/* * MS5611 pressure and temperature sensor driver * * Copyright (c) Tomasz Duszynski * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * Data sheet: * http://www.meas-spec.com/downloads/MS5611-01BA03.pdf * http://www.meas-spec.com/downloads/MS5607-02BA03.pdf * */ #include #include #include #include #include #include #include #include #include "ms5611.h" #define MS5611_INIT_OSR(_cmd, _conv_usec, _rate) \ { .cmd = _cmd, .conv_usec = _conv_usec, .rate = _rate } static const struct ms5611_osr ms5611_avail_pressure_osr[] = { MS5611_INIT_OSR(0x40, 600, 256), MS5611_INIT_OSR(0x42, 1170, 512), MS5611_INIT_OSR(0x44, 2280, 1024), MS5611_INIT_OSR(0x46, 4540, 2048), MS5611_INIT_OSR(0x48, 9040, 4096) }; static const struct ms5611_osr ms5611_avail_temp_osr[] = { MS5611_INIT_OSR(0x50, 600, 256), MS5611_INIT_OSR(0x52, 1170, 512), MS5611_INIT_OSR(0x54, 2280, 1024), MS5611_INIT_OSR(0x56, 4540, 2048), MS5611_INIT_OSR(0x58, 9040, 4096) }; static const char ms5611_show_osr[] = "256 512 1024 2048 4096"; static IIO_CONST_ATTR(oversampling_ratio_available, ms5611_show_osr); static struct attribute *ms5611_attributes[] = { &iio_const_attr_oversampling_ratio_available.dev_attr.attr, NULL, }; static const struct attribute_group ms5611_attribute_group = { .attrs = ms5611_attributes, }; static bool ms5611_prom_is_valid(u16 *prom, size_t len) { int i, j; uint16_t crc = 0, crc_orig = prom[7] & 0x000F; prom[7] &= 0xFF00; for (i = 0; i < len * 2; i++) { if (i % 2 == 1) crc ^= prom[i >> 1] & 0x00FF; else crc ^= prom[i >> 1] >> 8; for (j = 0; j < 8; j++) { if (crc & 0x8000) crc = (crc << 1) ^ 0x3000; else crc <<= 1; } } crc = (crc >> 12) & 0x000F; return crc_orig != 0x0000 && crc == crc_orig; } static int ms5611_read_prom(struct iio_dev *indio_dev) { int ret, i; struct ms5611_state *st = iio_priv(indio_dev); for (i = 0; i < MS5611_PROM_WORDS_NB; i++) { ret = st->read_prom_word(st, i, &st->prom[i]); if (ret < 0) { dev_err(&indio_dev->dev, "failed to read prom at %d\n", i); return ret; } } if (!ms5611_prom_is_valid(st->prom, MS5611_PROM_WORDS_NB)) { dev_err(&indio_dev->dev, "PROM integrity check failed\n"); return -ENODEV; } return 0; } static int ms5611_read_temp_and_pressure(struct iio_dev *indio_dev, s32 *temp, s32 *pressure) { int ret; struct ms5611_state *st = iio_priv(indio_dev); ret = st->read_adc_temp_and_pressure(st, temp, pressure); if (ret < 0) { dev_err(&indio_dev->dev, "failed to read temperature and pressure\n"); return ret; } return st->compensate_temp_and_pressure(st, temp, pressure); } static int ms5611_temp_and_pressure_compensate(struct ms5611_state *st, s32 *temp, s32 *pressure) { s32 t = *temp, p = *pressure; s64 off, sens, dt; dt = t - (st->prom[5] << 8); off = ((s64)st->prom[2] << 16) + ((st->prom[4] * dt) >> 7); sens = ((s64)st->prom[1] << 15) + ((st->prom[3] * dt) >> 8); t = 2000 + ((st->prom[6] * dt) >> 23); if (t < 2000) { s64 off2, sens2, t2; t2 = (dt * dt) >> 31; off2 = (5 * (t - 2000) * (t - 2000)) >> 1; sens2 = off2 >> 1; if (t < -1500) { s64 tmp = (t + 1500) * (t + 1500); off2 += 7 * tmp; sens2 += (11 * tmp) >> 1; } t -= t2; off -= off2; sens -= sens2; } *temp = t; *pressure = (((p * sens) >> 21) - off) >> 15; return 0; } static int ms5607_temp_and_pressure_compensate(struct ms5611_state *st, s32 *temp, s32 *pressure) { s32 t = *temp, p = *pressure; s64 off, sens, dt; dt = t - (st->prom[5] << 8); off = ((s64)st->prom[2] << 17) + ((st->prom[4] * dt) >> 6); sens = ((s64)st->prom[1] << 16) + ((st->prom[3] * dt) >> 7); t = 2000 + ((st->prom[6] * dt) >> 23); if (t < 2000) { s64 off2, sens2, t2, tmp; t2 = (dt * dt) >> 31; tmp = (t - 2000) * (t - 2000); off2 = (61 * tmp) >> 4; sens2 = tmp << 1; if (t < -1500) { tmp = (t + 1500) * (t + 1500); off2 += 15 * tmp; sens2 += 8 * tmp; } t -= t2; off -= off2; sens -= sens2; } *temp = t; *pressure = (((p * sens) >> 21) - off) >> 15; return 0; } static int ms5611_reset(struct iio_dev *indio_dev) { int ret; struct ms5611_state *st = iio_priv(indio_dev); ret = st->reset(st); if (ret < 0) { dev_err(&indio_dev->dev, "failed to reset device\n"); return ret; } usleep_range(3000, 4000); return 0; } static irqreturn_t ms5611_trigger_handler(int irq, void *p) { struct iio_poll_func *pf = p; struct iio_dev *indio_dev = pf->indio_dev; struct ms5611_state *st = iio_priv(indio_dev); /* Ensure buffer elements are naturally aligned */ struct { s32 channels[2]; s64 ts __aligned(8); } scan; int ret; mutex_lock(&st->lock); ret = ms5611_read_temp_and_pressure(indio_dev, &scan.channels[1], &scan.channels[0]); mutex_unlock(&st->lock); if (ret < 0) goto err; iio_push_to_buffers_with_timestamp(indio_dev, &scan, iio_get_time_ns(indio_dev)); err: iio_trigger_notify_done(indio_dev->trig); return IRQ_HANDLED; } static int ms5611_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val, int *val2, long mask) { int ret; s32 temp, pressure; struct ms5611_state *st = iio_priv(indio_dev); switch (mask) { case IIO_CHAN_INFO_PROCESSED: mutex_lock(&st->lock); ret = ms5611_read_temp_and_pressure(indio_dev, &temp, &pressure); mutex_unlock(&st->lock); if (ret < 0) return ret; switch (chan->type) { case IIO_TEMP: *val = temp * 10; return IIO_VAL_INT; case IIO_PRESSURE: *val = pressure / 1000; *val2 = (pressure % 1000) * 1000; return IIO_VAL_INT_PLUS_MICRO; default: return -EINVAL; } case IIO_CHAN_INFO_SCALE: switch (chan->type) { case IIO_TEMP: *val = 10; return IIO_VAL_INT; case IIO_PRESSURE: *val = 0; *val2 = 1000; return IIO_VAL_INT_PLUS_MICRO; default: return -EINVAL; } case IIO_CHAN_INFO_OVERSAMPLING_RATIO: if (chan->type != IIO_TEMP && chan->type != IIO_PRESSURE) break; mutex_lock(&st->lock); if (chan->type == IIO_TEMP) *val = (int)st->temp_osr->rate; else *val = (int)st->pressure_osr->rate; mutex_unlock(&st->lock); return IIO_VAL_INT; } return -EINVAL; } static const struct ms5611_osr *ms5611_find_osr(int rate, const struct ms5611_osr *osr, size_t count) { unsigned int r; for (r = 0; r < count; r++) if ((unsigned short)rate == osr[r].rate) break; if (r >= count) return NULL; return &osr[r]; } static int ms5611_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int val, int val2, long mask) { struct ms5611_state *st = iio_priv(indio_dev); const struct ms5611_osr *osr = NULL; int ret; if (mask != IIO_CHAN_INFO_OVERSAMPLING_RATIO) return -EINVAL; if (chan->type == IIO_TEMP) osr = ms5611_find_osr(val, ms5611_avail_temp_osr, ARRAY_SIZE(ms5611_avail_temp_osr)); else if (chan->type == IIO_PRESSURE) osr = ms5611_find_osr(val, ms5611_avail_pressure_osr, ARRAY_SIZE(ms5611_avail_pressure_osr)); if (!osr) return -EINVAL; ret = iio_device_claim_direct_mode(indio_dev); if (ret) return ret; mutex_lock(&st->lock); if (chan->type == IIO_TEMP) st->temp_osr = osr; else st->pressure_osr = osr; mutex_unlock(&st->lock); iio_device_release_direct_mode(indio_dev); return 0; } static const unsigned long ms5611_scan_masks[] = {0x3, 0}; static const struct iio_chan_spec ms5611_channels[] = { { .type = IIO_PRESSURE, .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) | BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), .scan_index = 0, .scan_type = { .sign = 's', .realbits = 32, .storagebits = 32, .endianness = IIO_CPU, }, }, { .type = IIO_TEMP, .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) | BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), .scan_index = 1, .scan_type = { .sign = 's', .realbits = 32, .storagebits = 32, .endianness = IIO_CPU, }, }, IIO_CHAN_SOFT_TIMESTAMP(2), }; static const struct iio_info ms5611_info = { .read_raw = &ms5611_read_raw, .write_raw = &ms5611_write_raw, .attrs = &ms5611_attribute_group, }; static int ms5611_init(struct iio_dev *indio_dev) { int ret; struct ms5611_state *st = iio_priv(indio_dev); /* Enable attached regulator if any. */ st->vdd = devm_regulator_get(indio_dev->dev.parent, "vdd"); if (IS_ERR(st->vdd)) return PTR_ERR(st->vdd); ret = regulator_enable(st->vdd); if (ret) { dev_err(indio_dev->dev.parent, "failed to enable Vdd supply: %d\n", ret); return ret; } ret = ms5611_reset(indio_dev); if (ret < 0) goto err_regulator_disable; ret = ms5611_read_prom(indio_dev); if (ret < 0) goto err_regulator_disable; return 0; err_regulator_disable: regulator_disable(st->vdd); return ret; } static void ms5611_fini(const struct iio_dev *indio_dev) { const struct ms5611_state *st = iio_priv(indio_dev); regulator_disable(st->vdd); } int ms5611_probe(struct iio_dev *indio_dev, struct device *dev, const char *name, int type) { int ret; struct ms5611_state *st = iio_priv(indio_dev); mutex_init(&st->lock); switch (type) { case MS5611: st->compensate_temp_and_pressure = ms5611_temp_and_pressure_compensate; break; case MS5607: st->compensate_temp_and_pressure = ms5607_temp_and_pressure_compensate; break; default: return -EINVAL; } st->temp_osr = &ms5611_avail_temp_osr[ARRAY_SIZE(ms5611_avail_temp_osr) - 1]; st->pressure_osr = &ms5611_avail_pressure_osr[ARRAY_SIZE(ms5611_avail_pressure_osr) - 1]; indio_dev->dev.parent = dev; indio_dev->name = name; indio_dev->info = &ms5611_info; indio_dev->channels = ms5611_channels; indio_dev->num_channels = ARRAY_SIZE(ms5611_channels); indio_dev->modes = INDIO_DIRECT_MODE; indio_dev->available_scan_masks = ms5611_scan_masks; ret = ms5611_init(indio_dev); if (ret < 0) return ret; ret = iio_triggered_buffer_setup(indio_dev, NULL, ms5611_trigger_handler, NULL); if (ret < 0) { dev_err(dev, "iio triggered buffer setup failed\n"); goto err_fini; } ret = iio_device_register(indio_dev); if (ret < 0) { dev_err(dev, "unable to register iio device\n"); goto err_buffer_cleanup; } return 0; err_buffer_cleanup: iio_triggered_buffer_cleanup(indio_dev); err_fini: ms5611_fini(indio_dev); return ret; } EXPORT_SYMBOL(ms5611_probe); int ms5611_remove(struct iio_dev *indio_dev) { iio_device_unregister(indio_dev); iio_triggered_buffer_cleanup(indio_dev); ms5611_fini(indio_dev); return 0; } EXPORT_SYMBOL(ms5611_remove); MODULE_AUTHOR("Tomasz Duszynski "); MODULE_DESCRIPTION("MS5611 core driver"); MODULE_LICENSE("GPL v2");