/* * STMicroelectronics pressures driver * * Copyright 2013 STMicroelectronics Inc. * * Denis Ciocca * * Licensed under the GPL-2. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "st_pressure.h" /* * About determining pressure scaling factors * ------------------------------------------ * * Datasheets specify typical pressure sensitivity so that pressure is computed * according to the following equation : * pressure[mBar] = raw / sensitivity * where : * raw the 24 bits long raw sampled pressure * sensitivity a scaling factor specified by the datasheet in LSB/mBar * * IIO ABI expects pressure to be expressed as kPascal, hence pressure should be * computed according to : * pressure[kPascal] = pressure[mBar] / 10 * = raw / (sensitivity * 10) (1) * * Finally, st_press_read_raw() returns pressure scaling factor as an * IIO_VAL_INT_PLUS_NANO with a zero integral part and "gain" as decimal part. * Therefore, from (1), "gain" becomes : * gain = 10^9 / (sensitivity * 10) * = 10^8 / sensitivity * * About determining temperature scaling factors and offsets * --------------------------------------------------------- * * Datasheets specify typical temperature sensitivity and offset so that * temperature is computed according to the following equation : * temp[Celsius] = offset[Celsius] + (raw / sensitivity) * where : * raw the 16 bits long raw sampled temperature * offset a constant specified by the datasheet in degree Celsius * (sometimes zero) * sensitivity a scaling factor specified by the datasheet in LSB/Celsius * * IIO ABI expects temperature to be expressed as milli degree Celsius such as * user space should compute temperature according to : * temp[mCelsius] = temp[Celsius] * 10^3 * = (offset[Celsius] + (raw / sensitivity)) * 10^3 * = ((offset[Celsius] * sensitivity) + raw) * * (10^3 / sensitivity) (2) * * IIO ABI expects user space to apply offset and scaling factors to raw samples * according to : * temp[mCelsius] = (OFFSET + raw) * SCALE * where : * OFFSET an arbitrary constant exposed by device * SCALE an arbitrary scaling factor exposed by device * * Matching OFFSET and SCALE with members of (2) gives : * OFFSET = offset[Celsius] * sensitivity (3) * SCALE = 10^3 / sensitivity (4) * * st_press_read_raw() returns temperature scaling factor as an * IIO_VAL_FRACTIONAL with a 10^3 numerator and "gain2" as denominator. * Therefore, from (3), "gain2" becomes : * gain2 = sensitivity * * When declared within channel, i.e. for a non zero specified offset, * st_press_read_raw() will return the latter as an IIO_VAL_FRACTIONAL such as : * numerator = OFFSET * 10^3 * denominator = 10^3 * giving from (4): * numerator = offset[Celsius] * 10^3 * sensitivity * = offset[mCelsius] * gain2 */ #define MCELSIUS_PER_CELSIUS 1000 /* Default pressure sensitivity */ #define ST_PRESS_LSB_PER_MBAR 4096UL #define ST_PRESS_KPASCAL_NANO_SCALE (100000000UL / \ ST_PRESS_LSB_PER_MBAR) /* Default temperature sensitivity */ #define ST_PRESS_LSB_PER_CELSIUS 480UL #define ST_PRESS_MILLI_CELSIUS_OFFSET 42500UL /* FULLSCALE */ #define ST_PRESS_FS_AVL_1100MB 1100 #define ST_PRESS_FS_AVL_1260MB 1260 #define ST_PRESS_1_OUT_XL_ADDR 0x28 #define ST_TEMP_1_OUT_L_ADDR 0x2b /* LPS001WP pressure resolution */ #define ST_PRESS_LPS001WP_LSB_PER_MBAR 16UL /* LPS001WP temperature resolution */ #define ST_PRESS_LPS001WP_LSB_PER_CELSIUS 64UL /* LPS001WP pressure gain */ #define ST_PRESS_LPS001WP_FS_AVL_PRESS_GAIN \ (100000000UL / ST_PRESS_LPS001WP_LSB_PER_MBAR) /* LPS001WP pressure and temp L addresses */ #define ST_PRESS_LPS001WP_OUT_L_ADDR 0x28 #define ST_TEMP_LPS001WP_OUT_L_ADDR 0x2a /* LPS25H pressure and temp L addresses */ #define ST_PRESS_LPS25H_OUT_XL_ADDR 0x28 #define ST_TEMP_LPS25H_OUT_L_ADDR 0x2b /* LPS22HB temperature sensitivity */ #define ST_PRESS_LPS22HB_LSB_PER_CELSIUS 100UL static const struct iio_chan_spec st_press_1_channels[] = { { .type = IIO_PRESSURE, .address = ST_PRESS_1_OUT_XL_ADDR, .scan_index = 0, .scan_type = { .sign = 's', .realbits = 24, .storagebits = 32, .endianness = IIO_LE, }, .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), }, { .type = IIO_TEMP, .address = ST_TEMP_1_OUT_L_ADDR, .scan_index = 1, .scan_type = { .sign = 's', .realbits = 16, .storagebits = 16, .endianness = IIO_LE, }, .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_OFFSET), .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), }, IIO_CHAN_SOFT_TIMESTAMP(2) }; static const struct iio_chan_spec st_press_lps001wp_channels[] = { { .type = IIO_PRESSURE, .address = ST_PRESS_LPS001WP_OUT_L_ADDR, .scan_index = 0, .scan_type = { .sign = 's', .realbits = 16, .storagebits = 16, .endianness = IIO_LE, }, .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), }, { .type = IIO_TEMP, .address = ST_TEMP_LPS001WP_OUT_L_ADDR, .scan_index = 1, .scan_type = { .sign = 's', .realbits = 16, .storagebits = 16, .endianness = IIO_LE, }, .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), }, IIO_CHAN_SOFT_TIMESTAMP(2) }; static const struct iio_chan_spec st_press_lps22hb_channels[] = { { .type = IIO_PRESSURE, .address = ST_PRESS_1_OUT_XL_ADDR, .scan_index = 0, .scan_type = { .sign = 's', .realbits = 24, .storagebits = 32, .endianness = IIO_LE, }, .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), }, { .type = IIO_TEMP, .address = ST_TEMP_1_OUT_L_ADDR, .scan_index = 1, .scan_type = { .sign = 's', .realbits = 16, .storagebits = 16, .endianness = IIO_LE, }, .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), }, IIO_CHAN_SOFT_TIMESTAMP(2) }; static const struct st_sensor_settings st_press_sensors_settings[] = { { /* * CUSTOM VALUES FOR LPS331AP SENSOR * See LPS331AP datasheet: * http://www2.st.com/resource/en/datasheet/lps331ap.pdf */ .wai = 0xbb, .wai_addr = ST_SENSORS_DEFAULT_WAI_ADDRESS, .sensors_supported = { [0] = LPS331AP_PRESS_DEV_NAME, }, .ch = (struct iio_chan_spec *)st_press_1_channels, .num_ch = ARRAY_SIZE(st_press_1_channels), .odr = { .addr = 0x20, .mask = 0x70, .odr_avl = { { .hz = 1, .value = 0x01 }, { .hz = 7, .value = 0x05 }, { .hz = 13, .value = 0x06 }, { .hz = 25, .value = 0x07 }, }, }, .pw = { .addr = 0x20, .mask = 0x80, .value_on = ST_SENSORS_DEFAULT_POWER_ON_VALUE, .value_off = ST_SENSORS_DEFAULT_POWER_OFF_VALUE, }, .fs = { .addr = 0x23, .mask = 0x30, .fs_avl = { /* * Pressure and temperature sensitivity values * as defined in table 3 of LPS331AP datasheet. */ [0] = { .num = ST_PRESS_FS_AVL_1260MB, .gain = ST_PRESS_KPASCAL_NANO_SCALE, .gain2 = ST_PRESS_LSB_PER_CELSIUS, }, }, }, .bdu = { .addr = 0x20, .mask = 0x04, }, .drdy_irq = { .int1 = { .addr = 0x22, .mask = 0x04, .addr_od = 0x22, .mask_od = 0x40, }, .int2 = { .addr = 0x22, .mask = 0x20, .addr_od = 0x22, .mask_od = 0x40, }, .addr_ihl = 0x22, .mask_ihl = 0x80, .stat_drdy = { .addr = ST_SENSORS_DEFAULT_STAT_ADDR, .mask = 0x03, }, }, .sim = { .addr = 0x20, .value = BIT(0), }, .multi_read_bit = true, .bootime = 2, }, { /* * CUSTOM VALUES FOR LPS001WP SENSOR */ .wai = 0xba, .wai_addr = ST_SENSORS_DEFAULT_WAI_ADDRESS, .sensors_supported = { [0] = LPS001WP_PRESS_DEV_NAME, }, .ch = (struct iio_chan_spec *)st_press_lps001wp_channels, .num_ch = ARRAY_SIZE(st_press_lps001wp_channels), .odr = { .addr = 0x20, .mask = 0x30, .odr_avl = { { .hz = 1, .value = 0x01 }, { .hz = 7, .value = 0x02 }, { .hz = 13, .value = 0x03 }, }, }, .pw = { .addr = 0x20, .mask = 0x40, .value_on = ST_SENSORS_DEFAULT_POWER_ON_VALUE, .value_off = ST_SENSORS_DEFAULT_POWER_OFF_VALUE, }, .fs = { .fs_avl = { /* * Pressure and temperature resolution values * as defined in table 3 of LPS001WP datasheet. */ [0] = { .num = ST_PRESS_FS_AVL_1100MB, .gain = ST_PRESS_LPS001WP_FS_AVL_PRESS_GAIN, .gain2 = ST_PRESS_LPS001WP_LSB_PER_CELSIUS, }, }, }, .bdu = { .addr = 0x20, .mask = 0x04, }, .sim = { .addr = 0x20, .value = BIT(0), }, .multi_read_bit = true, .bootime = 2, }, { /* * CUSTOM VALUES FOR LPS25H SENSOR * See LPS25H datasheet: * http://www2.st.com/resource/en/datasheet/lps25h.pdf */ .wai = 0xbd, .wai_addr = ST_SENSORS_DEFAULT_WAI_ADDRESS, .sensors_supported = { [0] = LPS25H_PRESS_DEV_NAME, }, .ch = (struct iio_chan_spec *)st_press_1_channels, .num_ch = ARRAY_SIZE(st_press_1_channels), .odr = { .addr = 0x20, .mask = 0x70, .odr_avl = { { .hz = 1, .value = 0x01 }, { .hz = 7, .value = 0x02 }, { .hz = 13, .value = 0x03 }, { .hz = 25, .value = 0x04 }, }, }, .pw = { .addr = 0x20, .mask = 0x80, .value_on = ST_SENSORS_DEFAULT_POWER_ON_VALUE, .value_off = ST_SENSORS_DEFAULT_POWER_OFF_VALUE, }, .fs = { .fs_avl = { /* * Pressure and temperature sensitivity values * as defined in table 3 of LPS25H datasheet. */ [0] = { .num = ST_PRESS_FS_AVL_1260MB, .gain = ST_PRESS_KPASCAL_NANO_SCALE, .gain2 = ST_PRESS_LSB_PER_CELSIUS, }, }, }, .bdu = { .addr = 0x20, .mask = 0x04, }, .drdy_irq = { .int1 = { .addr = 0x23, .mask = 0x01, .addr_od = 0x22, .mask_od = 0x40, }, .addr_ihl = 0x22, .mask_ihl = 0x80, .stat_drdy = { .addr = ST_SENSORS_DEFAULT_STAT_ADDR, .mask = 0x03, }, }, .sim = { .addr = 0x20, .value = BIT(0), }, .multi_read_bit = true, .bootime = 2, }, { /* * CUSTOM VALUES FOR LPS22HB SENSOR * See LPS22HB datasheet: * http://www2.st.com/resource/en/datasheet/lps22hb.pdf */ .wai = 0xb1, .wai_addr = ST_SENSORS_DEFAULT_WAI_ADDRESS, .sensors_supported = { [0] = LPS22HB_PRESS_DEV_NAME, [1] = LPS33HW_PRESS_DEV_NAME, [2] = LPS35HW_PRESS_DEV_NAME, }, .ch = (struct iio_chan_spec *)st_press_lps22hb_channels, .num_ch = ARRAY_SIZE(st_press_lps22hb_channels), .odr = { .addr = 0x10, .mask = 0x70, .odr_avl = { { .hz = 1, .value = 0x01 }, { .hz = 10, .value = 0x02 }, { .hz = 25, .value = 0x03 }, { .hz = 50, .value = 0x04 }, { .hz = 75, .value = 0x05 }, }, }, .pw = { .addr = 0x10, .mask = 0x70, .value_off = ST_SENSORS_DEFAULT_POWER_OFF_VALUE, }, .fs = { .fs_avl = { /* * Pressure and temperature sensitivity values * as defined in table 3 of LPS22HB datasheet. */ [0] = { .num = ST_PRESS_FS_AVL_1260MB, .gain = ST_PRESS_KPASCAL_NANO_SCALE, .gain2 = ST_PRESS_LPS22HB_LSB_PER_CELSIUS, }, }, }, .bdu = { .addr = 0x10, .mask = 0x02, }, .drdy_irq = { .int1 = { .addr = 0x12, .mask = 0x04, .addr_od = 0x12, .mask_od = 0x40, }, .addr_ihl = 0x12, .mask_ihl = 0x80, .stat_drdy = { .addr = ST_SENSORS_DEFAULT_STAT_ADDR, .mask = 0x03, }, }, .sim = { .addr = 0x10, .value = BIT(0), }, .multi_read_bit = false, .bootime = 2, }, { /* * CUSTOM VALUES FOR LPS22HH SENSOR * See LPS22HH datasheet: * http://www2.st.com/resource/en/datasheet/lps22hh.pdf */ .wai = 0xb3, .wai_addr = ST_SENSORS_DEFAULT_WAI_ADDRESS, .sensors_supported = { [0] = LPS22HH_PRESS_DEV_NAME, }, .ch = (struct iio_chan_spec *)st_press_lps22hb_channels, .num_ch = ARRAY_SIZE(st_press_lps22hb_channels), .odr = { .addr = 0x10, .mask = 0x70, .odr_avl = { { .hz = 1, .value = 0x01 }, { .hz = 10, .value = 0x02 }, { .hz = 25, .value = 0x03 }, { .hz = 50, .value = 0x04 }, { .hz = 75, .value = 0x05 }, { .hz = 100, .value = 0x06 }, { .hz = 200, .value = 0x07 }, }, }, .pw = { .addr = 0x10, .mask = 0x70, .value_off = ST_SENSORS_DEFAULT_POWER_OFF_VALUE, }, .fs = { .fs_avl = { /* * Pressure and temperature sensitivity values * as defined in table 3 of LPS22HH datasheet. */ [0] = { .num = ST_PRESS_FS_AVL_1260MB, .gain = ST_PRESS_KPASCAL_NANO_SCALE, .gain2 = ST_PRESS_LPS22HB_LSB_PER_CELSIUS, }, }, }, .bdu = { .addr = 0x10, .mask = BIT(1), }, .drdy_irq = { .int1 = { .addr = 0x12, .mask = BIT(2), .addr_od = 0x11, .mask_od = BIT(5), }, .addr_ihl = 0x11, .mask_ihl = BIT(6), .stat_drdy = { .addr = ST_SENSORS_DEFAULT_STAT_ADDR, .mask = 0x03, }, }, .sim = { .addr = 0x10, .value = BIT(0), }, .multi_read_bit = false, .bootime = 2, }, }; static int st_press_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *ch, int val, int val2, long mask) { int err; switch (mask) { case IIO_CHAN_INFO_SAMP_FREQ: if (val2) return -EINVAL; mutex_lock(&indio_dev->mlock); err = st_sensors_set_odr(indio_dev, val); mutex_unlock(&indio_dev->mlock); return err; default: return -EINVAL; } } static int st_press_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *ch, int *val, int *val2, long mask) { int err; struct st_sensor_data *press_data = iio_priv(indio_dev); switch (mask) { case IIO_CHAN_INFO_RAW: err = st_sensors_read_info_raw(indio_dev, ch, val); if (err < 0) goto read_error; return IIO_VAL_INT; case IIO_CHAN_INFO_SCALE: switch (ch->type) { case IIO_PRESSURE: *val = 0; *val2 = press_data->current_fullscale->gain; return IIO_VAL_INT_PLUS_NANO; case IIO_TEMP: *val = MCELSIUS_PER_CELSIUS; *val2 = press_data->current_fullscale->gain2; return IIO_VAL_FRACTIONAL; default: err = -EINVAL; goto read_error; } case IIO_CHAN_INFO_OFFSET: switch (ch->type) { case IIO_TEMP: *val = ST_PRESS_MILLI_CELSIUS_OFFSET * press_data->current_fullscale->gain2; *val2 = MCELSIUS_PER_CELSIUS; break; default: err = -EINVAL; goto read_error; } return IIO_VAL_FRACTIONAL; case IIO_CHAN_INFO_SAMP_FREQ: *val = press_data->odr; return IIO_VAL_INT; default: return -EINVAL; } read_error: return err; } static ST_SENSORS_DEV_ATTR_SAMP_FREQ_AVAIL(); static struct attribute *st_press_attributes[] = { &iio_dev_attr_sampling_frequency_available.dev_attr.attr, NULL, }; static const struct attribute_group st_press_attribute_group = { .attrs = st_press_attributes, }; static const struct iio_info press_info = { .attrs = &st_press_attribute_group, .read_raw = &st_press_read_raw, .write_raw = &st_press_write_raw, .debugfs_reg_access = &st_sensors_debugfs_reg_access, }; #ifdef CONFIG_IIO_TRIGGER static const struct iio_trigger_ops st_press_trigger_ops = { .set_trigger_state = ST_PRESS_TRIGGER_SET_STATE, .validate_device = st_sensors_validate_device, }; #define ST_PRESS_TRIGGER_OPS (&st_press_trigger_ops) #else #define ST_PRESS_TRIGGER_OPS NULL #endif int st_press_common_probe(struct iio_dev *indio_dev) { struct st_sensor_data *press_data = iio_priv(indio_dev); struct st_sensors_platform_data *pdata = (struct st_sensors_platform_data *)press_data->dev->platform_data; int irq = press_data->get_irq_data_ready(indio_dev); int err; indio_dev->modes = INDIO_DIRECT_MODE; indio_dev->info = &press_info; mutex_init(&press_data->tb.buf_lock); err = st_sensors_power_enable(indio_dev); if (err) return err; err = st_sensors_check_device_support(indio_dev, ARRAY_SIZE(st_press_sensors_settings), st_press_sensors_settings); if (err < 0) goto st_press_power_off; /* * Skip timestamping channel while declaring available channels to * common st_sensor layer. Look at st_sensors_get_buffer_element() to * see how timestamps are explicitly pushed as last samples block * element. */ press_data->num_data_channels = press_data->sensor_settings->num_ch - 1; press_data->multiread_bit = press_data->sensor_settings->multi_read_bit; indio_dev->channels = press_data->sensor_settings->ch; indio_dev->num_channels = press_data->sensor_settings->num_ch; press_data->current_fullscale = (struct st_sensor_fullscale_avl *) &press_data->sensor_settings->fs.fs_avl[0]; press_data->odr = press_data->sensor_settings->odr.odr_avl[0].hz; /* Some devices don't support a data ready pin. */ if (!pdata && (press_data->sensor_settings->drdy_irq.int1.addr || press_data->sensor_settings->drdy_irq.int2.addr)) pdata = (struct st_sensors_platform_data *)&default_press_pdata; err = st_sensors_init_sensor(indio_dev, pdata); if (err < 0) goto st_press_power_off; err = st_press_allocate_ring(indio_dev); if (err < 0) goto st_press_power_off; if (irq > 0) { err = st_sensors_allocate_trigger(indio_dev, ST_PRESS_TRIGGER_OPS); if (err < 0) goto st_press_probe_trigger_error; } err = iio_device_register(indio_dev); if (err) goto st_press_device_register_error; dev_info(&indio_dev->dev, "registered pressure sensor %s\n", indio_dev->name); return err; st_press_device_register_error: if (irq > 0) st_sensors_deallocate_trigger(indio_dev); st_press_probe_trigger_error: st_press_deallocate_ring(indio_dev); st_press_power_off: st_sensors_power_disable(indio_dev); return err; } EXPORT_SYMBOL(st_press_common_probe); void st_press_common_remove(struct iio_dev *indio_dev) { struct st_sensor_data *press_data = iio_priv(indio_dev); st_sensors_power_disable(indio_dev); iio_device_unregister(indio_dev); if (press_data->get_irq_data_ready(indio_dev) > 0) st_sensors_deallocate_trigger(indio_dev); st_press_deallocate_ring(indio_dev); } EXPORT_SYMBOL(st_press_common_remove); MODULE_AUTHOR("Denis Ciocca "); MODULE_DESCRIPTION("STMicroelectronics pressures driver"); MODULE_LICENSE("GPL v2");