| /* |
| * ADIS16080/100 Yaw Rate Gyroscope with SPI driver |
| * |
| * Copyright 2010 Analog Devices Inc. |
| * |
| * Licensed under the GPL-2 or later. |
| */ |
| #include <linux/gpio.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 "../iio.h" |
| #include "../sysfs.h" |
| #include "gyro.h" |
| #include "../adc/adc.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_state - device instance specific data |
| * @us: actual spi_device to write data |
| * @indio_dev: industrial I/O device structure |
| * @buf: transmit or receive buffer |
| * @buf_lock: mutex to protect tx and rx |
| **/ |
| struct adis16080_state { |
| struct spi_device *us; |
| struct iio_dev *indio_dev; |
| struct mutex buf_lock; |
| |
| u8 buf[2] ____cacheline_aligned; |
| }; |
| |
| static int adis16080_spi_write(struct device *dev, |
| u16 val) |
| { |
| int ret; |
| struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| struct adis16080_state *st = iio_dev_get_devdata(indio_dev); |
| |
| mutex_lock(&st->buf_lock); |
| st->buf[0] = val >> 8; |
| st->buf[1] = val; |
| |
| ret = spi_write(st->us, st->buf, 2); |
| mutex_unlock(&st->buf_lock); |
| |
| return ret; |
| } |
| |
| static int adis16080_spi_read(struct device *dev, |
| u16 *val) |
| { |
| int ret; |
| struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| struct adis16080_state *st = iio_dev_get_devdata(indio_dev); |
| |
| mutex_lock(&st->buf_lock); |
| |
| ret = spi_read(st->us, st->buf, 2); |
| |
| if (ret == 0) |
| *val = ((st->buf[0] & 0xF) << 8) | st->buf[1]; |
| mutex_unlock(&st->buf_lock); |
| |
| return ret; |
| } |
| |
| static ssize_t adis16080_read(struct device *dev, |
| struct device_attribute *attr, |
| char *buf) |
| { |
| struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); |
| struct iio_dev *indio_dev = dev_get_drvdata(dev); |
| u16 val = 0; |
| ssize_t ret; |
| |
| /* Take the iio_dev status lock */ |
| mutex_lock(&indio_dev->mlock); |
| ret = adis16080_spi_write(dev, |
| this_attr->address | ADIS16080_DIN_WRITE); |
| if (ret < 0) |
| goto error_ret; |
| ret = adis16080_spi_read(dev, &val); |
| error_ret: |
| mutex_unlock(&indio_dev->mlock); |
| |
| if (ret == 0) |
| return sprintf(buf, "%d\n", val); |
| else |
| return ret; |
| } |
| static IIO_DEV_ATTR_GYRO_Z(adis16080_read, ADIS16080_DIN_GYRO); |
| static IIO_DEVICE_ATTR(temp_raw, S_IRUGO, adis16080_read, NULL, |
| ADIS16080_DIN_TEMP); |
| static IIO_DEV_ATTR_IN_RAW(0, adis16080_read, ADIS16080_DIN_AIN1); |
| static IIO_DEV_ATTR_IN_RAW(1, adis16080_read, ADIS16080_DIN_AIN2); |
| static IIO_CONST_ATTR(name, "adis16080"); |
| |
| static struct attribute *adis16080_attributes[] = { |
| &iio_dev_attr_gyro_z_raw.dev_attr.attr, |
| &iio_dev_attr_temp_raw.dev_attr.attr, |
| &iio_dev_attr_in0_raw.dev_attr.attr, |
| &iio_dev_attr_in1_raw.dev_attr.attr, |
| &iio_const_attr_name.dev_attr.attr, |
| NULL |
| }; |
| |
| static const struct attribute_group adis16080_attribute_group = { |
| .attrs = adis16080_attributes, |
| }; |
| |
| static int __devinit adis16080_probe(struct spi_device *spi) |
| { |
| int ret, regdone = 0; |
| struct adis16080_state *st = kzalloc(sizeof *st, GFP_KERNEL); |
| if (!st) { |
| ret = -ENOMEM; |
| goto error_ret; |
| } |
| /* this is only used for removal purposes */ |
| spi_set_drvdata(spi, st); |
| |
| /* Allocate the comms buffers */ |
| st->us = spi; |
| mutex_init(&st->buf_lock); |
| /* setup the industrialio driver allocated elements */ |
| st->indio_dev = iio_allocate_device(); |
| if (st->indio_dev == NULL) { |
| ret = -ENOMEM; |
| goto error_free_st; |
| } |
| |
| st->indio_dev->dev.parent = &spi->dev; |
| st->indio_dev->attrs = &adis16080_attribute_group; |
| st->indio_dev->dev_data = (void *)(st); |
| st->indio_dev->driver_module = THIS_MODULE; |
| st->indio_dev->modes = INDIO_DIRECT_MODE; |
| |
| ret = iio_device_register(st->indio_dev); |
| if (ret) |
| goto error_free_dev; |
| regdone = 1; |
| |
| return 0; |
| |
| error_free_dev: |
| if (regdone) |
| iio_device_unregister(st->indio_dev); |
| else |
| iio_free_device(st->indio_dev); |
| error_free_st: |
| kfree(st); |
| error_ret: |
| return ret; |
| } |
| |
| /* fixme, confirm ordering in this function */ |
| static int adis16080_remove(struct spi_device *spi) |
| { |
| struct adis16080_state *st = spi_get_drvdata(spi); |
| struct iio_dev *indio_dev = st->indio_dev; |
| |
| iio_device_unregister(indio_dev); |
| kfree(st); |
| |
| return 0; |
| } |
| |
| static struct spi_driver adis16080_driver = { |
| .driver = { |
| .name = "adis16080", |
| .owner = THIS_MODULE, |
| }, |
| .probe = adis16080_probe, |
| .remove = __devexit_p(adis16080_remove), |
| }; |
| |
| static __init int adis16080_init(void) |
| { |
| return spi_register_driver(&adis16080_driver); |
| } |
| module_init(adis16080_init); |
| |
| static __exit void adis16080_exit(void) |
| { |
| spi_unregister_driver(&adis16080_driver); |
| } |
| module_exit(adis16080_exit); |
| |
| MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>"); |
| MODULE_DESCRIPTION("Analog Devices ADIS16080/100 Yaw Rate Gyroscope Driver"); |
| MODULE_LICENSE("GPL v2"); |