diff options
Diffstat (limited to 'kernel/drivers/staging/iio/gyro/adis16060_core.c')
| -rw-r--r-- | kernel/drivers/staging/iio/gyro/adis16060_core.c | 246 |
1 files changed, 246 insertions, 0 deletions
diff --git a/kernel/drivers/staging/iio/gyro/adis16060_core.c b/kernel/drivers/staging/iio/gyro/adis16060_core.c new file mode 100644 index 000000000..4c5869dd8 --- /dev/null +++ b/kernel/drivers/staging/iio/gyro/adis16060_core.c @@ -0,0 +1,246 @@ +/* + * ADIS16060 Wide Bandwidth Yaw Rate Gyroscope with SPI driver + * + * Copyright 2010 Analog Devices Inc. + * + * Licensed under the GPL-2 or later. + */ + +#include <linux/module.h> +#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/iio/iio.h> +#include <linux/iio/sysfs.h> + +#define ADIS16060_GYRO 0x20 /* Measure Angular Rate (Gyro) */ +#define ADIS16060_TEMP_OUT 0x10 /* Measure Temperature */ +#define ADIS16060_AIN2 0x80 /* Measure AIN2 */ +#define ADIS16060_AIN1 0x40 /* Measure AIN1 */ + +/** + * struct adis16060_state - device instance specific data + * @us_w: actual spi_device to write config + * @us_r: actual spi_device to read back data + * @buf: transmit or receive buffer + * @buf_lock: mutex to protect tx and rx + **/ +struct adis16060_state { + struct spi_device *us_w; + struct spi_device *us_r; + struct mutex buf_lock; + + u8 buf[3] ____cacheline_aligned; +}; + +static struct iio_dev *adis16060_iio_dev; + +static int adis16060_spi_write(struct iio_dev *indio_dev, u8 val) +{ + int ret; + struct adis16060_state *st = iio_priv(indio_dev); + + mutex_lock(&st->buf_lock); + st->buf[2] = val; /* The last 8 bits clocked in are latched */ + ret = spi_write(st->us_w, st->buf, 3); + mutex_unlock(&st->buf_lock); + + return ret; +} + +static int adis16060_spi_read(struct iio_dev *indio_dev, u16 *val) +{ + int ret; + struct adis16060_state *st = iio_priv(indio_dev); + + mutex_lock(&st->buf_lock); + + ret = spi_read(st->us_r, st->buf, 3); + + /* The internal successive approximation ADC begins the + * conversion process on the falling edge of MSEL1 and + * starts to place data MSB first on the DOUT line at + * the 6th falling edge of SCLK + */ + if (ret == 0) + *val = ((st->buf[0] & 0x3) << 12) | + (st->buf[1] << 4) | + ((st->buf[2] >> 4) & 0xF); + mutex_unlock(&st->buf_lock); + + return ret; +} + +static int adis16060_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, + long mask) +{ + u16 tval = 0; + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + /* Take the iio_dev status lock */ + mutex_lock(&indio_dev->mlock); + ret = adis16060_spi_write(indio_dev, chan->address); + if (ret < 0) { + mutex_unlock(&indio_dev->mlock); + return ret; + } + ret = adis16060_spi_read(indio_dev, &tval); + mutex_unlock(&indio_dev->mlock); + *val = tval; + return IIO_VAL_INT; + case IIO_CHAN_INFO_OFFSET: + *val = -7; + *val2 = 461117; + return IIO_VAL_INT_PLUS_MICRO; + case IIO_CHAN_INFO_SCALE: + *val = 0; + *val2 = 34000; + return IIO_VAL_INT_PLUS_MICRO; + } + + return -EINVAL; +} + +static const struct iio_info adis16060_info = { + .read_raw = &adis16060_read_raw, + .driver_module = THIS_MODULE, +}; + +static const struct iio_chan_spec adis16060_channels[] = { + { + .type = IIO_ANGL_VEL, + .modified = 1, + .channel2 = IIO_MOD_Z, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .address = ADIS16060_GYRO, + }, { + .type = IIO_VOLTAGE, + .indexed = 1, + .channel = 0, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .address = ADIS16060_AIN1, + }, { + .type = IIO_VOLTAGE, + .indexed = 1, + .channel = 1, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .address = ADIS16060_AIN2, + }, { + .type = IIO_TEMP, + .indexed = 1, + .channel = 0, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_OFFSET) | BIT(IIO_CHAN_INFO_SCALE), + .address = ADIS16060_TEMP_OUT, + } +}; + +static int adis16060_r_probe(struct spi_device *spi) +{ + int ret; + struct adis16060_state *st; + struct iio_dev *indio_dev; + + /* setup the industrialio driver allocated elements */ + indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); + if (!indio_dev) + return -ENOMEM; + /* this is only used for removal purposes */ + spi_set_drvdata(spi, indio_dev); + st = iio_priv(indio_dev); + st->us_r = spi; + mutex_init(&st->buf_lock); + + indio_dev->name = spi->dev.driver->name; + indio_dev->dev.parent = &spi->dev; + indio_dev->info = &adis16060_info; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->channels = adis16060_channels; + indio_dev->num_channels = ARRAY_SIZE(adis16060_channels); + + ret = devm_iio_device_register(&spi->dev, indio_dev); + if (ret) + return ret; + + adis16060_iio_dev = indio_dev; + return 0; +} + +static int adis16060_w_probe(struct spi_device *spi) +{ + int ret; + struct iio_dev *indio_dev = adis16060_iio_dev; + struct adis16060_state *st; + + if (!indio_dev) { + ret = -ENODEV; + goto error_ret; + } + st = iio_priv(indio_dev); + spi_set_drvdata(spi, indio_dev); + st->us_w = spi; + return 0; + +error_ret: + return ret; +} + +static int adis16060_w_remove(struct spi_device *spi) +{ + return 0; +} + +static struct spi_driver adis16060_r_driver = { + .driver = { + .name = "adis16060_r", + .owner = THIS_MODULE, + }, + .probe = adis16060_r_probe, +}; + +static struct spi_driver adis16060_w_driver = { + .driver = { + .name = "adis16060_w", + .owner = THIS_MODULE, + }, + .probe = adis16060_w_probe, + .remove = adis16060_w_remove, +}; + +static __init int adis16060_init(void) +{ + int ret; + + ret = spi_register_driver(&adis16060_r_driver); + if (ret < 0) + return ret; + + ret = spi_register_driver(&adis16060_w_driver); + if (ret < 0) { + spi_unregister_driver(&adis16060_r_driver); + return ret; + } + + return 0; +} +module_init(adis16060_init); + +static __exit void adis16060_exit(void) +{ + spi_unregister_driver(&adis16060_w_driver); + spi_unregister_driver(&adis16060_r_driver); +} +module_exit(adis16060_exit); + +MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>"); +MODULE_DESCRIPTION("Analog Devices ADIS16060 Yaw Rate Gyroscope Driver"); +MODULE_LICENSE("GPL v2"); |