[PATCH 4/5] ASoC: dwc: Add devicetree support for Designware I2S

From: Andrew Jackson
Date: Wed Dec 03 2014 - 11:39:47 EST


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@xxxxxxx>
---
.../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@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. */
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;
- }
-
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;
+ 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;
+ 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.
+ */
+ 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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