ASoC: kirkwood-i2s: add support for external clock rates
This is part of a patch found in Rabeeh Khoury's git tree for the
cubox, and cleaned up by me.
Some platforms provide an external clock which can be used to allow
other sample rates to be selected. Provide support for this.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/kirkwood/kirkwood-i2s.c b/sound/soc/kirkwood/kirkwood-i2s.c
index 823ef1e..d3629d5 100644
--- a/sound/soc/kirkwood/kirkwood-i2s.c
+++ b/sound/soc/kirkwood/kirkwood-i2s.c
@@ -99,6 +99,29 @@
} while (value == 0);
}
+static void kirkwood_set_rate(struct snd_soc_dai *dai,
+ struct kirkwood_dma_data *priv, unsigned long rate)
+{
+ uint32_t clks_ctrl;
+
+ if (rate == 44100 || rate == 48000 || rate == 96000) {
+ /* use internal dco for supported rates */
+ dev_dbg(dai->dev, "%s: dco set rate = %lu\n",
+ __func__, rate);
+ kirkwood_set_dco(priv->io, rate);
+
+ clks_ctrl = KIRKWOOD_MCLK_SOURCE_DCO;
+ } else if (!IS_ERR(priv->extclk)) {
+ /* use optional external clk for other rates */
+ dev_dbg(dai->dev, "%s: extclk set rate = %lu -> %lu\n",
+ __func__, rate, 256 * rate);
+ clk_set_rate(priv->extclk, 256 * rate);
+
+ clks_ctrl = KIRKWOOD_MCLK_SOURCE_EXTCLK;
+ }
+ writel(clks_ctrl, priv->io + KIRKWOOD_CLOCKS_CTRL);
+}
+
static int kirkwood_i2s_startup(struct snd_pcm_substream *substream,
struct snd_soc_dai *dai)
{
@@ -123,8 +146,7 @@
i2s_reg = KIRKWOOD_I2S_RECCTL;
}
- /* set dco conf */
- kirkwood_set_dco(priv->io, params_rate(params));
+ kirkwood_set_rate(dai, priv, params_rate(params));
i2s_value = readl(priv->io+i2s_reg);
i2s_value &= ~KIRKWOOD_I2S_CTL_SIZE_MASK;
@@ -396,21 +418,45 @@
.channels_min = 1,
.channels_max = 2,
.rates = KIRKWOOD_I2S_RATES,
- .formats = KIRKWOOD_I2S_FORMATS,},
+ .formats = KIRKWOOD_I2S_FORMATS,
+ },
.capture = {
.channels_min = 1,
.channels_max = 2,
.rates = KIRKWOOD_I2S_RATES,
- .formats = KIRKWOOD_I2S_FORMATS,},
+ .formats = KIRKWOOD_I2S_FORMATS,
+ },
+ .ops = &kirkwood_i2s_dai_ops,
+};
+
+static struct snd_soc_dai_driver kirkwood_i2s_dai_extclk = {
+ .probe = kirkwood_i2s_probe,
+ .remove = kirkwood_i2s_remove,
+ .playback = {
+ .channels_min = 1,
+ .channels_max = 2,
+ .rates = SNDRV_PCM_RATE_8000_192000 |
+ SNDRV_PCM_RATE_CONTINUOUS |
+ SNDRV_PCM_RATE_KNOT,
+ .formats = KIRKWOOD_I2S_FORMATS,
+ },
+ .capture = {
+ .channels_min = 1,
+ .channels_max = 2,
+ .rates = SNDRV_PCM_RATE_8000_192000 |
+ SNDRV_PCM_RATE_CONTINUOUS |
+ SNDRV_PCM_RATE_KNOT,
+ .formats = KIRKWOOD_I2S_FORMATS,
+ },
.ops = &kirkwood_i2s_dai_ops,
};
static __devinit int kirkwood_i2s_dev_probe(struct platform_device *pdev)
{
- struct resource *mem;
- struct kirkwood_asoc_platform_data *data =
- pdev->dev.platform_data;
+ struct kirkwood_asoc_platform_data *data = pdev->dev.platform_data;
+ struct snd_soc_dai_driver *soc_dai = &kirkwood_i2s_dai;
struct kirkwood_dma_data *priv;
+ struct resource *mem;
int err;
priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
@@ -480,11 +526,15 @@
priv->ctl_rec |= KIRKWOOD_RECCTL_BURST_128;
}
- err = snd_soc_register_dai(&pdev->dev, &kirkwood_i2s_dai);
+ err = snd_soc_register_dai(&pdev->dev, soc_dai);
if (!err)
return 0;
dev_err(&pdev->dev, "snd_soc_register_dai failed\n");
+ if (!IS_ERR(priv->extclk)) {
+ clk_disable_unprepare(priv->extclk);
+ clk_put(priv->extclk);
+ }
clk_disable_unprepare(priv->clk);
return err;
@@ -496,6 +546,10 @@
snd_soc_unregister_dai(&pdev->dev);
+ if (!IS_ERR(priv->extclk)) {
+ clk_disable_unprepare(priv->extclk);
+ clk_put(priv->extclk);
+ }
clk_disable_unprepare(priv->clk);
return 0;