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 <fabrice.gasnier@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
Fabrice Gasnier 2018-11-20 11:12:31 +01:00 committed by Jonathan Cameron
parent 0da98c7b28
commit 9bdbb1139c
2 changed files with 258 additions and 93 deletions

View File

@ -16,6 +16,7 @@
#include <linux/irqdomain.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/pm_runtime.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
@ -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 @@ static int stm32h7_adc_clk_sel(struct platform_device *pdev,
/* 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);

View File

@ -22,6 +22,7 @@
#include <linux/iopoll.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/of.h>
#include <linux/of_device.h>
@ -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 @@ static int stm32_adc_buffer_postenable(struct iio_dev *indio_dev)
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 @@ static int stm32_adc_buffer_postenable(struct iio_dev *indio_dev)
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 @@ static int stm32_adc_probe(struct platform_device *pdev)
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);