Unverified Commit cf881773 authored by Olivier Moysan's avatar Olivier Moysan Committed by Mark Brown
Browse files

ASoC: stm32: sai: add power management 



Add support of low power modes to STM32 SAI driver.

Signed-off-by: default avatarOlivier Moysan <olivier.moysan@st.com>
Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent eddb6084

sound/soc/stm/stm32_sai.c

+71 −9
Original line number Diff line number Diff line
@@ -21,6 +21,7 @@ 
#include <linux/delay.h>

#include <linux/module.h>

#include <linux/of_platform.h>

#include <linux/pinctrl/consumer.h>

#include <linux/reset.h>



#include <sound/dmaengine_pcm.h>
@@ -44,20 +45,41 @@ static const struct of_device_id stm32_sai_ids[] = { 
	{}

};



static int stm32_sai_sync_conf_client(struct stm32_sai_data *sai, int synci)

static int stm32_sai_pclk_disable(struct device *dev)

{

	struct stm32_sai_data *sai = dev_get_drvdata(dev);



	clk_disable_unprepare(sai->pclk);



	return 0;

}



static int stm32_sai_pclk_enable(struct device *dev)

{

	struct stm32_sai_data *sai = dev_get_drvdata(dev);

	int ret;



	/* Enable peripheral clock to allow GCR register access */

	ret = clk_prepare_enable(sai->pclk);

	if (ret) {

		dev_err(&sai->pdev->dev, "failed to enable clock: %d\n", ret);

		return ret;

	}



	return 0;

}



static int stm32_sai_sync_conf_client(struct stm32_sai_data *sai, int synci)

{

	int ret;



	/* Enable peripheral clock to allow GCR register access */

	ret = stm32_sai_pclk_enable(&sai->pdev->dev);

	if (ret)

		return ret;



	writel_relaxed(FIELD_PREP(SAI_GCR_SYNCIN_MASK, (synci - 1)), sai->base);



	clk_disable_unprepare(sai->pclk);

	stm32_sai_pclk_disable(&sai->pdev->dev);



	return 0;

}
@@ -68,11 +90,9 @@ static int stm32_sai_sync_conf_provider(struct stm32_sai_data *sai, int synco) 
	int ret;



	/* Enable peripheral clock to allow GCR register access */

	ret = clk_prepare_enable(sai->pclk);

	if (ret) {

		dev_err(&sai->pdev->dev, "failed to enable clock: %d\n", ret);

	ret = stm32_sai_pclk_enable(&sai->pdev->dev);

	if (ret)

		return ret;

	}



	dev_dbg(&sai->pdev->dev, "Set %pOFn%s as synchro provider\n",

		sai->pdev->dev.of_node,
@@ -83,13 +103,13 @@ static int stm32_sai_sync_conf_provider(struct stm32_sai_data *sai, int synco) 
		dev_err(&sai->pdev->dev, "%pOFn%s already set as sync provider\n",

			sai->pdev->dev.of_node,

			prev_synco == STM_SAI_SYNC_OUT_A ? "A" : "B");

		clk_disable_unprepare(sai->pclk);

			stm32_sai_pclk_disable(&sai->pdev->dev);

		return -EINVAL;

	}



	writel_relaxed(FIELD_PREP(SAI_GCR_SYNCOUT_MASK, synco), sai->base);



	clk_disable_unprepare(sai->pclk);

	stm32_sai_pclk_disable(&sai->pdev->dev);



	return 0;

}
@@ -195,12 +215,54 @@ static int stm32_sai_probe(struct platform_device *pdev) 
	return devm_of_platform_populate(&pdev->dev);

}



#ifdef CONFIG_PM_SLEEP

/*

 * When pins are shared by two sai sub instances, pins have to be defined

 * in sai parent node. In this case, pins state is not managed by alsa fw.

 * These pins are managed in suspend/resume callbacks.

 */

static int stm32_sai_suspend(struct device *dev)

{

	struct stm32_sai_data *sai = dev_get_drvdata(dev);

	int ret;



	ret = stm32_sai_pclk_enable(dev);

	if (ret)

		return ret;



	sai->gcr = readl_relaxed(sai->base);

	stm32_sai_pclk_disable(dev);



	return pinctrl_pm_select_sleep_state(dev);

}



static int stm32_sai_resume(struct device *dev)

{

	struct stm32_sai_data *sai = dev_get_drvdata(dev);

	int ret;



	ret = stm32_sai_pclk_enable(dev);

	if (ret)

		return ret;



	writel_relaxed(sai->gcr, sai->base);

	stm32_sai_pclk_disable(dev);



	return pinctrl_pm_select_default_state(dev);

}

#endif /* CONFIG_PM_SLEEP */



static const struct dev_pm_ops stm32_sai_pm_ops = {

	SET_SYSTEM_SLEEP_PM_OPS(stm32_sai_suspend, stm32_sai_resume)

};



MODULE_DEVICE_TABLE(of, stm32_sai_ids);



static struct platform_driver stm32_sai_driver = {

	.driver = {

		.name = "st,stm32-sai",

		.of_match_table = stm32_sai_ids,

		.pm = &stm32_sai_pm_ops,

	},

	.probe = stm32_sai_probe,

};

sound/soc/stm/stm32_sai.h

+2 −0
Original line number Diff line number Diff line
@@ -268,6 +268,7 @@ struct stm32_sai_conf { 
 * @version: SOC version

 * @irq: SAI interrupt line

 * @set_sync: pointer to synchro mode configuration callback

 * @gcr: SAI Global Configuration Register

 */

struct stm32_sai_data {

	struct platform_device *pdev;
@@ -279,4 +280,5 @@ struct stm32_sai_data { 
	int irq;

	int (*set_sync)(struct stm32_sai_data *sai,

			struct device_node *np_provider, int synco, int synci);

	u32 gcr;

};

sound/soc/stm/stm32_sai_sub.c

+35 −10
Original line number Diff line number Diff line
@@ -168,6 +168,7 @@ static bool stm32_sai_sub_volatile_reg(struct device *dev, unsigned int reg) 
{

	switch (reg) {

	case STM_SAI_DR_REGX:

	case STM_SAI_SR_REGX:

		return true;

	default:

		return false;
@@ -182,7 +183,6 @@ static bool stm32_sai_sub_writeable_reg(struct device *dev, unsigned int reg) 
	case STM_SAI_FRCR_REGX:

	case STM_SAI_SLOTR_REGX:

	case STM_SAI_IMR_REGX:

	case STM_SAI_SR_REGX:

	case STM_SAI_CLRFR_REGX:

	case STM_SAI_DR_REGX:

	case STM_SAI_PDMCR_REGX:
@@ -202,6 +202,7 @@ static const struct regmap_config stm32_sai_sub_regmap_config_f4 = { 
	.volatile_reg = stm32_sai_sub_volatile_reg,

	.writeable_reg = stm32_sai_sub_writeable_reg,

	.fast_io = true,

	.cache_type = REGCACHE_FLAT,

};



static const struct regmap_config stm32_sai_sub_regmap_config_h7 = {
@@ -213,6 +214,7 @@ static const struct regmap_config stm32_sai_sub_regmap_config_h7 = { 
	.volatile_reg = stm32_sai_sub_volatile_reg,

	.writeable_reg = stm32_sai_sub_writeable_reg,

	.fast_io = true,

	.cache_type = REGCACHE_FLAT,

};



static int snd_pcm_iec958_info(struct snd_kcontrol *kcontrol,
@@ -441,7 +443,7 @@ static irqreturn_t stm32_sai_isr(int irq, void *devid) 
	if (!flags)

		return IRQ_NONE;



	regmap_update_bits(sai->regmap, STM_SAI_CLRFR_REGX, SAI_XCLRFR_MASK,

	regmap_write_bits(sai->regmap, STM_SAI_CLRFR_REGX, SAI_XCLRFR_MASK,

			  SAI_XCLRFR_MASK);



	if (!sai->substream) {
@@ -704,8 +706,7 @@ static int stm32_sai_startup(struct snd_pcm_substream *substream, 
	}



	/* Enable ITs */



	regmap_update_bits(sai->regmap, STM_SAI_CLRFR_REGX,

	regmap_write_bits(sai->regmap, STM_SAI_CLRFR_REGX,

			  SAI_XCLRFR_MASK, SAI_XCLRFR_MASK);



	imr = SAI_XIMR_OVRUDRIE;
@@ -738,7 +739,7 @@ static int stm32_sai_set_config(struct snd_soc_dai *cpu_dai, 
	 * SAI fifo threshold is set to half fifo, to keep enough space

	 * for DMA incoming bursts.

	 */

	regmap_update_bits(sai->regmap, STM_SAI_CR2_REGX,

	regmap_write_bits(sai->regmap, STM_SAI_CR2_REGX,

			  SAI_XCR2_FFLUSH | SAI_XCR2_FTH_MASK,

			  SAI_XCR2_FFLUSH |

			  SAI_XCR2_FTH_SET(STM_SAI_FIFO_TH_HALF));
@@ -1492,10 +1493,34 @@ static int stm32_sai_sub_probe(struct platform_device *pdev) 
	return 0;

}



#ifdef CONFIG_PM_SLEEP

static int stm32_sai_sub_suspend(struct device *dev)

{

	struct stm32_sai_sub_data *sai = dev_get_drvdata(dev);



	regcache_cache_only(sai->regmap, true);

	regcache_mark_dirty(sai->regmap);

	return 0;

}



static int stm32_sai_sub_resume(struct device *dev)

{

	struct stm32_sai_sub_data *sai = dev_get_drvdata(dev);



	regcache_cache_only(sai->regmap, false);

	return regcache_sync(sai->regmap);

}

#endif /* CONFIG_PM_SLEEP */



static const struct dev_pm_ops stm32_sai_sub_pm_ops = {

	SET_SYSTEM_SLEEP_PM_OPS(stm32_sai_sub_suspend, stm32_sai_sub_resume)

};



static struct platform_driver stm32_sai_sub_driver = {

	.driver = {

		.name = "st,stm32-sai-sub",

		.of_match_table = stm32_sai_sub_ids,

		.pm = &stm32_sai_sub_pm_ops,

	},

	.probe = stm32_sai_sub_probe,

};