linux/drivers/iio/iio_core.h
Srinivas Pandruvada 9fbfb4b37e IIO: core: Introduce read_raw_multi
This callback is introduced to overcome some limitations of existing
read_raw callback. The functionality of both existing read_raw and
read_raw_multi is similar, both are used to request values from the
device. The current read_raw callback allows only two return values.
The new read_raw_multi allows returning multiple values. Instead of
passing just address of val and val2, it passes length and pointer
to values. Depending on the type and length of passed buffer, iio
client drivers can return multiple values.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2014-04-29 22:05:32 +01:00

74 lines
2.1 KiB
C

/* The industrial I/O core function defs.
*
* Copyright (c) 2008 Jonathan Cameron
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*
* These definitions are meant for use only within the IIO core, not individual
* drivers.
*/
#ifndef _IIO_CORE_H_
#define _IIO_CORE_H_
#include <linux/kernel.h>
#include <linux/device.h>
struct iio_chan_spec;
struct iio_dev;
extern struct device_type iio_device_type;
int __iio_add_chan_devattr(const char *postfix,
struct iio_chan_spec const *chan,
ssize_t (*func)(struct device *dev,
struct device_attribute *attr,
char *buf),
ssize_t (*writefunc)(struct device *dev,
struct device_attribute *attr,
const char *buf,
size_t len),
u64 mask,
enum iio_shared_by shared_by,
struct device *dev,
struct list_head *attr_list);
void iio_free_chan_devattr_list(struct list_head *attr_list);
ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals);
/* Event interface flags */
#define IIO_BUSY_BIT_POS 1
#ifdef CONFIG_IIO_BUFFER
struct poll_table_struct;
unsigned int iio_buffer_poll(struct file *filp,
struct poll_table_struct *wait);
ssize_t iio_buffer_read_first_n_outer(struct file *filp, char __user *buf,
size_t n, loff_t *f_ps);
#define iio_buffer_poll_addr (&iio_buffer_poll)
#define iio_buffer_read_first_n_outer_addr (&iio_buffer_read_first_n_outer)
void iio_disable_all_buffers(struct iio_dev *indio_dev);
void iio_buffer_wakeup_poll(struct iio_dev *indio_dev);
#else
#define iio_buffer_poll_addr NULL
#define iio_buffer_read_first_n_outer_addr NULL
static inline void iio_disable_all_buffers(struct iio_dev *indio_dev) {}
static inline void iio_buffer_wakeup_poll(struct iio_dev *indio_dev) {}
#endif
int iio_device_register_eventset(struct iio_dev *indio_dev);
void iio_device_unregister_eventset(struct iio_dev *indio_dev);
void iio_device_wakeup_eventset(struct iio_dev *indio_dev);
int iio_event_getfd(struct iio_dev *indio_dev);
#endif