1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * include/linux/uio_driver.h
4  *
5  * Copyright(C) 2005, Benedikt Spranger <b.spranger@linutronix.de>
6  * Copyright(C) 2005, Thomas Gleixner <tglx@linutronix.de>
7  * Copyright(C) 2006, Hans J. Koch <hjk@hansjkoch.de>
8  * Copyright(C) 2006, Greg Kroah-Hartman <greg@kroah.com>
9  *
10  * Userspace IO driver.
11  */
12 
13 #ifndef _UIO_DRIVER_H_
14 #define _UIO_DRIVER_H_
15 
16 #include <linux/device.h>
17 #include <linux/fs.h>
18 #include <linux/interrupt.h>
19 
20 struct module;
21 struct uio_map;
22 
23 /**
24  * struct uio_mem - description of a UIO memory region
25  * @name:		name of the memory region for identification
26  * @addr:               address of the device's memory rounded to page
27  *			size (phys_addr is used since addr can be
28  *			logical, virtual, or physical & phys_addr_t
29  *			should always be large enough to handle any of
30  *			the address types)
31  * @dma_addr:		DMA handle set by dma_alloc_coherent, used with
32  *			UIO_MEM_DMA_COHERENT only (@addr should be the
33  *			void * returned from the same dma_alloc_coherent call)
34  * @offs:               offset of device memory within the page
35  * @size:		size of IO (multiple of page size)
36  * @memtype:		type of memory addr points to
37  * @internal_addr:	ioremap-ped version of addr, for driver internal use
38  * @dma_device:		device struct that was passed to dma_alloc_coherent,
39  *			used with UIO_MEM_DMA_COHERENT only
40  * @map:		for use by the UIO core only.
41  */
42 struct uio_mem {
43 	const char		*name;
44 	phys_addr_t		addr;
45 	dma_addr_t		dma_addr;
46 	unsigned long		offs;
47 	resource_size_t		size;
48 	int			memtype;
49 	void __iomem		*internal_addr;
50 	struct device		*dma_device;
51 	struct uio_map		*map;
52 };
53 
54 #define MAX_UIO_MAPS	5
55 
56 struct uio_portio;
57 
58 /**
59  * struct uio_port - description of a UIO port region
60  * @name:		name of the port region for identification
61  * @start:		start of port region
62  * @size:		size of port region
63  * @porttype:		type of port (see UIO_PORT_* below)
64  * @portio:		for use by the UIO core only.
65  */
66 struct uio_port {
67 	const char		*name;
68 	unsigned long		start;
69 	unsigned long		size;
70 	int			porttype;
71 	struct uio_portio	*portio;
72 };
73 
74 #define MAX_UIO_PORT_REGIONS	5
75 
76 struct uio_device {
77 	struct module           *owner;
78 	struct device		dev;
79 	int                     minor;
80 	atomic_t                event;
81 	struct fasync_struct    *async_queue;
82 	wait_queue_head_t       wait;
83 	struct uio_info         *info;
84 	struct mutex		info_lock;
85 	struct kobject          *map_dir;
86 	struct kobject          *portio_dir;
87 };
88 
89 /**
90  * struct uio_info - UIO device capabilities
91  * @uio_dev:		the UIO device this info belongs to
92  * @name:		device name
93  * @version:		device driver version
94  * @mem:		list of mappable memory regions, size==0 for end of list
95  * @port:		list of port regions, size==0 for end of list
96  * @irq:		interrupt number or UIO_IRQ_CUSTOM
97  * @irq_flags:		flags for request_irq()
98  * @priv:		optional private data
99  * @handler:		the device's irq handler
100  * @mmap:		mmap operation for this uio device
101  * @open:		open operation for this uio device
102  * @release:		release operation for this uio device
103  * @irqcontrol:		disable/enable irqs when 0/1 is written to /dev/uioX
104  */
105 struct uio_info {
106 	struct uio_device	*uio_dev;
107 	const char		*name;
108 	const char		*version;
109 	struct uio_mem		mem[MAX_UIO_MAPS];
110 	struct uio_port		port[MAX_UIO_PORT_REGIONS];
111 	long			irq;
112 	unsigned long		irq_flags;
113 	void			*priv;
114 	irqreturn_t (*handler)(int irq, struct uio_info *dev_info);
115 	int (*mmap)(struct uio_info *info, struct vm_area_struct *vma);
116 	int (*open)(struct uio_info *info, struct inode *inode);
117 	int (*release)(struct uio_info *info, struct inode *inode);
118 	int (*irqcontrol)(struct uio_info *info, s32 irq_on);
119 };
120 
121 extern int __must_check
122 	__uio_register_device(struct module *owner,
123 			      struct device *parent,
124 			      struct uio_info *info);
125 
126 /* use a define to avoid include chaining to get THIS_MODULE */
127 
128 /**
129  * uio_register_device - register a new userspace IO device
130  * @parent:	parent device
131  * @info:	UIO device capabilities
132  *
133  * returns zero on success or a negative error code.
134  */
135 #define uio_register_device(parent, info) \
136 	__uio_register_device(THIS_MODULE, parent, info)
137 
138 extern void uio_unregister_device(struct uio_info *info);
139 extern void uio_event_notify(struct uio_info *info);
140 
141 extern int __must_check
142 	__devm_uio_register_device(struct module *owner,
143 				   struct device *parent,
144 				   struct uio_info *info);
145 
146 /* use a define to avoid include chaining to get THIS_MODULE */
147 
148 /**
149  * devm_uio_register_device - Resource managed uio_register_device()
150  * @parent:	parent device
151  * @info:	UIO device capabilities
152  *
153  * returns zero on success or a negative error code.
154  */
155 #define devm_uio_register_device(parent, info) \
156 	__devm_uio_register_device(THIS_MODULE, parent, info)
157 
158 /* defines for uio_info->irq */
159 #define UIO_IRQ_CUSTOM	-1
160 #define UIO_IRQ_NONE	0
161 
162 /* defines for uio_mem->memtype */
163 #define UIO_MEM_NONE	0
164 #define UIO_MEM_PHYS	1
165 #define UIO_MEM_LOGICAL	2
166 #define UIO_MEM_VIRTUAL 3
167 #define UIO_MEM_IOVA	4
168 /*
169  * UIO_MEM_DMA_COHERENT exists for legacy drivers that had been getting by with
170  * improperly mapping DMA coherent allocations through the other modes.
171  * Do not use in new drivers.
172  */
173 #define UIO_MEM_DMA_COHERENT	5
174 
175 /* defines for uio_port->porttype */
176 #define UIO_PORT_NONE	0
177 #define UIO_PORT_X86	1
178 #define UIO_PORT_GPIO	2
179 #define UIO_PORT_OTHER	3
180 
181 #endif /* _LINUX_UIO_DRIVER_H_ */
182