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path: root/drivers/iio/magnetometer/mag3110.c
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-rw-r--r--drivers/iio/magnetometer/mag3110.c652
1 files changed, 652 insertions, 0 deletions
diff --git a/drivers/iio/magnetometer/mag3110.c b/drivers/iio/magnetometer/mag3110.c
new file mode 100644
index 000000000..b870ad803
--- /dev/null
+++ b/drivers/iio/magnetometer/mag3110.c
@@ -0,0 +1,652 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * mag3110.c - Support for Freescale MAG3110 magnetometer sensor
+ *
+ * Copyright (c) 2013 Peter Meerwald <pmeerw@pmeerw.net>
+ *
+ * (7-bit I2C slave address 0x0e)
+ *
+ * TODO: irq, user offset, oversampling, continuous mode
+ */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/delay.h>
+#include <linux/regulator/consumer.h>
+
+#define MAG3110_STATUS 0x00
+#define MAG3110_OUT_X 0x01 /* MSB first */
+#define MAG3110_OUT_Y 0x03
+#define MAG3110_OUT_Z 0x05
+#define MAG3110_WHO_AM_I 0x07
+#define MAG3110_SYSMOD 0x08
+#define MAG3110_OFF_X 0x09 /* MSB first */
+#define MAG3110_OFF_Y 0x0b
+#define MAG3110_OFF_Z 0x0d
+#define MAG3110_DIE_TEMP 0x0f
+#define MAG3110_CTRL_REG1 0x10
+#define MAG3110_CTRL_REG2 0x11
+
+#define MAG3110_STATUS_DRDY (BIT(2) | BIT(1) | BIT(0))
+
+#define MAG3110_CTRL_DR_MASK (BIT(7) | BIT(6) | BIT(5))
+#define MAG3110_CTRL_DR_SHIFT 5
+#define MAG3110_CTRL_DR_DEFAULT 0
+
+#define MAG3110_SYSMOD_MODE_MASK GENMASK(1, 0)
+
+#define MAG3110_CTRL_TM BIT(1) /* trigger single measurement */
+#define MAG3110_CTRL_AC BIT(0) /* continuous measurements */
+
+#define MAG3110_CTRL_AUTO_MRST_EN BIT(7) /* magnetic auto-reset */
+#define MAG3110_CTRL_RAW BIT(5) /* measurements not user-offset corrected */
+
+#define MAG3110_DEVICE_ID 0xc4
+
+/* Each client has this additional data */
+struct mag3110_data {
+ struct i2c_client *client;
+ struct mutex lock;
+ u8 ctrl_reg1;
+ int sleep_val;
+ struct regulator *vdd_reg;
+ struct regulator *vddio_reg;
+ /* Ensure natural alignment of timestamp */
+ struct {
+ __be16 channels[3];
+ u8 temperature;
+ s64 ts __aligned(8);
+ } scan;
+};
+
+static int mag3110_request(struct mag3110_data *data)
+{
+ int ret, tries = 150;
+
+ if ((data->ctrl_reg1 & MAG3110_CTRL_AC) == 0) {
+ /* trigger measurement */
+ ret = i2c_smbus_write_byte_data(data->client, MAG3110_CTRL_REG1,
+ data->ctrl_reg1 | MAG3110_CTRL_TM);
+ if (ret < 0)
+ return ret;
+ }
+
+ while (tries-- > 0) {
+ ret = i2c_smbus_read_byte_data(data->client, MAG3110_STATUS);
+ if (ret < 0)
+ return ret;
+ /* wait for data ready */
+ if ((ret & MAG3110_STATUS_DRDY) == MAG3110_STATUS_DRDY)
+ break;
+
+ if (data->sleep_val <= 20)
+ usleep_range(data->sleep_val * 250, data->sleep_val * 500);
+ else
+ msleep(20);
+ }
+
+ if (tries < 0) {
+ dev_err(&data->client->dev, "data not ready\n");
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static int mag3110_read(struct mag3110_data *data, __be16 buf[3])
+{
+ int ret;
+
+ mutex_lock(&data->lock);
+ ret = mag3110_request(data);
+ if (ret < 0) {
+ mutex_unlock(&data->lock);
+ return ret;
+ }
+ ret = i2c_smbus_read_i2c_block_data(data->client,
+ MAG3110_OUT_X, 3 * sizeof(__be16), (u8 *) buf);
+ mutex_unlock(&data->lock);
+
+ return ret;
+}
+
+static ssize_t mag3110_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 mag3110_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 const int mag3110_samp_freq[8][2] = {
+ {80, 0}, {40, 0}, {20, 0}, {10, 0}, {5, 0}, {2, 500000},
+ {1, 250000}, {0, 625000}
+};
+
+static ssize_t mag3110_show_samp_freq_avail(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return mag3110_show_int_plus_micros(buf, mag3110_samp_freq, 8);
+}
+
+static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(mag3110_show_samp_freq_avail);
+
+static int mag3110_get_samp_freq_index(struct mag3110_data *data,
+ int val, int val2)
+{
+ return mag3110_get_int_plus_micros_index(mag3110_samp_freq, 8, val,
+ val2);
+}
+
+static int mag3110_calculate_sleep(struct mag3110_data *data)
+{
+ int ret, i = data->ctrl_reg1 >> MAG3110_CTRL_DR_SHIFT;
+
+ if (mag3110_samp_freq[i][0] > 0)
+ ret = 1000 / mag3110_samp_freq[i][0];
+ else
+ ret = 1000;
+
+ return ret == 0 ? 1 : ret;
+}
+
+static int mag3110_standby(struct mag3110_data *data)
+{
+ return i2c_smbus_write_byte_data(data->client, MAG3110_CTRL_REG1,
+ data->ctrl_reg1 & ~MAG3110_CTRL_AC);
+}
+
+static int mag3110_wait_standby(struct mag3110_data *data)
+{
+ int ret, tries = 30;
+
+ /*
+ * Takes up to 1/ODR to come out of active mode into stby
+ * Longest expected period is 12.5seconds.
+ * We'll sleep for 500ms between checks
+ */
+ while (tries-- > 0) {
+ ret = i2c_smbus_read_byte_data(data->client, MAG3110_SYSMOD);
+ if (ret < 0) {
+ dev_err(&data->client->dev, "i2c error\n");
+ return ret;
+ }
+ /* wait for standby */
+ if ((ret & MAG3110_SYSMOD_MODE_MASK) == 0)
+ break;
+
+ msleep_interruptible(500);
+ }
+
+ if (tries < 0) {
+ dev_err(&data->client->dev, "device not entering standby mode\n");
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static int mag3110_active(struct mag3110_data *data)
+{
+ return i2c_smbus_write_byte_data(data->client, MAG3110_CTRL_REG1,
+ data->ctrl_reg1);
+}
+
+/* returns >0 if active, 0 if in standby and <0 on error */
+static int mag3110_is_active(struct mag3110_data *data)
+{
+ int reg;
+
+ reg = i2c_smbus_read_byte_data(data->client, MAG3110_CTRL_REG1);
+ if (reg < 0)
+ return reg;
+
+ return reg & MAG3110_CTRL_AC;
+}
+
+static int mag3110_change_config(struct mag3110_data *data, u8 reg, u8 val)
+{
+ int ret;
+ int is_active;
+
+ mutex_lock(&data->lock);
+
+ is_active = mag3110_is_active(data);
+ if (is_active < 0) {
+ ret = is_active;
+ goto fail;
+ }
+
+ /* config can only be changed when in standby */
+ if (is_active > 0) {
+ ret = mag3110_standby(data);
+ if (ret < 0)
+ goto fail;
+ }
+
+ /*
+ * After coming out of active we must wait for the part
+ * to transition to STBY. This can take up to 1 /ODR to occur
+ */
+ ret = mag3110_wait_standby(data);
+ if (ret < 0)
+ goto fail;
+
+ ret = i2c_smbus_write_byte_data(data->client, reg, val);
+ if (ret < 0)
+ goto fail;
+
+ if (is_active > 0) {
+ ret = mag3110_active(data);
+ if (ret < 0)
+ goto fail;
+ }
+
+ ret = 0;
+fail:
+ mutex_unlock(&data->lock);
+
+ return ret;
+}
+
+static int mag3110_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct mag3110_data *data = iio_priv(indio_dev);
+ __be16 buffer[3];
+ int i, ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ ret = iio_device_claim_direct_mode(indio_dev);
+ if (ret)
+ return ret;
+
+ switch (chan->type) {
+ case IIO_MAGN: /* in 0.1 uT / LSB */
+ ret = mag3110_read(data, buffer);
+ if (ret < 0)
+ goto release;
+ *val = sign_extend32(
+ be16_to_cpu(buffer[chan->scan_index]),
+ chan->scan_type.realbits - 1);
+ ret = IIO_VAL_INT;
+ break;
+ case IIO_TEMP: /* in 1 C / LSB */
+ mutex_lock(&data->lock);
+ ret = mag3110_request(data);
+ if (ret < 0) {
+ mutex_unlock(&data->lock);
+ goto release;
+ }
+ ret = i2c_smbus_read_byte_data(data->client,
+ MAG3110_DIE_TEMP);
+ mutex_unlock(&data->lock);
+ if (ret < 0)
+ goto release;
+ *val = sign_extend32(ret,
+ chan->scan_type.realbits - 1);
+ ret = IIO_VAL_INT;
+ break;
+ default:
+ ret = -EINVAL;
+ }
+release:
+ iio_device_release_direct_mode(indio_dev);
+ return ret;
+
+ case IIO_CHAN_INFO_SCALE:
+ switch (chan->type) {
+ case IIO_MAGN:
+ *val = 0;
+ *val2 = 1000;
+ return IIO_VAL_INT_PLUS_MICRO;
+ case IIO_TEMP:
+ *val = 1000;
+ return IIO_VAL_INT;
+ default:
+ return -EINVAL;
+ }
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ i = data->ctrl_reg1 >> MAG3110_CTRL_DR_SHIFT;
+ *val = mag3110_samp_freq[i][0];
+ *val2 = mag3110_samp_freq[i][1];
+ return IIO_VAL_INT_PLUS_MICRO;
+ case IIO_CHAN_INFO_CALIBBIAS:
+ ret = i2c_smbus_read_word_swapped(data->client,
+ MAG3110_OFF_X + 2 * chan->scan_index);
+ if (ret < 0)
+ return ret;
+ *val = sign_extend32(ret >> 1, 14);
+ return IIO_VAL_INT;
+ }
+ return -EINVAL;
+}
+
+static int mag3110_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct mag3110_data *data = iio_priv(indio_dev);
+ int rate, ret;
+
+ ret = iio_device_claim_direct_mode(indio_dev);
+ if (ret)
+ return ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ rate = mag3110_get_samp_freq_index(data, val, val2);
+ if (rate < 0) {
+ ret = -EINVAL;
+ break;
+ }
+ data->ctrl_reg1 &= 0xff & ~MAG3110_CTRL_DR_MASK
+ & ~MAG3110_CTRL_AC;
+ data->ctrl_reg1 |= rate << MAG3110_CTRL_DR_SHIFT;
+ data->sleep_val = mag3110_calculate_sleep(data);
+ if (data->sleep_val < 40)
+ data->ctrl_reg1 |= MAG3110_CTRL_AC;
+
+ ret = mag3110_change_config(data, MAG3110_CTRL_REG1,
+ data->ctrl_reg1);
+ break;
+ case IIO_CHAN_INFO_CALIBBIAS:
+ if (val < -10000 || val > 10000) {
+ ret = -EINVAL;
+ break;
+ }
+ ret = i2c_smbus_write_word_swapped(data->client,
+ MAG3110_OFF_X + 2 * chan->scan_index, val << 1);
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+ iio_device_release_direct_mode(indio_dev);
+ return ret;
+}
+
+static irqreturn_t mag3110_trigger_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct mag3110_data *data = iio_priv(indio_dev);
+ int ret;
+
+ ret = mag3110_read(data, data->scan.channels);
+ if (ret < 0)
+ goto done;
+
+ if (test_bit(3, indio_dev->active_scan_mask)) {
+ ret = i2c_smbus_read_byte_data(data->client,
+ MAG3110_DIE_TEMP);
+ if (ret < 0)
+ goto done;
+ data->scan.temperature = ret;
+ }
+
+ iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
+ iio_get_time_ns(indio_dev));
+
+done:
+ iio_trigger_notify_done(indio_dev->trig);
+ return IRQ_HANDLED;
+}
+
+#define MAG3110_CHANNEL(axis, idx) { \
+ .type = IIO_MAGN, \
+ .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), \
+ .scan_index = idx, \
+ .scan_type = { \
+ .sign = 's', \
+ .realbits = 16, \
+ .storagebits = 16, \
+ .endianness = IIO_BE, \
+ }, \
+}
+
+static const struct iio_chan_spec mag3110_channels[] = {
+ MAG3110_CHANNEL(X, 0),
+ MAG3110_CHANNEL(Y, 1),
+ MAG3110_CHANNEL(Z, 2),
+ {
+ .type = IIO_TEMP,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE),
+ .scan_index = 3,
+ .scan_type = {
+ .sign = 's',
+ .realbits = 8,
+ .storagebits = 8,
+ },
+ },
+ IIO_CHAN_SOFT_TIMESTAMP(4),
+};
+
+static struct attribute *mag3110_attributes[] = {
+ &iio_dev_attr_sampling_frequency_available.dev_attr.attr,
+ NULL
+};
+
+static const struct attribute_group mag3110_group = {
+ .attrs = mag3110_attributes,
+};
+
+static const struct iio_info mag3110_info = {
+ .attrs = &mag3110_group,
+ .read_raw = &mag3110_read_raw,
+ .write_raw = &mag3110_write_raw,
+};
+
+static const unsigned long mag3110_scan_masks[] = {0x7, 0xf, 0};
+
+static int mag3110_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct mag3110_data *data;
+ struct iio_dev *indio_dev;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ data = iio_priv(indio_dev);
+
+ data->vdd_reg = devm_regulator_get(&client->dev, "vdd");
+ if (IS_ERR(data->vdd_reg))
+ return dev_err_probe(&client->dev, PTR_ERR(data->vdd_reg),
+ "failed to get VDD regulator!\n");
+
+ data->vddio_reg = devm_regulator_get(&client->dev, "vddio");
+ if (IS_ERR(data->vddio_reg))
+ return dev_err_probe(&client->dev, PTR_ERR(data->vddio_reg),
+ "failed to get VDDIO regulator!\n");
+
+ ret = regulator_enable(data->vdd_reg);
+ if (ret) {
+ dev_err(&client->dev, "failed to enable VDD regulator!\n");
+ return ret;
+ }
+
+ ret = regulator_enable(data->vddio_reg);
+ if (ret) {
+ dev_err(&client->dev, "failed to enable VDDIO regulator!\n");
+ goto disable_regulator_vdd;
+ }
+
+ ret = i2c_smbus_read_byte_data(client, MAG3110_WHO_AM_I);
+ if (ret < 0)
+ goto disable_regulators;
+ if (ret != MAG3110_DEVICE_ID) {
+ ret = -ENODEV;
+ goto disable_regulators;
+ }
+
+ data->client = client;
+ mutex_init(&data->lock);
+
+ i2c_set_clientdata(client, indio_dev);
+ indio_dev->info = &mag3110_info;
+ indio_dev->name = id->name;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->channels = mag3110_channels;
+ indio_dev->num_channels = ARRAY_SIZE(mag3110_channels);
+ indio_dev->available_scan_masks = mag3110_scan_masks;
+
+ data->ctrl_reg1 = MAG3110_CTRL_DR_DEFAULT << MAG3110_CTRL_DR_SHIFT;
+ data->sleep_val = mag3110_calculate_sleep(data);
+ if (data->sleep_val < 40)
+ data->ctrl_reg1 |= MAG3110_CTRL_AC;
+
+ ret = mag3110_change_config(data, MAG3110_CTRL_REG1, data->ctrl_reg1);
+ if (ret < 0)
+ goto disable_regulators;
+
+ ret = i2c_smbus_write_byte_data(client, MAG3110_CTRL_REG2,
+ MAG3110_CTRL_AUTO_MRST_EN);
+ if (ret < 0)
+ goto standby_on_error;
+
+ ret = iio_triggered_buffer_setup(indio_dev, NULL,
+ mag3110_trigger_handler, NULL);
+ if (ret < 0)
+ goto standby_on_error;
+
+ ret = iio_device_register(indio_dev);
+ if (ret < 0)
+ goto buffer_cleanup;
+ return 0;
+
+buffer_cleanup:
+ iio_triggered_buffer_cleanup(indio_dev);
+standby_on_error:
+ mag3110_standby(iio_priv(indio_dev));
+disable_regulators:
+ regulator_disable(data->vddio_reg);
+disable_regulator_vdd:
+ regulator_disable(data->vdd_reg);
+
+ return ret;
+}
+
+static void mag3110_remove(struct i2c_client *client)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(client);
+ struct mag3110_data *data = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+ iio_triggered_buffer_cleanup(indio_dev);
+ mag3110_standby(iio_priv(indio_dev));
+ regulator_disable(data->vddio_reg);
+ regulator_disable(data->vdd_reg);
+}
+
+static int mag3110_suspend(struct device *dev)
+{
+ struct mag3110_data *data = iio_priv(i2c_get_clientdata(
+ to_i2c_client(dev)));
+ int ret;
+
+ ret = mag3110_standby(iio_priv(i2c_get_clientdata(
+ to_i2c_client(dev))));
+ if (ret)
+ return ret;
+
+ ret = regulator_disable(data->vddio_reg);
+ if (ret) {
+ dev_err(dev, "failed to disable VDDIO regulator\n");
+ return ret;
+ }
+
+ ret = regulator_disable(data->vdd_reg);
+ if (ret) {
+ dev_err(dev, "failed to disable VDD regulator\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int mag3110_resume(struct device *dev)
+{
+ struct mag3110_data *data = iio_priv(i2c_get_clientdata(
+ to_i2c_client(dev)));
+ int ret;
+
+ ret = regulator_enable(data->vdd_reg);
+ if (ret) {
+ dev_err(dev, "failed to enable VDD regulator\n");
+ return ret;
+ }
+
+ ret = regulator_enable(data->vddio_reg);
+ if (ret) {
+ dev_err(dev, "failed to enable VDDIO regulator\n");
+ regulator_disable(data->vdd_reg);
+ return ret;
+ }
+
+ return i2c_smbus_write_byte_data(data->client, MAG3110_CTRL_REG1,
+ data->ctrl_reg1);
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(mag3110_pm_ops, mag3110_suspend,
+ mag3110_resume);
+
+static const struct i2c_device_id mag3110_id[] = {
+ { "mag3110", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, mag3110_id);
+
+static const struct of_device_id mag3110_of_match[] = {
+ { .compatible = "fsl,mag3110" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, mag3110_of_match);
+
+static struct i2c_driver mag3110_driver = {
+ .driver = {
+ .name = "mag3110",
+ .of_match_table = mag3110_of_match,
+ .pm = pm_sleep_ptr(&mag3110_pm_ops),
+ },
+ .probe = mag3110_probe,
+ .remove = mag3110_remove,
+ .id_table = mag3110_id,
+};
+module_i2c_driver(mag3110_driver);
+
+MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
+MODULE_DESCRIPTION("Freescale MAG3110 magnetometer driver");
+MODULE_LICENSE("GPL");
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-24 11:09:16 +0000