From 6ec417d2f1a028705a1ae6f59d3e15344f6a4fbe Mon Sep 17 00:00:00 2001 From: Fabrice Gasnier Date: Mon, 25 Mar 2019 15:49:28 +0100 Subject: [PATCH] iio: adc: stm32-dfsdm: add PM support 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 Signed-off-by: Jonathan Cameron --- 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 051561c1357a..19adc2b23472 100644 --- a/drivers/iio/adc/stm32-dfsdm-adc.c +++ b/drivers/iio/adc/stm32-dfsdm-adc.c @@ -868,24 +868,18 @@ 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); @@ -913,6 +907,26 @@ stop_dfsdm: 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); @@ -920,7 +934,7 @@ err_predisable: 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); @@ -932,6 +946,11 @@ 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); @@ -1496,10 +1515,48 @@ 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 472b809ebf94..0a4d3746d21c 100644 --- a/drivers/iio/adc/stm32-dfsdm-core.c +++ b/drivers/iio/adc/stm32-dfsdm-core.c @@ -12,6 +12,8 @@ #include #include #include +#include +#include #include #include @@ -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, }, }; -- 2.11.0