Hi Daniel,
On Du, 2019-04-21 at 19:39 +0000, Daniel Baluta wrote:
From: Shengjiu Wang shengjiu.wang@nxp.com
Turn off/on clocks when device enters suspend/resume. This can help saving power.
As a further optimization, we turn off/on mclk only when SAI is in master mode because otherwise mclk is externally provided.
Signed-off-by: Shengjiu Wang shengjiu.wang@nxp.com Signed-off-by: Daniel Baluta daniel.baluta@nxp.com
sound/soc/fsl/fsl_sai.c | 60 ++++++++++++++++++++++++++++++++++------- 1 file changed, 50 insertions(+), 10 deletions(-)
diff --git a/sound/soc/fsl/fsl_sai.c b/sound/soc/fsl/fsl_sai.c index 8623b7f882b9..13a462360ed3 100644 --- a/sound/soc/fsl/fsl_sai.c +++ b/sound/soc/fsl/fsl_sai.c @@ -596,15 +596,8 @@ static int fsl_sai_startup(struct snd_pcm_substream *substream, { struct fsl_sai *sai = snd_soc_dai_get_drvdata(cpu_dai); bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
- struct device *dev = &sai->pdev->dev;
int ret;
- ret = clk_prepare_enable(sai->bus_clk);
- if (ret) {
dev_err(dev, "failed to enable bus clock: %d\n", ret);return ret;- }
regmap_update_bits(sai->regmap, FSL_SAI_xCR3(tx), FSL_SAI_CR3_TRCE, FSL_SAI_CR3_TRCE); @@ -621,8 +614,6 @@ static void fsl_sai_shutdown(struct snd_pcm_substream *substream, bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK; regmap_update_bits(sai->regmap, FSL_SAI_xCR3(tx), FSL_SAI_CR3_TRCE, 0);
- clk_disable_unprepare(sai->bus_clk);
} static const struct snd_soc_dai_ops fsl_sai_pcm_dai_ops = { @@ -932,6 +923,16 @@ static int fsl_sai_runtime_suspend(struct device *dev) { struct fsl_sai *sai = dev_get_drvdata(dev);
- if (!sai->is_slave_mode) {
This check is redundant as the bits in sai->mclk_streams are set/unset for master mode only, please check fsl_sai_hw_params and fsl_sai_hw_free functions.
if (sai->mclk_streams & BIT(SNDRV_PCM_STREAM_CAPTURE))clk_disable_unprepare(sai->mclk_clk[sai->mclk_id[0]]);if (sai->mclk_streams & BIT(SNDRV_PCM_STREAM_PLAYBACK))clk_disable_unprepare(sai->mclk_clk[sai->mclk_id[1]]);- }
- clk_disable_unprepare(sai->bus_clk);
regcache_cache_only(sai->regmap, true); regcache_mark_dirty(sai->regmap); @@ -941,6 +942,27 @@ static int fsl_sai_runtime_suspend(struct device *dev) static int fsl_sai_runtime_resume(struct device *dev) { struct fsl_sai *sai = dev_get_drvdata(dev);
- int ret;
- ret = clk_prepare_enable(sai->bus_clk);
- if (ret) {
dev_err(dev, "failed to enable bus clock: %d\n", ret);return ret;- }
- if (!sai->is_slave_mode) {
if (sai->mclk_streams & BIT(SNDRV_PCM_STREAM_PLAYBACK)) {ret = clk_prepare_enable(sai->mclk_clk[sai->mclk_id[1]]);if (ret)goto disable_bus_clk;}if (sai->mclk_streams & BIT(SNDRV_PCM_STREAM_CAPTURE)) {ret = clk_prepare_enable(sai->mclk_clk[sai->mclk_id[0]]);if (ret)goto disable_tx_clk;}- }
regcache_cache_only(sai->regmap, false); regmap_write(sai->regmap, FSL_SAI_TCSR, FSL_SAI_CSR_SR); @@ -948,7 +970,25 @@ static int fsl_sai_runtime_resume(struct device *dev) usleep_range(1000, 2000); regmap_write(sai->regmap, FSL_SAI_TCSR, 0); regmap_write(sai->regmap, FSL_SAI_RCSR, 0);
- return regcache_sync(sai->regmap);
- ret = regcache_sync(sai->regmap);
- if (ret)
goto disable_rx_clk;- return 0;
+disable_rx_clk:
- if (!sai->is_slave_mode &&
- (sai->mclk_streams & BIT(SNDRV_PCM_STREAM_CAPTURE)))
clk_disable_unprepare(sai->mclk_clk[sai->mclk_id[0]]);+disable_tx_clk:
- if (!sai->is_slave_mode &&
- (sai->mclk_streams & BIT(SNDRV_PCM_STREAM_PLAYBACK)))
clk_disable_unprepare(sai->mclk_clk[sai->mclk_id[1]]);+disable_bus_clk:
- clk_disable_unprepare(sai->bus_clk);
- return ret;
} #endif /* CONFIG_PM */ -- 2.17.1