Re: [alsa-devel] [PATCH 1/3] ASoC: DaVinci: Added two clocking possibilities to McBSP (I2S)

On Tue, 2010-07-06 at 10:39 +0200, Raffaele Recalcati wrote:

From: Raffaele Recalcati raffaele.recalcati@bticino.it

Added two clocking options for dm365 McBSP peripheral when used
with I2S timings, that are SND_SOC_DAIFMT_CBS_CFS (the cpu generates
clock and frame sync) and SND_SOC_DAIFMT_CBS_CFM (the cpu gets clock
from external pin and generates frame sync).
A slave clock management can be important when the external codec needs
the system clock and the bit clock synchronized (tested with uda1345).
This patch has been developed against the:
    http://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-davinci.git
git tree and has been tested on bmx board (similar to dm365 evm, but using
uda1345 as external audio codec).

Signed-off-by: Raffaele Recalcati raffaele.recalcati@bticino.it Signed-off-by: Davide Bonfanti davide.bonfanti@bticino.it

All

Acked-by: Liam Girdwood lrg@slimlogic.co.uk

But lets get some feedback from the DaVinci folks on this too.

---

sound/soc/davinci/davinci-i2s.c | 110 +++++++++++++++++++++++++++++++++++--- sound/soc/davinci/davinci-i2s.h | 5 ++ 2 files changed, 106 insertions(+), 9 deletions(-)

diff --git a/sound/soc/davinci/davinci-i2s.c b/sound/soc/davinci/davinci-i2s.c index adadcd3..c8f038c 100644 --- a/sound/soc/davinci/davinci-i2s.c +++ b/sound/soc/davinci/davinci-i2s.c @@ -26,6 +26,7 @@ #include <mach/asp.h>

#include "davinci-pcm.h" +#include "davinci-i2s.h"

/* @@ -68,16 +69,21 @@ #define DAVINCI_MCBSP_RCR_RDATDLY(v) ((v) << 16) #define DAVINCI_MCBSP_RCR_RFIG (1 << 18) #define DAVINCI_MCBSP_RCR_RWDLEN2(v) ((v) << 21) +#define DAVINCI_MCBSP_RCR_RFRLEN2(v) ((v) << 24) +#define DAVINCI_MCBSP_RCR_RPHASE BIT(31)

#define DAVINCI_MCBSP_XCR_XWDLEN1(v) ((v) << 5) #define DAVINCI_MCBSP_XCR_XFRLEN1(v) ((v) << 8) #define DAVINCI_MCBSP_XCR_XDATDLY(v) ((v) << 16) #define DAVINCI_MCBSP_XCR_XFIG (1 << 18) #define DAVINCI_MCBSP_XCR_XWDLEN2(v) ((v) << 21) +#define DAVINCI_MCBSP_XCR_XFRLEN2(v) ((v) << 24) +#define DAVINCI_MCBSP_XCR_XPHASE BIT(31)

#define DAVINCI_MCBSP_SRGR_FWID(v) ((v) << 8) #define DAVINCI_MCBSP_SRGR_FPER(v) ((v) << 16) #define DAVINCI_MCBSP_SRGR_FSGM (1 << 28) +#define DAVINCI_MCBSP_SRGR_CLKSM BIT(29)

#define DAVINCI_MCBSP_PCR_CLKRP (1 << 0) #define DAVINCI_MCBSP_PCR_CLKXP (1 << 1) @@ -144,6 +150,9 @@ struct davinci_mcbsp_dev { * won't end up being swapped because of the underrun. */ unsigned enable_channel_combine:1;

• unsigned int fmt;
• int clk_div;

};

static inline void davinci_mcbsp_write_reg(struct davinci_mcbsp_dev *dev, @@ -254,10 +263,12 @@ static int davinci_i2s_set_dai_fmt(struct snd_soc_dai *cpu_dai, struct davinci_mcbsp_dev *dev = cpu_dai->private_data; unsigned int pcr; unsigned int srgr;

• /* Attention srgr is updated by hw_params! */ srgr = DAVINCI_MCBSP_SRGR_FSGM | DAVINCI_MCBSP_SRGR_FPER(DEFAULT_BITPERSAMPLE * 2 - 1) | DAVINCI_MCBSP_SRGR_FWID(DEFAULT_BITPERSAMPLE - 1);

• dev->fmt = fmt; /* set master/slave audio interface */ switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) { case SND_SOC_DAIFMT_CBS_CFS:

@@ -372,6 +383,18 @@ static int davinci_i2s_set_dai_fmt(struct snd_soc_dai *cpu_dai, return 0; }

+static int davinci_i2s_dai_set_clkdiv(struct snd_soc_dai *cpu_dai,

• 		int div_id, int div)
  

+{

• struct davinci_mcbsp_dev *dev = cpu_dai->private_data;
• if (div_id != DAVINCI_MCBSP_CLKGDV)

• return -ENODEV;
  

• dev->clk_div = div;
• return 0;

+}

static int davinci_i2s_hw_params(struct snd_pcm_substream *substream, struct snd_pcm_hw_params *params, struct snd_soc_dai *dai) @@ -380,8 +403,8 @@ static int davinci_i2s_hw_params(struct snd_pcm_substream *substream, struct davinci_pcm_dma_params *dma_params = &dev->dma_params[substream->stream]; struct snd_interval *i = NULL;

• int mcbsp_word_length;
• unsigned int rcr, xcr, srgr;

• int mcbsp_word_length, master;
• unsigned int rcr, xcr, srgr, clk_div, freq, framesize; u32 spcr; snd_pcm_format_t fmt; unsigned element_cnt = 1;

@@ -396,12 +419,47 @@ static int davinci_i2s_hw_params(struct snd_pcm_substream *substream, davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_SPCR_REG, spcr); }

• i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
• srgr = DAVINCI_MCBSP_SRGR_FSGM;
• srgr |= DAVINCI_MCBSP_SRGR_FWID(snd_interval_value(i) - 1);

• master = dev->fmt & SND_SOC_DAIFMT_MASTER_MASK;
• fmt = params_format(params);
• mcbsp_word_length = asp_word_length[fmt];

• i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_FRAME_BITS);
• srgr |= DAVINCI_MCBSP_SRGR_FPER(snd_interval_value(i) - 1);

• switch (master) {

• case SND_SOC_DAIFMT_CBS_CFS:

• freq = clk_get_rate(dev->clk);
  

• srgr = DAVINCI_MCBSP_SRGR_FSGM |
  

•        DAVINCI_MCBSP_SRGR_CLKSM;
  

• srgr |= DAVINCI_MCBSP_SRGR_FWID(mcbsp_word_length *
  

• 				8 - 1);
  

• /* symmetric waveforms */
  

• clk_div = freq / (mcbsp_word_length * 16) /
  

• 	  params->rate_num * params->rate_den;
  

• srgr |= DAVINCI_MCBSP_SRGR_FPER(mcbsp_word_length *
  

• 				16 - 1);
  

• clk_div &= 0xFF;
  

• srgr |= clk_div;
  

• break;
  

• case SND_SOC_DAIFMT_CBM_CFS:

• srgr = DAVINCI_MCBSP_SRGR_FSGM;
  

• clk_div = dev->clk_div - 1;
  

• srgr |= DAVINCI_MCBSP_SRGR_FWID(mcbsp_word_length * 8 - 1);
  

• srgr |= DAVINCI_MCBSP_SRGR_FPER(mcbsp_word_length * 16 - 1);
  

• clk_div &= 0xFF;
  

• srgr |= clk_div;
  

• break;
  

• case SND_SOC_DAIFMT_CBM_CFM:

• /* Clock and frame sync given from external sources */
  

• i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_SAMPLE_BITS);
  

• srgr = DAVINCI_MCBSP_SRGR_FSGM;
  

• srgr |= DAVINCI_MCBSP_SRGR_FWID(snd_interval_value(i) - 1);
  

• pr_debug("%s - %d  FWID set: re-read srgr = %X\n",
  

• 	__func__, __LINE__, snd_interval_value(i) - 1);
  

• i = hw_param_interval(params, SNDRV_PCM_HW_PARAM_FRAME_BITS);
  

• srgr |= DAVINCI_MCBSP_SRGR_FPER(snd_interval_value(i) - 1);
  

• break;
  

• default:

• return -EINVAL;
  

• } davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_SRGR_REG, srgr);

  rcr = DAVINCI_MCBSP_RCR_RFIG;

@@ -426,12 +484,41 @@ static int davinci_i2s_hw_params(struct snd_pcm_substream *substream, element_cnt = 1; fmt = double_fmt[fmt]; }

• switch (master) {
  

• case SND_SOC_DAIFMT_CBS_CFS:
  

• case SND_SOC_DAIFMT_CBS_CFM:
  

• 	rcr |= DAVINCI_MCBSP_RCR_RFRLEN2(0);
  

• 	xcr |= DAVINCI_MCBSP_XCR_XFRLEN2(0);
  

• 	rcr |= DAVINCI_MCBSP_RCR_RPHASE;
  

• 	xcr |= DAVINCI_MCBSP_XCR_XPHASE;
  

• 	break;
  

• case SND_SOC_DAIFMT_CBM_CFM:
  

• case SND_SOC_DAIFMT_CBM_CFS:
  

• 	rcr |= DAVINCI_MCBSP_RCR_RFRLEN2(element_cnt - 1);
  

• 	xcr |= DAVINCI_MCBSP_XCR_XFRLEN2(element_cnt - 1);
  

• 	break;
  

• default:
  

• 	return -EINVAL;
  

• }
  

  } dma_params->acnt = dma_params->data_type = data_type[fmt]; dma_params->fifo_level = 0; mcbsp_word_length = asp_word_length[fmt];

• rcr |= DAVINCI_MCBSP_RCR_RFRLEN1(element_cnt - 1);
• xcr |= DAVINCI_MCBSP_XCR_XFRLEN1(element_cnt - 1);

• switch (master) {

• case SND_SOC_DAIFMT_CBS_CFS:

• case SND_SOC_DAIFMT_CBS_CFM:

• rcr |= DAVINCI_MCBSP_RCR_RFRLEN1(0);
  

• xcr |= DAVINCI_MCBSP_XCR_XFRLEN1(0);
  

• break;
  

• case SND_SOC_DAIFMT_CBM_CFM:

• case SND_SOC_DAIFMT_CBM_CFS:

• rcr |= DAVINCI_MCBSP_RCR_RFRLEN1(element_cnt - 1);
  

• xcr |= DAVINCI_MCBSP_XCR_XFRLEN1(element_cnt - 1);
  

• break;
  

• default:

• return -EINVAL;
  

• }

  rcr |= DAVINCI_MCBSP_RCR_RWDLEN1(mcbsp_word_length) | DAVINCI_MCBSP_RCR_RWDLEN2(mcbsp_word_length);

@@ -442,6 +529,10 @@ static int davinci_i2s_hw_params(struct snd_pcm_substream *substream, davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_XCR_REG, xcr); else davinci_mcbsp_write_reg(dev, DAVINCI_MCBSP_RCR_REG, rcr);

• pr_debug("%s - %d srgr=%X\n", __func__, __LINE__, srgr);
• pr_debug("%s - %d xcr=%X\n", __func__, __LINE__, xcr);
• pr_debug("%s - %d rcr=%X\n", __func__, __LINE__, rcr); return 0;

}

@@ -500,6 +591,7 @@ static struct snd_soc_dai_ops davinci_i2s_dai_ops = { .trigger = davinci_i2s_trigger, .hw_params = davinci_i2s_hw_params, .set_fmt = davinci_i2s_set_dai_fmt,

• .set_clkdiv = davinci_i2s_dai_set_clkdiv,

};

diff --git a/sound/soc/davinci/davinci-i2s.h b/sound/soc/davinci/davinci-i2s.h index 241648c..0b1e77b 100644 --- a/sound/soc/davinci/davinci-i2s.h +++ b/sound/soc/davinci/davinci-i2s.h @@ -12,6 +12,11 @@ #ifndef _DAVINCI_I2S_H #define _DAVINCI_I2S_H

+/* McBSP dividers */ +enum davinci_mcbsp_div {

• DAVINCI_MCBSP_CLKGDV, /* Sample rate generator divider */

+};

extern struct snd_soc_dai davinci_i2s_dai;

#endif