diff mbox series

iio: adc: stm32-dfsdm: add PM support

Message ID 1553525368-23419-1-git-send-email-fabrice.gasnier@st.com (mailing list archive)
State Mainlined, archived
Commit 6ec417d2f1a028705a1ae6f59d3e15344f6a4fbe
Headers show
Series iio: adc: stm32-dfsdm: add PM support | expand

Commit Message

Fabrice Gasnier March 25, 2019, 2:49 p.m. UTC
Add PM and runtime PM support to STM32 DFSDM drivers:
- stm32-dfsdm-core: manage clocks.
- stm32-dfsdm-adc: restore channels configuration upon resume. Also stop
  restart everything in case of buffer mode.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
---
 drivers/iio/adc/stm32-dfsdm-adc.c  |  75 +++++++++++++++--
 drivers/iio/adc/stm32-dfsdm-core.c | 163 +++++++++++++++++++++++++++++++------
 2 files changed, 206 insertions(+), 32 deletions(-)

Comments

Jonathan Cameron March 31, 2019, 10:03 a.m. UTC | #1
On Mon, 25 Mar 2019 15:49:28 +0100
Fabrice Gasnier <fabrice.gasnier@st.com> wrote:

> Add PM and runtime PM support to STM32 DFSDM drivers:
> - stm32-dfsdm-core: manage clocks.
> - stm32-dfsdm-adc: restore channels configuration upon resume. Also stop
>   restart everything in case of buffer mode.
> 
> Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
I'll confess that power management code always gives me a headache, but
I 'think' this looks right.

Applied to the togreg branch of iio.git and pushed out as testing for
the autobuilders to play with it.

Thanks,

Jonathan

> ---
>  drivers/iio/adc/stm32-dfsdm-adc.c  |  75 +++++++++++++++--
>  drivers/iio/adc/stm32-dfsdm-core.c | 163 +++++++++++++++++++++++++++++++------
>  2 files changed, 206 insertions(+), 32 deletions(-)
> 
> diff --git a/drivers/iio/adc/stm32-dfsdm-adc.c b/drivers/iio/adc/stm32-dfsdm-adc.c
> index 531ca7e..a599097 100644
> --- a/drivers/iio/adc/stm32-dfsdm-adc.c
> +++ b/drivers/iio/adc/stm32-dfsdm-adc.c
> @@ -851,24 +851,18 @@ static int stm32_dfsdm_update_scan_mode(struct iio_dev *indio_dev,
>  	return 0;
>  }
>  
> -static int stm32_dfsdm_postenable(struct iio_dev *indio_dev)
> +static int __stm32_dfsdm_postenable(struct iio_dev *indio_dev)
>  {
>  	struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
>  	int ret;
>  
> -	if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED) {
> -		ret = iio_triggered_buffer_postenable(indio_dev);
> -		if (ret < 0)
> -			return ret;
> -	}
> -
>  	/* Reset adc buffer index */
>  	adc->bufi = 0;
>  
>  	if (adc->hwc) {
>  		ret = iio_hw_consumer_enable(adc->hwc);
>  		if (ret < 0)
> -			goto err_predisable;
> +			return ret;
>  	}
>  
>  	ret = stm32_dfsdm_start_dfsdm(adc->dfsdm);
> @@ -896,6 +890,26 @@ static int stm32_dfsdm_postenable(struct iio_dev *indio_dev)
>  err_stop_hwc:
>  	if (adc->hwc)
>  		iio_hw_consumer_disable(adc->hwc);
> +
> +	return ret;
> +}
> +
> +static int stm32_dfsdm_postenable(struct iio_dev *indio_dev)
> +{
> +	int ret;
> +
> +	if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED) {
> +		ret = iio_triggered_buffer_postenable(indio_dev);
> +		if (ret < 0)
> +			return ret;
> +	}
> +
> +	ret = __stm32_dfsdm_postenable(indio_dev);
> +	if (ret < 0)
> +		goto err_predisable;
> +
> +	return 0;
> +
>  err_predisable:
>  	if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED)
>  		iio_triggered_buffer_predisable(indio_dev);
> @@ -903,7 +917,7 @@ static int stm32_dfsdm_postenable(struct iio_dev *indio_dev)
>  	return ret;
>  }
>  
> -static int stm32_dfsdm_predisable(struct iio_dev *indio_dev)
> +static void __stm32_dfsdm_predisable(struct iio_dev *indio_dev)
>  {
>  	struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
>  
> @@ -915,6 +929,11 @@ static int stm32_dfsdm_predisable(struct iio_dev *indio_dev)
>  
>  	if (adc->hwc)
>  		iio_hw_consumer_disable(adc->hwc);
> +}
> +
> +static int stm32_dfsdm_predisable(struct iio_dev *indio_dev)
> +{
> +	__stm32_dfsdm_predisable(indio_dev);
>  
>  	if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED)
>  		iio_triggered_buffer_predisable(indio_dev);
> @@ -1492,10 +1511,48 @@ static int stm32_dfsdm_adc_remove(struct platform_device *pdev)
>  	return 0;
>  }
>  
> +static int __maybe_unused stm32_dfsdm_adc_suspend(struct device *dev)
> +{
> +	struct stm32_dfsdm_adc *adc = dev_get_drvdata(dev);
> +	struct iio_dev *indio_dev = iio_priv_to_dev(adc);
> +
> +	if (iio_buffer_enabled(indio_dev))
> +		__stm32_dfsdm_predisable(indio_dev);
> +
> +	return 0;
> +}
> +
> +static int __maybe_unused stm32_dfsdm_adc_resume(struct device *dev)
> +{
> +	struct stm32_dfsdm_adc *adc = dev_get_drvdata(dev);
> +	struct iio_dev *indio_dev = iio_priv_to_dev(adc);
> +	const struct iio_chan_spec *chan;
> +	struct stm32_dfsdm_channel *ch;
> +	int i, ret;
> +
> +	/* restore channels configuration */
> +	for (i = 0; i < indio_dev->num_channels; i++) {
> +		chan = indio_dev->channels + i;
> +		ch = &adc->dfsdm->ch_list[chan->channel];
> +		ret = stm32_dfsdm_chan_configure(adc->dfsdm, ch);
> +		if (ret)
> +			return ret;
> +	}
> +
> +	if (iio_buffer_enabled(indio_dev))
> +		__stm32_dfsdm_postenable(indio_dev);
> +
> +	return 0;
> +}
> +
> +static SIMPLE_DEV_PM_OPS(stm32_dfsdm_adc_pm_ops,
> +			 stm32_dfsdm_adc_suspend, stm32_dfsdm_adc_resume);
> +
>  static struct platform_driver stm32_dfsdm_adc_driver = {
>  	.driver = {
>  		.name = "stm32-dfsdm-adc",
>  		.of_match_table = stm32_dfsdm_adc_match,
> +		.pm = &stm32_dfsdm_adc_pm_ops,
>  	},
>  	.probe = stm32_dfsdm_adc_probe,
>  	.remove = stm32_dfsdm_adc_remove,
> diff --git a/drivers/iio/adc/stm32-dfsdm-core.c b/drivers/iio/adc/stm32-dfsdm-core.c
> index 472b809..0a4d374 100644
> --- a/drivers/iio/adc/stm32-dfsdm-core.c
> +++ b/drivers/iio/adc/stm32-dfsdm-core.c
> @@ -12,6 +12,8 @@
>  #include <linux/interrupt.h>
>  #include <linux/module.h>
>  #include <linux/of_device.h>
> +#include <linux/pinctrl/consumer.h>
> +#include <linux/pm_runtime.h>
>  #include <linux/regmap.h>
>  #include <linux/slab.h>
>  
> @@ -90,6 +92,36 @@ struct dfsdm_priv {
>  	struct clk *aclk; /* audio clock */
>  };
>  
> +static inline struct dfsdm_priv *to_stm32_dfsdm_priv(struct stm32_dfsdm *dfsdm)
> +{
> +	return container_of(dfsdm, struct dfsdm_priv, dfsdm);
> +}
> +
> +static int stm32_dfsdm_clk_prepare_enable(struct stm32_dfsdm *dfsdm)
> +{
> +	struct dfsdm_priv *priv = to_stm32_dfsdm_priv(dfsdm);
> +	int ret;
> +
> +	ret = clk_prepare_enable(priv->clk);
> +	if (ret || !priv->aclk)
> +		return ret;
> +
> +	ret = clk_prepare_enable(priv->aclk);
> +	if (ret)
> +		clk_disable_unprepare(priv->clk);
> +
> +	return ret;
> +}
> +
> +static void stm32_dfsdm_clk_disable_unprepare(struct stm32_dfsdm *dfsdm)
> +{
> +	struct dfsdm_priv *priv = to_stm32_dfsdm_priv(dfsdm);
> +
> +	if (priv->aclk)
> +		clk_disable_unprepare(priv->aclk);
> +	clk_disable_unprepare(priv->clk);
> +}
> +
>  /**
>   * stm32_dfsdm_start_dfsdm - start global dfsdm interface.
>   *
> @@ -98,24 +130,17 @@ struct dfsdm_priv {
>   */
>  int stm32_dfsdm_start_dfsdm(struct stm32_dfsdm *dfsdm)
>  {
> -	struct dfsdm_priv *priv = container_of(dfsdm, struct dfsdm_priv, dfsdm);
> +	struct dfsdm_priv *priv = to_stm32_dfsdm_priv(dfsdm);
>  	struct device *dev = &priv->pdev->dev;
>  	unsigned int clk_div = priv->spi_clk_out_div, clk_src;
>  	int ret;
>  
>  	if (atomic_inc_return(&priv->n_active_ch) == 1) {
> -		ret = clk_prepare_enable(priv->clk);
> +		ret = pm_runtime_get_sync(dev);
>  		if (ret < 0) {
> -			dev_err(dev, "Failed to start clock\n");
> +			pm_runtime_put_noidle(dev);
>  			goto error_ret;
>  		}
> -		if (priv->aclk) {
> -			ret = clk_prepare_enable(priv->aclk);
> -			if (ret < 0) {
> -				dev_err(dev, "Failed to start audio clock\n");
> -				goto disable_clk;
> -			}
> -		}
>  
>  		/* select clock source, e.g. 0 for "dfsdm" or 1 for "audio" */
>  		clk_src = priv->aclk ? 1 : 0;
> @@ -123,21 +148,21 @@ int stm32_dfsdm_start_dfsdm(struct stm32_dfsdm *dfsdm)
>  					 DFSDM_CHCFGR1_CKOUTSRC_MASK,
>  					 DFSDM_CHCFGR1_CKOUTSRC(clk_src));
>  		if (ret < 0)
> -			goto disable_aclk;
> +			goto pm_put;
>  
>  		/* Output the SPI CLKOUT (if clk_div == 0 clock if OFF) */
>  		ret = regmap_update_bits(dfsdm->regmap, DFSDM_CHCFGR1(0),
>  					 DFSDM_CHCFGR1_CKOUTDIV_MASK,
>  					 DFSDM_CHCFGR1_CKOUTDIV(clk_div));
>  		if (ret < 0)
> -			goto disable_aclk;
> +			goto pm_put;
>  
>  		/* Global enable of DFSDM interface */
>  		ret = regmap_update_bits(dfsdm->regmap, DFSDM_CHCFGR1(0),
>  					 DFSDM_CHCFGR1_DFSDMEN_MASK,
>  					 DFSDM_CHCFGR1_DFSDMEN(1));
>  		if (ret < 0)
> -			goto disable_aclk;
> +			goto pm_put;
>  	}
>  
>  	dev_dbg(dev, "%s: n_active_ch %d\n", __func__,
> @@ -145,11 +170,8 @@ int stm32_dfsdm_start_dfsdm(struct stm32_dfsdm *dfsdm)
>  
>  	return 0;
>  
> -disable_aclk:
> -	clk_disable_unprepare(priv->aclk);
> -disable_clk:
> -	clk_disable_unprepare(priv->clk);
> -
> +pm_put:
> +	pm_runtime_put_sync(dev);
>  error_ret:
>  	atomic_dec(&priv->n_active_ch);
>  
> @@ -165,7 +187,7 @@ EXPORT_SYMBOL_GPL(stm32_dfsdm_start_dfsdm);
>   */
>  int stm32_dfsdm_stop_dfsdm(struct stm32_dfsdm *dfsdm)
>  {
> -	struct dfsdm_priv *priv = container_of(dfsdm, struct dfsdm_priv, dfsdm);
> +	struct dfsdm_priv *priv = to_stm32_dfsdm_priv(dfsdm);
>  	int ret;
>  
>  	if (atomic_dec_and_test(&priv->n_active_ch)) {
> @@ -183,9 +205,7 @@ int stm32_dfsdm_stop_dfsdm(struct stm32_dfsdm *dfsdm)
>  		if (ret < 0)
>  			return ret;
>  
> -		clk_disable_unprepare(priv->clk);
> -		if (priv->aclk)
> -			clk_disable_unprepare(priv->aclk);
> +		pm_runtime_put_sync(&priv->pdev->dev);
>  	}
>  	dev_dbg(&priv->pdev->dev, "%s: n_active_ch %d\n", __func__,
>  		atomic_read(&priv->n_active_ch));
> @@ -325,14 +345,111 @@ static int stm32_dfsdm_probe(struct platform_device *pdev)
>  
>  	platform_set_drvdata(pdev, dfsdm);
>  
> -	return devm_of_platform_populate(&pdev->dev);
> +	ret = stm32_dfsdm_clk_prepare_enable(dfsdm);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Failed to start clock\n");
> +		return ret;
> +	}
> +
> +	pm_runtime_get_noresume(&pdev->dev);
> +	pm_runtime_set_active(&pdev->dev);
> +	pm_runtime_enable(&pdev->dev);
> +
> +	ret = of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
> +	if (ret)
> +		goto pm_put;
> +
> +	pm_runtime_put(&pdev->dev);
> +
> +	return 0;
> +
> +pm_put:
> +	pm_runtime_disable(&pdev->dev);
> +	pm_runtime_set_suspended(&pdev->dev);
> +	pm_runtime_put_noidle(&pdev->dev);
> +	stm32_dfsdm_clk_disable_unprepare(dfsdm);
> +
> +	return ret;
> +}
> +
> +static int stm32_dfsdm_core_remove(struct platform_device *pdev)
> +{
> +	struct stm32_dfsdm *dfsdm = platform_get_drvdata(pdev);
> +
> +	pm_runtime_get_sync(&pdev->dev);
> +	of_platform_depopulate(&pdev->dev);
> +	pm_runtime_disable(&pdev->dev);
> +	pm_runtime_set_suspended(&pdev->dev);
> +	pm_runtime_put_noidle(&pdev->dev);
> +	stm32_dfsdm_clk_disable_unprepare(dfsdm);
> +
> +	return 0;
> +}
> +
> +static int __maybe_unused stm32_dfsdm_core_suspend(struct device *dev)
> +{
> +	struct stm32_dfsdm *dfsdm = dev_get_drvdata(dev);
> +	struct dfsdm_priv *priv = to_stm32_dfsdm_priv(dfsdm);
> +	int ret;
> +
> +	ret = pm_runtime_force_suspend(dev);
> +	if (ret)
> +		return ret;
> +
> +	/* Balance devm_regmap_init_mmio_clk() clk_prepare() */
> +	clk_unprepare(priv->clk);
> +
> +	return pinctrl_pm_select_sleep_state(dev);
> +}
> +
> +static int __maybe_unused stm32_dfsdm_core_resume(struct device *dev)
> +{
> +	struct stm32_dfsdm *dfsdm = dev_get_drvdata(dev);
> +	struct dfsdm_priv *priv = to_stm32_dfsdm_priv(dfsdm);
> +	int ret;
> +
> +	ret = pinctrl_pm_select_default_state(dev);
> +	if (ret)
> +		return ret;
> +
> +	ret = clk_prepare(priv->clk);
> +	if (ret)
> +		return ret;
> +
> +	return pm_runtime_force_resume(dev);
>  }
>  
> +static int __maybe_unused stm32_dfsdm_core_runtime_suspend(struct device *dev)
> +{
> +	struct stm32_dfsdm *dfsdm = dev_get_drvdata(dev);
> +
> +	stm32_dfsdm_clk_disable_unprepare(dfsdm);
> +
> +	return 0;
> +}
> +
> +static int __maybe_unused stm32_dfsdm_core_runtime_resume(struct device *dev)
> +{
> +	struct stm32_dfsdm *dfsdm = dev_get_drvdata(dev);
> +
> +	return stm32_dfsdm_clk_prepare_enable(dfsdm);
> +}
> +
> +static const struct dev_pm_ops stm32_dfsdm_core_pm_ops = {
> +	SET_SYSTEM_SLEEP_PM_OPS(stm32_dfsdm_core_suspend,
> +				stm32_dfsdm_core_resume)
> +	SET_RUNTIME_PM_OPS(stm32_dfsdm_core_runtime_suspend,
> +			   stm32_dfsdm_core_runtime_resume,
> +			   NULL)
> +};
> +
>  static struct platform_driver stm32_dfsdm_driver = {
>  	.probe = stm32_dfsdm_probe,
> +	.remove = stm32_dfsdm_core_remove,
>  	.driver = {
>  		.name = "stm32-dfsdm",
>  		.of_match_table = stm32_dfsdm_of_match,
> +		.pm = &stm32_dfsdm_core_pm_ops,
>  	},
>  };
>
diff mbox series

Patch

diff --git a/drivers/iio/adc/stm32-dfsdm-adc.c b/drivers/iio/adc/stm32-dfsdm-adc.c
index 531ca7e..a599097 100644
--- a/drivers/iio/adc/stm32-dfsdm-adc.c
+++ b/drivers/iio/adc/stm32-dfsdm-adc.c
@@ -851,24 +851,18 @@  static int stm32_dfsdm_update_scan_mode(struct iio_dev *indio_dev,
 	return 0;
 }
 
-static int stm32_dfsdm_postenable(struct iio_dev *indio_dev)
+static int __stm32_dfsdm_postenable(struct iio_dev *indio_dev)
 {
 	struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
 	int ret;
 
-	if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED) {
-		ret = iio_triggered_buffer_postenable(indio_dev);
-		if (ret < 0)
-			return ret;
-	}
-
 	/* Reset adc buffer index */
 	adc->bufi = 0;
 
 	if (adc->hwc) {
 		ret = iio_hw_consumer_enable(adc->hwc);
 		if (ret < 0)
-			goto err_predisable;
+			return ret;
 	}
 
 	ret = stm32_dfsdm_start_dfsdm(adc->dfsdm);
@@ -896,6 +890,26 @@  static int stm32_dfsdm_postenable(struct iio_dev *indio_dev)
 err_stop_hwc:
 	if (adc->hwc)
 		iio_hw_consumer_disable(adc->hwc);
+
+	return ret;
+}
+
+static int stm32_dfsdm_postenable(struct iio_dev *indio_dev)
+{
+	int ret;
+
+	if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED) {
+		ret = iio_triggered_buffer_postenable(indio_dev);
+		if (ret < 0)
+			return ret;
+	}
+
+	ret = __stm32_dfsdm_postenable(indio_dev);
+	if (ret < 0)
+		goto err_predisable;
+
+	return 0;
+
 err_predisable:
 	if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED)
 		iio_triggered_buffer_predisable(indio_dev);
@@ -903,7 +917,7 @@  static int stm32_dfsdm_postenable(struct iio_dev *indio_dev)
 	return ret;
 }
 
-static int stm32_dfsdm_predisable(struct iio_dev *indio_dev)
+static void __stm32_dfsdm_predisable(struct iio_dev *indio_dev)
 {
 	struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
 
@@ -915,6 +929,11 @@  static int stm32_dfsdm_predisable(struct iio_dev *indio_dev)
 
 	if (adc->hwc)
 		iio_hw_consumer_disable(adc->hwc);
+}
+
+static int stm32_dfsdm_predisable(struct iio_dev *indio_dev)
+{
+	__stm32_dfsdm_predisable(indio_dev);
 
 	if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED)
 		iio_triggered_buffer_predisable(indio_dev);
@@ -1492,10 +1511,48 @@  static int stm32_dfsdm_adc_remove(struct platform_device *pdev)
 	return 0;
 }
 
+static int __maybe_unused stm32_dfsdm_adc_suspend(struct device *dev)
+{
+	struct stm32_dfsdm_adc *adc = dev_get_drvdata(dev);
+	struct iio_dev *indio_dev = iio_priv_to_dev(adc);
+
+	if (iio_buffer_enabled(indio_dev))
+		__stm32_dfsdm_predisable(indio_dev);
+
+	return 0;
+}
+
+static int __maybe_unused stm32_dfsdm_adc_resume(struct device *dev)
+{
+	struct stm32_dfsdm_adc *adc = dev_get_drvdata(dev);
+	struct iio_dev *indio_dev = iio_priv_to_dev(adc);
+	const struct iio_chan_spec *chan;
+	struct stm32_dfsdm_channel *ch;
+	int i, ret;
+
+	/* restore channels configuration */
+	for (i = 0; i < indio_dev->num_channels; i++) {
+		chan = indio_dev->channels + i;
+		ch = &adc->dfsdm->ch_list[chan->channel];
+		ret = stm32_dfsdm_chan_configure(adc->dfsdm, ch);
+		if (ret)
+			return ret;
+	}
+
+	if (iio_buffer_enabled(indio_dev))
+		__stm32_dfsdm_postenable(indio_dev);
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(stm32_dfsdm_adc_pm_ops,
+			 stm32_dfsdm_adc_suspend, stm32_dfsdm_adc_resume);
+
 static struct platform_driver stm32_dfsdm_adc_driver = {
 	.driver = {
 		.name = "stm32-dfsdm-adc",
 		.of_match_table = stm32_dfsdm_adc_match,
+		.pm = &stm32_dfsdm_adc_pm_ops,
 	},
 	.probe = stm32_dfsdm_adc_probe,
 	.remove = stm32_dfsdm_adc_remove,
diff --git a/drivers/iio/adc/stm32-dfsdm-core.c b/drivers/iio/adc/stm32-dfsdm-core.c
index 472b809..0a4d374 100644
--- a/drivers/iio/adc/stm32-dfsdm-core.c
+++ b/drivers/iio/adc/stm32-dfsdm-core.c
@@ -12,6 +12,8 @@ 
 #include <linux/interrupt.h>
 #include <linux/module.h>
 #include <linux/of_device.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/pm_runtime.h>
 #include <linux/regmap.h>
 #include <linux/slab.h>
 
@@ -90,6 +92,36 @@  struct dfsdm_priv {
 	struct clk *aclk; /* audio clock */
 };
 
+static inline struct dfsdm_priv *to_stm32_dfsdm_priv(struct stm32_dfsdm *dfsdm)
+{
+	return container_of(dfsdm, struct dfsdm_priv, dfsdm);
+}
+
+static int stm32_dfsdm_clk_prepare_enable(struct stm32_dfsdm *dfsdm)
+{
+	struct dfsdm_priv *priv = to_stm32_dfsdm_priv(dfsdm);
+	int ret;
+
+	ret = clk_prepare_enable(priv->clk);
+	if (ret || !priv->aclk)
+		return ret;
+
+	ret = clk_prepare_enable(priv->aclk);
+	if (ret)
+		clk_disable_unprepare(priv->clk);
+
+	return ret;
+}
+
+static void stm32_dfsdm_clk_disable_unprepare(struct stm32_dfsdm *dfsdm)
+{
+	struct dfsdm_priv *priv = to_stm32_dfsdm_priv(dfsdm);
+
+	if (priv->aclk)
+		clk_disable_unprepare(priv->aclk);
+	clk_disable_unprepare(priv->clk);
+}
+
 /**
  * stm32_dfsdm_start_dfsdm - start global dfsdm interface.
  *
@@ -98,24 +130,17 @@  struct dfsdm_priv {
  */
 int stm32_dfsdm_start_dfsdm(struct stm32_dfsdm *dfsdm)
 {
-	struct dfsdm_priv *priv = container_of(dfsdm, struct dfsdm_priv, dfsdm);
+	struct dfsdm_priv *priv = to_stm32_dfsdm_priv(dfsdm);
 	struct device *dev = &priv->pdev->dev;
 	unsigned int clk_div = priv->spi_clk_out_div, clk_src;
 	int ret;
 
 	if (atomic_inc_return(&priv->n_active_ch) == 1) {
-		ret = clk_prepare_enable(priv->clk);
+		ret = pm_runtime_get_sync(dev);
 		if (ret < 0) {
-			dev_err(dev, "Failed to start clock\n");
+			pm_runtime_put_noidle(dev);
 			goto error_ret;
 		}
-		if (priv->aclk) {
-			ret = clk_prepare_enable(priv->aclk);
-			if (ret < 0) {
-				dev_err(dev, "Failed to start audio clock\n");
-				goto disable_clk;
-			}
-		}
 
 		/* select clock source, e.g. 0 for "dfsdm" or 1 for "audio" */
 		clk_src = priv->aclk ? 1 : 0;
@@ -123,21 +148,21 @@  int stm32_dfsdm_start_dfsdm(struct stm32_dfsdm *dfsdm)
 					 DFSDM_CHCFGR1_CKOUTSRC_MASK,
 					 DFSDM_CHCFGR1_CKOUTSRC(clk_src));
 		if (ret < 0)
-			goto disable_aclk;
+			goto pm_put;
 
 		/* Output the SPI CLKOUT (if clk_div == 0 clock if OFF) */
 		ret = regmap_update_bits(dfsdm->regmap, DFSDM_CHCFGR1(0),
 					 DFSDM_CHCFGR1_CKOUTDIV_MASK,
 					 DFSDM_CHCFGR1_CKOUTDIV(clk_div));
 		if (ret < 0)
-			goto disable_aclk;
+			goto pm_put;
 
 		/* Global enable of DFSDM interface */
 		ret = regmap_update_bits(dfsdm->regmap, DFSDM_CHCFGR1(0),
 					 DFSDM_CHCFGR1_DFSDMEN_MASK,
 					 DFSDM_CHCFGR1_DFSDMEN(1));
 		if (ret < 0)
-			goto disable_aclk;
+			goto pm_put;
 	}
 
 	dev_dbg(dev, "%s: n_active_ch %d\n", __func__,
@@ -145,11 +170,8 @@  int stm32_dfsdm_start_dfsdm(struct stm32_dfsdm *dfsdm)
 
 	return 0;
 
-disable_aclk:
-	clk_disable_unprepare(priv->aclk);
-disable_clk:
-	clk_disable_unprepare(priv->clk);
-
+pm_put:
+	pm_runtime_put_sync(dev);
 error_ret:
 	atomic_dec(&priv->n_active_ch);
 
@@ -165,7 +187,7 @@  EXPORT_SYMBOL_GPL(stm32_dfsdm_start_dfsdm);
  */
 int stm32_dfsdm_stop_dfsdm(struct stm32_dfsdm *dfsdm)
 {
-	struct dfsdm_priv *priv = container_of(dfsdm, struct dfsdm_priv, dfsdm);
+	struct dfsdm_priv *priv = to_stm32_dfsdm_priv(dfsdm);
 	int ret;
 
 	if (atomic_dec_and_test(&priv->n_active_ch)) {
@@ -183,9 +205,7 @@  int stm32_dfsdm_stop_dfsdm(struct stm32_dfsdm *dfsdm)
 		if (ret < 0)
 			return ret;
 
-		clk_disable_unprepare(priv->clk);
-		if (priv->aclk)
-			clk_disable_unprepare(priv->aclk);
+		pm_runtime_put_sync(&priv->pdev->dev);
 	}
 	dev_dbg(&priv->pdev->dev, "%s: n_active_ch %d\n", __func__,
 		atomic_read(&priv->n_active_ch));
@@ -325,14 +345,111 @@  static int stm32_dfsdm_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, dfsdm);
 
-	return devm_of_platform_populate(&pdev->dev);
+	ret = stm32_dfsdm_clk_prepare_enable(dfsdm);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to start clock\n");
+		return ret;
+	}
+
+	pm_runtime_get_noresume(&pdev->dev);
+	pm_runtime_set_active(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
+
+	ret = of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
+	if (ret)
+		goto pm_put;
+
+	pm_runtime_put(&pdev->dev);
+
+	return 0;
+
+pm_put:
+	pm_runtime_disable(&pdev->dev);
+	pm_runtime_set_suspended(&pdev->dev);
+	pm_runtime_put_noidle(&pdev->dev);
+	stm32_dfsdm_clk_disable_unprepare(dfsdm);
+
+	return ret;
+}
+
+static int stm32_dfsdm_core_remove(struct platform_device *pdev)
+{
+	struct stm32_dfsdm *dfsdm = platform_get_drvdata(pdev);
+
+	pm_runtime_get_sync(&pdev->dev);
+	of_platform_depopulate(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+	pm_runtime_set_suspended(&pdev->dev);
+	pm_runtime_put_noidle(&pdev->dev);
+	stm32_dfsdm_clk_disable_unprepare(dfsdm);
+
+	return 0;
+}
+
+static int __maybe_unused stm32_dfsdm_core_suspend(struct device *dev)
+{
+	struct stm32_dfsdm *dfsdm = dev_get_drvdata(dev);
+	struct dfsdm_priv *priv = to_stm32_dfsdm_priv(dfsdm);
+	int ret;
+
+	ret = pm_runtime_force_suspend(dev);
+	if (ret)
+		return ret;
+
+	/* Balance devm_regmap_init_mmio_clk() clk_prepare() */
+	clk_unprepare(priv->clk);
+
+	return pinctrl_pm_select_sleep_state(dev);
+}
+
+static int __maybe_unused stm32_dfsdm_core_resume(struct device *dev)
+{
+	struct stm32_dfsdm *dfsdm = dev_get_drvdata(dev);
+	struct dfsdm_priv *priv = to_stm32_dfsdm_priv(dfsdm);
+	int ret;
+
+	ret = pinctrl_pm_select_default_state(dev);
+	if (ret)
+		return ret;
+
+	ret = clk_prepare(priv->clk);
+	if (ret)
+		return ret;
+
+	return pm_runtime_force_resume(dev);
 }
 
+static int __maybe_unused stm32_dfsdm_core_runtime_suspend(struct device *dev)
+{
+	struct stm32_dfsdm *dfsdm = dev_get_drvdata(dev);
+
+	stm32_dfsdm_clk_disable_unprepare(dfsdm);
+
+	return 0;
+}
+
+static int __maybe_unused stm32_dfsdm_core_runtime_resume(struct device *dev)
+{
+	struct stm32_dfsdm *dfsdm = dev_get_drvdata(dev);
+
+	return stm32_dfsdm_clk_prepare_enable(dfsdm);
+}
+
+static const struct dev_pm_ops stm32_dfsdm_core_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(stm32_dfsdm_core_suspend,
+				stm32_dfsdm_core_resume)
+	SET_RUNTIME_PM_OPS(stm32_dfsdm_core_runtime_suspend,
+			   stm32_dfsdm_core_runtime_resume,
+			   NULL)
+};
+
 static struct platform_driver stm32_dfsdm_driver = {
 	.probe = stm32_dfsdm_probe,
+	.remove = stm32_dfsdm_core_remove,
 	.driver = {
 		.name = "stm32-dfsdm",
 		.of_match_table = stm32_dfsdm_of_match,
+		.pm = &stm32_dfsdm_core_pm_ops,
 	},
 };