[alsa-devel] [PATCH 4/5] ASoC: dwc: Add devicetree support for Designware I2S
Andrew Jackson
Andrew.Jackson at arm.com
Thu Dec 4 11:00:04 CET 2014
On 12/04/14 07:43, rajeev kumar wrote:
> Sorry for the last blank mail.
>
> On Wed, Dec 3, 2014 at 10:09 PM, Andrew Jackson <Andrew.Jackson at arm.com> wrote:
>> Convert to driver to use either platform_data or device-tree for configuration
>> of the device. When using device-tree, the I2S block's configuration is read
>> from the relevant registers: this reduces the amount of information required in
>> the device tree.
>>
>> Signed-off-by: Andrew Jackson <Andrew.Jackson at arm.com>
>> ---
>> .../devicetree/bindings/sound/designware-i2s.txt | 32 +++
>> sound/soc/dwc/Kconfig | 1 +
>> sound/soc/dwc/designware_i2s.c | 238 ++++++++++++++++----
>> 3 files changed, 222 insertions(+), 49 deletions(-)
>> create mode 100644 Documentation/devicetree/bindings/sound/designware-i2s.txt
>>
>> diff --git a/Documentation/devicetree/bindings/sound/designware-i2s.txt b/Documentation/devicetree/bindings/sound/designware-i2s.txt
>> new file mode 100644
>> index 0000000..cdee591
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/sound/designware-i2s.txt
>> @@ -0,0 +1,32 @@
>> +DesignWare I2S controller
>> +
>> +Required properties:
>> + - compatible : Must be "snps,designware-i2s"
>> + - reg : Must contain I2S core's registers location and length
>> + - clocks : Pairs of phandle and specifier referencing the controller's clocks.
>> + The controller expects two clocks, the clock used for the APB interface and
>> + the clock used as the sampling rate reference clock sample.
>> + - clock-names : "apb_plck" for the clock to the APB interface, "i2sclk" for the sample
>> + rate reference clock.
>> + - dmas: Pairs of phandle and specifier for the DMA channels that are used by
>> + the core. The core expects one or two dma channels, one for transmit and one for
>> + receive.
>> + - dma-names : "tx" for the transmit channel, "rx" for the receive channel.
>> +
>> +For more details on the 'dma', 'dma-names', 'clock' and 'clock-names' properties
>> +please check:
>> + * resource-names.txt
>> + * clock/clock-bindings.txt
>> + * dma/dma.txt
>> +
>> +Example:
>> +
>> + soc_i2s: i2s at 7ff90000 {
>> + compatible = "snps,designware-i2s";
>> + reg = <0x0 0x7ff90000 0x0 0x1000>;
>> + clocks = <&scpi_i2sclk 0>, <&soc_refclk100mhz>;
>> + clock-names = "i2sclk", "apb_pclk";
>> + #sound-dai-cells = <0>;
>> + dmas = <&dma0 5>;
>> + dma-names = "tx";
>> + };
>> diff --git a/sound/soc/dwc/Kconfig b/sound/soc/dwc/Kconfig
>> index e334900..d50e085 100644
>> --- a/sound/soc/dwc/Kconfig
>> +++ b/sound/soc/dwc/Kconfig
>> @@ -1,6 +1,7 @@
>> config SND_DESIGNWARE_I2S
>> tristate "Synopsys I2S Device Driver"
>> depends on CLKDEV_LOOKUP
>> + select SND_SOC_GENERIC_DMAENGINE_PCM
>> help
>> Say Y or M if you want to add support for I2S driver for
>> Synopsys desigwnware I2S device. The device supports upto
>> diff --git a/sound/soc/dwc/designware_i2s.c b/sound/soc/dwc/designware_i2s.c
>> index c497ada..083779d 100644
>> --- a/sound/soc/dwc/designware_i2s.c
>> +++ b/sound/soc/dwc/designware_i2s.c
>> @@ -22,6 +22,7 @@
>> #include <sound/pcm.h>
>> #include <sound/pcm_params.h>
>> #include <sound/soc.h>
>> +#include <sound/dmaengine_pcm.h>
>>
>> /* common register for all channel */
>> #define IER 0x000
>> @@ -54,19 +55,46 @@
>> #define I2S_COMP_VERSION 0x01F8
>> #define I2S_COMP_TYPE 0x01FC
>>
>> +/*
>> + * Component parameter register fields - define the I2S block's
>> + * configuration.
>> + */
>> +#define COMP1_TX_WORDSIZE_3(r) (((r) & GENMASK(27, 25)) >> 25)
>> +#define COMP1_TX_WORDSIZE_2(r) (((r) & GENMASK(24, 22)) >> 22)
>> +#define COMP1_TX_WORDSIZE_1(r) (((r) & GENMASK(21, 19)) >> 19)
>> +#define COMP1_TX_WORDSIZE_0(r) (((r) & GENMASK(18, 16)) >> 16)
>> +#define COMP1_TX_CHANNELS(r) (((r) & GENMASK(10, 9)) >> 9)
>> +#define COMP1_RX_CHANNELS(r) (((r) & GENMASK(8, 7)) >> 7)
>> +#define COMP1_RX_ENABLED(r) (((r) & BIT(6)) >> 6)
>> +#define COMP1_TX_ENABLED(r) (((r) & BIT(5)) >> 5)
>> +#define COMP1_MODE_EN(r) (((r) & BIT(4)) >> 4)
>> +#define COMP1_FIFO_DEPTH_GLOBAL(r) (((r) & GENMASK(3, 2)) >> 2)
>> +#define COMP1_APB_DATA_WIDTH(r) (((r) & GENMASK(1, 0)) >> 0)
>> +
>> +#define COMP2_RX_WORDSIZE_3(r) (((r) & GENMASK(12, 10)) >> 10)
>> +#define COMP2_RX_WORDSIZE_2(r) (((r) & GENMASK(9, 7)) >> 7)
>> +#define COMP2_RX_WORDSIZE_1(r) (((r) & GENMASK(5, 3)) >> 3)
>> +#define COMP2_RX_WORDSIZE_0(r) (((r) & GENMASK(2, 0)) >> 0)
>> +
>> #define MAX_CHANNEL_NUM 8
>> #define MIN_CHANNEL_NUM 2
>>
>> +union snd_dma_data {
>> + struct i2s_dma_data pd;
>> + struct snd_dmaengine_dai_dma_data dt;
>> +};
>> +
>> struct dw_i2s_dev {
>> void __iomem *i2s_base;
>> struct clk *clk;
>> int active;
>> unsigned int capability;
>> struct device *dev;
>> + bool using_pd;
>>
>> /* data related to DMA transfers b/w i2s and DMAC */
>> - struct i2s_dma_data play_dma_data;
>> - struct i2s_dma_data capture_dma_data;
>> + union snd_dma_data play_dma_data;
>> + union snd_dma_data capture_dma_data;
>> struct i2s_clk_config_data config;
>> int (*i2s_clk_cfg)(struct i2s_clk_config_data *config);
>> };
>> @@ -153,7 +181,7 @@ static int dw_i2s_startup(struct snd_pcm_substream *substream,
>> struct snd_soc_dai *cpu_dai)
>> {
>> struct dw_i2s_dev *dev = snd_soc_dai_get_drvdata(cpu_dai);
>> - struct i2s_dma_data *dma_data = NULL;
>> + union snd_dma_data *dma_data = NULL;
>>
>> if (!(dev->capability & DWC_I2S_RECORD) &&
>> (substream->stream == SNDRV_PCM_STREAM_CAPTURE))
>> @@ -227,8 +255,7 @@ static int dw_i2s_hw_params(struct snd_pcm_substream *substream,
>>
>> i2s_disable_channels(dev, substream->stream);
>>
>> - /* Iterate over set of channels - independently controlled.
>> - */
>> + /* Iterate over set of channels - independently controlled. */
>
> I dont think so this iteration is required as there are independent
> channels available.
>
See other email.
> I don't have the h/w to test this patch. Can anyone test this ?
>
>> do {
>> if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
>> i2s_write_reg(dev->i2s_base, TCR(ch_reg),
>> @@ -251,13 +278,18 @@ static int dw_i2s_hw_params(struct snd_pcm_substream *substream,
>>
>> config->sample_rate = params_rate(params);
>>
>> - if (!dev->i2s_clk_cfg)
>> - return -EINVAL;
>> + if (dev->using_pd) {
>> + ret = dev->i2s_clk_cfg(config);
>> + if (ret < 0) {
>> + dev_err(dev->dev, "runtime audio clk config fail\n");
>> + return ret;
>> + }
>> + } else {
>> + u32 bitclk;
>>
>> - ret = dev->i2s_clk_cfg(config);
>> - if (ret < 0) {
>> - dev_err(dev->dev, "runtime audio clk config fail\n");
>> - return ret;
>> + /* TODO: Validate sample rate against permissible set */
>> + bitclk = config->sample_rate * config->data_width * 2;
>> + clk_set_rate(dev->clk, bitclk);
>> }
>>
>> return 0;
>> @@ -331,6 +363,31 @@ static int dw_i2s_resume(struct snd_soc_dai *dai)
>> #define dw_i2s_resume NULL
>> #endif
>>
>> +/* Maximum resolution of a channel - not uniformly spaced */
>> +static const u32 fifo_width[] = {
>> + 12, 16, 20, 24, 32, 0, 0, 0
>> +};
>> +
>> +/* Width of (DMA) bus */
>> +static const u32 bus_widths[] = {
>> + DMA_SLAVE_BUSWIDTH_1_BYTE,
>> + DMA_SLAVE_BUSWIDTH_2_BYTES,
>> + DMA_SLAVE_BUSWIDTH_4_BYTES,
>> + DMA_SLAVE_BUSWIDTH_UNDEFINED
>> +};
>> +
>> +/* PCM format to support channel resolution */
>> +static const u32 formats[] = {
>> + SNDRV_PCM_FMTBIT_S16_LE,
>> + SNDRV_PCM_FMTBIT_S16_LE,
>> + SNDRV_PCM_FMTBIT_S24_LE,
>> + SNDRV_PCM_FMTBIT_S24_LE,
>> + SNDRV_PCM_FMTBIT_S32_LE,
>> + 0,
>> + 0,
>> + 0
>> +};
>> +
>> static int dw_i2s_probe(struct platform_device *pdev)
>> {
>> const struct i2s_platform_data *pdata = pdev->dev.platform_data;
>> @@ -340,11 +397,6 @@ static int dw_i2s_probe(struct platform_device *pdev)
>> unsigned int cap;
>> struct snd_soc_dai_driver *dw_i2s_dai;
>>
>> - if (!pdata) {
>> - dev_err(&pdev->dev, "Invalid platform data\n");
>> - return -EINVAL;
>> - }
>> -
>
> This check is required..
It is handled below: the absence of platform data (now) implies a device tree implementation.
>
>> dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
>> if (!dev) {
>> dev_warn(&pdev->dev, "kzalloc fail\n");
>> @@ -373,47 +425,114 @@ static int dw_i2s_probe(struct platform_device *pdev)
>> return PTR_ERR(dev->i2s_base);
>> }
>>
>> - cap = pdata->cap;
>> - dev->capability = cap;
>> - dev->i2s_clk_cfg = pdata->i2s_clk_cfg;
>> + if (pdata) {
>> + dev->using_pd = true;
>> + cap = pdata->cap;
>> + dev->capability = cap;
>
> We should take take capability from DT, as
>
> if (of_get_property(np, "play", NULL))
> cap |= DWC_I2S_PLAY;
> if (of_get_property(np, "record", NULL))
> cap |= DWC_I2S_RECORD;
>
>> + dev->i2s_clk_cfg = pdata->i2s_clk_cfg;
>> + if (!dev->i2s_clk_cfg) {
>> + dev_err(&pdev->dev, "no clock device\n");
>> + return -ENODEV;
>> + }
>>
>> - /* Set DMA slaves info */
>> + /* Set DMA slaves info */
>> +
>> + dev->play_dma_data.pd.data = pdata->play_dma_data;
>
> As pdata null check is removed it may create issue here !
No, because we're in the 'if (pdata)' section of code.
>
>> + dev->capture_dma_data.pd.data = pdata->capture_dma_data;
>> + dev->play_dma_data.pd.addr = res->start + I2S_TXDMA;
>> + dev->capture_dma_data.pd.addr = res->start + I2S_RXDMA;
>> + dev->play_dma_data.pd.max_burst = 16;
>> + dev->capture_dma_data.pd.max_burst = 16;
>> + dev->play_dma_data.pd.addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
>> + dev->capture_dma_data.pd.addr_width =
>> + DMA_SLAVE_BUSWIDTH_2_BYTES;
>> + dev->play_dma_data.pd.filter = pdata->filter;
>> + dev->capture_dma_data.pd.filter = pdata->filter;
>> +
>> + dev->clk = clk_get(&pdev->dev, NULL);
>> + if (IS_ERR(dev->clk))
>> + return PTR_ERR(dev->clk);
>> +
>> + if (cap & DWC_I2S_PLAY) {
>> + dev_dbg(&pdev->dev, " designware: play supported\n");
>> + dw_i2s_dai->playback.channels_min = MIN_CHANNEL_NUM;
>> + dw_i2s_dai->playback.channels_max = pdata->channel;
>> + dw_i2s_dai->playback.formats = pdata->snd_fmts;
>> + dw_i2s_dai->playback.rates = pdata->snd_rates;
>> + }
>>
>> - dev->play_dma_data.data = pdata->play_dma_data;
>> - dev->capture_dma_data.data = pdata->capture_dma_data;
>> - dev->play_dma_data.addr = res->start + I2S_TXDMA;
>> - dev->capture_dma_data.addr = res->start + I2S_RXDMA;
>> - dev->play_dma_data.max_burst = 16;
>> - dev->capture_dma_data.max_burst = 16;
>> - dev->play_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
>> - dev->capture_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
>> - dev->play_dma_data.filter = pdata->filter;
>> - dev->capture_dma_data.filter = pdata->filter;
>> + if (cap & DWC_I2S_RECORD) {
>> + dev_dbg(&pdev->dev, "designware: record supported\n");
>> + dw_i2s_dai->capture.channels_min = MIN_CHANNEL_NUM;
>> + dw_i2s_dai->capture.channels_max = pdata->channel;
>> + dw_i2s_dai->capture.formats = pdata->snd_fmts;
>> + dw_i2s_dai->capture.rates = pdata->snd_rates;
>> + }
>> + } else {
>> + /*
>> + * Read component parameter registers to extract
>> + * the I2S block's configuration.
>> + */
>> + u32 comp1 = i2s_read_reg(dev->i2s_base, I2S_COMP_PARAM_1);
>> + u32 comp2 = i2s_read_reg(dev->i2s_base, I2S_COMP_PARAM_2);
>> + u32 bus_width = bus_widths[COMP1_APB_DATA_WIDTH(comp1)];
>> + u32 fifo_depth = 1 << (1 + COMP1_FIFO_DEPTH_GLOBAL(comp1));
>> + u32 max_size;
>> +
>> + dev->using_pd = false;
>> +
>> + dev->clk = devm_clk_get(&pdev->dev, "i2sclk");
>> + if (IS_ERR(dev->clk))
>> + return PTR_ERR(dev->clk);
>> +
>> + /*
>> + * Code presumes all channels are configured with the same
>> + * word size.
>> + */
>
> But why all channels ? You should configure only those channel which
> are required. The number of channel you can pass from either pdata or
> DT.
> This is also not required as before play start you are going to enable
> only those channel which are required and disable others.
I will change the comment to say "configured in the IP" i.e. at design time. This is the physical configuration of the IP block.
Andrew
>
> Best Regards
> Rajeev
>
>
>> + if (COMP1_TX_ENABLED(comp1)) {
>> + dev_dbg(&pdev->dev, "playback capable\n");
>> +
>> + dev->capability |= DWC_I2S_PLAY;
>> + max_size = COMP1_TX_WORDSIZE_0(comp1);
>> + dev->play_dma_data.dt.addr = res->start + I2S_TXDMA;
>> + dev->play_dma_data.dt.addr_width = bus_width;
>> + dev->play_dma_data.dt.chan_name = "TX";
>> + dev->play_dma_data.dt.fifo_size = fifo_depth *
>> + (fifo_width[max_size]) >> 8;
>> + dev->play_dma_data.dt.maxburst = 16;
>> + dw_i2s_dai->playback.channels_min = MIN_CHANNEL_NUM;
>> + dw_i2s_dai->playback.channels_max =
>> + 1 << (COMP1_TX_CHANNELS(comp1) + 1);
>> + dw_i2s_dai->playback.formats = formats[max_size];
>> + dw_i2s_dai->playback.rates = SNDRV_PCM_RATE_8000_192000;
>> + }
>> + if (COMP1_RX_ENABLED(comp1)) {
>> + dev_dbg(&pdev->dev, "record capable\n");
>> +
>> + dev->capability |= DWC_I2S_RECORD;
>> + max_size = COMP2_RX_WORDSIZE_0(comp2);
>> + dev->capture_dma_data.dt.addr = res->start + I2S_RXDMA;
>> + dev->capture_dma_data.dt.addr_width = bus_width;
>> + dev->capture_dma_data.dt.chan_name = "RX";
>> + dev->capture_dma_data.dt.fifo_size = fifo_depth *
>> + (fifo_width[max_size] >> 8);
>> + dev->capture_dma_data.dt.maxburst = 16;
>> + dw_i2s_dai->capture.channels_min = MIN_CHANNEL_NUM;
>> + dw_i2s_dai->capture.channels_max =
>> + 1 << (COMP1_RX_CHANNELS(comp1) + 1);
>> + dw_i2s_dai->capture.formats = formats[max_size];
>> + dw_i2s_dai->capture.rates = SNDRV_PCM_RATE_8000_192000;
>> + }
>> + }
>>
>> - dev->clk = clk_get(&pdev->dev, NULL);
>> - if (IS_ERR(dev->clk))
>> - return PTR_ERR(dev->clk);
>> + ret = clk_prepare(dev->clk);
>> + if (ret < 0)
>> + goto err_clk_put;
>>
>> ret = clk_enable(dev->clk);
>> if (ret < 0)
>> goto err_clk_put;
>>
>> - if (cap & DWC_I2S_PLAY) {
>> - dev_dbg(&pdev->dev, " designware: play supported\n");
>> - dw_i2s_dai->playback.channels_min = MIN_CHANNEL_NUM;
>> - dw_i2s_dai->playback.channels_max = pdata->channel;
>> - dw_i2s_dai->playback.formats = pdata->snd_fmts;
>> - dw_i2s_dai->playback.rates = pdata->snd_rates;
>> - }
>> -
>> - if (cap & DWC_I2S_RECORD) {
>> - dev_dbg(&pdev->dev, "designware: record supported\n");
>> - dw_i2s_dai->capture.channels_min = MIN_CHANNEL_NUM;
>> - dw_i2s_dai->capture.channels_max = pdata->channel;
>> - dw_i2s_dai->capture.formats = pdata->snd_fmts;
>> - dw_i2s_dai->capture.rates = pdata->snd_rates;
>> - }
>> -
>> dev->dev = &pdev->dev;
>> dev_set_drvdata(&pdev->dev, dev);
>> ret = snd_soc_register_component(&pdev->dev, &dw_i2s_component,
>> @@ -423,6 +542,15 @@ static int dw_i2s_probe(struct platform_device *pdev)
>> goto err_clk_disable;
>> }
>>
>> + if (!dev->using_pd) {
>> + ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
>> + if (ret) {
>> + dev_err(&pdev->dev,
>> + "Could not register PCM: %d\n", ret);
>> + return ret;
>> + }
>> + }
>> +
>> return 0;
>>
>> err_clk_disable:
>> @@ -443,12 +571,24 @@ static int dw_i2s_remove(struct platform_device *pdev)
>> return 0;
>> }
>>
>> +#ifdef CONFIG_OF
>> +static const struct of_device_id dw_i2s_of_match[] = {
>> + { .compatible = "snps,designware-i2s", },
>> + {},
>> +};
>> +
>> +MODULE_DEVICE_TABLE(of, dw_i2s_of_match);
>> +#endif
>> +
>> static struct platform_driver dw_i2s_driver = {
>> .probe = dw_i2s_probe,
>> .remove = dw_i2s_remove,
>> .driver = {
>> .name = "designware-i2s",
>> .owner = THIS_MODULE,
>> +#ifdef CONFIG_OF
>> + .of_match_table = dw_i2s_of_match,
>> +#endif
>> },
>> };
>>
>> --
>> 1.7.1
>>
>
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