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
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+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,
};
+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;
};
+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,
};