[alsa-devel] [PATCH 3/4] ASoC: fsi: modify variable name to easy to understand
Liam Girdwood
lrg at slimlogic.co.uk
Thu Sep 16 15:25:26 CEST 2010
On Thu, 2010-09-16 at 13:34 +0900, Kuninori Morimoto wrote:
> Current FSI driver is using data
> length, width, number, offset for variables.
> But it was a very confusing name.
>
> This patch rename them to easy to understand,
> and add new functions for it.
>
> Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx at renesas.com>
> ---
> sound/soc/sh/fsi.c | 179 +++++++++++++++++++++++++++++-----------------------
> 1 files changed, 99 insertions(+), 80 deletions(-)
>
> diff --git a/sound/soc/sh/fsi.c b/sound/soc/sh/fsi.c
> index 156c73b..06f1e1b 100644
> --- a/sound/soc/sh/fsi.c
> +++ b/sound/soc/sh/fsi.c
> @@ -101,6 +101,15 @@
>
> #define FSI_FMTS (SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S16_LE)
>
> +/*
> + * FSI driver use below type name for variable
> + *
> + * xxx_len : data length
> + * xxx_width : data width
> + * xxx_ofs : data offset
Best to keep this as xxx_offset
> + * xxx_num : number of data
> + */
> +
> /************************************************************************
>
>
> @@ -113,13 +122,13 @@ struct fsi_priv {
> struct snd_pcm_substream *substream;
> struct fsi_master *master;
>
> - int fifo_max;
> - int chan;
> + int fifo_max_num;
> + int chan_num;
>
> - int byte_offset;
> - int period_len;
> - int buffer_len;
> - int periods;
> + int buff_ofs;
> + int buff_len;
> + int period_width;
Do you mean the _size_ of the period here in bytes or frames or
something else ?
Fwiw, it's often better to qualify the variable with it's unit of
measurement. e.g. period_bytes or period_frames
> + int period_num;
>
> u32 mst_ctrl;
> };
> @@ -329,32 +338,43 @@ static void fsi_stream_push(struct fsi_priv *fsi,
> u32 period_len)
> {
> fsi->substream = substream;
> - fsi->buffer_len = buffer_len;
> - fsi->period_len = period_len;
> - fsi->byte_offset = 0;
> - fsi->periods = 0;
> + fsi->buff_len = buffer_len;
> + fsi->buff_ofs = 0;
> + fsi->period_width = period_len;
> + fsi->period_num = 0;
> }
>
> static void fsi_stream_pop(struct fsi_priv *fsi)
> {
> fsi->substream = NULL;
> - fsi->buffer_len = 0;
> - fsi->period_len = 0;
> - fsi->byte_offset = 0;
> - fsi->periods = 0;
> + fsi->buff_len = 0;
> + fsi->buff_ofs = 0;
> + fsi->period_width = 0;
> + fsi->period_num = 0;
> }
>
> -static int fsi_get_fifo_residue(struct fsi_priv *fsi, int is_play)
> +static int fsi_get_fifo_data_num(struct fsi_priv *fsi, int is_play)
> {
> u32 status;
> u32 reg = is_play ? DOFF_ST : DIFF_ST;
> - int residue;
> + int data_num;
>
> status = fsi_reg_read(fsi, reg);
> - residue = 0x1ff & (status >> 8);
> - residue *= fsi->chan;
> + data_num = 0x1ff & (status >> 8);
> + data_num *= fsi->chan_num;
> +
> + return data_num;
> +}
>
> - return residue;
> +static int fsi_len2num(int len, int width)
> +{
> + return len / width;
> +}
> +
> +#define fsi_num2ofs(a, b) fsi_num2len(a, b)
> +static int fsi_num2len(int num, int width)
> +{
> + return num * width;
> }
>
> /************************************************************************
> @@ -366,50 +386,50 @@ static int fsi_get_fifo_residue(struct fsi_priv *fsi, int is_play)
> ************************************************************************/
> static u8 *fsi_dma_get_area(struct fsi_priv *fsi)
> {
> - return fsi->substream->runtime->dma_area + fsi->byte_offset;
> + return fsi->substream->runtime->dma_area + fsi->buff_ofs;
> }
>
> -static void fsi_dma_soft_push16(struct fsi_priv *fsi, int size)
> +static void fsi_dma_soft_push16(struct fsi_priv *fsi, int num)
> {
> u16 *start;
> int i;
>
> start = (u16 *)fsi_dma_get_area(fsi);
>
> - for (i = 0; i < size; i++)
> + for (i = 0; i < num; i++)
> fsi_reg_write(fsi, DODT, ((u32)*(start + i) << 8));
> }
>
> -static void fsi_dma_soft_pop16(struct fsi_priv *fsi, int size)
> +static void fsi_dma_soft_pop16(struct fsi_priv *fsi, int num)
> {
> u16 *start;
> int i;
>
> start = (u16 *)fsi_dma_get_area(fsi);
>
> - for (i = 0; i < size; i++)
> + for (i = 0; i < num; i++)
> *(start + i) = (u16)(fsi_reg_read(fsi, DIDT) >> 8);
> }
>
> -static void fsi_dma_soft_push32(struct fsi_priv *fsi, int size)
> +static void fsi_dma_soft_push32(struct fsi_priv *fsi, int num)
> {
> u32 *start;
> int i;
>
> start = (u32 *)fsi_dma_get_area(fsi);
>
> - for (i = 0; i < size; i++)
> + for (i = 0; i < num; i++)
> fsi_reg_write(fsi, DODT, *(start + i));
> }
>
> -static void fsi_dma_soft_pop32(struct fsi_priv *fsi, int size)
> +static void fsi_dma_soft_pop32(struct fsi_priv *fsi, int num)
> {
> u32 *start;
> int i;
>
> start = (u32 *)fsi_dma_get_area(fsi);
>
> - for (i = 0; i < size; i++)
> + for (i = 0; i < num; i++)
> *(start + i) = fsi_reg_read(fsi, DIDT);
> }
>
> @@ -512,8 +532,8 @@ static void fsi_fifo_init(struct fsi_priv *fsi,
> shift = fsi_master_read(master, FIFO_SZ);
> shift >>= fsi_is_port_a(fsi) ? AO_SZ_SHIFT : BO_SZ_SHIFT;
> shift &= OUT_SZ_MASK;
> - fsi->fifo_max = 256 << shift;
> - dev_dbg(dai->dev, "fifo = %d words\n", fsi->fifo_max);
> + fsi->fifo_max_num = 256 << shift;
> + dev_dbg(dai->dev, "fifo = %d words\n", fsi->fifo_max_num);
>
> /*
> * The maximum number of sample data varies depending
> @@ -534,9 +554,10 @@ static void fsi_fifo_init(struct fsi_priv *fsi,
> * 7 channels: 32 ( 32 x 7 = 224)
> * 8 channels: 32 ( 32 x 8 = 256)
> */
> - for (i = 1; i < fsi->chan; i <<= 1)
> - fsi->fifo_max >>= 1;
> - dev_dbg(dai->dev, "%d channel %d store\n", fsi->chan, fsi->fifo_max);
> + for (i = 1; i < fsi->chan_num; i <<= 1)
> + fsi->fifo_max_num >>= 1;
> + dev_dbg(dai->dev, "%d channel %d store\n",
> + fsi->chan_num, fsi->fifo_max_num);
>
> ctrl = is_play ? DOFF_CTL : DIFF_CTL;
>
> @@ -565,9 +586,9 @@ static int fsi_data_push(struct fsi_priv *fsi, int startup)
> struct snd_pcm_runtime *runtime;
> struct snd_pcm_substream *substream = NULL;
> u32 status;
> - int send;
> - int fifo_free;
> - int width;
> + int push_num;
> + int push_num_max;
> + int ch_width;
> int over_period;
>
> if (!fsi ||
> @@ -582,41 +603,40 @@ static int fsi_data_push(struct fsi_priv *fsi, int startup)
> /* FSI FIFO has limit.
> * So, this driver can not send periods data at a time
> */
> - if (fsi->byte_offset >=
> - fsi->period_len * (fsi->periods + 1)) {
> + if (fsi->buff_ofs >=
> + fsi_num2ofs(fsi->period_num + 1, fsi->period_width)) {
>
> over_period = 1;
> - fsi->periods = (fsi->periods + 1) % runtime->periods;
> + fsi->period_num = (fsi->period_num + 1) % runtime->periods;
>
> - if (0 == fsi->periods)
> - fsi->byte_offset = 0;
> + if (0 == fsi->period_num)
> + fsi->buff_ofs = 0;
> }
>
> /* get 1 channel data width */
> - width = frames_to_bytes(runtime, 1) / fsi->chan;
> + ch_width = frames_to_bytes(runtime, 1) / fsi->chan_num;
>
> - /* get send size for alsa */
> - send = (fsi->buffer_len - fsi->byte_offset) / width;
> + /* number of push data */
> + push_num = fsi_len2num(fsi->buff_len - fsi->buff_ofs, ch_width);
>
> - /* get FIFO free size */
> - fifo_free = (fsi->fifo_max * fsi->chan) - fsi_get_fifo_residue(fsi, 1);
> + /* max number of push data */
> + push_num_max = (fsi->fifo_max_num * fsi->chan_num) -
> + fsi_get_fifo_data_num(fsi, 1);
>
> - /* size check */
> - if (fifo_free < send)
> - send = fifo_free;
> + push_num = min(push_num, push_num_max);
>
> - switch (width) {
> + switch (ch_width) {
> case 2:
> - fsi_dma_soft_push16(fsi, send);
> + fsi_dma_soft_push16(fsi, push_num);
> break;
> case 4:
> - fsi_dma_soft_push32(fsi, send);
> + fsi_dma_soft_push32(fsi, push_num);
> break;
> default:
> return -EINVAL;
> }
>
> - fsi->byte_offset += send * width;
> + fsi->buff_ofs += fsi_num2ofs(push_num, ch_width);
>
> status = fsi_reg_read(fsi, DOFF_ST);
> if (!startup) {
> @@ -642,9 +662,9 @@ static int fsi_data_pop(struct fsi_priv *fsi, int startup)
> struct snd_pcm_runtime *runtime;
> struct snd_pcm_substream *substream = NULL;
> u32 status;
> - int free;
> - int fifo_fill;
> - int width;
> + int pop_num;
> + int pop_num_max;
> + int ch_width;
> int over_period;
>
> if (!fsi ||
> @@ -659,40 +679,39 @@ static int fsi_data_pop(struct fsi_priv *fsi, int startup)
> /* FSI FIFO has limit.
> * So, this driver can not send periods data at a time
> */
> - if (fsi->byte_offset >=
> - fsi->period_len * (fsi->periods + 1)) {
> + if (fsi->buff_ofs >=
> + fsi_num2ofs(fsi->period_num + 1, fsi->period_width)) {
>
> over_period = 1;
> - fsi->periods = (fsi->periods + 1) % runtime->periods;
> + fsi->period_num = (fsi->period_num + 1) % runtime->periods;
>
> - if (0 == fsi->periods)
> - fsi->byte_offset = 0;
> + if (0 == fsi->period_num)
> + fsi->buff_ofs = 0;
> }
>
> /* get 1 channel data width */
> - width = frames_to_bytes(runtime, 1) / fsi->chan;
> + ch_width = frames_to_bytes(runtime, 1) / fsi->chan_num;
>
> /* get free space for alsa */
> - free = (fsi->buffer_len - fsi->byte_offset) / width;
> + pop_num_max = fsi_len2num(fsi->buff_len - fsi->buff_ofs, ch_width);
>
> /* get recv size */
> - fifo_fill = fsi_get_fifo_residue(fsi, 0);
> + pop_num = fsi_get_fifo_data_num(fsi, 0);
>
> - if (free < fifo_fill)
> - fifo_fill = free;
> + pop_num = min(pop_num_max, pop_num);
>
> - switch (width) {
> + switch (ch_width) {
> case 2:
> - fsi_dma_soft_pop16(fsi, fifo_fill);
> + fsi_dma_soft_pop16(fsi, pop_num);
> break;
> case 4:
> - fsi_dma_soft_pop32(fsi, fifo_fill);
> + fsi_dma_soft_pop32(fsi, pop_num);
> break;
> default:
> return -EINVAL;
> }
>
> - fsi->byte_offset += fifo_fill * width;
> + fsi->buff_ofs += fsi_num2ofs(pop_num, ch_width);
>
> status = fsi_reg_read(fsi, DIFF_ST);
> if (!startup) {
> @@ -786,29 +805,29 @@ static int fsi_dai_startup(struct snd_pcm_substream *substream,
> switch (fmt) {
> case SH_FSI_FMT_MONO:
> data = CR_MONO;
> - fsi->chan = 1;
> + fsi->chan_num = 1;
> break;
> case SH_FSI_FMT_MONO_DELAY:
> data = CR_MONO_D;
> - fsi->chan = 1;
> + fsi->chan_num = 1;
> break;
> case SH_FSI_FMT_PCM:
> data = CR_PCM;
> - fsi->chan = 2;
> + fsi->chan_num = 2;
> break;
> case SH_FSI_FMT_I2S:
> data = CR_I2S;
> - fsi->chan = 2;
> + fsi->chan_num = 2;
> break;
> case SH_FSI_FMT_TDM:
> - fsi->chan = is_play ?
> + fsi->chan_num = is_play ?
> SH_FSI_GET_CH_O(flags) : SH_FSI_GET_CH_I(flags);
> - data = CR_TDM | (fsi->chan - 1);
> + data = CR_TDM | (fsi->chan_num - 1);
> break;
> case SH_FSI_FMT_TDM_DELAY:
> - fsi->chan = is_play ?
> + fsi->chan_num = is_play ?
> SH_FSI_GET_CH_O(flags) : SH_FSI_GET_CH_I(flags);
> - data = CR_TDM_D | (fsi->chan - 1);
> + data = CR_TDM_D | (fsi->chan_num - 1);
> break;
> case SH_FSI_FMT_SPDIF:
> if (master->core->ver < 2) {
> @@ -816,7 +835,7 @@ static int fsi_dai_startup(struct snd_pcm_substream *substream,
> return -EINVAL;
> }
> data = CR_SPDIF;
> - fsi->chan = 2;
> + fsi->chan_num = 2;
> fsi_spdif_clk_ctrl(fsi, 1);
> fsi_reg_mask_set(fsi, OUT_SEL, 0x0010, 0x0010);
> break;
> @@ -1018,7 +1037,7 @@ static snd_pcm_uframes_t fsi_pointer(struct snd_pcm_substream *substream)
> struct fsi_priv *fsi = fsi_get_priv(substream);
> long location;
>
> - location = (fsi->byte_offset - 1);
> + location = (fsi->buff_ofs - 1);
> if (location < 0)
> location = 0;
>
--
Freelance Developer, SlimLogic Ltd
ASoC and Voltage Regulator Maintainer.
http://www.slimlogic.co.uk
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