/* * mma8452.c - Support for Freescale MMA8452Q 3-axis 12-bit accelerometer * * Copyright 2014 Peter Meerwald * * This file is subject to the terms and conditions of version 2 of * the GNU General Public License. See the file COPYING in the main * directory of this archive for more details. * * 7-bit I2C slave address 0x1c/0x1d (pin selectable) * * TODO: orientation / freefall events, autosleep */ #include #include #include #include #include #include #include #include #include #include #define MMA8452_STATUS 0x00 #define MMA8452_STATUS_DRDY (BIT(2) | BIT(1) | BIT(0)) #define MMA8452_OUT_X 0x01 /* MSB first, 12-bit */ #define MMA8452_OUT_Y 0x03 #define MMA8452_OUT_Z 0x05 #define MMA8452_INT_SRC 0x0c #define MMA8452_WHO_AM_I 0x0d #define MMA8452_DATA_CFG 0x0e #define MMA8452_DATA_CFG_FS_MASK GENMASK(1, 0) #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_HP_FILTER_CUTOFF 0x0f #define MMA8452_HP_FILTER_CUTOFF_SEL_MASK GENMASK(1, 0) #define MMA8452_TRANSIENT_CFG 0x1d #define MMA8452_TRANSIENT_CFG_HPF_BYP BIT(0) #define MMA8452_TRANSIENT_CFG_CHAN(chan) BIT(chan + 1) #define MMA8452_TRANSIENT_CFG_ELE BIT(4) #define MMA8452_TRANSIENT_SRC 0x1e #define MMA8452_TRANSIENT_SRC_XTRANSE BIT(1) #define MMA8452_TRANSIENT_SRC_YTRANSE BIT(3) #define MMA8452_TRANSIENT_SRC_ZTRANSE BIT(5) #define MMA8452_TRANSIENT_THS 0x1f #define MMA8452_TRANSIENT_THS_MASK GENMASK(6, 0) #define MMA8452_TRANSIENT_COUNT 0x20 #define MMA8452_CTRL_REG1 0x2a #define MMA8452_CTRL_ACTIVE BIT(0) #define MMA8452_CTRL_DR_MASK GENMASK(5, 3) #define MMA8452_CTRL_DR_SHIFT 3 #define MMA8452_CTRL_DR_DEFAULT 0x4 /* 50 Hz sample frequency */ #define MMA8452_CTRL_REG2 0x2b #define MMA8452_CTRL_REG2_RST BIT(6) #define MMA8452_CTRL_REG4 0x2d #define MMA8452_CTRL_REG5 0x2e #define MMA8452_OFF_X 0x2f #define MMA8452_OFF_Y 0x30 #define MMA8452_OFF_Z 0x31 #define MMA8452_MAX_REG 0x31 #define MMA8452_INT_DRDY BIT(0) #define MMA8452_INT_TRANS BIT(5) #define MMA8452_DEVICE_ID 0x2a struct mma8452_data { struct i2c_client *client; struct mutex lock; u8 ctrl_reg1; u8 data_cfg; }; static int mma8452_drdy(struct mma8452_data *data) { int tries = 150; while (tries-- > 0) { int ret = i2c_smbus_read_byte_data(data->client, MMA8452_STATUS); if (ret < 0) return ret; if ((ret & MMA8452_STATUS_DRDY) == MMA8452_STATUS_DRDY) return 0; msleep(20); } dev_err(&data->client->dev, "data not ready\n"); return -EIO; } static int mma8452_read(struct mma8452_data *data, __be16 buf[3]) { int ret = mma8452_drdy(data); if (ret < 0) return ret; return i2c_smbus_read_i2c_block_data(data->client, MMA8452_OUT_X, 3 * sizeof(__be16), (u8 *)buf); } static ssize_t mma8452_show_int_plus_micros(char *buf, const int (*vals)[2], int n) { size_t len = 0; while (n-- > 0) len += scnprintf(buf + len, PAGE_SIZE - len, "%d.%06d ", vals[n][0], vals[n][1]); /* replace trailing space by newline */ buf[len - 1] = '\n'; return len; } static int mma8452_get_int_plus_micros_index(const int (*vals)[2], int n, int val, int val2) { while (n-- > 0) if (val == vals[n][0] && val2 == vals[n][1]) return n; return -EINVAL; } static int mma8452_get_odr_index(struct mma8452_data *data) { return (data->ctrl_reg1 & MMA8452_CTRL_DR_MASK) >> MMA8452_CTRL_DR_SHIFT; } static const int mma8452_samp_freq[8][2] = { {800, 0}, {400, 0}, {200, 0}, {100, 0}, {50, 0}, {12, 500000}, {6, 250000}, {1, 560000} }; /* * Hardware has fullscale of -2G, -4G, -8G corresponding to raw value -2048 * The userspace interface uses m/s^2 and we declare micro units * So scale factor is given by: * g * N * 1000000 / 2048 for N = 2, 4, 8 and g = 9.80665 */ static const int mma8452_scales[3][2] = { {0, 9577}, {0, 19154}, {0, 38307} }; /* Datasheet table 35 (step time vs sample frequency) */ static const int mma8452_transient_time_step_us[8] = { 1250, 2500, 5000, 10000, 20000, 20000, 20000, 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) { return mma8452_show_int_plus_micros(buf, mma8452_samp_freq, ARRAY_SIZE(mma8452_samp_freq)); } static ssize_t mma8452_show_scale_avail(struct device *dev, struct device_attribute *attr, char *buf) { return mma8452_show_int_plus_micros(buf, mma8452_scales, 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) { return mma8452_get_int_plus_micros_index(mma8452_samp_freq, ARRAY_SIZE(mma8452_samp_freq), val, val2); } static int mma8452_get_scale_index(struct mma8452_data *data, int val, int val2) { return mma8452_get_int_plus_micros_index(mma8452_scales, 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_hp_filter_cutoff[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) { struct mma8452_data *data = iio_priv(indio_dev); __be16 buffer[3]; int i, ret; switch (mask) { case IIO_CHAN_INFO_RAW: if (iio_buffer_enabled(indio_dev)) return -EBUSY; mutex_lock(&data->lock); ret = mma8452_read(data, buffer); mutex_unlock(&data->lock); if (ret < 0) return ret; *val = sign_extend32(be16_to_cpu(buffer[chan->scan_index]) >> 4, 11); return IIO_VAL_INT; case IIO_CHAN_INFO_SCALE: i = data->data_cfg & MMA8452_DATA_CFG_FS_MASK; *val = mma8452_scales[i][0]; *val2 = mma8452_scales[i][1]; return IIO_VAL_INT_PLUS_MICRO; case IIO_CHAN_INFO_SAMP_FREQ: i = mma8452_get_odr_index(data); *val = mma8452_samp_freq[i][0]; *val2 = mma8452_samp_freq[i][1]; return IIO_VAL_INT_PLUS_MICRO; case IIO_CHAN_INFO_CALIBBIAS: ret = i2c_smbus_read_byte_data(data->client, MMA8452_OFF_X + chan->scan_index); if (ret < 0) 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; } static int mma8452_standby(struct mma8452_data *data) { return i2c_smbus_write_byte_data(data->client, MMA8452_CTRL_REG1, data->ctrl_reg1 & ~MMA8452_CTRL_ACTIVE); } static int mma8452_active(struct mma8452_data *data) { return i2c_smbus_write_byte_data(data->client, MMA8452_CTRL_REG1, data->ctrl_reg1); } static int mma8452_change_config(struct mma8452_data *data, u8 reg, u8 val) { int ret; mutex_lock(&data->lock); /* config can only be changed when in standby */ ret = mma8452_standby(data); if (ret < 0) goto fail; ret = i2c_smbus_write_byte_data(data->client, reg, val); if (ret < 0) goto fail; ret = mma8452_active(data); if (ret < 0) goto fail; ret = 0; fail: mutex_unlock(&data->lock); 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 i; 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, ret; if (iio_buffer_enabled(indio_dev)) return -EBUSY; switch (mask) { case IIO_CHAN_INFO_SAMP_FREQ: i = mma8452_get_samp_freq_index(data, val, val2); if (i < 0) return i; data->ctrl_reg1 &= ~MMA8452_CTRL_DR_MASK; data->ctrl_reg1 |= i << MMA8452_CTRL_DR_SHIFT; return mma8452_change_config(data, MMA8452_CTRL_REG1, data->ctrl_reg1); case IIO_CHAN_INFO_SCALE: i = mma8452_get_scale_index(data, val, val2); if (i < 0) return i; data->data_cfg &= ~MMA8452_DATA_CFG_FS_MASK; data->data_cfg |= i; return mma8452_change_config(data, MMA8452_DATA_CFG, data->data_cfg); case IIO_CHAN_INFO_CALIBBIAS: if (val < -128 || val > 127) 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; } } static int mma8452_read_thresh(struct iio_dev *indio_dev, const struct iio_chan_spec *chan, enum iio_event_type type, enum iio_event_direction dir, enum iio_event_info info, int *val, int *val2) { struct mma8452_data *data = iio_priv(indio_dev); int ret, us; switch (info) { case IIO_EV_INFO_VALUE: ret = i2c_smbus_read_byte_data(data->client, MMA8452_TRANSIENT_THS); if (ret < 0) return ret; *val = ret & MMA8452_TRANSIENT_THS_MASK; return IIO_VAL_INT; case IIO_EV_INFO_PERIOD: ret = i2c_smbus_read_byte_data(data->client, MMA8452_TRANSIENT_COUNT); if (ret < 0) return ret; us = ret * mma8452_transient_time_step_us[ mma8452_get_odr_index(data)]; *val = us / USEC_PER_SEC; *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; } } static int mma8452_write_thresh(struct iio_dev *indio_dev, const struct iio_chan_spec *chan, enum iio_event_type type, enum iio_event_direction dir, enum iio_event_info info, int val, int val2) { struct mma8452_data *data = iio_priv(indio_dev); int ret, reg, steps; switch (info) { case IIO_EV_INFO_VALUE: if (val < 0 || val > MMA8452_TRANSIENT_THS_MASK) return -EINVAL; return mma8452_change_config(data, MMA8452_TRANSIENT_THS, val); case IIO_EV_INFO_PERIOD: steps = (val * USEC_PER_SEC + val2) / mma8452_transient_time_step_us[ mma8452_get_odr_index(data)]; if (steps < 0 || steps > 0xff) return -EINVAL; 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; } } static int mma8452_read_event_config(struct iio_dev *indio_dev, const struct iio_chan_spec *chan, enum iio_event_type type, enum iio_event_direction dir) { struct mma8452_data *data = iio_priv(indio_dev); int ret; ret = i2c_smbus_read_byte_data(data->client, MMA8452_TRANSIENT_CFG); if (ret < 0) return ret; return ret & MMA8452_TRANSIENT_CFG_CHAN(chan->scan_index) ? 1 : 0; } static int mma8452_write_event_config(struct iio_dev *indio_dev, const struct iio_chan_spec *chan, enum iio_event_type type, enum iio_event_direction dir, int state) { struct mma8452_data *data = iio_priv(indio_dev); int val; val = i2c_smbus_read_byte_data(data->client, MMA8452_TRANSIENT_CFG); if (val < 0) return val; if (state) val |= MMA8452_TRANSIENT_CFG_CHAN(chan->scan_index); else val &= ~MMA8452_TRANSIENT_CFG_CHAN(chan->scan_index); val |= MMA8452_TRANSIENT_CFG_ELE; return mma8452_change_config(data, MMA8452_TRANSIENT_CFG, val); } static void mma8452_transient_interrupt(struct iio_dev *indio_dev) { struct mma8452_data *data = iio_priv(indio_dev); s64 ts = iio_get_time_ns(); int src; src = i2c_smbus_read_byte_data(data->client, MMA8452_TRANSIENT_SRC); if (src < 0) return; if (src & MMA8452_TRANSIENT_SRC_XTRANSE) iio_push_event(indio_dev, IIO_MOD_EVENT_CODE(IIO_ACCEL, 0, IIO_MOD_X, IIO_EV_TYPE_MAG, IIO_EV_DIR_RISING), ts); if (src & MMA8452_TRANSIENT_SRC_YTRANSE) iio_push_event(indio_dev, IIO_MOD_EVENT_CODE(IIO_ACCEL, 0, IIO_MOD_Y, IIO_EV_TYPE_MAG, IIO_EV_DIR_RISING), ts); if (src & MMA8452_TRANSIENT_SRC_ZTRANSE) iio_push_event(indio_dev, IIO_MOD_EVENT_CODE(IIO_ACCEL, 0, IIO_MOD_Z, IIO_EV_TYPE_MAG, IIO_EV_DIR_RISING), ts); } static irqreturn_t mma8452_interrupt(int irq, void *p) { struct iio_dev *indio_dev = p; struct mma8452_data *data = iio_priv(indio_dev); int ret = IRQ_NONE; int src; src = i2c_smbus_read_byte_data(data->client, MMA8452_INT_SRC); if (src < 0) return IRQ_NONE; if (src & MMA8452_INT_DRDY) { iio_trigger_poll_chained(indio_dev->trig); ret = IRQ_HANDLED; } if (src & MMA8452_INT_TRANS) { mma8452_transient_interrupt(indio_dev); ret = IRQ_HANDLED; } return ret; } static irqreturn_t mma8452_trigger_handler(int irq, void *p) { struct iio_poll_func *pf = p; struct iio_dev *indio_dev = pf->indio_dev; struct mma8452_data *data = iio_priv(indio_dev); u8 buffer[16]; /* 3 16-bit channels + padding + ts */ int ret; ret = mma8452_read(data, (__be16 *)buffer); if (ret < 0) goto done; iio_push_to_buffers_with_timestamp(indio_dev, buffer, iio_get_time_ns()); done: iio_trigger_notify_done(indio_dev->trig); return IRQ_HANDLED; } static int mma8452_reg_access_dbg(struct iio_dev *indio_dev, unsigned reg, unsigned writeval, unsigned *readval) { int ret; struct mma8452_data *data = iio_priv(indio_dev); if (reg > MMA8452_MAX_REG) return -EINVAL; if (!readval) return mma8452_change_config(data, reg, writeval); ret = i2c_smbus_read_byte_data(data->client, reg); if (ret < 0) return ret; *readval = ret; return 0; } static const struct iio_event_spec mma8452_transient_event[] = { { .type = IIO_EV_TYPE_MAG, .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_HIGH_PASS_FILTER_3DB) }, }; /* * Threshold is configured in fixed 8G/127 steps regardless of * currently selected scale for measurement. */ static IIO_CONST_ATTR_NAMED(accel_transient_scale, in_accel_scale, "0.617742"); static struct attribute *mma8452_event_attributes[] = { &iio_const_attr_accel_transient_scale.dev_attr.attr, NULL, }; static struct attribute_group mma8452_event_attribute_group = { .attrs = mma8452_event_attributes, .name = "events", }; #define MMA8452_CHANNEL(axis, idx) { \ .type = IIO_ACCEL, \ .modified = 1, \ .channel2 = IIO_MOD_##axis, \ .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_HIGH_PASS_FILTER_3DB_FREQUENCY), \ .scan_index = idx, \ .scan_type = { \ .sign = 's', \ .realbits = 12, \ .storagebits = 16, \ .shift = 4, \ .endianness = IIO_BE, \ }, \ .event_spec = mma8452_transient_event, \ .num_event_specs = ARRAY_SIZE(mma8452_transient_event), \ } static const struct iio_chan_spec mma8452_channels[] = { MMA8452_CHANNEL(X, 0), MMA8452_CHANNEL(Y, 1), MMA8452_CHANNEL(Z, 2), IIO_CHAN_SOFT_TIMESTAMP(3), }; 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 }; static const struct attribute_group mma8452_group = { .attrs = mma8452_attributes, }; static const struct iio_info mma8452_info = { .attrs = &mma8452_group, .read_raw = &mma8452_read_raw, .write_raw = &mma8452_write_raw, .event_attrs = &mma8452_event_attribute_group, .read_event_value = &mma8452_read_thresh, .write_event_value = &mma8452_write_thresh, .read_event_config = &mma8452_read_event_config, .write_event_config = &mma8452_write_event_config, .debugfs_reg_access = &mma8452_reg_access_dbg, .driver_module = THIS_MODULE, }; static const unsigned long mma8452_scan_masks[] = {0x7, 0}; static int mma8452_data_rdy_trigger_set_state(struct iio_trigger *trig, bool state) { struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig); struct mma8452_data *data = iio_priv(indio_dev); int reg; reg = i2c_smbus_read_byte_data(data->client, MMA8452_CTRL_REG4); if (reg < 0) return reg; if (state) reg |= MMA8452_INT_DRDY; else reg &= ~MMA8452_INT_DRDY; return mma8452_change_config(data, MMA8452_CTRL_REG4, reg); } static int mma8452_validate_device(struct iio_trigger *trig, struct iio_dev *indio_dev) { struct iio_dev *indio = iio_trigger_get_drvdata(trig); if (indio != indio_dev) return -EINVAL; return 0; } static const struct iio_trigger_ops mma8452_trigger_ops = { .set_trigger_state = mma8452_data_rdy_trigger_set_state, .validate_device = mma8452_validate_device, .owner = THIS_MODULE, }; static int mma8452_trigger_setup(struct iio_dev *indio_dev) { struct mma8452_data *data = iio_priv(indio_dev); struct iio_trigger *trig; int ret; trig = devm_iio_trigger_alloc(&data->client->dev, "%s-dev%d", indio_dev->name, indio_dev->id); if (!trig) return -ENOMEM; trig->dev.parent = &data->client->dev; trig->ops = &mma8452_trigger_ops; iio_trigger_set_drvdata(trig, indio_dev); ret = iio_trigger_register(trig); if (ret) return ret; indio_dev->trig = trig; return 0; } static void mma8452_trigger_cleanup(struct iio_dev *indio_dev) { if (indio_dev->trig) iio_trigger_unregister(indio_dev->trig); } static int mma8452_reset(struct i2c_client *client) { int i; int ret; ret = i2c_smbus_write_byte_data(client, MMA8452_CTRL_REG2, MMA8452_CTRL_REG2_RST); if (ret < 0) return ret; for (i = 0; i < 10; i++) { usleep_range(100, 200); ret = i2c_smbus_read_byte_data(client, MMA8452_CTRL_REG2); if (ret == -EIO) continue; /* I2C comm reset */ if (ret < 0) return ret; if (!(ret & MMA8452_CTRL_REG2_RST)) return 0; } return -ETIMEDOUT; } static int mma8452_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct mma8452_data *data; struct iio_dev *indio_dev; int ret; ret = i2c_smbus_read_byte_data(client, MMA8452_WHO_AM_I); if (ret < 0) return ret; if (ret != MMA8452_DEVICE_ID) return -ENODEV; indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); if (!indio_dev) return -ENOMEM; data = iio_priv(indio_dev); data->client = client; mutex_init(&data->lock); i2c_set_clientdata(client, indio_dev); indio_dev->info = &mma8452_info; indio_dev->name = id->name; indio_dev->dev.parent = &client->dev; indio_dev->modes = INDIO_DIRECT_MODE; indio_dev->channels = mma8452_channels; indio_dev->num_channels = ARRAY_SIZE(mma8452_channels); indio_dev->available_scan_masks = mma8452_scan_masks; ret = mma8452_reset(client); if (ret < 0) return ret; data->data_cfg = MMA8452_DATA_CFG_FS_2G; ret = i2c_smbus_write_byte_data(client, MMA8452_DATA_CFG, data->data_cfg); if (ret < 0) return ret; /* * By default set transient threshold to max to avoid events if * enabling without configuring threshold. */ ret = i2c_smbus_write_byte_data(client, MMA8452_TRANSIENT_THS, MMA8452_TRANSIENT_THS_MASK); if (ret < 0) return ret; if (client->irq) { /* * Although we enable the transient interrupt source once and * for all here the transient event detection itself is not * enabled until userspace asks for it by * mma8452_write_event_config() */ int supported_interrupts = MMA8452_INT_DRDY | MMA8452_INT_TRANS; int enabled_interrupts = MMA8452_INT_TRANS; /* Assume wired to INT1 pin */ ret = i2c_smbus_write_byte_data(client, MMA8452_CTRL_REG5, supported_interrupts); if (ret < 0) return ret; ret = i2c_smbus_write_byte_data(client, MMA8452_CTRL_REG4, enabled_interrupts); if (ret < 0) return ret; ret = mma8452_trigger_setup(indio_dev); if (ret < 0) return ret; } data->ctrl_reg1 = MMA8452_CTRL_ACTIVE | (MMA8452_CTRL_DR_DEFAULT << MMA8452_CTRL_DR_SHIFT); ret = i2c_smbus_write_byte_data(client, MMA8452_CTRL_REG1, data->ctrl_reg1); if (ret < 0) goto trigger_cleanup; ret = iio_triggered_buffer_setup(indio_dev, NULL, mma8452_trigger_handler, NULL); if (ret < 0) goto trigger_cleanup; if (client->irq) { ret = devm_request_threaded_irq(&client->dev, client->irq, NULL, mma8452_interrupt, IRQF_TRIGGER_LOW | IRQF_ONESHOT, client->name, indio_dev); if (ret) goto buffer_cleanup; } ret = iio_device_register(indio_dev); if (ret < 0) goto buffer_cleanup; return 0; buffer_cleanup: iio_triggered_buffer_cleanup(indio_dev); trigger_cleanup: mma8452_trigger_cleanup(indio_dev); return ret; } static int mma8452_remove(struct i2c_client *client) { struct iio_dev *indio_dev = i2c_get_clientdata(client); iio_device_unregister(indio_dev); iio_triggered_buffer_cleanup(indio_dev); mma8452_trigger_cleanup(indio_dev); mma8452_standby(iio_priv(indio_dev)); return 0; } #ifdef CONFIG_PM_SLEEP static int mma8452_suspend(struct device *dev) { return mma8452_standby(iio_priv(i2c_get_clientdata( to_i2c_client(dev)))); } static int mma8452_resume(struct device *dev) { return mma8452_active(iio_priv(i2c_get_clientdata( to_i2c_client(dev)))); } static SIMPLE_DEV_PM_OPS(mma8452_pm_ops, mma8452_suspend, mma8452_resume); #define MMA8452_PM_OPS (&mma8452_pm_ops) #else #define MMA8452_PM_OPS NULL #endif static const struct i2c_device_id mma8452_id[] = { { "mma8452", 0 }, { } }; MODULE_DEVICE_TABLE(i2c, mma8452_id); static const struct of_device_id mma8452_dt_ids[] = { { .compatible = "fsl,mma8452" }, { } }; MODULE_DEVICE_TABLE(of, mma8452_dt_ids); static struct i2c_driver mma8452_driver = { .driver = { .name = "mma8452", .of_match_table = of_match_ptr(mma8452_dt_ids), .pm = MMA8452_PM_OPS, }, .probe = mma8452_probe, .remove = mma8452_remove, .id_table = mma8452_id, }; module_i2c_driver(mma8452_driver); MODULE_AUTHOR("Peter Meerwald "); MODULE_DESCRIPTION("Freescale MMA8452 accelerometer driver"); MODULE_LICENSE("GPL");