diff mbox series

[v3,1/1] iio: bmi323: peripheral in lowest power state on suspend

Message ID 20240824141122.334620-2-benato.denis96@gmail.com (mailing list archive)
State Accepted
Headers show
Series iio: bmi323: have the peripheral consume less power | expand

Commit Message

Denis Benato Aug. 24, 2024, 2:11 p.m. UTC 
The bmi323 is mounted on some devices that are powered
by an internal battery: help in reducing system overall power drain
while the system is in s2idle or the imu driver is not loaded
by resetting it in its lowest power draining state.

Signed-off-by: Denis Benato <benato.denis96@gmail.com>
---
 drivers/iio/imu/bmi323/bmi323_core.c | 155 ++++++++++++++++++++++++++-
 1 file changed, 153 insertions(+), 2 deletions(-)

Comments

Jonathan Cameron Aug. 26, 2024, 10:23 a.m. UTC | #1 
On Sat, 24 Aug 2024 16:11:22 +0200
Denis Benato <benato.denis96@gmail.com> wrote:

> The bmi323 is mounted on some devices that are powered
> by an internal battery: help in reducing system overall power drain
> while the system is in s2idle or the imu driver is not loaded
> by resetting it in its lowest power draining state.
> 
> Signed-off-by: Denis Benato <benato.denis96@gmail.com>
Applied with some whitespace tweaks.

> ---
>  drivers/iio/imu/bmi323/bmi323_core.c | 155 ++++++++++++++++++++++++++-
>  1 file changed, 153 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/iio/imu/bmi323/bmi323_core.c b/drivers/iio/imu/bmi323/bmi323_core.c
> index 4b2b211a3e88..57be22c97cb9 100644
> --- a/drivers/iio/imu/bmi323/bmi323_core.c
> +++ b/drivers/iio/imu/bmi323/bmi323_core.c
> @@ -118,6 +118,38 @@ static const struct bmi323_hw bmi323_hw[2] = {
>  	},
>  };
>  
> +static const unsigned int bmi323_reg_savestate[] = {
> +	BMI323_INT_MAP1_REG,
> +	BMI323_INT_MAP2_REG,
> +	BMI323_IO_INT_CTR_REG,
> +	BMI323_IO_INT_CONF_REG,
> +	BMI323_ACC_CONF_REG,
> +	BMI323_GYRO_CONF_REG,
> +	BMI323_FEAT_IO0_REG,
> +	BMI323_FIFO_WTRMRK_REG,
> +	BMI323_FIFO_CONF_REG
> +};
> +
> +static const unsigned int bmi323_ext_reg_savestate[] = {
> +	BMI323_GEN_SET1_REG,
> +	BMI323_TAP1_REG,
> +	BMI323_TAP2_REG,
> +	BMI323_TAP3_REG,
> +	BMI323_FEAT_IO0_S_TAP_MSK,
> +	BMI323_STEP_SC1_REG,
> +	BMI323_ANYMO1_REG,
> +	BMI323_NOMO1_REG,
> +	BMI323_ANYMO1_REG + BMI323_MO2_OFFSET,
> +	BMI323_NOMO1_REG + BMI323_MO2_OFFSET,
> +	BMI323_ANYMO1_REG + BMI323_MO3_OFFSET,
> +	BMI323_NOMO1_REG + BMI323_MO3_OFFSET
> +};
> +
> +struct bmi323_regs_runtime_pm {
> +	unsigned int reg_settings[ARRAY_SIZE(bmi323_reg_savestate)];
> +	unsigned int ext_reg_settings[ARRAY_SIZE(bmi323_ext_reg_savestate)];
> +};
> +
>  struct bmi323_data {
>  	struct device *dev;
>  	struct regmap *regmap;
> @@ -130,6 +162,7 @@ struct bmi323_data {
>  	u32 odrns[BMI323_SENSORS_CNT];
>  	u32 odrhz[BMI323_SENSORS_CNT];
>  	unsigned int feature_events;
> +	struct bmi323_regs_runtime_pm runtime_pm_status;
>  
>  	/*
>  	 * Lock to protect the members of device's private data from concurrent
> @@ -1972,6 +2005,11 @@ static void bmi323_disable(void *data_ptr)
>  
>  	bmi323_set_mode(data, BMI323_ACCEL, ACC_GYRO_MODE_DISABLE);
>  	bmi323_set_mode(data, BMI323_GYRO, ACC_GYRO_MODE_DISABLE);
> +
> +	/*
> +	 * Place the peripheral in its lowest power consuming state.
> +	 */
> +	regmap_write(data->regmap, BMI323_CMD_REG, BMI323_RST_VAL);
>  }
>  
>  static int bmi323_set_bw(struct bmi323_data *data,
> @@ -2030,6 +2068,13 @@ static int bmi323_init(struct bmi323_data *data)
>  		return dev_err_probe(data->dev, -EINVAL,
>  				     "Sensor power error = 0x%x\n", val);
>  
> +	return 0;
> +}
> +
> +static int bmi323_init_reset(struct bmi323_data *data)
> +{
> +	int ret;
> +
>  	/*
>  	 * Set the Bandwidth coefficient which defines the 3 dB cutoff
>  	 * frequency in relation to the ODR.
> @@ -2078,12 +2123,18 @@ int bmi323_core_probe(struct device *dev)
>  	data = iio_priv(indio_dev);
>  	data->dev = dev;
>  	data->regmap = regmap;
> +	data->irq_pin = BMI323_IRQ_DISABLED;
> +	data->state = BMI323_IDLE;
>  	mutex_init(&data->mutex);
>  
>  	ret = bmi323_init(data);
>  	if (ret)
>  		return -EINVAL;
>  
> +	ret = bmi323_init_reset(data);
> +	if (ret)
> +		return -EINVAL;
> +
>  	if (!iio_read_acpi_mount_matrix(dev, &data->orientation, "ROTM")) {
>  		ret = iio_read_mount_matrix(dev, &data->orientation);
>  		if (ret)
> @@ -2117,7 +2168,7 @@ int bmi323_core_probe(struct device *dev)
>  		return dev_err_probe(data->dev, ret,
>  				     "Unable to register iio device\n");
>  
> -	return 0;
> +	return bmi323_fifo_disable(data);
>  }
>  EXPORT_SYMBOL_NS_GPL(bmi323_core_probe, IIO_BMI323);
>  
> @@ -2125,13 +2176,113 @@ EXPORT_SYMBOL_NS_GPL(bmi323_core_probe, IIO_BMI323);
>  static int bmi323_core_runtime_suspend(struct device *dev)
>  {
>  	struct iio_dev *indio_dev = dev_get_drvdata(dev);
> +	struct bmi323_data *data = iio_priv(indio_dev);
> +	struct bmi323_regs_runtime_pm *savestate = &data->runtime_pm_status;
> +	int ret;
> +
> +	guard(mutex)(&data->mutex);
> +
> +	ret = iio_device_suspend_triggering(indio_dev);
> +	if (ret)
> +		return ret;
> +
> +	/* Save registers meant to be restored by resume pm callback. */
> +	for (unsigned int i = 0; i < ARRAY_SIZE(bmi323_reg_savestate); i++) {
> +		ret = regmap_read(data->regmap, bmi323_reg_savestate[i],
> +			   &savestate->reg_settings[i]);
> +		if (ret) {
> +			dev_err(data->dev, "Error reading bmi323 reg 0x%x: %d\n",
> +				  bmi323_reg_savestate[i], ret);
> +			return ret;
> +		}
> +	}
> +
> +	for (unsigned int i = 0; i < ARRAY_SIZE(bmi323_ext_reg_savestate); i++) {
> +		ret = bmi323_read_ext_reg(data, bmi323_reg_savestate[i],
> +			   &savestate->reg_settings[i]);
> +		if (ret) {
> +			dev_err(data->dev, "Error reading bmi323 external reg 0x%x: %d\n",
> +				  bmi323_reg_savestate[i], ret);
> +			return ret;
> +		}
> +	}
> +
> +	/* Perform soft reset to place the device in its lowest power state. */
> +	ret = regmap_write(data->regmap, BMI323_CMD_REG, BMI323_RST_VAL);
> +	if (ret)
> +		return ret;
>  
> -	return iio_device_suspend_triggering(indio_dev);
> +	return 0;
>  }
>  
>  static int bmi323_core_runtime_resume(struct device *dev)
>  {
>  	struct iio_dev *indio_dev = dev_get_drvdata(dev);
> +	struct bmi323_data *data = iio_priv(indio_dev);
> +	struct bmi323_regs_runtime_pm *savestate = &data->runtime_pm_status;
> +	unsigned int val;
> +	int ret;
> +
> +	guard(mutex)(&data->mutex);
> +
> +	/*
> +	 * Perform the device power-on and initial setup once again
> +	 * after being reset in the lower power state by runtime-pm.
> +	 */
> +	ret = bmi323_init(data);
> +	if (!ret)
> +		return ret;
> +
> +	/* Register must be cleared before changing an active config */
> +	ret = regmap_write(data->regmap, BMI323_FEAT_IO0_REG, 0);
> +	if (ret) {
> +		dev_err(data->dev, "Error stopping feature engine\n");
> +		return ret;
> +	}
> +
> +	for (unsigned int i = 0; i < ARRAY_SIZE(bmi323_ext_reg_savestate); i++) {
> +		ret = bmi323_write_ext_reg(data, bmi323_reg_savestate[i],
> +			  savestate->reg_settings[i]);
> +		if (ret) {
> +			dev_err(data->dev, "Error writing bmi323 external reg 0x%x: %d\n",
> +				  bmi323_reg_savestate[i], ret);
> +			return ret;
> +		}
> +	}
> +
> +	for (unsigned int i = 0; i < ARRAY_SIZE(bmi323_reg_savestate); i++) {
> +		ret = regmap_write(data->regmap, bmi323_reg_savestate[i],
> +			  savestate->reg_settings[i]);
> +		if (ret) {
> +			dev_err(data->dev, "Error writing bmi323 reg 0x%x: %d\n",
> +				  bmi323_reg_savestate[i], ret);
> +			return ret;
> +		}
> +	}
> +
> +	/*
> +	 * Clear old FIFO samples that might be generated before suspend
> +	 * or generated from a peripheral state not equal to the saved one.
> +	 */
> +	if (data->state == BMI323_BUFFER_FIFO) {
> +		ret = regmap_write(data->regmap, BMI323_FIFO_CTRL_REG,
> +			   BMI323_FIFO_FLUSH_MSK);
> +		if (ret) {
> +			dev_err(data->dev, "Error flushing FIFO buffer: %d\n", ret);
> +			return ret;
> +		}
> +	}
> +
> +	ret = regmap_read(data->regmap, BMI323_ERR_REG, &val);
> +	if (ret) {
> +		dev_err(data->dev, "Error reading bmi323 error register: %d\n", ret);
> +		return ret;
> +	}
> +
> +	if (val) {
> +		dev_err(data->dev, "Sensor power error in PM = 0x%x\n", val);
> +		return -EINVAL;
> +	}
>  
>  	return iio_device_resume_triggering(indio_dev);
>  }
diff mbox series

Patch

diff --git a/drivers/iio/imu/bmi323/bmi323_core.c b/drivers/iio/imu/bmi323/bmi323_core.c
index 4b2b211a3e88..57be22c97cb9 100644
--- a/drivers/iio/imu/bmi323/bmi323_core.c
+++ b/drivers/iio/imu/bmi323/bmi323_core.c
@@ -118,6 +118,38 @@  static const struct bmi323_hw bmi323_hw[2] = {
 	},
 };
 
+static const unsigned int bmi323_reg_savestate[] = {
+	BMI323_INT_MAP1_REG,
+	BMI323_INT_MAP2_REG,
+	BMI323_IO_INT_CTR_REG,
+	BMI323_IO_INT_CONF_REG,
+	BMI323_ACC_CONF_REG,
+	BMI323_GYRO_CONF_REG,
+	BMI323_FEAT_IO0_REG,
+	BMI323_FIFO_WTRMRK_REG,
+	BMI323_FIFO_CONF_REG
+};
+
+static const unsigned int bmi323_ext_reg_savestate[] = {
+	BMI323_GEN_SET1_REG,
+	BMI323_TAP1_REG,
+	BMI323_TAP2_REG,
+	BMI323_TAP3_REG,
+	BMI323_FEAT_IO0_S_TAP_MSK,
+	BMI323_STEP_SC1_REG,
+	BMI323_ANYMO1_REG,
+	BMI323_NOMO1_REG,
+	BMI323_ANYMO1_REG + BMI323_MO2_OFFSET,
+	BMI323_NOMO1_REG + BMI323_MO2_OFFSET,
+	BMI323_ANYMO1_REG + BMI323_MO3_OFFSET,
+	BMI323_NOMO1_REG + BMI323_MO3_OFFSET
+};
+
+struct bmi323_regs_runtime_pm {
+	unsigned int reg_settings[ARRAY_SIZE(bmi323_reg_savestate)];
+	unsigned int ext_reg_settings[ARRAY_SIZE(bmi323_ext_reg_savestate)];
+};
+
 struct bmi323_data {
 	struct device *dev;
 	struct regmap *regmap;
@@ -130,6 +162,7 @@  struct bmi323_data {
 	u32 odrns[BMI323_SENSORS_CNT];
 	u32 odrhz[BMI323_SENSORS_CNT];
 	unsigned int feature_events;
+	struct bmi323_regs_runtime_pm runtime_pm_status;
 
 	/*
 	 * Lock to protect the members of device's private data from concurrent
@@ -1972,6 +2005,11 @@  static void bmi323_disable(void *data_ptr)
 
 	bmi323_set_mode(data, BMI323_ACCEL, ACC_GYRO_MODE_DISABLE);
 	bmi323_set_mode(data, BMI323_GYRO, ACC_GYRO_MODE_DISABLE);
+
+	/*
+	 * Place the peripheral in its lowest power consuming state.
+	 */
+	regmap_write(data->regmap, BMI323_CMD_REG, BMI323_RST_VAL);
 }
 
 static int bmi323_set_bw(struct bmi323_data *data,
@@ -2030,6 +2068,13 @@  static int bmi323_init(struct bmi323_data *data)
 		return dev_err_probe(data->dev, -EINVAL,
 				     "Sensor power error = 0x%x\n", val);
 
+	return 0;
+}
+
+static int bmi323_init_reset(struct bmi323_data *data)
+{
+	int ret;
+
 	/*
 	 * Set the Bandwidth coefficient which defines the 3 dB cutoff
 	 * frequency in relation to the ODR.
@@ -2078,12 +2123,18 @@  int bmi323_core_probe(struct device *dev)
 	data = iio_priv(indio_dev);
 	data->dev = dev;
 	data->regmap = regmap;
+	data->irq_pin = BMI323_IRQ_DISABLED;
+	data->state = BMI323_IDLE;
 	mutex_init(&data->mutex);
 
 	ret = bmi323_init(data);
 	if (ret)
 		return -EINVAL;
 
+	ret = bmi323_init_reset(data);
+	if (ret)
+		return -EINVAL;
+
 	if (!iio_read_acpi_mount_matrix(dev, &data->orientation, "ROTM")) {
 		ret = iio_read_mount_matrix(dev, &data->orientation);
 		if (ret)
@@ -2117,7 +2168,7 @@  int bmi323_core_probe(struct device *dev)
 		return dev_err_probe(data->dev, ret,
 				     "Unable to register iio device\n");
 
-	return 0;
+	return bmi323_fifo_disable(data);
 }
 EXPORT_SYMBOL_NS_GPL(bmi323_core_probe, IIO_BMI323);
 
@@ -2125,13 +2176,113 @@  EXPORT_SYMBOL_NS_GPL(bmi323_core_probe, IIO_BMI323);
 static int bmi323_core_runtime_suspend(struct device *dev)
 {
 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct bmi323_data *data = iio_priv(indio_dev);
+	struct bmi323_regs_runtime_pm *savestate = &data->runtime_pm_status;
+	int ret;
+
+	guard(mutex)(&data->mutex);
+
+	ret = iio_device_suspend_triggering(indio_dev);
+	if (ret)
+		return ret;
+
+	/* Save registers meant to be restored by resume pm callback. */
+	for (unsigned int i = 0; i < ARRAY_SIZE(bmi323_reg_savestate); i++) {
+		ret = regmap_read(data->regmap, bmi323_reg_savestate[i],
+			   &savestate->reg_settings[i]);
+		if (ret) {
+			dev_err(data->dev, "Error reading bmi323 reg 0x%x: %d\n",
+				  bmi323_reg_savestate[i], ret);
+			return ret;
+		}
+	}
+
+	for (unsigned int i = 0; i < ARRAY_SIZE(bmi323_ext_reg_savestate); i++) {
+		ret = bmi323_read_ext_reg(data, bmi323_reg_savestate[i],
+			   &savestate->reg_settings[i]);
+		if (ret) {
+			dev_err(data->dev, "Error reading bmi323 external reg 0x%x: %d\n",
+				  bmi323_reg_savestate[i], ret);
+			return ret;
+		}
+	}
+
+	/* Perform soft reset to place the device in its lowest power state. */
+	ret = regmap_write(data->regmap, BMI323_CMD_REG, BMI323_RST_VAL);
+	if (ret)
+		return ret;
 
-	return iio_device_suspend_triggering(indio_dev);
+	return 0;
 }
 
 static int bmi323_core_runtime_resume(struct device *dev)
 {
 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct bmi323_data *data = iio_priv(indio_dev);
+	struct bmi323_regs_runtime_pm *savestate = &data->runtime_pm_status;
+	unsigned int val;
+	int ret;
+
+	guard(mutex)(&data->mutex);
+
+	/*
+	 * Perform the device power-on and initial setup once again
+	 * after being reset in the lower power state by runtime-pm.
+	 */
+	ret = bmi323_init(data);
+	if (!ret)
+		return ret;
+
+	/* Register must be cleared before changing an active config */
+	ret = regmap_write(data->regmap, BMI323_FEAT_IO0_REG, 0);
+	if (ret) {
+		dev_err(data->dev, "Error stopping feature engine\n");
+		return ret;
+	}
+
+	for (unsigned int i = 0; i < ARRAY_SIZE(bmi323_ext_reg_savestate); i++) {
+		ret = bmi323_write_ext_reg(data, bmi323_reg_savestate[i],
+			  savestate->reg_settings[i]);
+		if (ret) {
+			dev_err(data->dev, "Error writing bmi323 external reg 0x%x: %d\n",
+				  bmi323_reg_savestate[i], ret);
+			return ret;
+		}
+	}
+
+	for (unsigned int i = 0; i < ARRAY_SIZE(bmi323_reg_savestate); i++) {
+		ret = regmap_write(data->regmap, bmi323_reg_savestate[i],
+			  savestate->reg_settings[i]);
+		if (ret) {
+			dev_err(data->dev, "Error writing bmi323 reg 0x%x: %d\n",
+				  bmi323_reg_savestate[i], ret);
+			return ret;
+		}
+	}
+
+	/*
+	 * Clear old FIFO samples that might be generated before suspend
+	 * or generated from a peripheral state not equal to the saved one.
+	 */
+	if (data->state == BMI323_BUFFER_FIFO) {
+		ret = regmap_write(data->regmap, BMI323_FIFO_CTRL_REG,
+			   BMI323_FIFO_FLUSH_MSK);
+		if (ret) {
+			dev_err(data->dev, "Error flushing FIFO buffer: %d\n", ret);
+			return ret;
+		}
+	}
+
+	ret = regmap_read(data->regmap, BMI323_ERR_REG, &val);
+	if (ret) {
+		dev_err(data->dev, "Error reading bmi323 error register: %d\n", ret);
+		return ret;
+	}
+
+	if (val) {
+		dev_err(data->dev, "Sensor power error in PM = 0x%x\n", val);
+		return -EINVAL;
+	}
 
 	return iio_device_resume_triggering(indio_dev);
 }