From: Graeme Gregory gg@slimlogic.co.uk
This patch increases the number of supported audio channels from 4 to 16 and was sponsored by Shotspotter inc.
Signed-off-by: Graeme Gregory gg@slimlogic.co.uk Signed-off-by: Liam Girdwood lrg@slimlogic.co.uk --- sound/soc/omap/omap-mcbsp.c | 71 +++++++++++++++++++++++++++++------------- 1 files changed, 49 insertions(+), 22 deletions(-)
diff --git a/sound/soc/omap/omap-mcbsp.c b/sound/soc/omap/omap-mcbsp.c index 3341f49..290ef2f 100644 --- a/sound/soc/omap/omap-mcbsp.c +++ b/sound/soc/omap/omap-mcbsp.c @@ -49,6 +49,8 @@ struct omap_mcbsp_data { */ int active; int configured; + unsigned int in_freq; + int clk_div; };
#define to_mcbsp(priv) container_of((priv), struct omap_mcbsp_data, bus_id) @@ -257,7 +259,7 @@ static int omap_mcbsp_dai_hw_params(struct snd_pcm_substream *substream, int dma, bus_id = mcbsp_data->bus_id, id = cpu_dai->id; int wlen, channels, wpf, sync_mode = OMAP_DMA_SYNC_ELEMENT; unsigned long port; - unsigned int format; + unsigned int format, frame_size, div;
if (cpu_class_is_omap1()) { dma = omap1_dma_reqs[bus_id][substream->stream]; @@ -294,27 +296,23 @@ static int omap_mcbsp_dai_hw_params(struct snd_pcm_substream *substream,
format = mcbsp_data->fmt & SND_SOC_DAIFMT_FORMAT_MASK; wpf = channels = params_channels(params); - switch (channels) { - case 2: - if (format == SND_SOC_DAIFMT_I2S) { - /* Use dual-phase frames */ - regs->rcr2 |= RPHASE; - regs->xcr2 |= XPHASE; - /* Set 1 word per (McBSP) frame for phase1 and phase2 */ - wpf--; - regs->rcr2 |= RFRLEN2(wpf - 1); - regs->xcr2 |= XFRLEN2(wpf - 1); - } - case 1: - case 4: + if (channels == 2 && format == SND_SOC_DAIFMT_I2S) { + /* Use dual-phase frames */ + regs->rcr2 |= RPHASE; + regs->xcr2 |= XPHASE; + /* Set 1 word per (McBSP) frame for phase1 and phase2 */ + wpf--; + regs->rcr2 |= RFRLEN2(wpf - 1); + regs->xcr2 |= XFRLEN2(wpf - 1); /* Set word per (McBSP) frame for phase1 */ regs->rcr1 |= RFRLEN1(wpf - 1); regs->xcr1 |= XFRLEN1(wpf - 1); - break; - default: + } else if (channels > 0 && channels < 17) { + regs->rcr1 |= RFRLEN1(wpf - 1); + regs->xcr1 |= XFRLEN1(wpf - 1); + } else /* Unsupported number of channels */ return -EINVAL; - }
switch (params_format(params)) { case SNDRV_PCM_FORMAT_S16_LE: @@ -330,6 +328,34 @@ static int omap_mcbsp_dai_hw_params(struct snd_pcm_substream *substream, return -EINVAL; }
+ /* Default div to 1 if it wasn't set by machine driver, otherwise + * use set div as the maximum clock value + */ + div = mcbsp_data->clk_div ? mcbsp_data->clk_div : 1; + + /* calc best frame size for rate and clock divider */ + do { + frame_size = (mcbsp_data->in_freq / div) / params_rate(params); + pr_debug("freq %d, rate %d, frame size %d, div %d\n", + mcbsp_data->in_freq, params_rate(params), frame_size, div); + + if (frame_size > 256) + div++; + } while (frame_size > 256); + + /* Check we can fit the requested number of channels into our + * calculated frame size + */ + if ((channels * wlen) > frame_size) { + printk(KERN_ERR + "OMAP-MCBSP: cannot fit channels in frame size\n"); + return -EINVAL; + } + + /* Set the actual clkdiv to use for this samplerate */ + regs->srgr1 &= ~CLKGDV(0xFF); + regs->srgr1 |= CLKGDV(div - 1); + /* Set FS period and length in terms of bit clock periods */ switch (format) { case SND_SOC_DAIFMT_I2S: @@ -338,7 +364,7 @@ static int omap_mcbsp_dai_hw_params(struct snd_pcm_substream *substream, break; case SND_SOC_DAIFMT_DSP_A: case SND_SOC_DAIFMT_DSP_B: - regs->srgr2 |= FPER(wlen * channels - 1); + regs->srgr2 |= FPER(frame_size - 1); regs->srgr1 |= FWID(0); break; } @@ -449,12 +475,11 @@ static int omap_mcbsp_dai_set_clkdiv(struct snd_soc_dai *cpu_dai, int div_id, int div) { struct omap_mcbsp_data *mcbsp_data = to_mcbsp(cpu_dai->private_data); - struct omap_mcbsp_reg_cfg *regs = &mcbsp_data->regs;
if (div_id != OMAP_MCBSP_CLKGDV) return -ENODEV;
- regs->srgr1 |= CLKGDV(div - 1); + mcbsp_data->clk_div = div;
return 0; } @@ -554,6 +579,8 @@ static int omap_mcbsp_dai_set_dai_sysclk(struct snd_soc_dai *cpu_dai, struct omap_mcbsp_reg_cfg *regs = &mcbsp_data->regs; int err = 0;
+ mcbsp_data->in_freq = freq; + switch (clk_id) { case OMAP_MCBSP_SYSCLK_CLK: regs->srgr2 |= CLKSM; @@ -598,13 +625,13 @@ static struct snd_soc_dai_ops omap_mcbsp_dai_ops = { .id = (link_id), \ .playback = { \ .channels_min = 1, \ - .channels_max = 4, \ + .channels_max = 16, \ .rates = OMAP_MCBSP_RATES, \ .formats = SNDRV_PCM_FMTBIT_S16_LE, \ }, \ .capture = { \ .channels_min = 1, \ - .channels_max = 4, \ + .channels_max = 16, \ .rates = OMAP_MCBSP_RATES, \ .formats = SNDRV_PCM_FMTBIT_S16_LE, \ }, \