linux/drivers/iio/iio_core.h
Alexandru Ardelean 8dedcc3eee iio: core: centralize ioctl() calls to the main chardev
The aim of this is to improve a bit the organization of ioctl() calls in
IIO core. Currently the chardev is split across IIO core sub-modules/files.
The main chardev has to be able to handle ioctl() calls, and if we need to
add buffer ioctl() calls, this would complicate things.

The 'industrialio-core.c' file will provide a 'iio_device_ioctl()' which
will iterate over a list of ioctls registered with the IIO device. These
can be event ioctl() or buffer ioctl() calls, or something else.

Each ioctl() handler will have to return a IIO_IOCTL_UNHANDLED code (which
is positive 1), if the ioctl() did not handle the call in any. This
eliminates any potential ambiguities about negative error codes, which
should fail the call altogether.

If any ioctl() returns 0, it was considered that it was serviced
successfully and the loop will exit.

This change also moves the handling of the IIO_GET_EVENT_FD_IOCTL command
inside 'industrialio-event.c', where this is better suited.

This patch is a combination of 2 other patches from an older series:
Patch 1: iio: core: add simple centralized mechanism for ioctl() handlers
  Link: https://lore.kernel.org/linux-iio/20200427131100.50845-6-alexandru.ardelean@analog.com/
Patch 2: iio: core: use new common ioctl() mechanism
  Link: https://lore.kernel.org/linux-iio/20200427131100.50845-7-alexandru.ardelean@analog.com/

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20200924084155.99406-1-alexandru.ardelean@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2020-11-14 15:31:25 +00:00

96 lines
2.7 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/* The industrial I/O core function defs.
*
* Copyright (c) 2008 Jonathan Cameron
*
* 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;
#define IIO_IOCTL_UNHANDLED 1
struct iio_ioctl_handler {
struct list_head entry;
long (*ioctl)(struct iio_dev *indio_dev, struct file *filp,
unsigned int cmd, unsigned long arg);
};
long iio_device_ioctl(struct iio_dev *indio_dev, struct file *filp,
unsigned int cmd, unsigned long arg);
void iio_device_ioctl_handler_register(struct iio_dev *indio_dev,
struct iio_ioctl_handler *h);
void iio_device_ioctl_handler_unregister(struct iio_ioctl_handler *h);
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;
__poll_t iio_buffer_poll(struct file *filp,
struct poll_table_struct *wait);
ssize_t iio_buffer_read_outer(struct file *filp, char __user *buf,
size_t n, loff_t *f_ps);
int iio_buffer_alloc_sysfs_and_mask(struct iio_dev *indio_dev);
void iio_buffer_free_sysfs_and_mask(struct iio_dev *indio_dev);
#define iio_buffer_poll_addr (&iio_buffer_poll)
#define iio_buffer_read_outer_addr (&iio_buffer_read_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_outer_addr NULL
static inline int iio_buffer_alloc_sysfs_and_mask(struct iio_dev *indio_dev)
{
return 0;
}
static inline void iio_buffer_free_sysfs_and_mask(struct iio_dev *indio_dev) {}
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);
struct iio_event_interface;
bool iio_event_enabled(const struct iio_event_interface *ev_int);
#endif