/* * bma180.c - IIO driver for Bosch BMA180 triaxial acceleration sensor * * Copyright 2013 Oleksandr Kravchenko * * 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. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define BMA180_DRV_NAME "bma180" #define BMA180_IRQ_NAME "bma180_event" /* Register set */ #define BMA180_CHIP_ID 0x00 /* Need to distinguish BMA180 from other */ #define BMA180_ACC_X_LSB 0x02 /* First of 6 registers of accel data */ #define BMA180_CTRL_REG0 0x0d #define BMA180_RESET 0x10 #define BMA180_BW_TCS 0x20 #define BMA180_CTRL_REG3 0x21 #define BMA180_TCO_Z 0x30 #define BMA180_OFFSET_LSB1 0x35 /* BMA180_CTRL_REG0 bits */ #define BMA180_DIS_WAKE_UP BIT(0) /* Disable wake up mode */ #define BMA180_SLEEP BIT(1) /* 1 - chip will sleep */ #define BMA180_EE_W BIT(4) /* Unlock writing to addr from 0x20 */ #define BMA180_RESET_INT BIT(6) /* Reset pending interrupts */ /* BMA180_CTRL_REG3 bits */ #define BMA180_NEW_DATA_INT BIT(1) /* Intr every new accel data is ready */ /* BMA180_OFFSET_LSB1 skipping mode bit */ #define BMA180_SMP_SKIP BIT(0) /* Bit masks for registers bit fields */ #define BMA180_RANGE 0x0e /* Range of measured accel values*/ #define BMA180_BW 0xf0 /* Accel bandwidth */ #define BMA180_MODE_CONFIG 0x03 /* Config operation modes */ /* We have to write this value in reset register to do soft reset */ #define BMA180_RESET_VAL 0xb6 #define BMA_180_ID_REG_VAL 0x03 /* Chip power modes */ #define BMA180_LOW_NOISE 0x00 #define BMA180_LOW_POWER 0x03 #define BMA180_LOW_NOISE_STR "low_noise" #define BMA180_LOW_POWER_STR "low_power" /* Defaults values */ #define BMA180_DEF_PMODE 0 #define BMA180_DEF_BW 20 #define BMA180_DEF_SCALE 2452 /* Available values for sysfs */ #define BMA180_FLP_FREQ_AVAILABLE \ "10 20 40 75 150 300" #define BMA180_SCALE_AVAILABLE \ "0.001275 0.001863 0.002452 0.003727 0.004903 0.009709 0.019417" struct bma180_data { struct i2c_client *client; struct iio_trigger *trig; struct mutex mutex; int sleep_state; int scale; int bw; int pmode; char *buff; }; enum bma180_axis { AXIS_X, AXIS_Y, AXIS_Z, }; static int bw_table[] = { 10, 20, 40, 75, 150, 300 }; /* Hz */ static int scale_table[] = { 1275, 1863, 2452, 3727, 4903, 9709, 19417 }; static int bma180_get_acc_reg(struct bma180_data *data, enum bma180_axis axis) { u8 reg = BMA180_ACC_X_LSB + axis * 2; int ret; if (data->sleep_state) return -EBUSY; ret = i2c_smbus_read_word_data(data->client, reg); if (ret < 0) dev_err(&data->client->dev, "failed to read accel_%c registers\n", 'x' + axis); return ret; } static int bma180_set_bits(struct bma180_data *data, u8 reg, u8 mask, u8 val) { int ret = i2c_smbus_read_byte_data(data->client, reg); u8 reg_val = (ret & ~mask) | (val << (ffs(mask) - 1)); if (ret < 0) return ret; return i2c_smbus_write_byte_data(data->client, reg, reg_val); } static int bma180_reset_intr(struct bma180_data *data) { int ret = bma180_set_bits(data, BMA180_CTRL_REG0, BMA180_RESET_INT, 1); if (ret) dev_err(&data->client->dev, "failed to reset interrupt\n"); return ret; } static int bma180_set_new_data_intr_state(struct bma180_data *data, int state) { u8 reg_val = state ? BMA180_NEW_DATA_INT : 0x00; int ret = i2c_smbus_write_byte_data(data->client, BMA180_CTRL_REG3, reg_val); if (ret) goto err; ret = bma180_reset_intr(data); if (ret) goto err; return 0; err: dev_err(&data->client->dev, "failed to set new data interrupt state %d\n", state); return ret; } static int bma180_set_sleep_state(struct bma180_data *data, int state) { int ret = bma180_set_bits(data, BMA180_CTRL_REG0, BMA180_SLEEP, state); if (ret) { dev_err(&data->client->dev, "failed to set sleep state %d\n", state); return ret; } data->sleep_state = state; return 0; } static int bma180_set_ee_writing_state(struct bma180_data *data, int state) { int ret = bma180_set_bits(data, BMA180_CTRL_REG0, BMA180_EE_W, state); if (ret) dev_err(&data->client->dev, "failed to set ee writing state %d\n", state); return ret; } static int bma180_set_bw(struct bma180_data *data, int val) { int ret, i; if (data->sleep_state) return -EBUSY; for (i = 0; i < ARRAY_SIZE(bw_table); ++i) { if (bw_table[i] == val) { ret = bma180_set_bits(data, BMA180_BW_TCS, BMA180_BW, i); if (ret) { dev_err(&data->client->dev, "failed to set bandwidth\n"); return ret; } data->bw = val; return 0; } } return -EINVAL; } static int bma180_set_scale(struct bma180_data *data, int val) { int ret, i; if (data->sleep_state) return -EBUSY; for (i = 0; i < ARRAY_SIZE(scale_table); ++i) if (scale_table[i] == val) { ret = bma180_set_bits(data, BMA180_OFFSET_LSB1, BMA180_RANGE, i); if (ret) { dev_err(&data->client->dev, "failed to set scale\n"); return ret; } data->scale = val; return 0; } return -EINVAL; } static int bma180_set_pmode(struct bma180_data *data, int mode) { u8 reg_val = mode ? BMA180_LOW_POWER : BMA180_LOW_NOISE; int ret = bma180_set_bits(data, BMA180_TCO_Z, BMA180_MODE_CONFIG, reg_val); if (ret) { dev_err(&data->client->dev, "failed to set power mode\n"); return ret; } data->pmode = mode; return 0; } static int bma180_soft_reset(struct bma180_data *data) { int ret = i2c_smbus_write_byte_data(data->client, BMA180_RESET, BMA180_RESET_VAL); if (ret) dev_err(&data->client->dev, "failed to reset the chip\n"); return ret; } static int bma180_chip_init(struct bma180_data *data) { /* Try to read chip_id register. It must return 0x03. */ int ret = i2c_smbus_read_byte_data(data->client, BMA180_CHIP_ID); if (ret < 0) goto err; if (ret != BMA_180_ID_REG_VAL) { ret = -ENODEV; goto err; } ret = bma180_soft_reset(data); if (ret) goto err; /* * No serial transaction should occur within minimum 10 us * after soft_reset command */ msleep(20); ret = bma180_set_bits(data, BMA180_CTRL_REG0, BMA180_DIS_WAKE_UP, 1); if (ret) goto err; ret = bma180_set_ee_writing_state(data, 1); if (ret) goto err; ret = bma180_set_new_data_intr_state(data, 0); if (ret) goto err; ret = bma180_set_bits(data, BMA180_OFFSET_LSB1, BMA180_SMP_SKIP, 1); if (ret) goto err; ret = bma180_set_pmode(data, BMA180_DEF_PMODE); if (ret) goto err; ret = bma180_set_bw(data, BMA180_DEF_BW); if (ret) goto err; ret = bma180_set_scale(data, BMA180_DEF_SCALE); if (ret) goto err; return 0; err: dev_err(&data->client->dev, "failed to init the chip\n"); return ret; } static void bma180_chip_disable(struct bma180_data *data) { if (bma180_set_new_data_intr_state(data, 0)) goto err; if (bma180_set_ee_writing_state(data, 0)) goto err; if (bma180_set_sleep_state(data, 1)) goto err; return; err: dev_err(&data->client->dev, "failed to disable the chip\n"); } static IIO_CONST_ATTR(in_accel_filter_low_pass_3db_frequency_available, BMA180_FLP_FREQ_AVAILABLE); static IIO_CONST_ATTR(in_accel_scale_available, BMA180_SCALE_AVAILABLE); static struct attribute *bma180_attributes[] = { &iio_const_attr_in_accel_filter_low_pass_3db_frequency_available.dev_attr.attr, &iio_const_attr_in_accel_scale_available.dev_attr.attr, NULL, }; static const struct attribute_group bma180_attrs_group = { .attrs = bma180_attributes, }; static int bma180_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val, int *val2, long mask) { struct bma180_data *data = iio_priv(indio_dev); int ret; switch (mask) { case IIO_CHAN_INFO_RAW: mutex_lock(&data->mutex); if (iio_buffer_enabled(indio_dev)) ret = -EBUSY; else ret = bma180_get_acc_reg(data, chan->scan_index); mutex_unlock(&data->mutex); if (ret < 0) return ret; *val = (s16)ret >> chan->scan_type.shift; return IIO_VAL_INT; case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: *val = data->bw; return IIO_VAL_INT; case IIO_CHAN_INFO_SCALE: *val = 0; *val2 = data->scale; return IIO_VAL_INT_PLUS_MICRO; default: return -EINVAL; } } static int bma180_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int val, int val2, long mask) { struct bma180_data *data = iio_priv(indio_dev); int ret; switch (mask) { case IIO_CHAN_INFO_SCALE: if (val) return -EINVAL; mutex_lock(&data->mutex); ret = bma180_set_scale(data, val2); mutex_unlock(&data->mutex); return ret; case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: if (val2) return -EINVAL; mutex_lock(&data->mutex); ret = bma180_set_bw(data, val); mutex_unlock(&data->mutex); return ret; default: return -EINVAL; } } static int bma180_update_scan_mode(struct iio_dev *indio_dev, const unsigned long *scan_mask) { struct bma180_data *data = iio_priv(indio_dev); if (data->buff) devm_kfree(&indio_dev->dev, data->buff); data->buff = devm_kzalloc(&indio_dev->dev, indio_dev->scan_bytes, GFP_KERNEL); if (!data->buff) return -ENOMEM; return 0; } static const struct iio_info bma180_info = { .attrs = &bma180_attrs_group, .read_raw = bma180_read_raw, .write_raw = bma180_write_raw, .update_scan_mode = bma180_update_scan_mode, .driver_module = THIS_MODULE, }; static const char * const bma180_power_modes[] = { BMA180_LOW_NOISE_STR, BMA180_LOW_POWER_STR, }; static int bma180_get_power_mode(struct iio_dev *indio_dev, const struct iio_chan_spec *chan) { struct bma180_data *data = iio_priv(indio_dev); return data->pmode; } static int bma180_set_power_mode(struct iio_dev *indio_dev, const struct iio_chan_spec *chan, unsigned int mode) { struct bma180_data *data = iio_priv(indio_dev); int ret; mutex_lock(&data->mutex); ret = bma180_set_pmode(data, mode); mutex_unlock(&data->mutex); return ret; } static const struct iio_enum bma180_power_mode_enum = { .items = bma180_power_modes, .num_items = ARRAY_SIZE(bma180_power_modes), .get = bma180_get_power_mode, .set = bma180_set_power_mode, }; static const struct iio_chan_spec_ext_info bma180_ext_info[] = { IIO_ENUM("power_mode", true, &bma180_power_mode_enum), IIO_ENUM_AVAILABLE("power_mode", &bma180_power_mode_enum), { }, }; #define BMA180_CHANNEL(_axis) { \ .type = IIO_ACCEL, \ .modified = 1, \ .channel2 = IIO_MOD_##_axis, \ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY), \ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ .scan_index = AXIS_##_axis, \ .scan_type = { \ .sign = 's', \ .realbits = 14, \ .storagebits = 16, \ .shift = 2, \ }, \ .ext_info = bma180_ext_info, \ } static const struct iio_chan_spec bma180_channels[] = { BMA180_CHANNEL(X), BMA180_CHANNEL(Y), BMA180_CHANNEL(Z), IIO_CHAN_SOFT_TIMESTAMP(3), }; static irqreturn_t bma180_trigger_handler(int irq, void *p) { struct iio_poll_func *pf = p; struct iio_dev *indio_dev = pf->indio_dev; struct bma180_data *data = iio_priv(indio_dev); int64_t time_ns = iio_get_time_ns(); int bit, ret, i = 0; mutex_lock(&data->mutex); for_each_set_bit(bit, indio_dev->buffer->scan_mask, indio_dev->masklength) { ret = bma180_get_acc_reg(data, bit); if (ret < 0) { mutex_unlock(&data->mutex); goto err; } ((s16 *)data->buff)[i++] = ret; } mutex_unlock(&data->mutex); iio_push_to_buffers_with_timestamp(indio_dev, data->buff, time_ns); err: iio_trigger_notify_done(indio_dev->trig); return IRQ_HANDLED; } static int bma180_data_rdy_trigger_set_state(struct iio_trigger *trig, bool state) { struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig); struct bma180_data *data = iio_priv(indio_dev); return bma180_set_new_data_intr_state(data, state); } static int bma180_trig_try_reen(struct iio_trigger *trig) { struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig); struct bma180_data *data = iio_priv(indio_dev); return bma180_reset_intr(data); } static const struct iio_trigger_ops bma180_trigger_ops = { .set_trigger_state = bma180_data_rdy_trigger_set_state, .try_reenable = bma180_trig_try_reen, .owner = THIS_MODULE, }; static int bma180_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct bma180_data *data; struct iio_dev *indio_dev; struct iio_trigger *trig; int ret; indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); if (!indio_dev) return -ENOMEM; data = iio_priv(indio_dev); i2c_set_clientdata(client, indio_dev); data->client = client; ret = bma180_chip_init(data); if (ret < 0) goto err_chip_disable; mutex_init(&data->mutex); indio_dev->dev.parent = &client->dev; indio_dev->channels = bma180_channels; indio_dev->num_channels = ARRAY_SIZE(bma180_channels); indio_dev->name = BMA180_DRV_NAME; indio_dev->modes = INDIO_DIRECT_MODE; indio_dev->info = &bma180_info; trig = iio_trigger_alloc("%s-dev%d", indio_dev->name, indio_dev->id); if (!trig) { ret = -ENOMEM; goto err_chip_disable; } ret = devm_request_irq(&client->dev, client->irq, iio_trigger_generic_data_rdy_poll, IRQF_TRIGGER_RISING, BMA180_IRQ_NAME, trig); if (ret) { dev_err(&client->dev, "unable to request IRQ\n"); goto err_trigger_free; } trig->dev.parent = &client->dev; trig->ops = &bma180_trigger_ops; iio_trigger_set_drvdata(trig, indio_dev); data->trig = trig; indio_dev->trig = iio_trigger_get(trig); ret = iio_trigger_register(trig); if (ret) goto err_trigger_free; ret = iio_triggered_buffer_setup(indio_dev, NULL, bma180_trigger_handler, NULL); if (ret < 0) { dev_err(&client->dev, "unable to setup iio triggered buffer\n"); goto err_trigger_unregister; } ret = iio_device_register(indio_dev); if (ret < 0) { dev_err(&client->dev, "unable to register iio device\n"); goto err_buffer_cleanup; } return 0; err_buffer_cleanup: iio_triggered_buffer_cleanup(indio_dev); err_trigger_unregister: iio_trigger_unregister(trig); err_trigger_free: iio_trigger_free(trig); err_chip_disable: bma180_chip_disable(data); return ret; } static int bma180_remove(struct i2c_client *client) { struct iio_dev *indio_dev = i2c_get_clientdata(client); struct bma180_data *data = iio_priv(indio_dev); iio_device_unregister(indio_dev); iio_triggered_buffer_cleanup(indio_dev); iio_trigger_unregister(data->trig); iio_trigger_free(data->trig); mutex_lock(&data->mutex); bma180_chip_disable(data); mutex_unlock(&data->mutex); return 0; } #ifdef CONFIG_PM_SLEEP static int bma180_suspend(struct device *dev) { struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev)); struct bma180_data *data = iio_priv(indio_dev); int ret; mutex_lock(&data->mutex); ret = bma180_set_sleep_state(data, 1); mutex_unlock(&data->mutex); return ret; } static int bma180_resume(struct device *dev) { struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev)); struct bma180_data *data = iio_priv(indio_dev); int ret; mutex_lock(&data->mutex); ret = bma180_set_sleep_state(data, 0); mutex_unlock(&data->mutex); return ret; } static SIMPLE_DEV_PM_OPS(bma180_pm_ops, bma180_suspend, bma180_resume); #define BMA180_PM_OPS (&bma180_pm_ops) #else #define BMA180_PM_OPS NULL #endif static struct i2c_device_id bma180_id[] = { { BMA180_DRV_NAME, 0 }, { } }; MODULE_DEVICE_TABLE(i2c, bma180_id); static struct i2c_driver bma180_driver = { .driver = { .name = BMA180_DRV_NAME, .owner = THIS_MODULE, .pm = BMA180_PM_OPS, }, .probe = bma180_probe, .remove = bma180_remove, .id_table = bma180_id, }; module_i2c_driver(bma180_driver); MODULE_AUTHOR("Kravchenko Oleksandr "); MODULE_AUTHOR("Texas Instruments, Inc."); MODULE_DESCRIPTION("Bosch BMA180 triaxial acceleration sensor"); MODULE_LICENSE("GPL");