iio: imu: inv_mpu6050: use runtime pm with autosuspend

Use runtime power management for handling chip power and
sensor engines on/off. Simplifies things a lot since pm
runtime already has reference counter.
Usage of autosuspend reduces the number of power on/off. This
makes polling interface now usable to get data at low
frequency.

Signed-off-by: Jean-Baptiste Maneyrol <jmaneyrol@invensense.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
index 9076b6b..56e5731 100644 (file)
--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
@@ -16,6 +16,8 @@
 #include <linux/acpi.h>
 #include <linux/platform_device.h>
 #include <linux/regulator/consumer.h>
+#include <linux/pm.h>
+#include <linux/pm_runtime.h>
 #include "inv_mpu_iio.h"
 #include "inv_mpu_magn.h"
 
@@ -396,30 +398,18 @@ int inv_mpu6050_switch_engine(struct inv_mpu6050_state *st, bool en,
        return 0;
 }
 
-int inv_mpu6050_set_power_itg(struct inv_mpu6050_state *st, bool power_on)
+static int inv_mpu6050_set_power_itg(struct inv_mpu6050_state *st,
+                                    bool power_on)
 {
        int result;
 
-       if (power_on) {
-               if (!st->powerup_count) {
-                       result = inv_mpu6050_pwr_mgmt_1_write(st, false, -1, -1);
-                       if (result)
-                               return result;
-                       usleep_range(INV_MPU6050_REG_UP_TIME_MIN,
-                                    INV_MPU6050_REG_UP_TIME_MAX);
-               }
-               st->powerup_count++;
-       } else {
-               if (st->powerup_count == 1) {
-                       result = inv_mpu6050_pwr_mgmt_1_write(st, true, -1, -1);
-                       if (result)
-                               return result;
-               }
-               st->powerup_count--;
-       }
+       result = inv_mpu6050_pwr_mgmt_1_write(st, !power_on, -1, -1);
+       if (result)
+               return result;
 
-       dev_dbg(regmap_get_device(st->map), "set power %d, count=%u\n",
-               power_on, st->powerup_count);
+       if (power_on)
+               usleep_range(INV_MPU6050_REG_UP_TIME_MIN,
+                            INV_MPU6050_REG_UP_TIME_MAX);
 
        return 0;
 }
@@ -563,6 +553,7 @@ static int inv_mpu6050_read_channel_data(struct iio_dev *indio_dev,
                                         int *val)
 {
        struct inv_mpu6050_state *st = iio_priv(indio_dev);
+       struct device *pdev = regmap_get_device(st->map);
        unsigned int freq_hz, period_us, min_sleep_us, max_sleep_us;
        int result;
        int ret;
@@ -571,92 +562,85 @@ static int inv_mpu6050_read_channel_data(struct iio_dev *indio_dev,
        freq_hz = INV_MPU6050_DIVIDER_TO_FIFO_RATE(st->chip_config.divider);
        period_us = 1000000 / freq_hz;
 
-       result = inv_mpu6050_set_power_itg(st, true);
-       if (result)
+       result = pm_runtime_get_sync(pdev);
+       if (result < 0) {
+               pm_runtime_put_noidle(pdev);
                return result;
+       }
 
        switch (chan->type) {
        case IIO_ANGL_VEL:
-               result = inv_mpu6050_switch_engine(st, true,
-                               INV_MPU6050_SENSOR_GYRO);
-               if (result)
-                       goto error_power_off;
-               /* need to wait 2 periods to have first valid sample */
-               min_sleep_us = 2 * period_us;
-               max_sleep_us = 2 * (period_us + period_us / 2);
-               usleep_range(min_sleep_us, max_sleep_us);
+               if (!st->chip_config.gyro_en) {
+                       result = inv_mpu6050_switch_engine(st, true,
+                                       INV_MPU6050_SENSOR_GYRO);
+                       if (result)
+                               goto error_power_off;
+                       /* need to wait 2 periods to have first valid sample */
+                       min_sleep_us = 2 * period_us;
+                       max_sleep_us = 2 * (period_us + period_us / 2);
+                       usleep_range(min_sleep_us, max_sleep_us);
+               }
                ret = inv_mpu6050_sensor_show(st, st->reg->raw_gyro,
                                              chan->channel2, val);
-               result = inv_mpu6050_switch_engine(st, false,
-                               INV_MPU6050_SENSOR_GYRO);
-               if (result)
-                       goto error_power_off;
                break;
        case IIO_ACCEL:
-               result = inv_mpu6050_switch_engine(st, true,
-                               INV_MPU6050_SENSOR_ACCL);
-               if (result)
-                       goto error_power_off;
-               /* wait 1 period for first sample availability */
-               min_sleep_us = period_us;
-               max_sleep_us = period_us + period_us / 2;
-               usleep_range(min_sleep_us, max_sleep_us);
+               if (!st->chip_config.accl_en) {
+                       result = inv_mpu6050_switch_engine(st, true,
+                                       INV_MPU6050_SENSOR_ACCL);
+                       if (result)
+                               goto error_power_off;
+                       /* wait 1 period for first sample availability */
+                       min_sleep_us = period_us;
+                       max_sleep_us = period_us + period_us / 2;
+                       usleep_range(min_sleep_us, max_sleep_us);
+               }
                ret = inv_mpu6050_sensor_show(st, st->reg->raw_accl,
                                              chan->channel2, val);
-               result = inv_mpu6050_switch_engine(st, false,
-                               INV_MPU6050_SENSOR_ACCL);
-               if (result)
-                       goto error_power_off;
                break;
        case IIO_TEMP:
-               result = inv_mpu6050_switch_engine(st, true,
-                               INV_MPU6050_SENSOR_TEMP);
-               if (result)
-                       goto error_power_off;
-               /* wait 1 period for first sample availability */
-               min_sleep_us = period_us;
-               max_sleep_us = period_us + period_us / 2;
-               usleep_range(min_sleep_us, max_sleep_us);
+               if (!st->chip_config.temp_en) {
+                       result = inv_mpu6050_switch_engine(st, true,
+                                       INV_MPU6050_SENSOR_TEMP);
+                       if (result)
+                               goto error_power_off;
+                       /* wait 1 period for first sample availability */
+                       min_sleep_us = period_us;
+                       max_sleep_us = period_us + period_us / 2;
+                       usleep_range(min_sleep_us, max_sleep_us);
+               }
                ret = inv_mpu6050_sensor_show(st, st->reg->temperature,
                                              IIO_MOD_X, val);
-               result = inv_mpu6050_switch_engine(st, false,
-                               INV_MPU6050_SENSOR_TEMP);
-               if (result)
-                       goto error_power_off;
                break;
        case IIO_MAGN:
-               result = inv_mpu6050_switch_engine(st, true,
-                               INV_MPU6050_SENSOR_MAGN);
-               if (result)
-                       goto error_power_off;
-               /* frequency is limited for magnetometer */
-               if (freq_hz > INV_MPU_MAGN_FREQ_HZ_MAX) {
-                       freq_hz = INV_MPU_MAGN_FREQ_HZ_MAX;
-                       period_us = 1000000 / freq_hz;
+               if (!st->chip_config.magn_en) {
+                       result = inv_mpu6050_switch_engine(st, true,
+                                       INV_MPU6050_SENSOR_MAGN);
+                       if (result)
+                               goto error_power_off;
+                       /* frequency is limited for magnetometer */
+                       if (freq_hz > INV_MPU_MAGN_FREQ_HZ_MAX) {
+                               freq_hz = INV_MPU_MAGN_FREQ_HZ_MAX;
+                               period_us = 1000000 / freq_hz;
+                       }
+                       /* need to wait 2 periods to have first valid sample */
+                       min_sleep_us = 2 * period_us;
+                       max_sleep_us = 2 * (period_us + period_us / 2);
+                       usleep_range(min_sleep_us, max_sleep_us);
                }
-               /* need to wait 2 periods to have first valid sample */
-               min_sleep_us = 2 * period_us;
-               max_sleep_us = 2 * (period_us + period_us / 2);
-               usleep_range(min_sleep_us, max_sleep_us);
                ret = inv_mpu_magn_read(st, chan->channel2, val);
-               result = inv_mpu6050_switch_engine(st, false,
-                               INV_MPU6050_SENSOR_MAGN);
-               if (result)
-                       goto error_power_off;
                break;
        default:
                ret = -EINVAL;
                break;
        }
 
-       result = inv_mpu6050_set_power_itg(st, false);
-       if (result)
-               goto error_power_off;
+       pm_runtime_mark_last_busy(pdev);
+       pm_runtime_put_autosuspend(pdev);
 
        return ret;
 
 error_power_off:
-       inv_mpu6050_set_power_itg(st, false);
+       pm_runtime_put_autosuspend(pdev);
        return result;
 }
 
@@ -795,6 +779,7 @@ static int inv_mpu6050_write_raw(struct iio_dev *indio_dev,
                                 int val, int val2, long mask)
 {
        struct inv_mpu6050_state  *st = iio_priv(indio_dev);
+       struct device *pdev = regmap_get_device(st->map);
        int result;
 
        /*
@@ -806,9 +791,11 @@ static int inv_mpu6050_write_raw(struct iio_dev *indio_dev,
                return result;
 
        mutex_lock(&st->lock);
-       result = inv_mpu6050_set_power_itg(st, true);
-       if (result)
+       result = pm_runtime_get_sync(pdev);
+       if (result < 0) {
+               pm_runtime_put_noidle(pdev);
                goto error_write_raw_unlock;
+       }
 
        switch (mask) {
        case IIO_CHAN_INFO_SCALE:
@@ -846,7 +833,8 @@ static int inv_mpu6050_write_raw(struct iio_dev *indio_dev,
                break;
        }
 
-       result |= inv_mpu6050_set_power_itg(st, false);
+       pm_runtime_mark_last_busy(pdev);
+       pm_runtime_put_autosuspend(pdev);
 error_write_raw_unlock:
        mutex_unlock(&st->lock);
        iio_device_release_direct_mode(indio_dev);
@@ -903,6 +891,7 @@ inv_mpu6050_fifo_rate_store(struct device *dev, struct device_attribute *attr,
        int result;
        struct iio_dev *indio_dev = dev_to_iio_dev(dev);
        struct inv_mpu6050_state *st = iio_priv(indio_dev);
+       struct device *pdev = regmap_get_device(st->map);
 
        if (kstrtoint(buf, 10, &fifo_rate))
                return -EINVAL;
@@ -920,9 +909,11 @@ inv_mpu6050_fifo_rate_store(struct device *dev, struct device_attribute *attr,
                result = 0;
                goto fifo_rate_fail_unlock;
        }
-       result = inv_mpu6050_set_power_itg(st, true);
-       if (result)
+       result = pm_runtime_get_sync(pdev);
+       if (result < 0) {
+               pm_runtime_put_noidle(pdev);
                goto fifo_rate_fail_unlock;
+       }
 
        result = regmap_write(st->map, st->reg->sample_rate_div, d);
        if (result)
@@ -938,8 +929,9 @@ inv_mpu6050_fifo_rate_store(struct device *dev, struct device_attribute *attr,
        if (result)
                goto fifo_rate_fail_power_off;
 
+       pm_runtime_mark_last_busy(pdev);
 fifo_rate_fail_power_off:
-       result |= inv_mpu6050_set_power_itg(st, false);
+       pm_runtime_put_autosuspend(pdev);
 fifo_rate_fail_unlock:
        mutex_unlock(&st->lock);
        if (result)
@@ -1385,6 +1377,14 @@ static void inv_mpu_core_disable_regulator_action(void *_data)
        inv_mpu_core_disable_regulator_vddio(st);
 }
 
+static void inv_mpu_pm_disable(void *data)
+{
+       struct device *dev = data;
+
+       pm_runtime_put_sync_suspend(dev);
+       pm_runtime_disable(dev);
+}
+
 int inv_mpu_core_probe(struct regmap *regmap, int irq, const char *name,
                int (*inv_mpu_bus_setup)(struct iio_dev *), int chip_type)
 {
@@ -1409,7 +1409,6 @@ int inv_mpu_core_probe(struct regmap *regmap, int irq, const char *name,
        st = iio_priv(indio_dev);
        mutex_init(&st->lock);
        st->chip_type = chip_type;
-       st->powerup_count = 0;
        st->irq = irq;
        st->map = regmap;
 
@@ -1521,8 +1520,16 @@ int inv_mpu_core_probe(struct regmap *regmap, int irq, const char *name,
                        goto error_power_off;
        }
 
-       /* chip init is done, turning off */
-       result = inv_mpu6050_set_power_itg(st, false);
+       /* chip init is done, turning on runtime power management */
+       result = pm_runtime_set_active(dev);
+       if (result)
+               goto error_power_off;
+       pm_runtime_get_noresume(dev);
+       pm_runtime_enable(dev);
+       pm_runtime_set_autosuspend_delay(dev, INV_MPU6050_SUSPEND_DELAY_MS);
+       pm_runtime_use_autosuspend(dev);
+       pm_runtime_put(dev);
+       result = devm_add_action_or_reset(dev, inv_mpu_pm_disable, dev);
        if (result)
                return result;
 
@@ -1590,11 +1597,10 @@ error_power_off:
 }
 EXPORT_SYMBOL_GPL(inv_mpu_core_probe);
 
-#ifdef CONFIG_PM_SLEEP
-
-static int inv_mpu_resume(struct device *dev)
+static int __maybe_unused inv_mpu_resume(struct device *dev)
 {
-       struct inv_mpu6050_state *st = iio_priv(dev_get_drvdata(dev));
+       struct iio_dev *indio_dev = dev_get_drvdata(dev);
+       struct inv_mpu6050_state *st = iio_priv(indio_dev);
        int result;
 
        mutex_lock(&st->lock);
@@ -1603,27 +1609,101 @@ static int inv_mpu_resume(struct device *dev)
                goto out_unlock;
 
        result = inv_mpu6050_set_power_itg(st, true);
+       if (result)
+               goto out_unlock;
+
+       result = inv_mpu6050_switch_engine(st, true, st->suspended_sensors);
+       if (result)
+               goto out_unlock;
+
+       if (iio_buffer_enabled(indio_dev))
+               result = inv_mpu6050_prepare_fifo(st, true);
+
 out_unlock:
        mutex_unlock(&st->lock);
 
        return result;
 }
 
-static int inv_mpu_suspend(struct device *dev)
+static int __maybe_unused inv_mpu_suspend(struct device *dev)
 {
-       struct inv_mpu6050_state *st = iio_priv(dev_get_drvdata(dev));
+       struct iio_dev *indio_dev = dev_get_drvdata(dev);
+       struct inv_mpu6050_state *st = iio_priv(indio_dev);
        int result;
 
        mutex_lock(&st->lock);
+
+       if (iio_buffer_enabled(indio_dev)) {
+               result = inv_mpu6050_prepare_fifo(st, false);
+               if (result)
+                       goto out_unlock;
+       }
+
+       st->suspended_sensors = 0;
+       if (st->chip_config.accl_en)
+               st->suspended_sensors |= INV_MPU6050_SENSOR_ACCL;
+       if (st->chip_config.gyro_en)
+               st->suspended_sensors |= INV_MPU6050_SENSOR_GYRO;
+       if (st->chip_config.temp_en)
+               st->suspended_sensors |= INV_MPU6050_SENSOR_TEMP;
+       if (st->chip_config.magn_en)
+               st->suspended_sensors |= INV_MPU6050_SENSOR_MAGN;
+       result = inv_mpu6050_switch_engine(st, false, st->suspended_sensors);
+       if (result)
+               goto out_unlock;
+
        result = inv_mpu6050_set_power_itg(st, false);
+       if (result)
+               goto out_unlock;
+
        inv_mpu_core_disable_regulator_vddio(st);
+out_unlock:
        mutex_unlock(&st->lock);
 
        return result;
 }
-#endif /* CONFIG_PM_SLEEP */
 
-SIMPLE_DEV_PM_OPS(inv_mpu_pmops, inv_mpu_suspend, inv_mpu_resume);
+static int __maybe_unused inv_mpu_runtime_suspend(struct device *dev)
+{
+       struct inv_mpu6050_state *st = iio_priv(dev_get_drvdata(dev));
+       unsigned int sensors;
+       int ret;
+
+       mutex_lock(&st->lock);
+
+       sensors = INV_MPU6050_SENSOR_ACCL | INV_MPU6050_SENSOR_GYRO |
+                       INV_MPU6050_SENSOR_TEMP | INV_MPU6050_SENSOR_MAGN;
+       ret = inv_mpu6050_switch_engine(st, false, sensors);
+       if (ret)
+               goto out_unlock;
+
+       ret = inv_mpu6050_set_power_itg(st, false);
+       if (ret)
+               goto out_unlock;
+
+       inv_mpu_core_disable_regulator_vddio(st);
+
+out_unlock:
+       mutex_unlock(&st->lock);
+       return ret;
+}
+
+static int __maybe_unused inv_mpu_runtime_resume(struct device *dev)
+{
+       struct inv_mpu6050_state *st = iio_priv(dev_get_drvdata(dev));
+       int ret;
+
+       ret = inv_mpu_core_enable_regulator_vddio(st);
+       if (ret)
+               return ret;
+
+       return inv_mpu6050_set_power_itg(st, true);
+}
+
+const struct dev_pm_ops inv_mpu_pmops = {
+       SET_SYSTEM_SLEEP_PM_OPS(inv_mpu_suspend, inv_mpu_resume)
+       SET_RUNTIME_PM_OPS(inv_mpu_runtime_suspend, inv_mpu_runtime_resume, NULL)
+};
 EXPORT_SYMBOL_GPL(inv_mpu_pmops);
 
 MODULE_AUTHOR("Invensense Corporation");

diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h b/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h
index e328c98..cd38b3f 100644 (file)
--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h
+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h
@@ -164,6 +164,7 @@ struct inv_mpu6050_hw {
  *  @magn_disabled:     magnetometer disabled for backward compatibility reason.
  *  @magn_raw_to_gauss:        coefficient to convert mag raw value to Gauss.
  *  @magn_orient:       magnetometer sensor chip orientation if available.
+ *  @suspended_sensors:        sensors mask of sensors turned off for suspend
  */
 struct inv_mpu6050_state {
        struct mutex lock;
@@ -174,7 +175,6 @@ struct inv_mpu6050_state {
        enum   inv_devices chip_type;
        struct i2c_mux_core *muxc;
        struct i2c_client *mux_client;
-       unsigned int powerup_count;
        struct inv_mpu6050_platform_data plat_data;
        struct iio_mount_matrix orientation;
        struct regmap *map;
@@ -189,6 +189,7 @@ struct inv_mpu6050_state {
        bool magn_disabled;
        s32 magn_raw_to_gauss[3];
        struct iio_mount_matrix magn_orient;
+       unsigned int suspended_sensors;
 };
 
 /*register and associated bit definition*/
@@ -312,6 +313,7 @@ struct inv_mpu6050_state {
 #define INV_MPU6050_ACCEL_UP_TIME            20
 #define INV_MPU6050_GYRO_UP_TIME             35
 #define INV_MPU6050_GYRO_DOWN_TIME           150
+#define INV_MPU6050_SUSPEND_DELAY_MS         2000
 
 /* delay time in microseconds */
 #define INV_MPU6050_REG_UP_TIME_MIN          5000
@@ -439,7 +441,6 @@ int inv_mpu6050_prepare_fifo(struct inv_mpu6050_state *st, bool enable);
 int inv_mpu6050_switch_engine(struct inv_mpu6050_state *st, bool en,
                              unsigned int mask);
 int inv_mpu6050_write_reg(struct inv_mpu6050_state *st, int reg, u8 val);
-int inv_mpu6050_set_power_itg(struct inv_mpu6050_state *st, bool power_on);
 int inv_mpu_acpi_create_mux_client(struct i2c_client *client);
 void inv_mpu_acpi_delete_mux_client(struct i2c_client *client);
 int inv_mpu_core_probe(struct regmap *regmap, int irq, const char *name,

diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_trigger.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_trigger.c
index f53f50d..f7b5a70 100644 (file)
--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_trigger.c
+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_trigger.c
@@ -3,6 +3,7 @@
 * Copyright (C) 2012 Invensense, Inc.
 */
 
+#include <linux/pm_runtime.h>
 #include "inv_mpu_iio.h"
 
 static unsigned int inv_scan_query_mpu6050(struct iio_dev *indio_dev)
@@ -156,41 +157,43 @@ int inv_mpu6050_prepare_fifo(struct inv_mpu6050_state *st, bool enable)
 static int inv_mpu6050_set_enable(struct iio_dev *indio_dev, bool enable)
 {
        struct inv_mpu6050_state *st = iio_priv(indio_dev);
+       struct device *pdev = regmap_get_device(st->map);
        unsigned int scan;
        int result;
 
-       scan = inv_scan_query(indio_dev);
-
        if (enable) {
-               result = inv_mpu6050_set_power_itg(st, true);
-               if (result)
+               scan = inv_scan_query(indio_dev);
+               result = pm_runtime_get_sync(pdev);
+               if (result < 0) {
+                       pm_runtime_put_noidle(pdev);
                        return result;
+               }
+               /*
+                * In case autosuspend didn't trigger, turn off first not
+                * required sensors.
+                */
+               result = inv_mpu6050_switch_engine(st, false, ~scan);
+               if (result)
+                       goto error_power_off;
                result = inv_mpu6050_switch_engine(st, true, scan);
                if (result)
                        goto error_power_off;
                st->skip_samples = inv_compute_skip_samples(st);
                result = inv_mpu6050_prepare_fifo(st, true);
                if (result)
-                       goto error_sensors_off;
+                       goto error_power_off;
        } else {
                result = inv_mpu6050_prepare_fifo(st, false);
                if (result)
-                       goto error_sensors_off;
-               result = inv_mpu6050_switch_engine(st, false, scan);
-               if (result)
-                       goto error_power_off;
-
-               result = inv_mpu6050_set_power_itg(st, false);
-               if (result)
                        goto error_power_off;
+               pm_runtime_mark_last_busy(pdev);
+               pm_runtime_put_autosuspend(pdev);
        }
 
        return 0;
 
-error_sensors_off:
-       inv_mpu6050_switch_engine(st, false, scan);
 error_power_off:
-       inv_mpu6050_set_power_itg(st, false);
+       pm_runtime_put_autosuspend(pdev);
        return result;
 }