erofs-linux/include/linux/uio_driver.h

/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * include/linux/uio_driver.h
 *
 * Copyright(C) 2005, Benedikt Spranger <[email protected]>
 * Copyright(C) 2005, Linutronix GmbH, Thomas Gleixner <[email protected]>
 * Copyright(C) 2006, Hans J. Koch <[email protected]>
 * Copyright(C) 2006, Greg Kroah-Hartman <[email protected]>
 *
 * Userspace IO driver.
 */

#ifndef _UIO_DRIVER_H_
#define _UIO_DRIVER_H_

#include <linux/device.h>
#include <linux/fs.h>
#include <linux/interrupt.h>

struct module;
struct uio_map;

/**
 * struct uio_mem - description of a UIO memory region
 * @name:		name of the memory region for identification
 * @addr:               address of the device's memory rounded to page
 *			size (phys_addr is used since addr can be
 *			logical, virtual, or physical & phys_addr_t
 *			should always be large enough to handle any of
 *			the address types)
 * @dma_addr:		DMA handle set by dma_alloc_coherent, used with
 *			UIO_MEM_DMA_COHERENT only (@addr should be the
 *			void * returned from the same dma_alloc_coherent call)
 * @offs:               offset of device memory within the page
 * @size:		size of IO (multiple of page size)
 * @memtype:		type of memory addr points to
 * @internal_addr:	ioremap-ped version of addr, for driver internal use
 * @dma_device:		device struct that was passed to dma_alloc_coherent,
 *			used with UIO_MEM_DMA_COHERENT only
 * @map:		for use by the UIO core only.
 */
struct uio_mem {
	const char		*name;
	phys_addr_t		addr;
	dma_addr_t		dma_addr;
	unsigned long		offs;
	resource_size_t		size;
	int			memtype;
	void __iomem		*internal_addr;
	struct device		*dma_device;
	struct uio_map		*map;
};

#define MAX_UIO_MAPS	5

struct uio_portio;

/**
 * struct uio_port - description of a UIO port region
 * @name:		name of the port region for identification
 * @start:		start of port region
 * @size:		size of port region
 * @porttype:		type of port (see UIO_PORT_* below)
 * @portio:		for use by the UIO core only.
 */
struct uio_port {
	const char		*name;
	unsigned long		start;
	unsigned long		size;
	int			porttype;
	struct uio_portio	*portio;
};

#define MAX_UIO_PORT_REGIONS	5

struct uio_device {
	struct module           *owner;
	struct device		dev;
	int                     minor;
	atomic_t                event;
	struct fasync_struct    *async_queue;
	wait_queue_head_t       wait;
	struct uio_info         *info;
	struct mutex		info_lock;
	struct kobject          *map_dir;
	struct kobject          *portio_dir;
};

/**
 * struct uio_info - UIO device capabilities
 * @uio_dev:		the UIO device this info belongs to
 * @name:		device name
 * @version:		device driver version
 * @mem:		list of mappable memory regions, size==0 for end of list
 * @port:		list of port regions, size==0 for end of list
 * @irq:		interrupt number or UIO_IRQ_CUSTOM
 * @irq_flags:		flags for request_irq()
 * @priv:		optional private data
 * @handler:		the device's irq handler
 * @mmap_prepare:	mmap_prepare operation for this uio device
 * @open:		open operation for this uio device
 * @release:		release operation for this uio device
 * @irqcontrol:		disable/enable irqs when 0/1 is written to /dev/uioX
 */
struct uio_info {
	struct uio_device	*uio_dev;
	const char		*name;
	const char		*version;
	struct uio_mem		mem[MAX_UIO_MAPS];
	struct uio_port		port[MAX_UIO_PORT_REGIONS];
	long			irq;
	unsigned long		irq_flags;
	void			*priv;
	irqreturn_t (*handler)(int irq, struct uio_info *dev_info);
	int (*mmap_prepare)(struct uio_info *info, struct vm_area_desc *desc);
	int (*open)(struct uio_info *info, struct inode *inode);
	int (*release)(struct uio_info *info, struct inode *inode);
	int (*irqcontrol)(struct uio_info *info, s32 irq_on);
};

extern int __must_check
	__uio_register_device(struct module *owner,
			      struct device *parent,
			      struct uio_info *info);

/* use a define to avoid include chaining to get THIS_MODULE */

/**
 * uio_register_device - register a new userspace IO device
 * @parent:	parent device
 * @info:	UIO device capabilities
 *
 * returns zero on success or a negative error code.
 */
#define uio_register_device(parent, info) \
	__uio_register_device(THIS_MODULE, parent, info)

extern void uio_unregister_device(struct uio_info *info);
extern void uio_event_notify(struct uio_info *info);

extern int __must_check
	__devm_uio_register_device(struct module *owner,
				   struct device *parent,
				   struct uio_info *info);

/* use a define to avoid include chaining to get THIS_MODULE */

/**
 * devm_uio_register_device - Resource managed uio_register_device()
 * @parent:	parent device
 * @info:	UIO device capabilities
 *
 * returns zero on success or a negative error code.
 */
#define devm_uio_register_device(parent, info) \
	__devm_uio_register_device(THIS_MODULE, parent, info)

/* defines for uio_info->irq */
#define UIO_IRQ_CUSTOM	-1
#define UIO_IRQ_NONE	0

/* defines for uio_mem->memtype */
#define UIO_MEM_NONE	0
#define UIO_MEM_PHYS	1
#define UIO_MEM_LOGICAL	2
#define UIO_MEM_VIRTUAL 3
#define UIO_MEM_IOVA	4
/*
 * UIO_MEM_DMA_COHERENT exists for legacy drivers that had been getting by with
 * improperly mapping DMA coherent allocations through the other modes.
 * Do not use in new drivers.
 */
#define UIO_MEM_DMA_COHERENT	5

/* defines for uio_port->porttype */
#define UIO_PORT_NONE	0
#define UIO_PORT_X86	1
#define UIO_PORT_GPIO	2
#define UIO_PORT_OTHER	3

#endif /* _LINUX_UIO_DRIVER_H_ */