Implement ASoC suspend and resume callbacks to save and restore register state, to support platforms where the power is disabled during suspend.

Signed-off-by: Ed Blake ed.blake@sondrel.com --- sound/soc/img/img-i2s-in.c | 47 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+)

diff --git a/sound/soc/img/img-i2s-in.c b/sound/soc/img/img-i2s-in.c index 567f976..ebed04d 100644 --- a/sound/soc/img/img-i2s-in.c +++ b/sound/soc/img/img-i2s-in.c @@ -60,6 +60,8 @@ struct img_i2s_in { void __iomem *channel_base; unsigned int active_channels; struct snd_soc_dai_driver dai_driver; + u32 suspend_ctl; + u32 *suspend_ch_ctl; };

static inline void img_i2s_in_writel(struct img_i2s_in *i2s, u32 val, u32 reg) @@ -360,6 +362,42 @@ static int img_i2s_in_dai_probe(struct snd_soc_dai *dai) .name = "img-i2s-in" };

+static int img_i2s_in_dai_suspend(struct snd_soc_dai *dai) +{ + struct img_i2s_in *i2s = snd_soc_dai_get_drvdata(dai); + int i; + u32 reg; + + for (i = 0; i < i2s->max_i2s_chan; i++) { + reg = img_i2s_in_ch_readl(i2s, i, IMG_I2S_IN_CH_CTL); + i2s->suspend_ch_ctl[i] = reg; + } + + i2s->suspend_ctl = img_i2s_in_readl(i2s, IMG_I2S_IN_CTL); + + clk_disable_unprepare(i2s->clk_sys); + + return 0; +} + +static int img_i2s_in_dai_resume(struct snd_soc_dai *dai) +{ + struct img_i2s_in *i2s = snd_soc_dai_get_drvdata(dai); + int i; + u32 reg; + + clk_prepare_enable(i2s->clk_sys); + + for (i = 0; i < i2s->max_i2s_chan; i++) { + reg = i2s->suspend_ch_ctl[i]; + img_i2s_in_ch_writel(i2s, i, reg, IMG_I2S_IN_CH_CTL); + } + + img_i2s_in_writel(i2s, i2s->suspend_ctl, IMG_I2S_IN_CTL); + + return 0; +} + static int img_i2s_in_dma_prepare_slave_config(struct snd_pcm_substream *st, struct snd_pcm_hw_params *params, struct dma_slave_config *sc) { @@ -436,6 +474,8 @@ static int img_i2s_in_probe(struct platform_device *pdev) i2s->dma_data.addr_width = 4;

i2s->dai_driver.probe = img_i2s_in_dai_probe; + i2s->dai_driver.suspend = img_i2s_in_dai_suspend; + i2s->dai_driver.resume = img_i2s_in_dai_resume; i2s->dai_driver.capture.channels_min = 2; i2s->dai_driver.capture.channels_max = i2s->max_i2s_chan * 2; i2s->dai_driver.capture.rates = SNDRV_PCM_RATE_8000_192000; @@ -469,6 +509,13 @@ static int img_i2s_in_probe(struct platform_device *pdev) IMG_I2S_IN_CH_CTL_JUST_MASK | IMG_I2S_IN_CH_CTL_FW_MASK, IMG_I2S_IN_CH_CTL);

+ i2s->suspend_ch_ctl = devm_kzalloc(dev, + sizeof(*i2s->suspend_ch_ctl) * i2s->max_i2s_chan, GFP_KERNEL); + if (!i2s->suspend_ch_ctl) { + ret = -ENOMEM; + goto err_clk_disable; + } + ret = devm_snd_soc_register_component(dev, &img_i2s_in_component, &i2s->dai_driver, 1); if (ret)

Add runtime PM to disable the clock when the device is not in use. The ASoC core takes care of the pm_runtime_get_sync / put calls so we just need to provide runtime_suspend / runtime_resume functions and enable runtime PM.

Signed-off-by: Ed Blake ed.blake@sondrel.com --- sound/soc/img/img-i2s-in.c | 89 +++++++++++++++++++++++++++++++++++++--------- 1 file changed, 72 insertions(+), 17 deletions(-)

diff --git a/sound/soc/img/img-i2s-in.c b/sound/soc/img/img-i2s-in.c index ebed04d..45e7b1a 100644 --- a/sound/soc/img/img-i2s-in.c +++ b/sound/soc/img/img-i2s-in.c @@ -16,6 +16,7 @@ #include <linux/module.h> #include <linux/of.h> #include <linux/platform_device.h> +#include <linux/pm_runtime.h> #include <linux/reset.h>

#include <sound/core.h> @@ -64,6 +65,29 @@ struct img_i2s_in { u32 *suspend_ch_ctl; };

+static int img_i2s_in_runtime_suspend(struct device *dev) +{ + struct img_i2s_in *i2s = dev_get_drvdata(dev); + + clk_disable_unprepare(i2s->clk_sys); + + return 0; +} + +static int img_i2s_in_runtime_resume(struct device *dev) +{ + struct img_i2s_in *i2s = dev_get_drvdata(dev); + int ret; + + ret = clk_prepare_enable(i2s->clk_sys); + if (ret) { + dev_err(dev, "Unable to enable sys clock\n"); + return ret; + } + + return 0; +} + static inline void img_i2s_in_writel(struct img_i2s_in *i2s, u32 val, u32 reg) { writel(val, i2s->base + reg); @@ -321,6 +345,7 @@ static int img_i2s_in_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)

chan_control_mask = IMG_I2S_IN_CH_CTL_CLK_TRANS_MASK;

+ pm_runtime_get_sync(i2s->dev); for (i = 0; i < i2s->active_channels; i++) img_i2s_in_ch_disable(i2s, i);

@@ -340,6 +365,8 @@ static int img_i2s_in_set_fmt(struct snd_soc_dai *dai, unsigned int fmt) for (i = 0; i < i2s->active_channels; i++) img_i2s_in_ch_enable(i2s, i);

+ pm_runtime_put(i2s->dev); + return 0; }

@@ -365,9 +392,15 @@ static int img_i2s_in_dai_probe(struct snd_soc_dai *dai) static int img_i2s_in_dai_suspend(struct snd_soc_dai *dai) { struct img_i2s_in *i2s = snd_soc_dai_get_drvdata(dai); - int i; + int i, ret; u32 reg;

+ if (pm_runtime_status_suspended(i2s->dev)) { + ret = img_i2s_in_runtime_resume(i2s->dev); + if (ret) + return ret; + } + for (i = 0; i < i2s->max_i2s_chan; i++) { reg = img_i2s_in_ch_readl(i2s, i, IMG_I2S_IN_CH_CTL); i2s->suspend_ch_ctl[i] = reg; @@ -375,7 +408,7 @@ static int img_i2s_in_dai_suspend(struct snd_soc_dai *dai)

i2s->suspend_ctl = img_i2s_in_readl(i2s, IMG_I2S_IN_CTL);

- clk_disable_unprepare(i2s->clk_sys); + img_i2s_in_runtime_suspend(i2s->dev);

return 0; } @@ -383,10 +416,12 @@ static int img_i2s_in_dai_suspend(struct snd_soc_dai *dai) static int img_i2s_in_dai_resume(struct snd_soc_dai *dai) { struct img_i2s_in *i2s = snd_soc_dai_get_drvdata(dai); - int i; + int i, ret; u32 reg;

- clk_prepare_enable(i2s->clk_sys); + ret = img_i2s_in_runtime_resume(i2s->dev); + if (ret) + return ret;

for (i = 0; i < i2s->max_i2s_chan; i++) { reg = i2s->suspend_ch_ctl[i]; @@ -395,6 +430,9 @@ static int img_i2s_in_dai_resume(struct snd_soc_dai *dai)

img_i2s_in_writel(i2s, i2s->suspend_ctl, IMG_I2S_IN_CTL);

+ if (pm_runtime_status_suspended(i2s->dev)) + img_i2s_in_runtime_suspend(i2s->dev); + return 0; }

@@ -465,9 +503,15 @@ static int img_i2s_in_probe(struct platform_device *pdev) return PTR_ERR(i2s->clk_sys); }

- ret = clk_prepare_enable(i2s->clk_sys); - if (ret) - return ret; + pm_runtime_enable(&pdev->dev); + if (!pm_runtime_enabled(&pdev->dev)) { + ret = img_i2s_in_runtime_resume(&pdev->dev); + if (ret) + goto err_pm_disable; + } + ret = pm_runtime_get_sync(&pdev->dev); + if (ret < 0) + goto err_suspend;

i2s->active_channels = 1; i2s->dma_data.addr = res->start + IMG_I2S_IN_RX_FIFO; @@ -487,7 +531,7 @@ static int img_i2s_in_probe(struct platform_device *pdev) if (IS_ERR(rst)) { if (PTR_ERR(rst) == -EPROBE_DEFER) { ret = -EPROBE_DEFER; - goto err_clk_disable; + goto err_suspend; }

dev_dbg(dev, "No top level reset found\n"); @@ -509,35 +553,40 @@ static int img_i2s_in_probe(struct platform_device *pdev) IMG_I2S_IN_CH_CTL_JUST_MASK | IMG_I2S_IN_CH_CTL_FW_MASK, IMG_I2S_IN_CH_CTL);

+ pm_runtime_put(&pdev->dev); + i2s->suspend_ch_ctl = devm_kzalloc(dev, sizeof(*i2s->suspend_ch_ctl) * i2s->max_i2s_chan, GFP_KERNEL); if (!i2s->suspend_ch_ctl) { ret = -ENOMEM; - goto err_clk_disable; + goto err_suspend; }

ret = devm_snd_soc_register_component(dev, &img_i2s_in_component, &i2s->dai_driver, 1); if (ret) - goto err_clk_disable; + goto err_suspend;

ret = devm_snd_dmaengine_pcm_register(dev, &img_i2s_in_dma_config, 0); if (ret) - goto err_clk_disable; + goto err_suspend;

return 0;

-err_clk_disable: - clk_disable_unprepare(i2s->clk_sys); +err_suspend: + if (!pm_runtime_enabled(&pdev->dev)) + img_i2s_in_runtime_suspend(&pdev->dev); +err_pm_disable: + pm_runtime_disable(&pdev->dev);

return ret; }

static int img_i2s_in_dev_remove(struct platform_device *pdev) { - struct img_i2s_in *i2s = platform_get_drvdata(pdev); - - clk_disable_unprepare(i2s->clk_sys); + pm_runtime_disable(&pdev->dev); + if (!pm_runtime_status_suspended(&pdev->dev)) + img_i2s_in_runtime_suspend(&pdev->dev);

return 0; } @@ -548,10 +597,16 @@ static int img_i2s_in_dev_remove(struct platform_device *pdev) }; MODULE_DEVICE_TABLE(of, img_i2s_in_of_match);

+static const struct dev_pm_ops img_i2s_in_pm_ops = { + SET_RUNTIME_PM_OPS(img_i2s_in_runtime_suspend, + img_i2s_in_runtime_resume, NULL) +}; + static struct platform_driver img_i2s_in_driver = { .driver = { .name = "img-i2s-in", - .of_match_table = img_i2s_in_of_match + .of_match_table = img_i2s_in_of_match, + .pm = &img_i2s_in_pm_ops }, .probe = img_i2s_in_probe, .remove = img_i2s_in_dev_remove