diff options
Diffstat (limited to 'drivers/iio/dac/stm32-dac.c')
| -rw-r--r-- | drivers/iio/dac/stm32-dac.c | 94 |
1 files changed, 92 insertions, 2 deletions
diff --git a/drivers/iio/dac/stm32-dac.c b/drivers/iio/dac/stm32-dac.c index cce26a3a6627..f22c1d9129b2 100644 --- a/drivers/iio/dac/stm32-dac.c +++ b/drivers/iio/dac/stm32-dac.c @@ -13,6 +13,7 @@ #include <linux/kernel.h> #include <linux/module.h> #include <linux/platform_device.h> +#include <linux/pm_runtime.h> #include "stm32-dac-core.h" @@ -20,6 +21,8 @@ #define STM32_DAC_CHANNEL_2 2 #define STM32_DAC_IS_CHAN_1(ch) ((ch) & STM32_DAC_CHANNEL_1) +#define STM32_DAC_AUTO_SUSPEND_DELAY_MS 2000 + /** * struct stm32_dac - private data of DAC driver * @common: reference to DAC common data @@ -49,15 +52,34 @@ static int stm32_dac_set_enable_state(struct iio_dev *indio_dev, int ch, bool enable) { struct stm32_dac *dac = iio_priv(indio_dev); + struct device *dev = indio_dev->dev.parent; u32 msk = STM32_DAC_IS_CHAN_1(ch) ? STM32_DAC_CR_EN1 : STM32_DAC_CR_EN2; u32 en = enable ? msk : 0; int ret; + /* already enabled / disabled ? */ + mutex_lock(&indio_dev->mlock); + ret = stm32_dac_is_enabled(indio_dev, ch); + if (ret < 0 || enable == !!ret) { + mutex_unlock(&indio_dev->mlock); + return ret < 0 ? ret : 0; + } + + if (enable) { + ret = pm_runtime_get_sync(dev); + if (ret < 0) { + pm_runtime_put_noidle(dev); + mutex_unlock(&indio_dev->mlock); + return ret; + } + } + ret = regmap_update_bits(dac->common->regmap, STM32_DAC_CR, msk, en); + mutex_unlock(&indio_dev->mlock); if (ret < 0) { dev_err(&indio_dev->dev, "%s failed\n", en ? "Enable" : "Disable"); - return ret; + goto err_put_pm; } /* @@ -68,7 +90,20 @@ static int stm32_dac_set_enable_state(struct iio_dev *indio_dev, int ch, if (en && dac->common->hfsel) udelay(1); + if (!enable) { + pm_runtime_mark_last_busy(dev); + pm_runtime_put_autosuspend(dev); + } + return 0; + +err_put_pm: + if (enable) { + pm_runtime_mark_last_busy(dev); + pm_runtime_put_autosuspend(dev); + } + + return ret; } static int stm32_dac_get_value(struct stm32_dac *dac, int channel, int *val) @@ -272,6 +307,7 @@ static int stm32_dac_chan_of_init(struct iio_dev *indio_dev) static int stm32_dac_probe(struct platform_device *pdev) { struct device_node *np = pdev->dev.of_node; + struct device *dev = &pdev->dev; struct iio_dev *indio_dev; struct stm32_dac *dac; int ret; @@ -296,9 +332,61 @@ static int stm32_dac_probe(struct platform_device *pdev) if (ret < 0) return ret; - return devm_iio_device_register(&pdev->dev, indio_dev); + /* Get stm32-dac-core PM online */ + pm_runtime_get_noresume(dev); + pm_runtime_set_active(dev); + pm_runtime_set_autosuspend_delay(dev, STM32_DAC_AUTO_SUSPEND_DELAY_MS); + pm_runtime_use_autosuspend(dev); + pm_runtime_enable(dev); + + ret = iio_device_register(indio_dev); + if (ret) + goto err_pm_put; + + pm_runtime_mark_last_busy(dev); + pm_runtime_put_autosuspend(dev); + + return 0; + +err_pm_put: + pm_runtime_disable(dev); + pm_runtime_set_suspended(dev); + pm_runtime_put_noidle(dev); + + return ret; } +static int stm32_dac_remove(struct platform_device *pdev) +{ + struct iio_dev *indio_dev = platform_get_drvdata(pdev); + + pm_runtime_get_sync(&pdev->dev); + iio_device_unregister(indio_dev); + pm_runtime_disable(&pdev->dev); + pm_runtime_set_suspended(&pdev->dev); + pm_runtime_put_noidle(&pdev->dev); + + return 0; +} + +static int __maybe_unused stm32_dac_suspend(struct device *dev) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + int channel = indio_dev->channels[0].channel; + int ret; + + /* Ensure DAC is disabled before suspend */ + ret = stm32_dac_is_enabled(indio_dev, channel); + if (ret) + return ret < 0 ? ret : -EBUSY; + + return pm_runtime_force_suspend(dev); +} + +static const struct dev_pm_ops stm32_dac_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(stm32_dac_suspend, pm_runtime_force_resume) +}; + static const struct of_device_id stm32_dac_of_match[] = { { .compatible = "st,stm32-dac", }, {}, @@ -307,9 +395,11 @@ MODULE_DEVICE_TABLE(of, stm32_dac_of_match); static struct platform_driver stm32_dac_driver = { .probe = stm32_dac_probe, + .remove = stm32_dac_remove, .driver = { .name = "stm32-dac", .of_match_table = stm32_dac_of_match, + .pm = &stm32_dac_pm_ops, }, }; module_platform_driver(stm32_dac_driver); |