From 9bdbb1139ca11301257fa1fae9cf71a598911efc Mon Sep 17 00:00:00 2001 From: Fabrice Gasnier Date: Tue, 20 Nov 2018 11:12:31 +0100 Subject: [PATCH] iio: adc: stm32-adc: add power management support Add support for runtime PM & sleep. Move all regulator and clock management to dedicated HW start/stop routines. Then rely on (runtime) PM OPS to call them. Signed-off-by: Fabrice Gasnier Signed-off-by: Jonathan Cameron --- drivers/iio/adc/stm32-adc-core.c | 182 +++++++++++++++++++++---------- drivers/iio/adc/stm32-adc.c | 169 +++++++++++++++++++++------- 2 files changed, 258 insertions(+), 93 deletions(-) diff --git a/drivers/iio/adc/stm32-adc-core.c b/drivers/iio/adc/stm32-adc-core.c index ca432e7b6ff1..2327ec18b40c 100644 --- a/drivers/iio/adc/stm32-adc-core.c +++ b/drivers/iio/adc/stm32-adc-core.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include @@ -48,15 +49,19 @@ #define STM32H7_CKMODE_SHIFT 16 #define STM32H7_CKMODE_MASK GENMASK(17, 16) +#define STM32_ADC_CORE_SLEEP_DELAY_MS 2000 + /** * stm32_adc_common_regs - stm32 common registers, compatible dependent data * @csr: common status register offset + * @ccr: common control register offset * @eoc1: adc1 end of conversion flag in @csr * @eoc2: adc2 end of conversion flag in @csr * @eoc3: adc3 end of conversion flag in @csr */ struct stm32_adc_common_regs { u32 csr; + u32 ccr; u32 eoc1_msk; u32 eoc2_msk; u32 eoc3_msk; @@ -85,6 +90,7 @@ struct stm32_adc_priv_cfg { * @vref: regulator reference * @cfg: compatible configuration data * @common: common data for all ADC instances + * @ccr_bak: backup CCR in low power mode */ struct stm32_adc_priv { int irq[STM32_ADC_MAX_ADCS]; @@ -94,6 +100,7 @@ struct stm32_adc_priv { struct regulator *vref; const struct stm32_adc_priv_cfg *cfg; struct stm32_adc_common common; + u32 ccr_bak; }; static struct stm32_adc_priv *to_stm32_adc_priv(struct stm32_adc_common *com) @@ -265,6 +272,7 @@ out: /* STM32F4 common registers definitions */ static const struct stm32_adc_common_regs stm32f4_adc_common_regs = { .csr = STM32F4_ADC_CSR, + .ccr = STM32F4_ADC_CCR, .eoc1_msk = STM32F4_EOC1, .eoc2_msk = STM32F4_EOC2, .eoc3_msk = STM32F4_EOC3, @@ -273,6 +281,7 @@ static const struct stm32_adc_common_regs stm32f4_adc_common_regs = { /* STM32H7 common registers definitions */ static const struct stm32_adc_common_regs stm32h7_adc_common_regs = { .csr = STM32H7_ADC_CSR, + .ccr = STM32H7_ADC_CCR, .eoc1_msk = STM32H7_EOC_MST, .eoc2_msk = STM32H7_EOC_SLV, }; @@ -379,6 +388,61 @@ static void stm32_adc_irq_remove(struct platform_device *pdev, } } +static int stm32_adc_core_hw_start(struct device *dev) +{ + struct stm32_adc_common *common = dev_get_drvdata(dev); + struct stm32_adc_priv *priv = to_stm32_adc_priv(common); + int ret; + + ret = regulator_enable(priv->vref); + if (ret < 0) { + dev_err(dev, "vref enable failed\n"); + return ret; + } + + if (priv->bclk) { + ret = clk_prepare_enable(priv->bclk); + if (ret < 0) { + dev_err(dev, "bus clk enable failed\n"); + goto err_regulator_disable; + } + } + + if (priv->aclk) { + ret = clk_prepare_enable(priv->aclk); + if (ret < 0) { + dev_err(dev, "adc clk enable failed\n"); + goto err_bclk_disable; + } + } + + writel_relaxed(priv->ccr_bak, priv->common.base + priv->cfg->regs->ccr); + + return 0; + +err_bclk_disable: + if (priv->bclk) + clk_disable_unprepare(priv->bclk); +err_regulator_disable: + regulator_disable(priv->vref); + + return ret; +} + +static void stm32_adc_core_hw_stop(struct device *dev) +{ + struct stm32_adc_common *common = dev_get_drvdata(dev); + struct stm32_adc_priv *priv = to_stm32_adc_priv(common); + + /* Backup CCR that may be lost (depends on power state to achieve) */ + priv->ccr_bak = readl_relaxed(priv->common.base + priv->cfg->regs->ccr); + if (priv->aclk) + clk_disable_unprepare(priv->aclk); + if (priv->bclk) + clk_disable_unprepare(priv->bclk); + regulator_disable(priv->vref); +} + static int stm32_adc_probe(struct platform_device *pdev) { struct stm32_adc_priv *priv; @@ -393,6 +457,7 @@ static int stm32_adc_probe(struct platform_device *pdev) priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; + platform_set_drvdata(pdev, &priv->common); priv->cfg = (const struct stm32_adc_priv_cfg *) of_match_device(dev->driver->of_match_table, dev)->data; @@ -410,67 +475,51 @@ static int stm32_adc_probe(struct platform_device *pdev) return ret; } - ret = regulator_enable(priv->vref); - if (ret < 0) { - dev_err(&pdev->dev, "vref enable failed\n"); - return ret; - } - - ret = regulator_get_voltage(priv->vref); - if (ret < 0) { - dev_err(&pdev->dev, "vref get voltage failed, %d\n", ret); - goto err_regulator_disable; - } - priv->common.vref_mv = ret / 1000; - dev_dbg(&pdev->dev, "vref+=%dmV\n", priv->common.vref_mv); - priv->aclk = devm_clk_get(&pdev->dev, "adc"); if (IS_ERR(priv->aclk)) { ret = PTR_ERR(priv->aclk); - if (ret == -ENOENT) { - priv->aclk = NULL; - } else { + if (ret != -ENOENT) { dev_err(&pdev->dev, "Can't get 'adc' clock\n"); - goto err_regulator_disable; - } - } - - if (priv->aclk) { - ret = clk_prepare_enable(priv->aclk); - if (ret < 0) { - dev_err(&pdev->dev, "adc clk enable failed\n"); - goto err_regulator_disable; + return ret; } + priv->aclk = NULL; } priv->bclk = devm_clk_get(&pdev->dev, "bus"); if (IS_ERR(priv->bclk)) { ret = PTR_ERR(priv->bclk); - if (ret == -ENOENT) { - priv->bclk = NULL; - } else { + if (ret != -ENOENT) { dev_err(&pdev->dev, "Can't get 'bus' clock\n"); - goto err_aclk_disable; + return ret; } + priv->bclk = NULL; } - if (priv->bclk) { - ret = clk_prepare_enable(priv->bclk); - if (ret < 0) { - dev_err(&pdev->dev, "adc clk enable failed\n"); - goto err_aclk_disable; - } + pm_runtime_get_noresume(dev); + pm_runtime_set_active(dev); + pm_runtime_set_autosuspend_delay(dev, STM32_ADC_CORE_SLEEP_DELAY_MS); + pm_runtime_use_autosuspend(dev); + pm_runtime_enable(dev); + + ret = stm32_adc_core_hw_start(dev); + if (ret) + goto err_pm_stop; + + ret = regulator_get_voltage(priv->vref); + if (ret < 0) { + dev_err(&pdev->dev, "vref get voltage failed, %d\n", ret); + goto err_hw_stop; } + priv->common.vref_mv = ret / 1000; + dev_dbg(&pdev->dev, "vref+=%dmV\n", priv->common.vref_mv); ret = priv->cfg->clk_sel(pdev, priv); if (ret < 0) - goto err_bclk_disable; + goto err_hw_stop; ret = stm32_adc_irq_probe(pdev, priv); if (ret < 0) - goto err_bclk_disable; - - platform_set_drvdata(pdev, &priv->common); + goto err_hw_stop; ret = of_platform_populate(np, NULL, NULL, &pdev->dev); if (ret < 0) { @@ -478,21 +527,19 @@ static int stm32_adc_probe(struct platform_device *pdev) goto err_irq_remove; } + pm_runtime_mark_last_busy(dev); + pm_runtime_put_autosuspend(dev); + return 0; err_irq_remove: stm32_adc_irq_remove(pdev, priv); - -err_bclk_disable: - if (priv->bclk) - clk_disable_unprepare(priv->bclk); - -err_aclk_disable: - if (priv->aclk) - clk_disable_unprepare(priv->aclk); - -err_regulator_disable: - regulator_disable(priv->vref); +err_hw_stop: + stm32_adc_core_hw_stop(dev); +err_pm_stop: + pm_runtime_disable(dev); + pm_runtime_set_suspended(dev); + pm_runtime_put_noidle(dev); return ret; } @@ -502,17 +549,39 @@ static int stm32_adc_remove(struct platform_device *pdev) struct stm32_adc_common *common = platform_get_drvdata(pdev); struct stm32_adc_priv *priv = to_stm32_adc_priv(common); + pm_runtime_get_sync(&pdev->dev); of_platform_depopulate(&pdev->dev); stm32_adc_irq_remove(pdev, priv); - if (priv->bclk) - clk_disable_unprepare(priv->bclk); - if (priv->aclk) - clk_disable_unprepare(priv->aclk); - regulator_disable(priv->vref); + stm32_adc_core_hw_stop(&pdev->dev); + pm_runtime_disable(&pdev->dev); + pm_runtime_set_suspended(&pdev->dev); + pm_runtime_put_noidle(&pdev->dev); return 0; } +#if defined(CONFIG_PM) +static int stm32_adc_core_runtime_suspend(struct device *dev) +{ + stm32_adc_core_hw_stop(dev); + + return 0; +} + +static int stm32_adc_core_runtime_resume(struct device *dev) +{ + return stm32_adc_core_hw_start(dev); +} +#endif + +static const struct dev_pm_ops stm32_adc_core_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, + pm_runtime_force_resume) + SET_RUNTIME_PM_OPS(stm32_adc_core_runtime_suspend, + stm32_adc_core_runtime_resume, + NULL) +}; + static const struct stm32_adc_priv_cfg stm32f4_adc_priv_cfg = { .regs = &stm32f4_adc_common_regs, .clk_sel = stm32f4_adc_clk_sel, @@ -552,6 +621,7 @@ static struct platform_driver stm32_adc_driver = { .driver = { .name = "stm32-adc-core", .of_match_table = stm32_adc_of_match, + .pm = &stm32_adc_core_pm_ops, }, }; module_platform_driver(stm32_adc_driver); diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c index 7980c46fe37c..1ba800b91273 100644 --- a/drivers/iio/adc/stm32-adc.c +++ b/drivers/iio/adc/stm32-adc.c @@ -22,6 +22,7 @@ #include #include #include +#include #include #include @@ -148,6 +149,7 @@ enum stm32h7_adc_dmngt { #define STM32_ADC_MAX_SMP 7 /* SMPx range is [0..7] */ #define STM32_ADC_TIMEOUT_US 100000 #define STM32_ADC_TIMEOUT (msecs_to_jiffies(STM32_ADC_TIMEOUT_US / 1000)) +#define STM32_ADC_HW_STOP_DELAY_MS 100 #define STM32_DMA_BUFFER_SIZE PAGE_SIZE @@ -623,6 +625,47 @@ static void stm32_adc_set_res(struct stm32_adc *adc) stm32_adc_writel(adc, res->reg, val); } +static int stm32_adc_hw_stop(struct device *dev) +{ + struct stm32_adc *adc = dev_get_drvdata(dev); + + if (adc->cfg->unprepare) + adc->cfg->unprepare(adc); + + if (adc->clk) + clk_disable_unprepare(adc->clk); + + return 0; +} + +static int stm32_adc_hw_start(struct device *dev) +{ + struct stm32_adc *adc = dev_get_drvdata(dev); + int ret; + + if (adc->clk) { + ret = clk_prepare_enable(adc->clk); + if (ret) + return ret; + } + + stm32_adc_set_res(adc); + + if (adc->cfg->prepare) { + ret = adc->cfg->prepare(adc); + if (ret) + goto err_clk_dis; + } + + return 0; + +err_clk_dis: + if (adc->clk) + clk_disable_unprepare(adc->clk); + + return ret; +} + /** * stm32f4_adc_start_conv() - Start conversions for regular channels. * @adc: stm32 adc instance @@ -1171,6 +1214,7 @@ static int stm32_adc_single_conv(struct iio_dev *indio_dev, int *res) { struct stm32_adc *adc = iio_priv(indio_dev); + struct device *dev = indio_dev->dev.parent; const struct stm32_adc_regspec *regs = adc->cfg->regs; long timeout; u32 val; @@ -1180,10 +1224,10 @@ static int stm32_adc_single_conv(struct iio_dev *indio_dev, adc->bufi = 0; - if (adc->cfg->prepare) { - ret = adc->cfg->prepare(adc); - if (ret) - return ret; + ret = pm_runtime_get_sync(dev); + if (ret < 0) { + pm_runtime_put_noidle(dev); + return ret; } /* Apply sampling time settings */ @@ -1221,8 +1265,8 @@ static int stm32_adc_single_conv(struct iio_dev *indio_dev, stm32_adc_conv_irq_disable(adc); - if (adc->cfg->unprepare) - adc->cfg->unprepare(adc); + pm_runtime_mark_last_busy(dev); + pm_runtime_put_autosuspend(dev); return ret; } @@ -1330,15 +1374,22 @@ static int stm32_adc_update_scan_mode(struct iio_dev *indio_dev, const unsigned long *scan_mask) { struct stm32_adc *adc = iio_priv(indio_dev); + struct device *dev = indio_dev->dev.parent; int ret; + ret = pm_runtime_get_sync(dev); + if (ret < 0) { + pm_runtime_put_noidle(dev); + return ret; + } + adc->num_conv = bitmap_weight(scan_mask, indio_dev->masklength); ret = stm32_adc_conf_scan_seq(indio_dev, scan_mask); - if (ret) - return ret; + pm_runtime_mark_last_busy(dev); + pm_runtime_put_autosuspend(dev); - return 0; + return ret; } static int stm32_adc_of_xlate(struct iio_dev *indio_dev, @@ -1368,12 +1419,23 @@ static int stm32_adc_debugfs_reg_access(struct iio_dev *indio_dev, unsigned *readval) { struct stm32_adc *adc = iio_priv(indio_dev); + struct device *dev = indio_dev->dev.parent; + int ret; + + ret = pm_runtime_get_sync(dev); + if (ret < 0) { + pm_runtime_put_noidle(dev); + return ret; + } if (!readval) stm32_adc_writel(adc, reg, writeval); else *readval = stm32_adc_readl(adc, reg); + pm_runtime_mark_last_busy(dev); + pm_runtime_put_autosuspend(dev); + return 0; } @@ -1459,18 +1521,19 @@ static int stm32_adc_dma_start(struct iio_dev *indio_dev) static int stm32_adc_buffer_postenable(struct iio_dev *indio_dev) { struct stm32_adc *adc = iio_priv(indio_dev); + struct device *dev = indio_dev->dev.parent; int ret; - if (adc->cfg->prepare) { - ret = adc->cfg->prepare(adc); - if (ret) - return ret; + ret = pm_runtime_get_sync(dev); + if (ret < 0) { + pm_runtime_put_noidle(dev); + return ret; } ret = stm32_adc_set_trig(indio_dev, indio_dev->trig); if (ret) { dev_err(&indio_dev->dev, "Can't set trigger\n"); - goto err_unprepare; + goto err_pm_put; } ret = stm32_adc_dma_start(indio_dev); @@ -1498,9 +1561,9 @@ err_stop_dma: dmaengine_terminate_all(adc->dma_chan); err_clr_trig: stm32_adc_set_trig(indio_dev, NULL); -err_unprepare: - if (adc->cfg->unprepare) - adc->cfg->unprepare(adc); +err_pm_put: + pm_runtime_mark_last_busy(dev); + pm_runtime_put_autosuspend(dev); return ret; } @@ -1508,6 +1571,7 @@ err_unprepare: static int stm32_adc_buffer_predisable(struct iio_dev *indio_dev) { struct stm32_adc *adc = iio_priv(indio_dev); + struct device *dev = indio_dev->dev.parent; int ret; adc->cfg->stop_conv(adc); @@ -1524,8 +1588,8 @@ static int stm32_adc_buffer_predisable(struct iio_dev *indio_dev) if (stm32_adc_set_trig(indio_dev, NULL)) dev_err(&indio_dev->dev, "Can't clear trigger\n"); - if (adc->cfg->unprepare) - adc->cfg->unprepare(adc); + pm_runtime_mark_last_busy(dev); + pm_runtime_put_autosuspend(dev); return ret; } @@ -1864,26 +1928,17 @@ static int stm32_adc_probe(struct platform_device *pdev) } } - if (adc->clk) { - ret = clk_prepare_enable(adc->clk); - if (ret < 0) { - dev_err(&pdev->dev, "clk enable failed\n"); - return ret; - } - } - ret = stm32_adc_of_get_resolution(indio_dev); if (ret < 0) - goto err_clk_disable; - stm32_adc_set_res(adc); + return ret; ret = stm32_adc_chan_of_init(indio_dev); if (ret < 0) - goto err_clk_disable; + return ret; ret = stm32_adc_dma_request(indio_dev); if (ret < 0) - goto err_clk_disable; + return ret; ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time, @@ -1894,15 +1949,35 @@ static int stm32_adc_probe(struct platform_device *pdev) goto err_dma_disable; } + /* Get stm32-adc-core PM online */ + pm_runtime_get_noresume(dev); + pm_runtime_set_active(dev); + pm_runtime_set_autosuspend_delay(dev, STM32_ADC_HW_STOP_DELAY_MS); + pm_runtime_use_autosuspend(dev); + pm_runtime_enable(dev); + + ret = stm32_adc_hw_start(dev); + if (ret) + goto err_buffer_cleanup; + ret = iio_device_register(indio_dev); if (ret) { dev_err(&pdev->dev, "iio dev register failed\n"); - goto err_buffer_cleanup; + goto err_hw_stop; } + pm_runtime_mark_last_busy(dev); + pm_runtime_put_autosuspend(dev); + return 0; +err_hw_stop: + stm32_adc_hw_stop(dev); + err_buffer_cleanup: + pm_runtime_disable(dev); + pm_runtime_set_suspended(dev); + pm_runtime_put_noidle(dev); iio_triggered_buffer_cleanup(indio_dev); err_dma_disable: @@ -1912,9 +1987,6 @@ err_dma_disable: adc->rx_buf, adc->rx_dma_buf); dma_release_channel(adc->dma_chan); } -err_clk_disable: - if (adc->clk) - clk_disable_unprepare(adc->clk); return ret; } @@ -1924,7 +1996,12 @@ static int stm32_adc_remove(struct platform_device *pdev) struct stm32_adc *adc = platform_get_drvdata(pdev); struct iio_dev *indio_dev = iio_priv_to_dev(adc); + pm_runtime_get_sync(&pdev->dev); iio_device_unregister(indio_dev); + stm32_adc_hw_stop(&pdev->dev); + pm_runtime_disable(&pdev->dev); + pm_runtime_set_suspended(&pdev->dev); + pm_runtime_put_noidle(&pdev->dev); iio_triggered_buffer_cleanup(indio_dev); if (adc->dma_chan) { dma_free_coherent(adc->dma_chan->device->dev, @@ -1932,12 +2009,29 @@ static int stm32_adc_remove(struct platform_device *pdev) adc->rx_buf, adc->rx_dma_buf); dma_release_channel(adc->dma_chan); } - if (adc->clk) - clk_disable_unprepare(adc->clk); return 0; } +#if defined(CONFIG_PM) +static int stm32_adc_runtime_suspend(struct device *dev) +{ + return stm32_adc_hw_stop(dev); +} + +static int stm32_adc_runtime_resume(struct device *dev) +{ + return stm32_adc_hw_start(dev); +} +#endif + +static const struct dev_pm_ops stm32_adc_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, + pm_runtime_force_resume) + SET_RUNTIME_PM_OPS(stm32_adc_runtime_suspend, stm32_adc_runtime_resume, + NULL) +}; + static const struct stm32_adc_cfg stm32f4_adc_cfg = { .regs = &stm32f4_adc_regspec, .adc_info = &stm32f4_adc_info, @@ -1985,6 +2079,7 @@ static struct platform_driver stm32_adc_driver = { .driver = { .name = "stm32-adc", .of_match_table = stm32_adc_of_match, + .pm = &stm32_adc_pm_ops, }, }; module_platform_driver(stm32_adc_driver); -- 2.30.2