[alsa-devel] [PATCH 2/9] ASoC: sh: fsi: tidyup unclear variable naming
Kuninori Morimoto
kuninori.morimoto.gx at renesas.com
Mon May 23 13:46:03 CEST 2011
Some variables on this driver were a unclear naming,
and were different unit (byte, frame, sample).
And some functions had wrong name
(ex. it returned "sample width" but name was "fsi_get_frame_width").
This patch tidy-up this issue, and the minimum unit become "sample".
Special thanks to Takashi YOSHII.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx at renesas.com>
---
sound/soc/sh/fsi.c | 182 ++++++++++++++++++++++++++++-----------------------
1 files changed, 100 insertions(+), 82 deletions(-)
diff --git a/sound/soc/sh/fsi.c b/sound/soc/sh/fsi.c
index 7025885..14fed47 100644
--- a/sound/soc/sh/fsi.c
+++ b/sound/soc/sh/fsi.c
@@ -118,10 +118,38 @@ typedef int (*set_rate_func)(struct device *dev, int is_porta, int rate, int ena
/*
* FSI driver use below type name for variable
*
- * xxx_len : data length
- * xxx_width : data width
- * xxx_offset : data offset
* xxx_num : number of data
+ * xxx_pos : position of data
+ * xxx_capa : capacity of data
+ */
+
+/*
+ * period/frame/sample image
+ *
+ * ex) PCM (2ch)
+ *
+ * period pos period pos
+ * [n] [n + 1]
+ * |<-------------------- period--------------------->|
+ * ==|============================================ ... =|==
+ * | |
+ * ||<----- frame ----->|<------ frame ----->| ... |
+ * |+--------------------+--------------------+- ... |
+ * ||[ sample ][ sample ]|[ sample ][ sample ]| ... |
+ * |+--------------------+--------------------+- ... |
+ * ==|============================================ ... =|==
+ */
+
+/*
+ * FSI FIFO image
+ *
+ * | |
+ * | |
+ * | [ sample ] |
+ * | [ sample ] |
+ * | [ sample ] |
+ * | [ sample ] |
+ * --> go to codecs
*/
/*
@@ -131,12 +159,11 @@ typedef int (*set_rate_func)(struct device *dev, int is_porta, int rate, int ena
struct fsi_stream {
struct snd_pcm_substream *substream;
- int fifo_max_num;
-
- int buff_offset;
- int buff_len;
- int period_len;
- int period_num;
+ int fifo_sample_capa; /* sample capacity of FSI FIFO */
+ int buff_sample_capa; /* sample capacity of ALSA buffer */
+ int buff_sample_pos; /* sample position of ALSA buffer */
+ int period_samples; /* sample number / 1 period */
+ int period_pos; /* current period position */
int uerr_num;
int oerr_num;
@@ -342,6 +369,16 @@ static u32 fsi_get_port_shift(struct fsi_priv *fsi, int is_play)
return shift;
}
+static int fsi_frame2sample(struct fsi_priv *fsi, int frames)
+{
+ return frames * fsi->chan_num;
+}
+
+static int fsi_sample2frame(struct fsi_priv *fsi, int samples)
+{
+ return samples / fsi->chan_num;
+}
+
static void fsi_stream_push(struct fsi_priv *fsi,
int is_play,
struct snd_pcm_substream *substream)
@@ -350,10 +387,10 @@ static void fsi_stream_push(struct fsi_priv *fsi,
struct snd_pcm_runtime *runtime = substream->runtime;
io->substream = substream;
- io->buff_len = frames_to_bytes(runtime, runtime->buffer_size);
- io->buff_offset = 0;
- io->period_len = frames_to_bytes(runtime, runtime->period_size);
- io->period_num = 0;
+ io->buff_sample_capa = fsi_frame2sample(fsi, runtime->buffer_size);
+ io->buff_sample_pos = 0;
+ io->period_samples = fsi_frame2sample(fsi, runtime->period_size);
+ io->period_pos = 0;
io->oerr_num = -1; /* ignore 1st err */
io->uerr_num = -1; /* ignore 1st err */
}
@@ -371,47 +408,26 @@ static void fsi_stream_pop(struct fsi_priv *fsi, int is_play)
dev_err(dai->dev, "under_run = %d\n", io->uerr_num);
io->substream = NULL;
- io->buff_len = 0;
- io->buff_offset = 0;
- io->period_len = 0;
- io->period_num = 0;
+ io->buff_sample_capa = 0;
+ io->buff_sample_pos = 0;
+ io->period_samples = 0;
+ io->period_pos = 0;
io->oerr_num = 0;
io->uerr_num = 0;
}
-static int fsi_get_fifo_data_num(struct fsi_priv *fsi, int is_play)
+static int fsi_get_current_fifo_samples(struct fsi_priv *fsi, int is_play)
{
u32 status;
- int data_num;
+ int frames;
status = is_play ?
fsi_reg_read(fsi, DOFF_ST) :
fsi_reg_read(fsi, DIFF_ST);
- data_num = 0x1ff & (status >> 8);
- data_num *= fsi->chan_num;
-
- return data_num;
-}
-
-static int fsi_len2num(int len, int width)
-{
- return len / width;
-}
+ frames = 0x1ff & (status >> 8);
-#define fsi_num2offset(a, b) fsi_num2len(a, b)
-static int fsi_num2len(int num, int width)
-{
- return num * width;
-}
-
-static int fsi_get_frame_width(struct fsi_priv *fsi, int is_play)
-{
- struct fsi_stream *io = fsi_get_stream(fsi, is_play);
- struct snd_pcm_substream *substream = io->substream;
- struct snd_pcm_runtime *runtime = substream->runtime;
-
- return frames_to_bytes(runtime, 1) / fsi->chan_num;
+ return fsi_frame2sample(fsi, frames);
}
static void fsi_count_fifo_err(struct fsi_priv *fsi)
@@ -443,8 +459,10 @@ static u8 *fsi_dma_get_area(struct fsi_priv *fsi, int stream)
{
int is_play = fsi_stream_is_play(stream);
struct fsi_stream *io = fsi_get_stream(fsi, is_play);
+ struct snd_pcm_runtime *runtime = io->substream->runtime;
- return io->substream->runtime->dma_area + io->buff_offset;
+ return runtime->dma_area +
+ samples_to_bytes(runtime, io->buff_sample_pos);
}
static void fsi_dma_soft_push16(struct fsi_priv *fsi, int num)
@@ -602,13 +620,14 @@ static void fsi_fifo_init(struct fsi_priv *fsi,
struct fsi_master *master = fsi_get_master(fsi);
struct fsi_stream *io = fsi_get_stream(fsi, is_play);
u32 shift, i;
+ int frame_capa;
/* get on-chip RAM capacity */
shift = fsi_master_read(master, FIFO_SZ);
shift >>= fsi_get_port_shift(fsi, is_play);
shift &= FIFO_SZ_MASK;
- io->fifo_max_num = 256 << shift;
- dev_dbg(dai->dev, "fifo = %d words\n", io->fifo_max_num);
+ frame_capa = 256 << shift;
+ dev_dbg(dai->dev, "fifo = %d words\n", frame_capa);
/*
* The maximum number of sample data varies depending
@@ -630,9 +649,11 @@ static void fsi_fifo_init(struct fsi_priv *fsi,
* 8 channels: 32 ( 32 x 8 = 256)
*/
for (i = 1; i < fsi->chan_num; i <<= 1)
- io->fifo_max_num >>= 1;
+ frame_capa >>= 1;
dev_dbg(dai->dev, "%d channel %d store\n",
- fsi->chan_num, io->fifo_max_num);
+ fsi->chan_num, frame_capa);
+
+ io->fifo_sample_capa = fsi_frame2sample(fsi, frame_capa);
/*
* set interrupt generation factor
@@ -653,10 +674,10 @@ static int fsi_fifo_data_ctrl(struct fsi_priv *fsi, int stream)
struct snd_pcm_substream *substream = NULL;
int is_play = fsi_stream_is_play(stream);
struct fsi_stream *io = fsi_get_stream(fsi, is_play);
- int data_residue_num;
- int data_num;
- int data_num_max;
- int ch_width;
+ int sample_residues;
+ int sample_width;
+ int samples;
+ int samples_max;
int over_period;
void (*fn)(struct fsi_priv *fsi, int size);
@@ -672,36 +693,35 @@ static int fsi_fifo_data_ctrl(struct fsi_priv *fsi, int stream)
/* FSI FIFO has limit.
* So, this driver can not send periods data at a time
*/
- if (io->buff_offset >=
- fsi_num2offset(io->period_num + 1, io->period_len)) {
+ if (io->buff_sample_pos >=
+ io->period_samples * (io->period_pos + 1)) {
over_period = 1;
- io->period_num = (io->period_num + 1) % runtime->periods;
+ io->period_pos = (io->period_pos + 1) % runtime->periods;
- if (0 == io->period_num)
- io->buff_offset = 0;
+ if (0 == io->period_pos)
+ io->buff_sample_pos = 0;
}
- /* get 1 channel data width */
- ch_width = fsi_get_frame_width(fsi, is_play);
+ /* get 1 sample data width */
+ sample_width = samples_to_bytes(runtime, 1);
- /* get residue data number of alsa */
- data_residue_num = fsi_len2num(io->buff_len - io->buff_offset,
- ch_width);
+ /* get number of residue samples */
+ sample_residues = io->buff_sample_capa - io->buff_sample_pos;
if (is_play) {
/*
* for play-back
*
- * data_num_max : number of FSI fifo free space
- * data_num : number of ALSA residue data
+ * samples_max : number of FSI fifo free samples space
+ * samples : number of ALSA residue samples
*/
- data_num_max = io->fifo_max_num * fsi->chan_num;
- data_num_max -= fsi_get_fifo_data_num(fsi, is_play);
+ samples_max = io->fifo_sample_capa;
+ samples_max -= fsi_get_current_fifo_samples(fsi, is_play);
- data_num = data_residue_num;
+ samples = sample_residues;
- switch (ch_width) {
+ switch (sample_width) {
case 2:
fn = fsi_dma_soft_push16;
break;
@@ -715,13 +735,13 @@ static int fsi_fifo_data_ctrl(struct fsi_priv *fsi, int stream)
/*
* for capture
*
- * data_num_max : number of ALSA free space
- * data_num : number of data in FSI fifo
+ * samples_max : number of ALSA free samples space
+ * samples : number of samples in FSI fifo
*/
- data_num_max = data_residue_num;
- data_num = fsi_get_fifo_data_num(fsi, is_play);
+ samples_max = sample_residues;
+ samples = fsi_get_current_fifo_samples(fsi, is_play);
- switch (ch_width) {
+ switch (sample_width) {
case 2:
fn = fsi_dma_soft_pop16;
break;
@@ -733,12 +753,12 @@ static int fsi_fifo_data_ctrl(struct fsi_priv *fsi, int stream)
}
}
- data_num = min(data_num, data_num_max);
+ samples = min(samples, samples_max);
- fn(fsi, data_num);
+ fn(fsi, samples);
- /* update buff_offset */
- io->buff_offset += fsi_num2offset(data_num, ch_width);
+ /* update buff_sample_pos */
+ io->buff_sample_pos += samples;
if (over_period)
snd_pcm_period_elapsed(substream);
@@ -1093,16 +1113,14 @@ static int fsi_hw_free(struct snd_pcm_substream *substream)
static snd_pcm_uframes_t fsi_pointer(struct snd_pcm_substream *substream)
{
- struct snd_pcm_runtime *runtime = substream->runtime;
struct fsi_priv *fsi = fsi_get_priv(substream);
struct fsi_stream *io = fsi_get_stream(fsi, fsi_is_play(substream));
- long location;
+ int samples_pos = io->buff_sample_pos - 1;
- location = (io->buff_offset - 1);
- if (location < 0)
- location = 0;
+ if (samples_pos < 0)
+ samples_pos = 0;
- return bytes_to_frames(runtime, location);
+ return fsi_sample2frame(fsi, samples_pos);
}
static struct snd_pcm_ops fsi_pcm_ops = {
--
1.7.1
More information about the Alsa-devel
mailing list