1 /*
2  * The VGA aribiter manages VGA space routing and VGA resource decode to
3  * allow multiple VGA devices to be used in a system in a safe way.
4  *
5  * (C) Copyright 2005 Benjamin Herrenschmidt <benh@kernel.crashing.org>
6  * (C) Copyright 2007 Paulo R. Zanoni <przanoni@gmail.com>
7  * (C) Copyright 2007, 2009 Tiago Vignatti <vignatti@freedesktop.org>
8  *
9  * Permission is hereby granted, free of charge, to any person obtaining a
10  * copy of this software and associated documentation files (the "Software"),
11  * to deal in the Software without restriction, including without limitation
12  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
13  * and/or sell copies of the Software, and to permit persons to whom the
14  * Software is furnished to do so, subject to the following conditions:
15  *
16  * The above copyright notice and this permission notice (including the next
17  * paragraph) shall be included in all copies or substantial portions of the
18  * Software.
19  *
20  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
23  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
24  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
25  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
26  * DEALINGS
27  * IN THE SOFTWARE.
28  *
29  */
30 
31 #ifndef LINUX_VGA_H
32 #define LINUX_VGA_H
33 
34 #include <video/vga.h>
35 
36 struct pci_dev;
37 
38 /* Legacy VGA regions */
39 #define VGA_RSRC_NONE	       0x00
40 #define VGA_RSRC_LEGACY_IO     0x01
41 #define VGA_RSRC_LEGACY_MEM    0x02
42 #define VGA_RSRC_LEGACY_MASK   (VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM)
43 /* Non-legacy access */
44 #define VGA_RSRC_NORMAL_IO     0x04
45 #define VGA_RSRC_NORMAL_MEM    0x08
46 
47 #ifdef CONFIG_VGA_ARB
48 void vga_set_legacy_decoding(struct pci_dev *pdev, unsigned int decodes);
49 int vga_get(struct pci_dev *pdev, unsigned int rsrc, int interruptible);
50 void vga_put(struct pci_dev *pdev, unsigned int rsrc);
51 struct pci_dev *vga_default_device(void);
52 void vga_set_default_device(struct pci_dev *pdev);
53 int vga_remove_vgacon(struct pci_dev *pdev);
54 int vga_client_register(struct pci_dev *pdev,
55 		unsigned int (*set_decode)(struct pci_dev *pdev, bool state));
56 #else /* CONFIG_VGA_ARB */
vga_set_legacy_decoding(struct pci_dev * pdev,unsigned int decodes)57 static inline void vga_set_legacy_decoding(struct pci_dev *pdev,
58 		unsigned int decodes)
59 {
60 };
vga_get(struct pci_dev * pdev,unsigned int rsrc,int interruptible)61 static inline int vga_get(struct pci_dev *pdev, unsigned int rsrc,
62 		int interruptible)
63 {
64 	return 0;
65 }
vga_put(struct pci_dev * pdev,unsigned int rsrc)66 static inline void vga_put(struct pci_dev *pdev, unsigned int rsrc)
67 {
68 }
vga_default_device(void)69 static inline struct pci_dev *vga_default_device(void)
70 {
71 	return NULL;
72 }
vga_set_default_device(struct pci_dev * pdev)73 static inline void vga_set_default_device(struct pci_dev *pdev)
74 {
75 }
vga_remove_vgacon(struct pci_dev * pdev)76 static inline int vga_remove_vgacon(struct pci_dev *pdev)
77 {
78 	return 0;
79 }
vga_client_register(struct pci_dev * pdev,unsigned int (* set_decode)(struct pci_dev * pdev,bool state))80 static inline int vga_client_register(struct pci_dev *pdev,
81 		unsigned int (*set_decode)(struct pci_dev *pdev, bool state))
82 {
83 	return 0;
84 }
85 #endif /* CONFIG_VGA_ARB */
86 
87 /**
88  * vga_get_interruptible
89  * @pdev: pci device of the VGA card or NULL for the system default
90  * @rsrc: bit mask of resources to acquire and lock
91  *
92  * Shortcut to vga_get with interruptible set to true.
93  *
94  * On success, release the VGA resource again with vga_put().
95  */
vga_get_interruptible(struct pci_dev * pdev,unsigned int rsrc)96 static inline int vga_get_interruptible(struct pci_dev *pdev,
97 					unsigned int rsrc)
98 {
99        return vga_get(pdev, rsrc, 1);
100 }
101 
102 /**
103  * vga_get_uninterruptible - shortcut to vga_get()
104  * @pdev: pci device of the VGA card or NULL for the system default
105  * @rsrc: bit mask of resources to acquire and lock
106  *
107  * Shortcut to vga_get with interruptible set to false.
108  *
109  * On success, release the VGA resource again with vga_put().
110  */
vga_get_uninterruptible(struct pci_dev * pdev,unsigned int rsrc)111 static inline int vga_get_uninterruptible(struct pci_dev *pdev,
112 					  unsigned int rsrc)
113 {
114        return vga_get(pdev, rsrc, 0);
115 }
116 
vga_client_unregister(struct pci_dev * pdev)117 static inline void vga_client_unregister(struct pci_dev *pdev)
118 {
119 	vga_client_register(pdev, NULL);
120 }
121 
122 #endif /* LINUX_VGA_H */
123