diff options
Diffstat (limited to 'drivers/iio/gyro/itg3200_core.c')
| -rw-r--r-- | drivers/iio/gyro/itg3200_core.c | 413 |
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, ®val); + if (ret) + return ret; + + *val = (regval & ITG3200_DLPF_CFG_MASK) ? 1000 : 8000; + + ret = itg3200_read_reg_8(indio_dev, + ITG3200_REG_SAMPLE_RATE_DIV, + ®val); + 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"); |