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Diffstat (limited to 'drivers/iio/pressure/ms5611_core.c')
-rw-r--r--drivers/iio/pressure/ms5611_core.c493
1 files changed, 493 insertions, 0 deletions
diff --git a/drivers/iio/pressure/ms5611_core.c b/drivers/iio/pressure/ms5611_core.c
new file mode 100644
index 000000000..f4ea886fd
--- /dev/null
+++ b/drivers/iio/pressure/ms5611_core.c
@@ -0,0 +1,493 @@
+/*
+ * MS5611 pressure and temperature sensor driver
+ *
+ * Copyright (c) Tomasz Duszynski <tduszyns@gmail.com>
+ *
+ * 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 <linux/module.h>
+#include <linux/iio/iio.h>
+#include <linux/delay.h>
+#include <linux/regulator/consumer.h>
+
+#include <linux/iio/sysfs.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
+#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(&indio_dev->dev,
+ i, &st->chip_info->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->chip_info->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(&indio_dev->dev, temp, pressure);
+ if (ret < 0) {
+ dev_err(&indio_dev->dev,
+ "failed to read temperature and pressure\n");
+ return ret;
+ }
+
+ return st->chip_info->temp_and_pressure_compensate(st->chip_info,
+ temp, pressure);
+}
+
+static int ms5611_temp_and_pressure_compensate(struct ms5611_chip_info *chip_info,
+ s32 *temp, s32 *pressure)
+{
+ s32 t = *temp, p = *pressure;
+ s64 off, sens, dt;
+
+ dt = t - (chip_info->prom[5] << 8);
+ off = ((s64)chip_info->prom[2] << 16) + ((chip_info->prom[4] * dt) >> 7);
+ sens = ((s64)chip_info->prom[1] << 15) + ((chip_info->prom[3] * dt) >> 8);
+
+ t = 2000 + ((chip_info->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_chip_info *chip_info,
+ s32 *temp, s32 *pressure)
+{
+ s32 t = *temp, p = *pressure;
+ s64 off, sens, dt;
+
+ dt = t - (chip_info->prom[5] << 8);
+ off = ((s64)chip_info->prom[2] << 17) + ((chip_info->prom[4] * dt) >> 6);
+ sens = ((s64)chip_info->prom[1] << 16) + ((chip_info->prom[3] * dt) >> 7);
+
+ t = 2000 + ((chip_info->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(&indio_dev->dev);
+ 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 struct ms5611_chip_info chip_info_tbl[] = {
+ [MS5611] = {
+ .temp_and_pressure_compensate = ms5611_temp_and_pressure_compensate,
+ },
+ [MS5607] = {
+ .temp_and_pressure_compensate = ms5607_temp_and_pressure_compensate,
+ }
+};
+
+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);
+ st->chip_info = &chip_info_tbl[type];
+ 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 <tduszyns@gmail.com>");
+MODULE_DESCRIPTION("MS5611 core driver");
+MODULE_LICENSE("GPL v2");
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-19 09:56:36 +0000