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@xxxxxx>
---
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,
},
};
--
2.7.4
