[PATCH] ASoC: axi-i2s: let both capture and playback be optional

From: Luca Ceresoli
Date: Thu Mar 07 2019 - 16:44:55 EST


Both the capture and playback channels are optional in the axi_i2s IP
block. Reflect this in the driver by enabling only the channel(s) that
have a DMA.

Signed-off-by: Luca Ceresoli <luca@xxxxxxxxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
sound/soc/adi/axi-i2s.c | 68 +++++++++++++++++++++++++++++------------
1 file changed, 48 insertions(+), 20 deletions(-)

diff --git a/sound/soc/adi/axi-i2s.c b/sound/soc/adi/axi-i2s.c
index 4c23381727a1..273c543e8ff3 100644
--- a/sound/soc/adi/axi-i2s.c
+++ b/sound/soc/adi/axi-i2s.c
@@ -43,6 +43,9 @@ struct axi_i2s {
struct clk *clk;
struct clk *clk_ref;

+ bool has_capture;
+ bool has_playback;
+
struct snd_soc_dai_driver dai_driver;

struct snd_dmaengine_dai_dma_data capture_dma_data;
@@ -136,8 +139,10 @@ static int axi_i2s_dai_probe(struct snd_soc_dai *dai)
{
struct axi_i2s *i2s = snd_soc_dai_get_drvdata(dai);

- snd_soc_dai_init_dma_data(dai, &i2s->playback_dma_data,
- &i2s->capture_dma_data);
+ snd_soc_dai_init_dma_data(
+ dai,
+ i2s->has_playback ? &i2s->playback_dma_data : NULL,
+ i2s->has_capture ? &i2s->capture_dma_data : NULL);

return 0;
}
@@ -151,18 +156,6 @@ static const struct snd_soc_dai_ops axi_i2s_dai_ops = {

static struct snd_soc_dai_driver axi_i2s_dai = {
.probe = axi_i2s_dai_probe,
- .playback = {
- .channels_min = 2,
- .channels_max = 2,
- .rates = SNDRV_PCM_RATE_KNOT,
- .formats = SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_U32_LE,
- },
- .capture = {
- .channels_min = 2,
- .channels_max = 2,
- .rates = SNDRV_PCM_RATE_KNOT,
- .formats = SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_U32_LE,
- },
.ops = &axi_i2s_dai_ops,
.symmetric_rates = 1,
};
@@ -178,6 +171,19 @@ static const struct regmap_config axi_i2s_regmap_config = {
.max_register = AXI_I2S_REG_STATUS,
};

+static void axi_i2s_parse_of(struct axi_i2s *i2s, const struct device_node *np)
+{
+ struct property *dma_names;
+ const char *dma_name;
+
+ of_property_for_each_string(np, "dma-names", dma_names, dma_name) {
+ if (strcmp(dma_name, "rx") == 0)
+ i2s->has_capture = true;
+ if (strcmp(dma_name, "tx") == 0)
+ i2s->has_playback = true;
+ }
+}
+
static int axi_i2s_probe(struct platform_device *pdev)
{
struct resource *res;
@@ -191,6 +197,8 @@ static int axi_i2s_probe(struct platform_device *pdev)

platform_set_drvdata(pdev, i2s);

+ axi_i2s_parse_of(i2s, pdev->dev.of_node);
+
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(base))
@@ -213,13 +221,29 @@ static int axi_i2s_probe(struct platform_device *pdev)
if (ret)
return ret;

- i2s->playback_dma_data.addr = res->start + AXI_I2S_REG_TX_FIFO;
- i2s->playback_dma_data.addr_width = 4;
- i2s->playback_dma_data.maxburst = 1;
+ if (i2s->has_playback) {
+ axi_i2s_dai.playback.channels_min = 2;
+ axi_i2s_dai.playback.channels_max = 2;
+ axi_i2s_dai.playback.rates = SNDRV_PCM_RATE_KNOT;
+ axi_i2s_dai.playback.formats =
+ SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_U32_LE;
+
+ i2s->playback_dma_data.addr = res->start + AXI_I2S_REG_TX_FIFO;
+ i2s->playback_dma_data.addr_width = 4;
+ i2s->playback_dma_data.maxburst = 1;
+ }
+
+ if (i2s->has_capture) {
+ axi_i2s_dai.capture.channels_min = 2;
+ axi_i2s_dai.capture.channels_max = 2;
+ axi_i2s_dai.capture.rates = SNDRV_PCM_RATE_KNOT;
+ axi_i2s_dai.capture.formats =
+ SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_U32_LE;

- i2s->capture_dma_data.addr = res->start + AXI_I2S_REG_RX_FIFO;
- i2s->capture_dma_data.addr_width = 4;
- i2s->capture_dma_data.maxburst = 1;
+ i2s->capture_dma_data.addr = res->start + AXI_I2S_REG_RX_FIFO;
+ i2s->capture_dma_data.addr_width = 4;
+ i2s->capture_dma_data.maxburst = 1;
+ }

i2s->ratnum.num = clk_get_rate(i2s->clk_ref) / 2 / AXI_I2S_BITS_PER_FRAME;
i2s->ratnum.den_step = 1;
@@ -240,6 +264,10 @@ static int axi_i2s_probe(struct platform_device *pdev)
if (ret)
goto err_clk_disable;

+ dev_info(&pdev->dev, "probed, capture %s, playback %s\n",
+ i2s->has_capture ? "enabled" : "disabled",
+ i2s->has_playback ? "enabled" : "disabled");
+
return 0;

err_clk_disable:
--
2.20.1