summaryrefslogtreecommitdiffstats
path: root/drivers/iio/gyro/itg3200_core.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/iio/gyro/itg3200_core.c')
-rw-r--r--drivers/iio/gyro/itg3200_core.c413
1 files changed, 413 insertions, 0 deletions
diff --git a/drivers/iio/gyro/itg3200_core.c b/drivers/iio/gyro/itg3200_core.c
new file mode 100644
index 000000000..421501584
--- /dev/null
+++ b/drivers/iio/gyro/itg3200_core.c
@@ -0,0 +1,413 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * itg3200_core.c -- support InvenSense ITG3200
+ * Digital 3-Axis Gyroscope driver
+ *
+ * Copyright (c) 2011 Christian Strobel <christian.strobel@iis.fraunhofer.de>
+ * Copyright (c) 2011 Manuel Stahl <manuel.stahl@iis.fraunhofer.de>
+ * Copyright (c) 2012 Thorsten Nowak <thorsten.nowak@iis.fraunhofer.de>
+ *
+ * TODO:
+ * - Support digital low pass filter
+ * - Support power management
+ */
+
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/i2c.h>
+#include <linux/slab.h>
+#include <linux/stat.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/events.h>
+#include <linux/iio/buffer.h>
+
+#include <linux/iio/gyro/itg3200.h>
+
+
+int itg3200_write_reg_8(struct iio_dev *indio_dev,
+ u8 reg_address, u8 val)
+{
+ struct itg3200 *st = iio_priv(indio_dev);
+
+ return i2c_smbus_write_byte_data(st->i2c, 0x80 | reg_address, val);
+}
+
+int itg3200_read_reg_8(struct iio_dev *indio_dev,
+ u8 reg_address, u8 *val)
+{
+ struct itg3200 *st = iio_priv(indio_dev);
+ int ret;
+
+ ret = i2c_smbus_read_byte_data(st->i2c, reg_address);
+ if (ret < 0)
+ return ret;
+ *val = ret;
+ return 0;
+}
+
+static int itg3200_read_reg_s16(struct iio_dev *indio_dev, u8 lower_reg_address,
+ int *val)
+{
+ struct itg3200 *st = iio_priv(indio_dev);
+ struct i2c_client *client = st->i2c;
+ int ret;
+ s16 out;
+
+ struct i2c_msg msg[2] = {
+ {
+ .addr = client->addr,
+ .flags = client->flags,
+ .len = 1,
+ .buf = (char *)&lower_reg_address,
+ },
+ {
+ .addr = client->addr,
+ .flags = client->flags | I2C_M_RD,
+ .len = 2,
+ .buf = (char *)&out,
+ },
+ };
+
+ lower_reg_address |= 0x80;
+ ret = i2c_transfer(client->adapter, msg, 2);
+ be16_to_cpus(&out);
+ *val = out;
+
+ return (ret == 2) ? 0 : ret;
+}
+
+static int itg3200_read_raw(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ int *val, int *val2, long info)
+{
+ int ret = 0;
+ u8 reg;
+ u8 regval;
+
+ switch (info) {
+ case IIO_CHAN_INFO_RAW:
+ reg = (u8)chan->address;
+ ret = itg3200_read_reg_s16(indio_dev, reg, val);
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ *val = 0;
+ if (chan->type == IIO_TEMP)
+ *val2 = 1000000000/280;
+ else
+ *val2 = 1214142; /* (1 / 14,375) * (PI / 180) */
+ return IIO_VAL_INT_PLUS_NANO;
+ case IIO_CHAN_INFO_OFFSET:
+ /* Only the temperature channel has an offset */
+ *val = 23000;
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_DLPF, &regval);
+ if (ret)
+ return ret;
+
+ *val = (regval & ITG3200_DLPF_CFG_MASK) ? 1000 : 8000;
+
+ ret = itg3200_read_reg_8(indio_dev,
+ ITG3200_REG_SAMPLE_RATE_DIV,
+ &regval);
+ if (ret)
+ return ret;
+
+ *val /= regval + 1;
+ return IIO_VAL_INT;
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static int itg3200_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val,
+ int val2,
+ long mask)
+{
+ int ret;
+ u8 t;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ if (val == 0 || val2 != 0)
+ return -EINVAL;
+
+ mutex_lock(&indio_dev->mlock);
+
+ ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_DLPF, &t);
+ if (ret) {
+ mutex_unlock(&indio_dev->mlock);
+ return ret;
+ }
+ t = ((t & ITG3200_DLPF_CFG_MASK) ? 1000u : 8000u) / val - 1;
+
+ ret = itg3200_write_reg_8(indio_dev,
+ ITG3200_REG_SAMPLE_RATE_DIV,
+ t);
+
+ mutex_unlock(&indio_dev->mlock);
+ return ret;
+
+ default:
+ return -EINVAL;
+ }
+}
+
+/*
+ * Reset device and internal registers to the power-up-default settings
+ * Use the gyro clock as reference, as suggested by the datasheet
+ */
+static int itg3200_reset(struct iio_dev *indio_dev)
+{
+ struct itg3200 *st = iio_priv(indio_dev);
+ int ret;
+
+ dev_dbg(&st->i2c->dev, "reset device");
+
+ ret = itg3200_write_reg_8(indio_dev,
+ ITG3200_REG_POWER_MANAGEMENT,
+ ITG3200_RESET);
+ if (ret) {
+ dev_err(&st->i2c->dev, "error resetting device");
+ goto error_ret;
+ }
+
+ /* Wait for PLL (1ms according to datasheet) */
+ udelay(1500);
+
+ ret = itg3200_write_reg_8(indio_dev,
+ ITG3200_REG_IRQ_CONFIG,
+ ITG3200_IRQ_ACTIVE_HIGH |
+ ITG3200_IRQ_PUSH_PULL |
+ ITG3200_IRQ_LATCH_50US_PULSE |
+ ITG3200_IRQ_LATCH_CLEAR_ANY);
+
+ if (ret)
+ dev_err(&st->i2c->dev, "error init device");
+
+error_ret:
+ return ret;
+}
+
+/* itg3200_enable_full_scale() - Disables the digital low pass filter */
+static int itg3200_enable_full_scale(struct iio_dev *indio_dev)
+{
+ u8 val;
+ int ret;
+
+ ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_DLPF, &val);
+ if (ret)
+ goto err_ret;
+
+ val |= ITG3200_DLPF_FS_SEL_2000;
+ return itg3200_write_reg_8(indio_dev, ITG3200_REG_DLPF, val);
+
+err_ret:
+ return ret;
+}
+
+static int itg3200_initial_setup(struct iio_dev *indio_dev)
+{
+ struct itg3200 *st = iio_priv(indio_dev);
+ int ret;
+ u8 val;
+
+ ret = itg3200_reset(indio_dev);
+ if (ret)
+ goto err_ret;
+
+ ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_ADDRESS, &val);
+ if (ret)
+ goto err_ret;
+
+ if (((val >> 1) & 0x3f) != 0x34) {
+ dev_err(&st->i2c->dev, "invalid reg value 0x%02x", val);
+ ret = -ENXIO;
+ goto err_ret;
+ }
+
+ ret = itg3200_enable_full_scale(indio_dev);
+err_ret:
+ return ret;
+}
+
+static const struct iio_mount_matrix *
+itg3200_get_mount_matrix(const struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan)
+{
+ struct itg3200 *data = iio_priv(indio_dev);
+
+ return &data->orientation;
+}
+
+static const struct iio_chan_spec_ext_info itg3200_ext_info[] = {
+ IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, itg3200_get_mount_matrix),
+ { }
+};
+
+#define ITG3200_ST \
+ { .sign = 's', .realbits = 16, .storagebits = 16, .endianness = IIO_BE }
+
+#define ITG3200_GYRO_CHAN(_mod) { \
+ .type = IIO_ANGL_VEL, \
+ .modified = 1, \
+ .channel2 = IIO_MOD_ ## _mod, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+ .address = ITG3200_REG_GYRO_ ## _mod ## OUT_H, \
+ .scan_index = ITG3200_SCAN_GYRO_ ## _mod, \
+ .scan_type = ITG3200_ST, \
+ .ext_info = itg3200_ext_info, \
+}
+
+static const struct iio_chan_spec itg3200_channels[] = {
+ {
+ .type = IIO_TEMP,
+ .channel2 = IIO_NO_MOD,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
+ BIT(IIO_CHAN_INFO_SCALE),
+ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
+ .address = ITG3200_REG_TEMP_OUT_H,
+ .scan_index = ITG3200_SCAN_TEMP,
+ .scan_type = ITG3200_ST,
+ },
+ ITG3200_GYRO_CHAN(X),
+ ITG3200_GYRO_CHAN(Y),
+ ITG3200_GYRO_CHAN(Z),
+ IIO_CHAN_SOFT_TIMESTAMP(ITG3200_SCAN_ELEMENTS),
+};
+
+static const struct iio_info itg3200_info = {
+ .read_raw = &itg3200_read_raw,
+ .write_raw = &itg3200_write_raw,
+};
+
+static const unsigned long itg3200_available_scan_masks[] = { 0xffffffff, 0x0 };
+
+static int itg3200_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ int ret;
+ struct itg3200 *st;
+ struct iio_dev *indio_dev;
+
+ dev_dbg(&client->dev, "probe I2C dev with IRQ %i", client->irq);
+
+ indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ st = iio_priv(indio_dev);
+
+ ret = iio_read_mount_matrix(&client->dev, &st->orientation);
+ if (ret)
+ return ret;
+
+ i2c_set_clientdata(client, indio_dev);
+ st->i2c = client;
+
+ indio_dev->name = client->dev.driver->name;
+ indio_dev->channels = itg3200_channels;
+ indio_dev->num_channels = ARRAY_SIZE(itg3200_channels);
+ indio_dev->available_scan_masks = itg3200_available_scan_masks;
+ indio_dev->info = &itg3200_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ ret = itg3200_buffer_configure(indio_dev);
+ if (ret)
+ return ret;
+
+ if (client->irq) {
+ ret = itg3200_probe_trigger(indio_dev);
+ if (ret)
+ goto error_unconfigure_buffer;
+ }
+
+ ret = itg3200_initial_setup(indio_dev);
+ if (ret)
+ goto error_remove_trigger;
+
+ ret = iio_device_register(indio_dev);
+ if (ret)
+ goto error_remove_trigger;
+
+ return 0;
+
+error_remove_trigger:
+ if (client->irq)
+ itg3200_remove_trigger(indio_dev);
+error_unconfigure_buffer:
+ itg3200_buffer_unconfigure(indio_dev);
+ return ret;
+}
+
+static void itg3200_remove(struct i2c_client *client)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+ iio_device_unregister(indio_dev);
+
+ if (client->irq)
+ itg3200_remove_trigger(indio_dev);
+
+ itg3200_buffer_unconfigure(indio_dev);
+}
+
+static int itg3200_suspend(struct device *dev)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct itg3200 *st = iio_priv(indio_dev);
+
+ dev_dbg(&st->i2c->dev, "suspend device");
+
+ return itg3200_write_reg_8(indio_dev, ITG3200_REG_POWER_MANAGEMENT,
+ ITG3200_SLEEP);
+}
+
+static int itg3200_resume(struct device *dev)
+{
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+
+ return itg3200_initial_setup(indio_dev);
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(itg3200_pm_ops, itg3200_suspend,
+ itg3200_resume);
+
+static const struct i2c_device_id itg3200_id[] = {
+ { "itg3200", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, itg3200_id);
+
+static const struct of_device_id itg3200_of_match[] = {
+ { .compatible = "invensense,itg3200" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, itg3200_of_match);
+
+static struct i2c_driver itg3200_driver = {
+ .driver = {
+ .name = "itg3200",
+ .of_match_table = itg3200_of_match,
+ .pm = pm_sleep_ptr(&itg3200_pm_ops),
+ },
+ .id_table = itg3200_id,
+ .probe = itg3200_probe,
+ .remove = itg3200_remove,
+};
+
+module_i2c_driver(itg3200_driver);
+
+MODULE_AUTHOR("Christian Strobel <christian.strobel@iis.fraunhofer.de>");
+MODULE_DESCRIPTION("ITG3200 Gyroscope I2C driver");
+MODULE_LICENSE("GPL v2");