iio: mma8452: Add highpass filter configuration. (1e79841a) · Commits · git / linux-nf

drivers/iio/accel/mma8452.c

+136 −4

Original line number	Diff line number	Diff line
		@@ -29,9 +29,12 @@
		#define MMA8452_INT_SRC 0x0c
		#define MMA8452_WHO_AM_I 0x0d
		#define MMA8452_DATA_CFG 0x0e
		#define MMA8452_HP_FILTER_CUTOFF 0x0f
		#define MMA8452_HP_FILTER_CUTOFF_SEL_MASK (BIT(0) \| BIT(1))
		#define MMA8452_TRANSIENT_CFG 0x1d
		#define MMA8452_TRANSIENT_CFG_ELE BIT(4)
		#define MMA8452_TRANSIENT_CFG_CHAN(chan) BIT(chan + 1)
		#define MMA8452_TRANSIENT_CFG_HPF_BYP BIT(0)
		#define MMA8452_TRANSIENT_SRC 0x1e
		#define MMA8452_TRANSIENT_SRC_XTRANSE BIT(1)
		#define MMA8452_TRANSIENT_SRC_YTRANSE BIT(3)
		@@ -61,6 +64,7 @@
		#define MMA8452_DATA_CFG_FS_2G 0
		#define MMA8452_DATA_CFG_FS_4G 1
		#define MMA8452_DATA_CFG_FS_8G 2
		#define MMA8452_DATA_CFG_HPF_MASK BIT(4)

		#define MMA8452_INT_TRANS BIT(5)

		@@ -158,6 +162,18 @@ static const int mma8452_transient_time_step_us[8] = {
		20000
		};

		/* Datasheet table 18 (normal mode) */
		static const int mma8452_hp_filter_cutoff[8][4][2] = {
		{ {16, 0}, {8, 0}, {4, 0}, {2, 0} }, /* 800 Hz sample */
		{ {16, 0}, {8, 0}, {4, 0}, {2, 0} }, /* 400 Hz sample */
		{ {8, 0}, {4, 0}, {2, 0}, {1, 0} }, /* 200 Hz sample */
		{ {4, 0}, {2, 0}, {1, 0}, {0, 500000} }, /* 100 Hz sample */
		{ {2, 0}, {1, 0}, {0, 500000}, {0, 250000} }, /* 50 Hz sample */
		{ {2, 0}, {1, 0}, {0, 500000}, {0, 250000} }, /* 12.5 Hz sample */
		{ {2, 0}, {1, 0}, {0, 500000}, {0, 250000} }, /* 6.25 Hz sample */
		{ {2, 0}, {1, 0}, {0, 500000}, {0, 250000} } /* 1.56 Hz sample */
		};

		static ssize_t mma8452_show_samp_freq_avail(struct device *dev,
		struct device_attribute attr, char buf)
		{
		@@ -172,9 +188,23 @@ static ssize_t mma8452_show_scale_avail(struct device *dev,
		ARRAY_SIZE(mma8452_scales));
		}

		static ssize_t mma8452_show_hp_cutoff_avail(struct device *dev,
		struct device_attribute *attr,
		char *buf)
		{
		struct iio_dev *indio_dev = dev_to_iio_dev(dev);
		struct mma8452_data *data = iio_priv(indio_dev);
		int i = mma8452_get_odr_index(data);

		return mma8452_show_int_plus_micros(buf, mma8452_hp_filter_cutoff[i],
		ARRAY_SIZE(mma8452_hp_filter_cutoff[0]));
		}

		static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(mma8452_show_samp_freq_avail);
		static IIO_DEVICE_ATTR(in_accel_scale_available, S_IRUGO,
		mma8452_show_scale_avail, NULL, 0);
		static IIO_DEVICE_ATTR(in_accel_filter_high_pass_3db_frequency_available,
		S_IRUGO, mma8452_show_hp_cutoff_avail, NULL, 0);

		static int mma8452_get_samp_freq_index(struct mma8452_data *data,
		int val, int val2)
		@@ -190,6 +220,31 @@ static int mma8452_get_scale_index(struct mma8452_data *data,
		ARRAY_SIZE(mma8452_scales), val, val2);
		}

		static int mma8452_get_hp_filter_index(struct mma8452_data *data,
		int val, int val2)
		{
		int i = mma8452_get_odr_index(data);

		return mma8452_get_int_plus_micros_index(mma8452_hp_filter_cutoff[i],
		ARRAY_SIZE(mma8452_scales[0]), val, val2);
		}

		static int mma8452_read_hp_filter(struct mma8452_data data, int hz, int *uHz)
		{
		int i, ret;

		ret = i2c_smbus_read_byte_data(data->client, MMA8452_HP_FILTER_CUTOFF);
		if (ret < 0)
		return ret;

		i = mma8452_get_odr_index(data);
		ret &= MMA8452_HP_FILTER_CUTOFF_SEL_MASK;
		*hz = mma8452_hp_filter_cutoff[i][ret][0];
		*uHz = mma8452_hp_filter_cutoff[i][ret][1];

		return 0;
		}

		static int mma8452_read_raw(struct iio_dev *indio_dev,
		struct iio_chan_spec const *chan,
		int val, int val2, long mask)
		@@ -228,6 +283,16 @@ static int mma8452_read_raw(struct iio_dev *indio_dev,
		return ret;
		*val = sign_extend32(ret, 7);
		return IIO_VAL_INT;
		case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
		if (data->data_cfg & MMA8452_DATA_CFG_HPF_MASK) {
		ret = mma8452_read_hp_filter(data, val, val2);
		if (ret < 0)
		return ret;
		} else {
		*val = 0;
		*val2 = 0;
		}
		return IIO_VAL_INT_PLUS_MICRO;
		}
		return -EINVAL;
		}
		@@ -269,12 +334,31 @@ static int mma8452_change_config(struct mma8452_data *data, u8 reg, u8 val)
		return ret;
		}

		static int mma8452_set_hp_filter_frequency(struct mma8452_data *data,
		int val, int val2)
		{
		int i, reg;

		i = mma8452_get_hp_filter_index(data, val, val2);
		if (i < 0)
		return -EINVAL;

		reg = i2c_smbus_read_byte_data(data->client,
		MMA8452_HP_FILTER_CUTOFF);
		if (reg < 0)
		return reg;
		reg &= ~MMA8452_HP_FILTER_CUTOFF_SEL_MASK;
		reg \|= i;

		return mma8452_change_config(data, MMA8452_HP_FILTER_CUTOFF, reg);
		}

		static int mma8452_write_raw(struct iio_dev *indio_dev,
		struct iio_chan_spec const *chan,
		int val, int val2, long mask)
		{
		struct mma8452_data *data = iio_priv(indio_dev);
		int i;
		int i, ret;

		if (iio_buffer_enabled(indio_dev))
		return -EBUSY;
		@@ -302,6 +386,19 @@ static int mma8452_write_raw(struct iio_dev *indio_dev,
		return -EINVAL;
		return mma8452_change_config(data, MMA8452_OFF_X +
		chan->scan_index, val);

		case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
		if (val == 0 && val2 == 0) {
		data->data_cfg &= ~MMA8452_DATA_CFG_HPF_MASK;
		} else {
		data->data_cfg \|= MMA8452_DATA_CFG_HPF_MASK;
		ret = mma8452_set_hp_filter_frequency(data, val, val2);
		if (ret < 0)
		return ret;
		}
		return mma8452_change_config(data, MMA8452_DATA_CFG,
		data->data_cfg);

		default:
		return -EINVAL;
		}
		@@ -339,6 +436,22 @@ static int mma8452_read_thresh(struct iio_dev *indio_dev,
		*val2 = us % USEC_PER_SEC;
		return IIO_VAL_INT_PLUS_MICRO;

		case IIO_EV_INFO_HIGH_PASS_FILTER_3DB:
		ret = i2c_smbus_read_byte_data(data->client,
		MMA8452_TRANSIENT_CFG);
		if (ret < 0)
		return ret;

		if (ret & MMA8452_TRANSIENT_CFG_HPF_BYP) {
		*val = 0;
		*val2 = 0;
		} else {
		ret = mma8452_read_hp_filter(data, val, val2);
		if (ret < 0)
		return ret;
		}
		return IIO_VAL_INT_PLUS_MICRO;

		default:
		return -EINVAL;
		}
		@@ -352,7 +465,7 @@ static int mma8452_write_thresh(struct iio_dev *indio_dev,
		int val, int val2)
		{
		struct mma8452_data *data = iio_priv(indio_dev);
		int steps;
		int ret, reg, steps;

		switch (info) {
		case IIO_EV_INFO_VALUE:
		@@ -369,6 +482,22 @@ static int mma8452_write_thresh(struct iio_dev *indio_dev,

		return mma8452_change_config(data, MMA8452_TRANSIENT_COUNT,
		steps);
		case IIO_EV_INFO_HIGH_PASS_FILTER_3DB:
		reg = i2c_smbus_read_byte_data(data->client,
		MMA8452_TRANSIENT_CFG);
		if (reg < 0)
		return reg;

		if (val == 0 && val2 == 0) {
		reg \|= MMA8452_TRANSIENT_CFG_HPF_BYP;
		} else {
		reg &= ~MMA8452_TRANSIENT_CFG_HPF_BYP;
		ret = mma8452_set_hp_filter_frequency(data, val, val2);
		if (ret < 0)
		return ret;
		}
		return mma8452_change_config(data, MMA8452_TRANSIENT_CFG, reg);

		default:
		return -EINVAL;
		}
		@@ -510,7 +639,8 @@ static const struct iio_event_spec mma8452_transient_event[] = {
		.dir = IIO_EV_DIR_RISING,
		.mask_separate = BIT(IIO_EV_INFO_ENABLE),
		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE) \|
		BIT(IIO_EV_INFO_PERIOD)
		BIT(IIO_EV_INFO_PERIOD) \|
		BIT(IIO_EV_INFO_HIGH_PASS_FILTER_3DB)
		},
		};

		@@ -537,7 +667,8 @@ static struct attribute_group mma8452_event_attribute_group = {
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) \| \
		BIT(IIO_CHAN_INFO_CALIBBIAS), \
		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ) \| \
		BIT(IIO_CHAN_INFO_SCALE), \
		BIT(IIO_CHAN_INFO_SCALE) \| \
		BIT(IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY), \
		.scan_index = idx, \
		.scan_type = { \
		.sign = 's', \
		@@ -560,6 +691,7 @@ static const struct iio_chan_spec mma8452_channels[] = {
		static struct attribute *mma8452_attributes[] = {
		&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
		&iio_dev_attr_in_accel_scale_available.dev_attr.attr,
		&iio_dev_attr_in_accel_filter_high_pass_3db_frequency_available.dev_attr.attr,
		NULL
		};