/* Stop and release duplex streams */
+void line6_pcm_release(struct snd_line6_pcm *line6pcm, int type)
+{
+       guard(mutex)(&line6pcm->state_mutex);
+       __line6_pcm_release(line6pcm, type);
+}
+EXPORT_SYMBOL_GPL(line6_pcm_release);
+
 /* Acquire and optionally start duplex streams:
  * type is either LINE6_STREAM_IMPULSE or LINE6_STREAM_MONITOR
  */
@@ -304,7 +326,7 @@ int line6_pcm_acquire(struct snd_line6_pcm *line6pcm, int type, bool start)
        int ret = 0, dir;
 
        /* TODO: We should assert SNDRV_PCM_STREAM_PLAYBACK/CAPTURE == 0/1 */
-       mutex_lock(&line6pcm->state_mutex);
+       guard(mutex)(&line6pcm->state_mutex);
        for (dir = 0; dir < 2; dir++) {
                pstr = get_stream(line6pcm, dir);
                ret = line6_buffer_acquire(line6pcm, pstr, dir, type);
@@ -321,30 +343,12 @@ int line6_pcm_acquire(struct snd_line6_pcm *line6pcm, int type, bool start)
                }
        }
  error:
-       mutex_unlock(&line6pcm->state_mutex);
        if (ret < 0)
-               line6_pcm_release(line6pcm, type);
+               __line6_pcm_release(line6pcm, type);
        return ret;
 }
 EXPORT_SYMBOL_GPL(line6_pcm_acquire);
 
-/* Stop and release duplex streams */
-void line6_pcm_release(struct snd_line6_pcm *line6pcm, int type)
-{
-       struct line6_pcm_stream *pstr;
-       int dir;
-
-       mutex_lock(&line6pcm->state_mutex);
-       for (dir = 0; dir < 2; dir++)
-               line6_stream_stop(line6pcm, dir, type);
-       for (dir = 0; dir < 2; dir++) {
-               pstr = get_stream(line6pcm, dir);
-               line6_buffer_release(line6pcm, pstr, type);
-       }
-       mutex_unlock(&line6pcm->state_mutex);
-}
-EXPORT_SYMBOL_GPL(line6_pcm_release);
-
 /* common PCM hw_params callback */
 int snd_line6_hw_params(struct snd_pcm_substream *substream,
                        struct snd_pcm_hw_params *hw_params)
@@ -353,16 +357,14 @@ int snd_line6_hw_params(struct snd_pcm_substream *substream,
        struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
        struct line6_pcm_stream *pstr = get_stream(line6pcm, substream->stream);
 
-       mutex_lock(&line6pcm->state_mutex);
+       guard(mutex)(&line6pcm->state_mutex);
        ret = line6_buffer_acquire(line6pcm, pstr, substream->stream,
                                   LINE6_STREAM_PCM);
        if (ret < 0)
-               goto error;
+               return ret;
 
        pstr->period = params_period_bytes(hw_params);
- error:
-       mutex_unlock(&line6pcm->state_mutex);
-       return ret;
+       return 0;
 }
 
 /* common PCM hw_free callback */
@@ -371,9 +373,8 @@ int snd_line6_hw_free(struct snd_pcm_substream *substream)
        struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
        struct line6_pcm_stream *pstr = get_stream(line6pcm, substream->stream);
 
-       mutex_lock(&line6pcm->state_mutex);
+       guard(mutex)(&line6pcm->state_mutex);
        line6_buffer_release(line6pcm, pstr, LINE6_STREAM_PCM);
-       mutex_unlock(&line6pcm->state_mutex);
        return 0;
 }
 
@@ -588,7 +589,7 @@ int snd_line6_prepare(struct snd_pcm_substream *substream)
        struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
        struct line6_pcm_stream *pstr = get_stream(line6pcm, substream->stream);
 
-       mutex_lock(&line6pcm->state_mutex);
+       guard(mutex)(&line6pcm->state_mutex);
        if (!pstr->running)
                line6_wait_clear_audio_urbs(line6pcm, pstr);
 
@@ -602,6 +603,5 @@ int snd_line6_prepare(struct snd_pcm_substream *substream)
                line6pcm->in.bytes = 0;
        }
 
-       mutex_unlock(&line6pcm->state_mutex);
        return 0;
 }