diff options
Diffstat (limited to 'drivers/iio/gyro/adis16080.c')
| -rw-r--r-- | drivers/iio/gyro/adis16080.c | 259 |
1 files changed, 259 insertions, 0 deletions
diff --git a/drivers/iio/gyro/adis16080.c b/drivers/iio/gyro/adis16080.c new file mode 100644 index 000000000000..1861287911f1 --- /dev/null +++ b/drivers/iio/gyro/adis16080.c @@ -0,0 +1,259 @@ +/* + * ADIS16080/100 Yaw Rate Gyroscope with SPI driver + * + * Copyright 2010 Analog Devices Inc. + * + * Licensed under the GPL-2 or later. + */ +#include <linux/delay.h> +#include <linux/mutex.h> +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/spi/spi.h> +#include <linux/slab.h> +#include <linux/sysfs.h> +#include <linux/module.h> + +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> + +#define ADIS16080_DIN_GYRO (0 << 10) /* Gyroscope output */ +#define ADIS16080_DIN_TEMP (1 << 10) /* Temperature output */ +#define ADIS16080_DIN_AIN1 (2 << 10) +#define ADIS16080_DIN_AIN2 (3 << 10) + +/* + * 1: Write contents on DIN to control register. + * 0: No changes to control register. + */ + +#define ADIS16080_DIN_WRITE (1 << 15) + +struct adis16080_chip_info { + int scale_val; + int scale_val2; +}; + +/** + * struct adis16080_state - device instance specific data + * @us: actual spi_device to write data + * @info: chip specific parameters + * @buf: transmit or receive buffer + **/ +struct adis16080_state { + struct spi_device *us; + const struct adis16080_chip_info *info; + + __be16 buf ____cacheline_aligned; +}; + +static int adis16080_read_sample(struct iio_dev *indio_dev, + u16 addr, int *val) +{ + struct adis16080_state *st = iio_priv(indio_dev); + struct spi_message m; + int ret; + struct spi_transfer t[] = { + { + .tx_buf = &st->buf, + .len = 2, + .cs_change = 1, + }, { + .rx_buf = &st->buf, + .len = 2, + }, + }; + + st->buf = cpu_to_be16(addr | ADIS16080_DIN_WRITE); + + spi_message_init(&m); + spi_message_add_tail(&t[0], &m); + spi_message_add_tail(&t[1], &m); + + ret = spi_sync(st->us, &m); + if (ret == 0) + *val = sign_extend32(be16_to_cpu(st->buf), 11); + + return ret; +} + +static int adis16080_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, + int *val2, + long mask) +{ + struct adis16080_state *st = iio_priv(indio_dev); + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + mutex_lock(&indio_dev->mlock); + ret = adis16080_read_sample(indio_dev, chan->address, val); + mutex_unlock(&indio_dev->mlock); + return ret ? ret : IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + switch (chan->type) { + case IIO_ANGL_VEL: + *val = st->info->scale_val; + *val2 = st->info->scale_val2; + return IIO_VAL_FRACTIONAL; + case IIO_VOLTAGE: + /* VREF = 5V, 12 bits */ + *val = 5000; + *val2 = 12; + return IIO_VAL_FRACTIONAL_LOG2; + case IIO_TEMP: + /* 85 C = 585, 25 C = 0 */ + *val = 85000 - 25000; + *val2 = 585; + return IIO_VAL_FRACTIONAL; + default: + return -EINVAL; + } + case IIO_CHAN_INFO_OFFSET: + switch (chan->type) { + case IIO_VOLTAGE: + /* 2.5 V = 0 */ + *val = 2048; + return IIO_VAL_INT; + case IIO_TEMP: + /* 85 C = 585, 25 C = 0 */ + *val = DIV_ROUND_CLOSEST(25 * 585, 85 - 25); + return IIO_VAL_INT; + default: + return -EINVAL; + } + default: + break; + } + + return -EINVAL; +} + +static const struct iio_chan_spec adis16080_channels[] = { + { + .type = IIO_ANGL_VEL, + .modified = 1, + .channel2 = IIO_MOD_Z, + .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | + IIO_CHAN_INFO_SCALE_SEPARATE_BIT, + .address = ADIS16080_DIN_GYRO, + }, { + .type = IIO_VOLTAGE, + .indexed = 1, + .channel = 0, + .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | + IIO_CHAN_INFO_SCALE_SEPARATE_BIT | + IIO_CHAN_INFO_OFFSET_SEPARATE_BIT, + .address = ADIS16080_DIN_AIN1, + }, { + .type = IIO_VOLTAGE, + .indexed = 1, + .channel = 1, + .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | + IIO_CHAN_INFO_SCALE_SEPARATE_BIT | + IIO_CHAN_INFO_OFFSET_SEPARATE_BIT, + .address = ADIS16080_DIN_AIN2, + }, { + .type = IIO_TEMP, + .indexed = 1, + .channel = 0, + .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | + IIO_CHAN_INFO_SCALE_SEPARATE_BIT | + IIO_CHAN_INFO_OFFSET_SEPARATE_BIT, + .address = ADIS16080_DIN_TEMP, + } +}; + +static const struct iio_info adis16080_info = { + .read_raw = &adis16080_read_raw, + .driver_module = THIS_MODULE, +}; + +enum { + ID_ADIS16080, + ID_ADIS16100, +}; + +static const struct adis16080_chip_info adis16080_chip_info[] = { + [ID_ADIS16080] = { + /* 80 degree = 819, 819 rad = 46925 degree */ + .scale_val = 80, + .scale_val2 = 46925, + }, + [ID_ADIS16100] = { + /* 300 degree = 1230, 1230 rad = 70474 degree */ + .scale_val = 300, + .scale_val2 = 70474, + }, +}; + +static int adis16080_probe(struct spi_device *spi) +{ + const struct spi_device_id *id = spi_get_device_id(spi); + int ret; + struct adis16080_state *st; + struct iio_dev *indio_dev; + + /* setup the industrialio driver allocated elements */ + indio_dev = iio_device_alloc(sizeof(*st)); + if (indio_dev == NULL) { + ret = -ENOMEM; + goto error_ret; + } + st = iio_priv(indio_dev); + /* this is only used for removal purposes */ + spi_set_drvdata(spi, indio_dev); + + /* Allocate the comms buffers */ + st->us = spi; + st->info = &adis16080_chip_info[id->driver_data]; + + indio_dev->name = spi->dev.driver->name; + indio_dev->channels = adis16080_channels; + indio_dev->num_channels = ARRAY_SIZE(adis16080_channels); + indio_dev->dev.parent = &spi->dev; + indio_dev->info = &adis16080_info; + indio_dev->modes = INDIO_DIRECT_MODE; + + ret = iio_device_register(indio_dev); + if (ret) + goto error_free_dev; + return 0; + +error_free_dev: + iio_device_free(indio_dev); +error_ret: + return ret; +} + +static int adis16080_remove(struct spi_device *spi) +{ + iio_device_unregister(spi_get_drvdata(spi)); + iio_device_free(spi_get_drvdata(spi)); + + return 0; +} + +static const struct spi_device_id adis16080_ids[] = { + { "adis16080", ID_ADIS16080 }, + { "adis16100", ID_ADIS16100 }, + {}, +}; +MODULE_DEVICE_TABLE(spi, adis16080_ids); + +static struct spi_driver adis16080_driver = { + .driver = { + .name = "adis16080", + .owner = THIS_MODULE, + }, + .probe = adis16080_probe, + .remove = adis16080_remove, + .id_table = adis16080_ids, +}; +module_spi_driver(adis16080_driver); + +MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>"); +MODULE_DESCRIPTION("Analog Devices ADIS16080/100 Yaw Rate Gyroscope Driver"); +MODULE_LICENSE("GPL v2"); |