Merge branch 'topic/kerneldoc' into for-next

Documentation/DocBook/alsa-driver-api.tmpl

@@ -57,7 +57,7 @@
 !Esound/core/pcm.c
 !Esound/core/pcm_lib.c
 !Esound/core/pcm_native.c
-!include/sound/pcm.h
+!Iinclude/sound/pcm.h
      </sect1>
      <sect1><title>PCM Format Helpers</title>
 !Esound/core/pcm_misc.c
@@ -104,13 +104,30 @@
 !Iinclude/sound/compress_driver.h
      </sect1>
   </chapter>
+  <chapter><title>ASoC</title>
+     <sect1><title>ASoC Core API</title>
+!Iinclude/sound/soc.h
+!Esound/soc/soc-core.c
+!Esound/soc/soc-cache.c
+!Esound/soc/soc-devres.c
+!Esound/soc/soc-io.c
+!Esound/soc/soc-pcm.c
+     </sect1>
+     <sect1><title>ASoC DAPM API</title>
+!Esound/soc/soc-dapm.c
+     </sect1>
+     <sect1><title>ASoC DMA Engine API</title>
+!Esound/soc/soc-generic-dmaengine-pcm.c
+     </sect1>
+  </chapter>
   <chapter><title>Miscellaneous Functions</title>
      <sect1><title>Hardware-Dependent Devices API</title>
 !Esound/core/hwdep.c
      </sect1>
      <sect1><title>Jack Abstraction Layer API</title>
-!Esound/core/jack.c
 !Iinclude/sound/jack.h
+!Esound/core/jack.c
+!Esound/soc/soc-jack.c
      </sect1>
      <sect1><title>ISA DMA Helpers</title>
 !Esound/core/isadma.c

include/sound/pcm.h

@@ -533,6 +533,12 @@ snd_pcm_debug_name(struct snd_pcm_substream *substream, char *buf, size_t size)
  *  PCM library
  */
 
+/**
+ * snd_pcm_stream_linked - Check whether the substream is linked with others
+ * @substream: substream to check
+ *
+ * Returns true if the given substream is being linked with others.
+ */
 static inline int snd_pcm_stream_linked(struct snd_pcm_substream *substream)
 {
 	return substream->group != &substream->self_group;
@@ -543,6 +549,16 @@ void snd_pcm_stream_unlock(struct snd_pcm_substream *substream);
 void snd_pcm_stream_lock_irq(struct snd_pcm_substream *substream);
 void snd_pcm_stream_unlock_irq(struct snd_pcm_substream *substream);
 unsigned long _snd_pcm_stream_lock_irqsave(struct snd_pcm_substream *substream);
+
+/**
+ * snd_pcm_stream_lock_irqsave - Lock the PCM stream
+ * @substream: PCM substream
+ * @flags: irq flags
+ *
+ * This locks the PCM stream like snd_pcm_stream_lock() but with the local
+ * IRQ (only when nonatomic is false).  In nonatomic case, this is identical
+ * as snd_pcm_stream_lock().
+ */
 #define snd_pcm_stream_lock_irqsave(substream, flags)		 \
 	do {							 \
 		typecheck(unsigned long, flags);		 \
@@ -551,9 +567,25 @@ unsigned long _snd_pcm_stream_lock_irqsave(struct snd_pcm_substream *substream);
 void snd_pcm_stream_unlock_irqrestore(struct snd_pcm_substream *substream,
 				      unsigned long flags);
 
+/**
+ * snd_pcm_group_for_each_entry - iterate over the linked substreams
+ * @s: the iterator
+ * @substream: the substream
+ *
+ * Iterate over the all linked substreams to the given @substream.
+ * When @substream isn't linked with any others, this gives returns @substream
+ * itself once.
+ */
 #define snd_pcm_group_for_each_entry(s, substream) \
 	list_for_each_entry(s, &substream->group->substreams, link_list)
 
+/**
+ * snd_pcm_running - Check whether the substream is in a running state
+ * @substream: substream to check
+ *
+ * Returns true if the given substream is in the state RUNNING, or in the
+ * state DRAINING for playback.
+ */
 static inline int snd_pcm_running(struct snd_pcm_substream *substream)
 {
 	return (substream->runtime->status->state == SNDRV_PCM_STATE_RUNNING ||
@@ -561,45 +593,81 @@ static inline int snd_pcm_running(struct snd_pcm_substream *substream)
 		 substream->stream == SNDRV_PCM_STREAM_PLAYBACK));
 }
 
+/**
+ * bytes_to_samples - Unit conversion of the size from bytes to samples
+ * @runtime: PCM runtime instance
+ * @size: size in bytes
+ */
 static inline ssize_t bytes_to_samples(struct snd_pcm_runtime *runtime, ssize_t size)
 {
 	return size * 8 / runtime->sample_bits;
 }
 
+/**
+ * bytes_to_frames - Unit conversion of the size from bytes to frames
+ * @runtime: PCM runtime instance
+ * @size: size in bytes
+ */
 static inline snd_pcm_sframes_t bytes_to_frames(struct snd_pcm_runtime *runtime, ssize_t size)
 {
 	return size * 8 / runtime->frame_bits;
 }
 
+/**
+ * samples_to_bytes - Unit conversion of the size from samples to bytes
+ * @runtime: PCM runtime instance
+ * @size: size in samples
+ */
 static inline ssize_t samples_to_bytes(struct snd_pcm_runtime *runtime, ssize_t size)
 {
 	return size * runtime->sample_bits / 8;
 }
 
+/**
+ * frames_to_bytes - Unit conversion of the size from frames to bytes
+ * @runtime: PCM runtime instance
+ * @size: size in frames
+ */
 static inline ssize_t frames_to_bytes(struct snd_pcm_runtime *runtime, snd_pcm_sframes_t size)
 {
 	return size * runtime->frame_bits / 8;
 }
 
+/**
+ * frame_aligned - Check whether the byte size is aligned to frames
+ * @runtime: PCM runtime instance
+ * @bytes: size in bytes
+ */
 static inline int frame_aligned(struct snd_pcm_runtime *runtime, ssize_t bytes)
 {
 	return bytes % runtime->byte_align == 0;
 }
 
+/**
+ * snd_pcm_lib_buffer_bytes - Get the buffer size of the current PCM in bytes
+ * @substream: PCM substream
+ */
 static inline size_t snd_pcm_lib_buffer_bytes(struct snd_pcm_substream *substream)
 {
 	struct snd_pcm_runtime *runtime = substream->runtime;
 	return frames_to_bytes(runtime, runtime->buffer_size);
 }
 
+/**
+ * snd_pcm_lib_period_bytes - Get the period size of the current PCM in bytes
+ * @substream: PCM substream
+ */
 static inline size_t snd_pcm_lib_period_bytes(struct snd_pcm_substream *substream)
 {
 	struct snd_pcm_runtime *runtime = substream->runtime;
 	return frames_to_bytes(runtime, runtime->period_size);
 }
 
-/*
- *  result is: 0 ... (boundary - 1)
+/**
+ * snd_pcm_playback_avail - Get the available (writable) space for playback
+ * @runtime: PCM runtime instance
+ *
+ * Result is between 0 ... (boundary - 1)
  */
 static inline snd_pcm_uframes_t snd_pcm_playback_avail(struct snd_pcm_runtime *runtime)
 {
@@ -611,8 +679,11 @@ static inline snd_pcm_uframes_t snd_pcm_playback_avail(struct snd_pcm_runtime *r
 	return avail;
 }
 
-/*
- *  result is: 0 ... (boundary - 1)
+/**
+ * snd_pcm_playback_avail - Get the available (readable) space for capture
+ * @runtime: PCM runtime instance
+ *
+ * Result is between 0 ... (boundary - 1)
  */
 static inline snd_pcm_uframes_t snd_pcm_capture_avail(struct snd_pcm_runtime *runtime)
 {
@@ -622,11 +693,19 @@ static inline snd_pcm_uframes_t snd_pcm_capture_avail(struct snd_pcm_runtime *ru
 	return avail;
 }
 
+/**
+ * snd_pcm_playback_hw_avail - Get the queued space for playback
+ * @runtime: PCM runtime instance
+ */
 static inline snd_pcm_sframes_t snd_pcm_playback_hw_avail(struct snd_pcm_runtime *runtime)
 {
 	return runtime->buffer_size - snd_pcm_playback_avail(runtime);
 }
 
+/**
+ * snd_pcm_capture_hw_avail - Get the free space for capture
+ * @runtime: PCM runtime instance
+ */
 static inline snd_pcm_sframes_t snd_pcm_capture_hw_avail(struct snd_pcm_runtime *runtime)
 {
 	return runtime->buffer_size - snd_pcm_capture_avail(runtime);
@@ -706,6 +785,20 @@ static inline int snd_pcm_capture_empty(struct snd_pcm_substream *substream)
 	return snd_pcm_capture_avail(runtime) == 0;
 }
 
+/**
+ * snd_pcm_trigger_done - Mark the master substream
+ * @substream: the pcm substream instance
+ * @master: the linked master substream
+ *
+ * When multiple substreams of the same card are linked and the hardware
+ * supports the single-shot operation, the driver calls this in the loop
+ * in snd_pcm_group_for_each_entry() for marking the substream as "done".
+ * Then most of trigger operations are performed only to the given master
+ * substream.
+ *
+ * The trigger_master mark is cleared at timestamp updates at the end
+ * of trigger operations.
+ */
 static inline void snd_pcm_trigger_done(struct snd_pcm_substream *substream, 
 					struct snd_pcm_substream *master)
 {
@@ -748,18 +841,59 @@ static inline const struct snd_interval *hw_param_interval_c(const struct snd_pc
 	return &params->intervals[var - SNDRV_PCM_HW_PARAM_FIRST_INTERVAL];
 }
 
-#define params_channels(p) \
-	(hw_param_interval_c((p), SNDRV_PCM_HW_PARAM_CHANNELS)->min)
-#define params_rate(p) \
-	(hw_param_interval_c((p), SNDRV_PCM_HW_PARAM_RATE)->min)
-#define params_period_size(p) \
-	(hw_param_interval_c((p), SNDRV_PCM_HW_PARAM_PERIOD_SIZE)->min)
-#define params_periods(p) \
-	(hw_param_interval_c((p), SNDRV_PCM_HW_PARAM_PERIODS)->min)
-#define params_buffer_size(p) \
-	(hw_param_interval_c((p), SNDRV_PCM_HW_PARAM_BUFFER_SIZE)->min)
-#define params_buffer_bytes(p) \
-	(hw_param_interval_c((p), SNDRV_PCM_HW_PARAM_BUFFER_BYTES)->min)
+/**
+ * params_channels - Get the number of channels from the hw params
+ * @p: hw params
+ */
+static inline unsigned int params_channels(const struct snd_pcm_hw_params *p)
+{
+	return hw_param_interval_c(p, SNDRV_PCM_HW_PARAM_CHANNELS)->min;
+}
+
+/**
+ * params_channels - Get the sample rate from the hw params
+ * @p: hw params
+ */
+static inline unsigned int params_rate(const struct snd_pcm_hw_params *p)
+{
+	return hw_param_interval_c(p, SNDRV_PCM_HW_PARAM_RATE)->min;
+}
+
+/**
+ * params_channels - Get the period size (in frames) from the hw params
+ * @p: hw params
+ */
+static inline unsigned int params_period_size(const struct snd_pcm_hw_params *p)
+{
+	return hw_param_interval_c(p, SNDRV_PCM_HW_PARAM_PERIOD_SIZE)->min;
+}
+
+/**
+ * params_channels - Get the number of periods from the hw params
+ * @p: hw params
+ */
+static inline unsigned int params_periods(const struct snd_pcm_hw_params *p)
+{
+	return hw_param_interval_c(p, SNDRV_PCM_HW_PARAM_PERIODS)->min;
+}
+
+/**
+ * params_channels - Get the buffer size (in frames) from the hw params
+ * @p: hw params
+ */
+static inline unsigned int params_buffer_size(const struct snd_pcm_hw_params *p)
+{
+	return hw_param_interval_c(p, SNDRV_PCM_HW_PARAM_BUFFER_SIZE)->min;
+}
+
+/**
+ * params_channels - Get the buffer size (in bytes) from the hw params
+ * @p: hw params
+ */
+static inline unsigned int params_buffer_bytes(const struct snd_pcm_hw_params *p)
+{
+	return hw_param_interval_c(p, SNDRV_PCM_HW_PARAM_BUFFER_BYTES)->min;
+}
 
 int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v);
 void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c);
@@ -881,6 +1015,14 @@ unsigned int snd_pcm_rate_bit_to_rate(unsigned int rate_bit);
 unsigned int snd_pcm_rate_mask_intersect(unsigned int rates_a,
 					 unsigned int rates_b);
 
+/**
+ * snd_pcm_set_runtime_buffer - Set the PCM runtime buffer
+ * @substream: PCM substream to set
+ * @bufp: the buffer information, NULL to clear
+ *
+ * Copy the buffer information to runtime->dma_buffer when @bufp is non-NULL.
+ * Otherwise it clears the current buffer information.
+ */
 static inline void snd_pcm_set_runtime_buffer(struct snd_pcm_substream *substream,
 					      struct snd_dma_buffer *bufp)
 {
@@ -906,6 +1048,11 @@ void snd_pcm_timer_resolution_change(struct snd_pcm_substream *substream);
 void snd_pcm_timer_init(struct snd_pcm_substream *substream);
 void snd_pcm_timer_done(struct snd_pcm_substream *substream);
 
+/**
+ * snd_pcm_gettime - Fill the timespec depending on the timestamp mode
+ * @runtime: PCM runtime instance
+ * @tv: timespec to fill
+ */
 static inline void snd_pcm_gettime(struct snd_pcm_runtime *runtime,
 				   struct timespec *tv)
 {
@@ -942,7 +1089,6 @@ int _snd_pcm_lib_alloc_vmalloc_buffer(struct snd_pcm_substream *substream,
 int snd_pcm_lib_free_vmalloc_buffer(struct snd_pcm_substream *substream);
 struct page *snd_pcm_lib_get_vmalloc_page(struct snd_pcm_substream *substream,
 					  unsigned long offset);
-#if 0 /* for kernel-doc */
 /**
  * snd_pcm_lib_alloc_vmalloc_buffer - allocate virtual DMA buffer
  * @substream: the substream to allocate the buffer to
@@ -955,8 +1101,13 @@ struct page *snd_pcm_lib_get_vmalloc_page(struct snd_pcm_substream *substream,
  * Return: 1 if the buffer was changed, 0 if not changed, or a negative error
  * code.
  */
-static int snd_pcm_lib_alloc_vmalloc_buffer
-			(struct snd_pcm_substream *substream, size_t size);
+static inline int snd_pcm_lib_alloc_vmalloc_buffer
+			(struct snd_pcm_substream *substream, size_t size)
+{
+	return _snd_pcm_lib_alloc_vmalloc_buffer(substream, size,
+						 GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO);
+}
+
 /**
  * snd_pcm_lib_alloc_vmalloc_32_buffer - allocate 32-bit-addressable buffer
  * @substream: the substream to allocate the buffer to
@@ -968,15 +1119,12 @@ static int snd_pcm_lib_alloc_vmalloc_buffer
  * Return: 1 if the buffer was changed, 0 if not changed, or a negative error
  * code.
  */
-static int snd_pcm_lib_alloc_vmalloc_32_buffer
-			(struct snd_pcm_substream *substream, size_t size);
-#endif
-#define snd_pcm_lib_alloc_vmalloc_buffer(subs, size) \
-	_snd_pcm_lib_alloc_vmalloc_buffer \
-			(subs, size, GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO)
-#define snd_pcm_lib_alloc_vmalloc_32_buffer(subs, size) \
-	_snd_pcm_lib_alloc_vmalloc_buffer \
-			(subs, size, GFP_KERNEL | GFP_DMA32 | __GFP_ZERO)
+static inline int snd_pcm_lib_alloc_vmalloc_32_buffer
+			(struct snd_pcm_substream *substream, size_t size)
+{
+	return _snd_pcm_lib_alloc_vmalloc_buffer(substream, size,
+						 GFP_KERNEL | GFP_DMA32 | __GFP_ZERO);
+}
 
 #define snd_pcm_get_dma_buf(substream) ((substream)->runtime->dma_buffer_p)
 
@@ -996,18 +1144,35 @@ struct page *snd_pcm_sgbuf_ops_page(struct snd_pcm_substream *substream,
 #define snd_pcm_sgbuf_ops_page	NULL
 #endif /* SND_DMA_SGBUF */
 
+/**
+ * snd_pcm_sgbuf_get_addr - Get the DMA address at the corresponding offset
+ * @substream: PCM substream
+ * @ofs: byte offset
+ */
 static inline dma_addr_t
 snd_pcm_sgbuf_get_addr(struct snd_pcm_substream *substream, unsigned int ofs)
 {
 	return snd_sgbuf_get_addr(snd_pcm_get_dma_buf(substream), ofs);
 }
 
+/**
+ * snd_pcm_sgbuf_get_ptr - Get the virtual address at the corresponding offset
+ * @substream: PCM substream
+ * @ofs: byte offset
+ */
 static inline void *
 snd_pcm_sgbuf_get_ptr(struct snd_pcm_substream *substream, unsigned int ofs)
 {
 	return snd_sgbuf_get_ptr(snd_pcm_get_dma_buf(substream), ofs);
 }
 
+/**
+ * snd_pcm_sgbuf_chunk_size - Compute the max size that fits within the contig.
+ * page from the given size
+ * @substream: PCM substream
+ * @ofs: byte offset
+ * @size: byte size to examine
+ */
 static inline unsigned int
 snd_pcm_sgbuf_get_chunk_size(struct snd_pcm_substream *substream,
 			     unsigned int ofs, unsigned int size)
@@ -1015,13 +1180,24 @@ snd_pcm_sgbuf_get_chunk_size(struct snd_pcm_substream *substream,
 	return snd_sgbuf_get_chunk_size(snd_pcm_get_dma_buf(substream), ofs, size);
 }
 
-/* handle mmap counter - PCM mmap callback should handle this counter properly */
+/**
+ * snd_pcm_mmap_data_open - increase the mmap counter
+ * @area: VMA
+ *
+ * PCM mmap callback should handle this counter properly
+ */
 static inline void snd_pcm_mmap_data_open(struct vm_area_struct *area)
 {
 	struct snd_pcm_substream *substream = (struct snd_pcm_substream *)area->vm_private_data;
 	atomic_inc(&substream->mmap_count);
 }
 
+/**
+ * snd_pcm_mmap_data_close - decrease the mmap counter
+ * @area: VMA
+ *
+ * PCM mmap callback should handle this counter properly
+ */
 static inline void snd_pcm_mmap_data_close(struct vm_area_struct *area)
 {
 	struct snd_pcm_substream *substream = (struct snd_pcm_substream *)area->vm_private_data;
@@ -1041,6 +1217,11 @@ int snd_pcm_lib_mmap_iomem(struct snd_pcm_substream *substream, struct vm_area_s
 
 #define snd_pcm_lib_mmap_vmalloc NULL
 
+/**
+ * snd_pcm_limit_isa_dma_size - Get the max size fitting with ISA DMA transfer
+ * @dma: DMA number
+ * @max: pointer to store the max size
+ */
 static inline void snd_pcm_limit_isa_dma_size(int dma, size_t *max)
 {
 	*max = dma < 4 ? 64 * 1024 : 128 * 1024;
@@ -1093,7 +1274,11 @@ struct snd_pcm_chmap {
 	void *private_data;	/* optional: private data pointer */
 };
 
-/* get the PCM substream assigned to the given chmap info */
+/**
+ * snd_pcm_chmap_substream - get the PCM substream assigned to the given chmap info
+ * @info: chmap information
+ * @idx: the substream number index
+ */
 static inline struct snd_pcm_substream *
 snd_pcm_chmap_substream(struct snd_pcm_chmap *info, unsigned int idx)
 {
@@ -1120,7 +1305,10 @@ int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream,
 			   unsigned long private_value,
 			   struct snd_pcm_chmap **info_ret);
 
-/* Strong-typed conversion of pcm_format to bitwise */
+/**
+ * pcm_format_to_bits - Strong-typed conversion of pcm_format to bitwise
+ * @pcm_format: PCM format
+ */
 static inline u64 pcm_format_to_bits(snd_pcm_format_t pcm_format)
 {
 	return 1ULL << (__force int) pcm_format;

sound/core/control.c

@@ -141,6 +141,16 @@ static int snd_ctl_release(struct inode *inode, struct file *file)
 	return 0;
 }
 
+/**
+ * snd_ctl_notify - Send notification to user-space for a control change
+ * @card: the card to send notification
+ * @mask: the event mask, SNDRV_CTL_EVENT_*
+ * @id: the ctl element id to send notification
+ *
+ * This function adds an event record with the given id and mask, appends
+ * to the list and wakes up the user-space for notification.  This can be
+ * called in the atomic context.
+ */
 void snd_ctl_notify(struct snd_card *card, unsigned int mask,
 		    struct snd_ctl_elem_id *id)
 {
@@ -179,7 +189,6 @@ void snd_ctl_notify(struct snd_card *card, unsigned int mask,
 	}
 	read_unlock(&card->ctl_files_rwlock);
 }
-
 EXPORT_SYMBOL(snd_ctl_notify);
 
 /**
@@ -261,7 +270,6 @@ struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new *ncontrol,
 	kctl.private_data = private_data;
 	return snd_ctl_new(&kctl, access);
 }
-
 EXPORT_SYMBOL(snd_ctl_new1);
 
 /**
@@ -280,7 +288,6 @@ void snd_ctl_free_one(struct snd_kcontrol *kcontrol)
 		kfree(kcontrol);
 	}
 }
-
 EXPORT_SYMBOL(snd_ctl_free_one);
 
 static bool snd_ctl_remove_numid_conflict(struct snd_card *card,
@@ -376,7 +383,6 @@ int snd_ctl_add(struct snd_card *card, struct snd_kcontrol *kcontrol)
 	snd_ctl_free_one(kcontrol);
 	return err;
 }
-
 EXPORT_SYMBOL(snd_ctl_add);
 
 /**
@@ -471,7 +477,6 @@ int snd_ctl_remove(struct snd_card *card, struct snd_kcontrol *kcontrol)
 	snd_ctl_free_one(kcontrol);
 	return 0;
 }
-
 EXPORT_SYMBOL(snd_ctl_remove);
 
 /**
@@ -499,7 +504,6 @@ int snd_ctl_remove_id(struct snd_card *card, struct snd_ctl_elem_id *id)
 	up_write(&card->controls_rwsem);
 	return ret;
 }
-
 EXPORT_SYMBOL(snd_ctl_remove_id);
 
 /**
@@ -617,7 +621,6 @@ int snd_ctl_rename_id(struct snd_card *card, struct snd_ctl_elem_id *src_id,
 	up_write(&card->controls_rwsem);
 	return 0;
 }
-
 EXPORT_SYMBOL(snd_ctl_rename_id);
 
 /**
@@ -645,7 +648,6 @@ struct snd_kcontrol *snd_ctl_find_numid(struct snd_card *card, unsigned int numi
 	}
 	return NULL;
 }
-
 EXPORT_SYMBOL(snd_ctl_find_numid);
 
 /**
@@ -687,7 +689,6 @@ struct snd_kcontrol *snd_ctl_find_id(struct snd_card *card,
 	}
 	return NULL;
 }
-
 EXPORT_SYMBOL(snd_ctl_find_id);
 
 static int snd_ctl_card_info(struct snd_card *card, struct snd_ctl_file * ctl,
@@ -1526,19 +1527,28 @@ static int _snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn, struct list_head *
 	return 0;
 }
 
+/**
+ * snd_ctl_register_ioctl - register the device-specific control-ioctls
+ * @fcn: ioctl callback function
+ *
+ * called from each device manager like pcm.c, hwdep.c, etc.
+ */
 int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn)
 {
 	return _snd_ctl_register_ioctl(fcn, &snd_control_ioctls);
 }
-
 EXPORT_SYMBOL(snd_ctl_register_ioctl);
 
 #ifdef CONFIG_COMPAT
+/**
+ * snd_ctl_register_ioctl_compat - register the device-specific 32bit compat
+ * control-ioctls
+ * @fcn: ioctl callback function
+ */
 int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn)
 {
 	return _snd_ctl_register_ioctl(fcn, &snd_control_compat_ioctls);
 }
-
 EXPORT_SYMBOL(snd_ctl_register_ioctl_compat);
 #endif
 
@@ -1566,19 +1576,26 @@ static int _snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn,
 	return -EINVAL;
 }
 
+/**
+ * snd_ctl_unregister_ioctl - de-register the device-specific control-ioctls
+ * @fcn: ioctl callback function to unregister
+ */
 int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn)
 {
 	return _snd_ctl_unregister_ioctl(fcn, &snd_control_ioctls);
 }
-
 EXPORT_SYMBOL(snd_ctl_unregister_ioctl);
 
 #ifdef CONFIG_COMPAT
+/**
+ * snd_ctl_unregister_ioctl - de-register the device-specific compat 32bit
+ * control-ioctls
+ * @fcn: ioctl callback function to unregister
+ */
 int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn)
 {
 	return _snd_ctl_unregister_ioctl(fcn, &snd_control_compat_ioctls);
 }
-
 EXPORT_SYMBOL(snd_ctl_unregister_ioctl_compat);
 #endif
 
@@ -1702,6 +1719,16 @@ int snd_ctl_create(struct snd_card *card)
 /*
  * Frequently used control callbacks/helpers
  */
+
+/**
+ * snd_ctl_boolean_mono_info - Helper function for a standard boolean info
+ * callback with a mono channel
+ * @kcontrol: the kcontrol instance
+ * @uinfo: info to store
+ *
+ * This is a function that can be used as info callback for a standard
+ * boolean control with a single mono channel.
+ */
 int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol,
 			      struct snd_ctl_elem_info *uinfo)
 {
@@ -1711,9 +1738,17 @@ int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol,
 	uinfo->value.integer.max = 1;
 	return 0;
 }
-
 EXPORT_SYMBOL(snd_ctl_boolean_mono_info);
 
+/**
+ * snd_ctl_boolean_stereo_info - Helper function for a standard boolean info
+ * callback with stereo two channels
+ * @kcontrol: the kcontrol instance
+ * @uinfo: info to store
+ *
+ * This is a function that can be used as info callback for a standard
+ * boolean control with stereo two channels.
+ */
 int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol,
 				struct snd_ctl_elem_info *uinfo)
 {
@@ -1723,7 +1758,6 @@ int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol,
 	uinfo->value.integer.max = 1;
 	return 0;
 }
-
 EXPORT_SYMBOL(snd_ctl_boolean_stereo_info);
 
 /**

sound/core/init.c

@@ -438,17 +438,6 @@ int snd_card_disconnect(struct snd_card *card)
 
 EXPORT_SYMBOL(snd_card_disconnect);
 
-/**
- *  snd_card_free - frees given soundcard structure
- *  @card: soundcard structure
- *
- *  This function releases the soundcard structure and the all assigned
- *  devices automatically.  That is, you don't have to release the devices
- *  by yourself.
- *
- *  Return: Zero. Frees all associated devices and frees the control
- *  interface associated to given soundcard.
- */
 static int snd_card_do_free(struct snd_card *card)
 {
 #if IS_ENABLED(CONFIG_SND_MIXER_OSS)
@@ -469,6 +458,15 @@ static int snd_card_do_free(struct snd_card *card)
 	return 0;
 }
 
+/**
+ * snd_card_free_when_closed - Disconnect the card, free it later eventually
+ * @card: soundcard structure
+ *
+ * Unlike snd_card_free(), this function doesn't try to release the card
+ * resource immediately, but tries to disconnect at first.  When the card
+ * is still in use, the function returns before freeing the resources.
+ * The card resources will be freed when the refcount gets to zero.
+ */
 int snd_card_free_when_closed(struct snd_card *card)
 {
 	int ret = snd_card_disconnect(card);
@@ -479,6 +477,19 @@ int snd_card_free_when_closed(struct snd_card *card)
 }
 EXPORT_SYMBOL(snd_card_free_when_closed);
 
+/**
+ * snd_card_free - frees given soundcard structure
+ * @card: soundcard structure
+ *
+ * This function releases the soundcard structure and the all assigned
+ * devices automatically.  That is, you don't have to release the devices
+ * by yourself.
+ *
+ * This function waits until the all resources are properly released.
+ *
+ * Return: Zero. Frees all associated devices and frees the control
+ * interface associated to given soundcard.
+ */
 int snd_card_free(struct snd_card *card)
 {
 	struct completion released;

sound/core/pcm.c

@@ -218,6 +218,10 @@ static char *snd_pcm_format_names[] = {
 	FORMAT(DSD_U32_LE),
 };
 
+/**
+ * snd_pcm_format_name - Return a name string for the given PCM format
+ * @format: PCM format
+ */
 const char *snd_pcm_format_name(snd_pcm_format_t format)
 {
 	if ((__force unsigned int)format >= ARRAY_SIZE(snd_pcm_format_names))
@@ -707,7 +711,6 @@ int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count)
 	}
 	return 0;
 }				
-
 EXPORT_SYMBOL(snd_pcm_new_stream);
 
 static int _snd_pcm_new(struct snd_card *card, const char *id, int device,
@@ -1155,6 +1158,15 @@ static int snd_pcm_dev_disconnect(struct snd_device *device)
 	return 0;
 }
 
+/**
+ * snd_pcm_notify - Add/remove the notify list
+ * @notify: PCM notify list
+ * @nfree: 0 = register, 1 = unregister
+ *
+ * This adds the given notifier to the global list so that the callback is
+ * called for each registered PCM devices.  This exists only for PCM OSS
+ * emulation, so far.
+ */
 int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree)
 {
 	struct snd_pcm *pcm;
@@ -1177,7 +1189,6 @@ int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree)
 	mutex_unlock(&register_mutex);
 	return 0;
 }
-
 EXPORT_SYMBOL(snd_pcm_notify);
 
 #ifdef CONFIG_PROC_FS

sound/core/pcm_native.c

@@ -74,6 +74,14 @@ static int snd_pcm_open(struct file *file, struct snd_pcm *pcm, int stream);
 static DEFINE_RWLOCK(snd_pcm_link_rwlock);
 static DECLARE_RWSEM(snd_pcm_link_rwsem);
 
+/**
+ * snd_pcm_stream_lock - Lock the PCM stream
+ * @substream: PCM substream
+ *
+ * This locks the PCM stream's spinlock or mutex depending on the nonatomic
+ * flag of the given substream.  This also takes the global link rw lock
+ * (or rw sem), too, for avoiding the race with linked streams.
+ */
 void snd_pcm_stream_lock(struct snd_pcm_substream *substream)
 {
 	if (substream->pcm->nonatomic) {
@@ -86,6 +94,12 @@ void snd_pcm_stream_lock(struct snd_pcm_substream *substream)
 }
 EXPORT_SYMBOL_GPL(snd_pcm_stream_lock);
 
+/**
+ * snd_pcm_stream_lock - Unlock the PCM stream
+ * @substream: PCM substream
+ *
+ * This unlocks the PCM stream that has been locked via snd_pcm_stream_lock().
+ */
 void snd_pcm_stream_unlock(struct snd_pcm_substream *substream)
 {
 	if (substream->pcm->nonatomic) {
@@ -98,6 +112,14 @@ void snd_pcm_stream_unlock(struct snd_pcm_substream *substream)
 }
 EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock);
 
+/**
+ * snd_pcm_stream_lock_irq - Lock the PCM stream
+ * @substream: PCM substream
+ *
+ * This locks the PCM stream like snd_pcm_stream_lock() and disables the local
+ * IRQ (only when nonatomic is false).  In nonatomic case, this is identical
+ * as snd_pcm_stream_lock().
+ */
 void snd_pcm_stream_lock_irq(struct snd_pcm_substream *substream)
 {
 	if (!substream->pcm->nonatomic)
@@ -106,6 +128,12 @@ void snd_pcm_stream_lock_irq(struct snd_pcm_substream *substream)
 }
 EXPORT_SYMBOL_GPL(snd_pcm_stream_lock_irq);
 
+/**
+ * snd_pcm_stream_unlock_irq - Unlock the PCM stream
+ * @substream: PCM substream
+ *
+ * This is a counter-part of snd_pcm_stream_lock_irq().
+ */
 void snd_pcm_stream_unlock_irq(struct snd_pcm_substream *substream)
 {
 	snd_pcm_stream_unlock(substream);
@@ -124,6 +152,13 @@ unsigned long _snd_pcm_stream_lock_irqsave(struct snd_pcm_substream *substream)
 }
 EXPORT_SYMBOL_GPL(_snd_pcm_stream_lock_irqsave);
 
+/**
+ * snd_pcm_stream_unlock_irqrestore - Unlock the PCM stream
+ * @substream: PCM substream
+ * @flags: irq flags
+ *
+ * This is a counter-part of snd_pcm_stream_lock_irqsave().
+ */
 void snd_pcm_stream_unlock_irqrestore(struct snd_pcm_substream *substream,
 				      unsigned long flags)
 {
@@ -3312,6 +3347,15 @@ static const struct vm_operations_struct snd_pcm_vm_ops_data_fault = {
 /*
  * mmap the DMA buffer on RAM
  */
+
+/**
+ * snd_pcm_lib_default_mmap - Default PCM data mmap function
+ * @substream: PCM substream
+ * @area: VMA
+ *
+ * This is the default mmap handler for PCM data.  When mmap pcm_ops is NULL,
+ * this function is invoked implicitly.
+ */
 int snd_pcm_lib_default_mmap(struct snd_pcm_substream *substream,
 			     struct vm_area_struct *area)
 {
@@ -3343,6 +3387,15 @@ EXPORT_SYMBOL_GPL(snd_pcm_lib_default_mmap);
  * mmap the DMA buffer on I/O memory area
  */
 #if SNDRV_PCM_INFO_MMAP_IOMEM
+/**
+ * snd_pcm_lib_mmap_iomem - Default PCM data mmap function for I/O mem
+ * @substream: PCM substream
+ * @area: VMA
+ *
+ * When your hardware uses the iomapped pages as the hardware buffer and
+ * wants to mmap it, pass this function as mmap pcm_ops.  Note that this
+ * is supposed to work only on limited architectures.
+ */
 int snd_pcm_lib_mmap_iomem(struct snd_pcm_substream *substream,
 			   struct vm_area_struct *area)
 {

sound/core/sound.c

@@ -355,8 +355,13 @@ int snd_unregister_device(int type, struct snd_card *card, int dev)
 
 EXPORT_SYMBOL(snd_unregister_device);
 
-/* get the assigned device to the given type and device number;
- * the caller needs to release it via put_device() after using it
+/**
+ * snd_get_device - get the assigned device to the given type and device number
+ * @type: the device type, SNDRV_DEVICE_TYPE_XXX
+ * @card:the card instance
+ * @dev: the device index
+ *
+ * The caller needs to release it via put_device() after using it.
  */
 struct device *snd_get_device(int type, struct snd_card *card, int dev)
 {

sound/pci/hda/hda_generic.c

@@ -40,7 +40,12 @@
 #include "hda_generic.h"
 
 
-/* initialize hda_gen_spec struct */
+/**
+ * snd_hda_gen_spec_init - initialize hda_gen_spec struct
+ * @spec: hda_gen_spec object to initialize
+ *
+ * Initialize the given hda_gen_spec object.
+ */
 int snd_hda_gen_spec_init(struct hda_gen_spec *spec)
 {
 	snd_array_init(&spec->kctls, sizeof(struct snd_kcontrol_new), 32);
@@ -51,6 +56,17 @@ int snd_hda_gen_spec_init(struct hda_gen_spec *spec)
 }
 EXPORT_SYMBOL_GPL(snd_hda_gen_spec_init);
 
+/**
+ * snd_hda_gen_add_kctl - Add a new kctl_new struct from the template
+ * @spec: hda_gen_spec object
+ * @name: name string to override the template, NULL if unchanged
+ * @temp: template for the new kctl
+ *
+ * Add a new kctl (actually snd_kcontrol_new to be instantiated later)
+ * element based on the given snd_kcontrol_new template @temp and the
+ * name string @name to the list in @spec.
+ * Returns the newly created object or NULL as error.
+ */
 struct snd_kcontrol_new *
 snd_hda_gen_add_kctl(struct hda_gen_spec *spec, const char *name,
 		     const struct snd_kcontrol_new *temp)
@@ -259,8 +275,14 @@ static struct nid_path *get_nid_path(struct hda_codec *codec,
 	return NULL;
 }
 
-/* get the path between the given NIDs;
- * passing 0 to either @pin or @dac behaves as a wildcard
+/**
+ * snd_hda_get_nid_path - get the path between the given NIDs
+ * @codec: the HDA codec
+ * @from_nid: the NID where the path start from
+ * @to_nid: the NID where the path ends at
+ *
+ * Return the found nid_path object or NULL for error.
+ * Passing 0 to either @from_nid or @to_nid behaves as a wildcard.
  */
 struct nid_path *snd_hda_get_nid_path(struct hda_codec *codec,
 				      hda_nid_t from_nid, hda_nid_t to_nid)
@@ -269,8 +291,14 @@ struct nid_path *snd_hda_get_nid_path(struct hda_codec *codec,
 }
 EXPORT_SYMBOL_GPL(snd_hda_get_nid_path);
 
-/* get the index number corresponding to the path instance;
- * the index starts from 1, for easier checking the invalid value
+/**
+ * snd_hda_get_path_idx - get the index number corresponding to the path
+ * instance
+ * @codec: the HDA codec
+ * @path: nid_path object
+ *
+ * The returned index starts from 1, i.e. the actual array index with offset 1,
+ * and zero is handled as an invalid path
  */
 int snd_hda_get_path_idx(struct hda_codec *codec, struct nid_path *path)
 {
@@ -287,7 +315,12 @@ int snd_hda_get_path_idx(struct hda_codec *codec, struct nid_path *path)
 }
 EXPORT_SYMBOL_GPL(snd_hda_get_path_idx);
 
-/* get the path instance corresponding to the given index number */
+/**
+ * snd_hda_get_path_from_idx - get the path instance corresponding to the
+ * given index number
+ * @codec: the HDA codec
+ * @idx: the path index
+ */
 struct nid_path *snd_hda_get_path_from_idx(struct hda_codec *codec, int idx)
 {
 	struct hda_gen_spec *spec = codec->spec;
@@ -415,7 +448,18 @@ static bool __parse_nid_path(struct hda_codec *codec,
 	return true;
 }
 
-/* parse the widget path from the given nid to the target nid;
+/**
+ * snd_hda_parse_nid_path - parse the widget path from the given nid to
+ * the target nid
+ * @codec: the HDA codec
+ * @from_nid: the NID where the path start from
+ * @to_nid: the NID where the path ends at
+ * @anchor_nid: the anchor indication
+ * @path: the path object to store the result
+ *
+ * Returns true if a matching path is found.
+ *
+ * The parsing behavior depends on parameters:
  * when @from_nid is 0, try to find an empty DAC;
  * when @anchor_nid is set to a positive value, only paths through the widget
  * with the given value are evaluated.
@@ -436,9 +480,15 @@ bool snd_hda_parse_nid_path(struct hda_codec *codec, hda_nid_t from_nid,
 }
 EXPORT_SYMBOL_GPL(snd_hda_parse_nid_path);
 
-/*
- * parse the path between the given NIDs and add to the path list.
- * if no valid path is found, return NULL
+/**
+ * snd_hda_add_new_path - parse the path between the given NIDs and
+ * add to the path list
+ * @codec: the HDA codec
+ * @from_nid: the NID where the path start from
+ * @to_nid: the NID where the path ends at
+ * @anchor_nid: the anchor indication, see snd_hda_parse_nid_path()
+ *
+ * If no valid path is found, returns NULL.
  */
 struct nid_path *
 snd_hda_add_new_path(struct hda_codec *codec, hda_nid_t from_nid,
@@ -724,8 +774,14 @@ static void activate_amp_in(struct hda_codec *codec, struct nid_path *path,
 	}
 }
 
-/* activate or deactivate the given path
- * if @add_aamix is set, enable the input from aa-mix NID as well (if any)
+/**
+ * snd_hda_activate_path - activate or deactivate the given path
+ * @codec: the HDA codec
+ * @path: the path to activate/deactivate
+ * @enable: flag to activate or not
+ * @add_aamix: enable the input from aamix NID
+ *
+ * If @add_aamix is set, enable the input from aa-mix NID as well (if any).
  */
 void snd_hda_activate_path(struct hda_codec *codec, struct nid_path *path,
 			   bool enable, bool add_aamix)
@@ -3883,7 +3939,12 @@ static void do_automute(struct hda_codec *codec, int num_pins, hda_nid_t *pins,
 	}
 }
 
-/* Toggle outputs muting */
+/**
+ * snd_hda_gen_update_outputs - Toggle outputs muting
+ * @codec: the HDA codec
+ *
+ * Update the mute status of all outputs based on the current jack states.
+ */
 void snd_hda_gen_update_outputs(struct hda_codec *codec)
 {
 	struct hda_gen_spec *spec = codec->spec;
@@ -3944,7 +4005,11 @@ static void call_update_outputs(struct hda_codec *codec)
 		snd_ctl_sync_vmaster(spec->vmaster_mute.sw_kctl, false);
 }
 
-/* standard HP-automute helper */
+/**
+ * snd_hda_gen_hp_automute - standard HP-automute helper
+ * @codec: the HDA codec
+ * @jack: jack object, NULL for the whole
+ */
 void snd_hda_gen_hp_automute(struct hda_codec *codec,
 			     struct hda_jack_callback *jack)
 {
@@ -3965,7 +4030,11 @@ void snd_hda_gen_hp_automute(struct hda_codec *codec,
 }
 EXPORT_SYMBOL_GPL(snd_hda_gen_hp_automute);
 
-/* standard line-out-automute helper */
+/**
+ * snd_hda_gen_line_automute - standard line-out-automute helper
+ * @codec: the HDA codec
+ * @jack: jack object, NULL for the whole
+ */
 void snd_hda_gen_line_automute(struct hda_codec *codec,
 			       struct hda_jack_callback *jack)
 {
@@ -3986,7 +4055,11 @@ void snd_hda_gen_line_automute(struct hda_codec *codec,
 }
 EXPORT_SYMBOL_GPL(snd_hda_gen_line_automute);
 
-/* standard mic auto-switch helper */
+/**
+ * snd_hda_gen_mic_autoswitch - standard mic auto-switch helper
+ * @codec: the HDA codec
+ * @jack: jack object, NULL for the whole
+ */
 void snd_hda_gen_mic_autoswitch(struct hda_codec *codec,
 				struct hda_jack_callback *jack)
 {
@@ -4318,7 +4391,13 @@ static int check_auto_mic_availability(struct hda_codec *codec)
 	return 0;
 }
 
-/* power_filter hook; make inactive widgets into power down */
+/**
+ * snd_hda_gen_path_power_filter - power_filter hook to make inactive widgets
+ * into power down
+ * @codec: the HDA codec
+ * @nid: NID to evalute
+ * @power_state: target power state
+ */
 unsigned int snd_hda_gen_path_power_filter(struct hda_codec *codec,
 						  hda_nid_t nid,
 						  unsigned int power_state)
@@ -4354,8 +4433,11 @@ static void mute_all_mixer_nid(struct hda_codec *codec, hda_nid_t mix)
 	}
 }
 
-/*
- * Parse the given BIOS configuration and set up the hda_gen_spec
+/**
+ * snd_hda_gen_parse_auto_config - Parse the given BIOS configuration and
+ * set up the hda_gen_spec
+ * @codec: the HDA codec
+ * @cfg: Parsed pin configuration
  *
  * return 1 if successful, 0 if the proper config is not found,
  * or a negative error code
@@ -4541,6 +4623,12 @@ static const char * const slave_pfxs[] = {
 	NULL,
 };
 
+/**
+ * snd_hda_gen_build_controls - Build controls from the parsed results
+ * @codec: the HDA codec
+ *
+ * Pass this to build_controls patch_ops.
+ */
 int snd_hda_gen_build_controls(struct hda_codec *codec)
 {
 	struct hda_gen_spec *spec = codec->spec;
@@ -5018,7 +5106,12 @@ static void fill_pcm_stream_name(char *str, size_t len, const char *sfx,
 	strlcat(str, sfx, len);
 }
 
-/* build PCM streams based on the parsed results */
+/**
+ * snd_hda_gen_build_pcms - build PCM streams based on the parsed results
+ * @codec: the HDA codec
+ *
+ * Pass this to build_pcms patch_ops.
+ */
 int snd_hda_gen_build_pcms(struct hda_codec *codec)
 {
 	struct hda_gen_spec *spec = codec->spec;
@@ -5313,9 +5406,11 @@ static void clear_unsol_on_unused_pins(struct hda_codec *codec)
 	}
 }
 
-/*
- * initialize the generic spec;
- * this can be put as patch_ops.init function
+/**
+ * snd_hda_gen_init - initialize the generic spec
+ * @codec: the HDA codec
+ *
+ * This can be put as patch_ops init function.
  */
 int snd_hda_gen_init(struct hda_codec *codec)
 {
@@ -5351,9 +5446,11 @@ int snd_hda_gen_init(struct hda_codec *codec)
 }
 EXPORT_SYMBOL_GPL(snd_hda_gen_init);
 
-/*
- * free the generic spec;
- * this can be put as patch_ops.free function
+/**
+ * snd_hda_gen_free - free the generic spec
+ * @codec: the HDA codec
+ *
+ * This can be put as patch_ops free function.
  */
 void snd_hda_gen_free(struct hda_codec *codec)
 {
@@ -5365,9 +5462,12 @@ void snd_hda_gen_free(struct hda_codec *codec)
 EXPORT_SYMBOL_GPL(snd_hda_gen_free);
 
 #ifdef CONFIG_PM
-/*
- * check the loopback power save state;
- * this can be put as patch_ops.check_power_status function
+/**
+ * snd_hda_gen_check_power_status - check the loopback power save state
+ * @codec: the HDA codec
+ * @nid: NID to inspect
+ *
+ * This can be put as patch_ops check_power_status function.
  */
 int snd_hda_gen_check_power_status(struct hda_codec *codec, hda_nid_t nid)
 {
@@ -5393,6 +5493,12 @@ static const struct hda_codec_ops generic_patch_ops = {
 #endif
 };
 
+/**
+ * snd_hda_parse_generic_codec - Generic codec parser
+ * @codec: the HDA codec
+ *
+ * This should be called from the HDA codec core.
+ */
 int snd_hda_parse_generic_codec(struct hda_codec *codec)
 {
 	struct hda_gen_spec *spec;