ALSA: hda - Add comments and descriptions to CA0132 functions

Add comments and descriptions to functions.
Bump dsp_free_ports() to below dsp_allocate_ports_format() to group the
alloc functions together for commenting.

Signed-off-by: Ian Minett <ian_minett@creativelabs.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 163 insertions, 17 deletions

diff --git a/sound/pci/hda/patch_ca0132.c b/sound/pci/hda/patch_ca0132.c
index 4d8a7edfd308..a7b216ea9df3 100644
--- a/sound/pci/hda/patch_ca0132.c
+++ b/sound/pci/hda/patch_ca0132.c
@@ -519,6 +519,9 @@ static int chipio_write_data(struct hda_codec *codec, unsigned int data)
         return res;
 }
 
+/*
+ * Write multiple data through the vendor widget -- NOT protected by the Mutex!
+ */
 static int chipio_write_data_multiple(struct hda_codec *codec,
                                       const u32 *data,
                                       unsigned int count)
@@ -588,6 +591,10 @@ exit:
         return err;
 }
 
+/*
+ * Write multiple values to the given address through the chip I/O widget.
+ * protected by the Mutex
+ */
 static int chipio_write_multiple(struct hda_codec *codec,
                                  u32 chip_addx,
                                  const u32 *data,
@@ -634,6 +641,9 @@ exit:
         return err;
 }
 
+/*
+ * Set chip control flags through the chip I/O widget.
+ */
 static void chipio_set_control_flag(struct hda_codec *codec,
                                     enum control_flag_id flag_id,
                                     bool flag_state)
@@ -647,6 +657,9 @@ static void chipio_set_control_flag(struct hda_codec *codec,
                             VENDOR_CHIPIO_FLAG_SET, val);
 }
 
+/*
+ * Set chip parameters through the chip I/O widget.
+ */
 static void chipio_set_control_param(struct hda_codec *codec,
                 enum control_param_id param_id, int param_val)
 {
@@ -671,6 +684,9 @@ static void chipio_set_control_param(struct hda_codec *codec,
         }
 }
 
+/*
+ * Set sampling rate of the connection point.
+ */
 static void chipio_set_conn_rate(struct hda_codec *codec,
                                 int connid, enum ca0132_sample_rate rate)
 {
@@ -679,6 +695,9 @@ static void chipio_set_conn_rate(struct hda_codec *codec,
                                  rate);
 }
 
+/*
+ * Enable clocks.
+ */
 static void chipio_enable_clocks(struct hda_codec *codec)
 {
         struct ca0132_spec *spec = codec->spec;
@@ -718,6 +737,9 @@ static int dspio_send(struct hda_codec *codec, unsigned int reg,
         return -EIO;
 }
 
+/*
+ * Wait for DSP to be ready for commands
+ */
 static void dspio_write_wait(struct hda_codec *codec)
 {
         int cur_val, prv_val;
@@ -734,6 +756,9 @@ static void dspio_write_wait(struct hda_codec *codec)
         } while (cur_val && (cur_val == prv_val) && --retry);
 }
 
+/*
+ * Write SCP data to DSP
+ */
 static int dspio_write(struct hda_codec *codec, unsigned int scp_data)
 {
         struct ca0132_spec *spec = codec->spec;
@@ -762,6 +787,9 @@ error:
                         -EIO : 0;
 }
 
+/*
+ * Write multiple SCP data to DSP
+ */
 static int dspio_write_multiple(struct hda_codec *codec,
                                 unsigned int *buffer, unsigned int size)
 {
@@ -782,6 +810,9 @@ static int dspio_write_multiple(struct hda_codec *codec,
         return status;
 }
 
+/*
+ * Construct the SCP header using corresponding fields
+ */
 static inline unsigned int
 make_scp_header(unsigned int target_id, unsigned int source_id,
                 unsigned int get_flag, unsigned int req,
@@ -802,6 +833,9 @@ make_scp_header(unsigned int target_id, unsigned int source_id,
         return header;
 }
 
+/*
+ * Extract corresponding fields from SCP header
+ */
 static inline void
 extract_scp_header(unsigned int header,
                    unsigned int *target_id, unsigned int *source_id,
@@ -835,6 +869,9 @@ struct scp_msg {
         unsigned int data[SCP_MAX_DATA_WORDS];
 };
 
+/*
+ * Send SCP message to DSP
+ */
 static int dspio_send_scp_message(struct hda_codec *codec,
                                   unsigned char *send_buf,
                                   unsigned int send_buf_size,
@@ -912,6 +949,19 @@ static int dspio_send_scp_message(struct hda_codec *codec,
         return status;
 }
 
+/**
+ * Prepare and send the SCP message to DSP
+ * @codec: the HDA codec
+ * @mod_id: ID of the DSP module to send the command
+ * @req: ID of request to send to the DSP module
+ * @dir: SET or GET
+ * @data: pointer to the data to send with the request, request specific
+ * @len: length of the data, in bytes
+ * @reply: point to the buffer to hold data returned for a reply
+ * @reply_len: length of the reply buffer returned from GET
+ *
+ * Returns zero or a negative error code.
+ */
 static int dspio_scp(struct hda_codec *codec,
                 int mod_id, int req, int dir, void *data, unsigned int len,
                 void *reply, unsigned int *reply_len)
@@ -988,6 +1038,9 @@ static int dspio_scp(struct hda_codec *codec,
         return status;
 }
 
+/*
+ * Allocate a DSP DMA channel via an SCP message
+ */
 static int dspio_alloc_dma_chan(struct hda_codec *codec, unsigned int *dma_chan)
 {
         int status = 0;
@@ -1013,6 +1066,9 @@ static int dspio_alloc_dma_chan(struct hda_codec *codec, unsigned int *dma_chan)
         return status;
 }
 
+/*
+ * Free a DSP DMA via an SCP message
+ */
 static int dspio_free_dma_chan(struct hda_codec *codec, unsigned int dma_chan)
 {
         int status = 0;
@@ -1035,7 +1091,7 @@ static int dspio_free_dma_chan(struct hda_codec *codec, unsigned int dma_chan)
 }
 
 /*
- * CA0132 DSP access stuffs
+ * (Re)start the DSP
  */
 static int dsp_set_run_state(struct hda_codec *codec)
 {
@@ -1069,6 +1125,9 @@ static int dsp_set_run_state(struct hda_codec *codec)
         return 0;
 }
 
+/*
+ * Reset the DSP
+ */
 static int dsp_reset(struct hda_codec *codec)
 {
         unsigned int res;
@@ -1088,6 +1147,9 @@ static int dsp_reset(struct hda_codec *codec)
         return 0;
 }
 
+/*
+ * Convert chip address to DSP address
+ */
 static unsigned int dsp_chip_to_dsp_addx(unsigned int chip_addx,
                                         bool *code, bool *yram)
 {
@@ -1106,6 +1168,9 @@ static unsigned int dsp_chip_to_dsp_addx(unsigned int chip_addx,
         return (unsigned int)INVALID_CHIP_ADDRESS;
 }
 
+/*
+ * Check if the DSP DMA is active
+ */
 static bool dsp_is_dma_active(struct hda_codec *codec, unsigned int dma_chan)
 {
         unsigned int dma_chnlstart_reg;
@@ -1226,6 +1291,9 @@ static int dsp_dma_setup_common(struct hda_codec *codec,
         return 0;
 }
 
+/*
+ * Setup the DSP DMA per-transfer-specific registers
+ */
 static int dsp_dma_setup(struct hda_codec *codec,
                         unsigned int chip_addx,
                         unsigned int count,
@@ -1314,6 +1382,9 @@ static int dsp_dma_setup(struct hda_codec *codec,
         return 0;
 }
 
+/*
+ * Start the DSP DMA
+ */
 static int dsp_dma_start(struct hda_codec *codec,
                          unsigned int dma_chan, bool ovly)
 {
@@ -1347,6 +1418,9 @@ static int dsp_dma_start(struct hda_codec *codec,
         return status;
 }
 
+/*
+ * Stop the DSP DMA
+ */
 static int dsp_dma_stop(struct hda_codec *codec,
                         unsigned int dma_chan, bool ovly)
 {
@@ -1379,6 +1453,17 @@ static int dsp_dma_stop(struct hda_codec *codec,
         return status;
 }
 
+/**
+ * Allocate router ports
+ *
+ * @codec: the HDA codec
+ * @num_chans: number of channels in the stream
+ * @ports_per_channel: number of ports per channel
+ * @start_device: start device
+ * @port_map: pointer to the port list to hold the allocated ports
+ *
+ * Returns zero or a negative error code.
+ */
 static int dsp_allocate_router_ports(struct hda_codec *codec,
                                      unsigned int num_chans,
                                      unsigned int ports_per_channel,
@@ -1417,6 +1502,9 @@ static int dsp_allocate_router_ports(struct hda_codec *codec,
         return (res < 0) ? res : 0;
 }
 
+/*
+ * Free router ports
+ */
 static int dsp_free_router_ports(struct hda_codec *codec)
 {
         int status = 0;
@@ -1434,6 +1522,9 @@ static int dsp_free_router_ports(struct hda_codec *codec)
         return status;
 }
 
+/*
+ * Allocate DSP ports for the download stream
+ */
 static int dsp_allocate_ports(struct hda_codec *codec,
                         unsigned int num_chans,
                         unsigned int rate_multi, unsigned int *port_map)
@@ -1455,22 +1546,6 @@ static int dsp_allocate_ports(struct hda_codec *codec,
         return status;
 }
 
-static int dsp_free_ports(struct hda_codec *codec)
-{
-        int status;
-
-        snd_printdd(KERN_INFO "     dsp_free_ports() -- begin");
-
-        status = dsp_free_router_ports(codec);
-        if (status < 0) {
-                snd_printdd(KERN_ERR "free router ports fail");
-                return status;
-        }
-        snd_printdd(KERN_INFO "     dsp_free_ports() -- complete");
-
-        return status;
-}
-
 static int dsp_allocate_ports_format(struct hda_codec *codec,
                         const unsigned short fmt,
                         unsigned int *port_map)
@@ -1495,6 +1570,25 @@ static int dsp_allocate_ports_format(struct hda_codec *codec,
 }
 
 /*
+ * free DSP ports
+ */
+static int dsp_free_ports(struct hda_codec *codec)
+{
+        int status;
+
+        snd_printdd(KERN_INFO "     dsp_free_ports() -- begin");
+
+        status = dsp_free_router_ports(codec);
+        if (status < 0) {
+                snd_printdd(KERN_ERR "free router ports fail");
+                return status;
+        }
+        snd_printdd(KERN_INFO "     dsp_free_ports() -- complete");
+
+        return status;
+}
+
+/*
  *  HDA DMA engine stuffs for DSP code download
  */
 struct dma_engine {
@@ -1528,6 +1622,9 @@ static int dma_convert_to_hda_format(
         return 0;
 }
 
+/*
+ *  Reset DMA for DSP download
+ */
 static int dma_reset(struct dma_engine *dma)
 {
         struct hda_codec *codec = dma->codec;
@@ -1642,6 +1739,11 @@ static const struct dsp_image_seg *get_next_seg_ptr(
  */
 #define INVALID_DMA_CHANNEL (~0UL)
 
+/*
+ * Program a list of address/data pairs via the ChipIO widget.
+ * The segment data is in the format of successive pairs of words.
+ * These are repeated as indicated by the segment's count field.
+ */
 static int dspxfr_hci_write(struct hda_codec *codec,
                         const struct dsp_image_seg *fls)
 {
@@ -1668,6 +1770,21 @@ static int dspxfr_hci_write(struct hda_codec *codec,
         return 0;
 }
 
+/**
+ * Write a block of data into DSP code or data RAM using pre-allocated
+ * DMA engine.
+ *
+ * @codec: the HDA codec
+ * @fls: pointer to a fast load image
+ * @reloc: Relocation address for loading single-segment overlays, or 0 for
+ *         no relocation
+ * @dma_engine: pointer to DMA engine to be used for DSP download
+ * @dma_chan: The number of DMA channels used for DSP download
+ * @port_map_mask: port mapping
+ * @ovly: TRUE if overlay format is required
+ *
+ * Returns zero or a negative error code.
+ */
 static int dspxfr_one_seg(struct hda_codec *codec,
                         const struct dsp_image_seg *fls,
                         unsigned int reloc,
@@ -1836,6 +1953,18 @@ static int dspxfr_one_seg(struct hda_codec *codec,
         return status;
 }
 
+/**
+ * Write the entire DSP image of a DSP code/data overlay to DSP memories
+ *
+ * @codec: the HDA codec
+ * @fls_data: pointer to a fast load image
+ * @reloc: Relocation address for loading single-segment overlays, or 0 for
+ *         no relocation
+ * @format: format of the stream used for DSP download
+ * @ovly: TRUE if overlay format is required
+ *
+ * Returns zero or a negative error code.
+ */
 static int dspxfr_image(struct hda_codec *codec,
                         const struct dsp_image_seg *fls_data,
                         unsigned int reloc, struct hda_stream_format *format,
@@ -1970,6 +2099,23 @@ static void dspload_post_setup(struct hda_codec *codec)
         chipio_write(codec, XRAM_XRAM_INST_OFFSET(0x29), 0x00000002);
 }
 
+/**
+ * Download DSP from a DSP Image Fast Load structure. This structure is a
+ * linear, non-constant sized element array of structures, each of which
+ * contain the count of the data to be loaded, the data itself, and the
+ * corresponding starting chip address of the starting data location.
+ *
+ * @codec: the HDA codec
+ * @fls: pointer to a fast load image
+ * @ovly: TRUE if overlay format is required
+ * @reloc: Relocation address for loading single-segment overlays, or 0 for
+ *         no relocation
+ * @autostart: TRUE if DSP starts after loading; ignored if ovly is TRUE
+ * @router_chans: number of audio router channels to be allocated (0 means use
+ *                internal defaults; max is 32)
+ *
+ * Returns zero or a negative error code.
+ */
 static int dspload_image(struct hda_codec *codec,
                         const struct dsp_image_seg *fls,
                         bool ovly,