1 | /* |
2 | * vga_switcheroo.h - Support for laptop with dual GPU using one set of outputs |
3 | * |
4 | * Copyright (c) 2010 Red Hat Inc. |
5 | * Author : Dave Airlie <airlied@redhat.com> |
6 | * |
7 | * Copyright (c) 2015 Lukas Wunner <lukas@wunner.de> |
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_SWITCHEROO_H_ |
32 | #define _LINUX_VGA_SWITCHEROO_H_ |
33 | |
34 | #include <linux/fb.h> |
35 | |
36 | struct pci_dev; |
37 | |
38 | /** |
39 | * enum vga_switcheroo_handler_flags_t - handler flags bitmask |
40 | * @VGA_SWITCHEROO_CAN_SWITCH_DDC: whether the handler is able to switch the |
41 | * DDC lines separately. This signals to clients that they should call |
42 | * drm_get_edid_switcheroo() to probe the EDID |
43 | * @VGA_SWITCHEROO_NEEDS_EDP_CONFIG: whether the handler is unable to switch |
44 | * the AUX channel separately. This signals to clients that the active |
45 | * GPU needs to train the link and communicate the link parameters to the |
46 | * inactive GPU (mediated by vga_switcheroo). The inactive GPU may then |
47 | * skip the AUX handshake and set up its output with these pre-calibrated |
48 | * values (DisplayPort specification v1.1a, section 2.5.3.3) |
49 | * |
50 | * Handler flags bitmask. Used by handlers to declare their capabilities upon |
51 | * registering with vga_switcheroo. |
52 | */ |
53 | enum vga_switcheroo_handler_flags_t { |
54 | VGA_SWITCHEROO_CAN_SWITCH_DDC = (1 << 0), |
55 | VGA_SWITCHEROO_NEEDS_EDP_CONFIG = (1 << 1), |
56 | }; |
57 | |
58 | /** |
59 | * enum vga_switcheroo_state - client power state |
60 | * @VGA_SWITCHEROO_OFF: off |
61 | * @VGA_SWITCHEROO_ON: on |
62 | * @VGA_SWITCHEROO_NOT_FOUND: client has not registered with vga_switcheroo. |
63 | * Only used in vga_switcheroo_get_client_state() which in turn is only |
64 | * called from hda_intel.c |
65 | * |
66 | * Client power state. |
67 | */ |
68 | enum vga_switcheroo_state { |
69 | VGA_SWITCHEROO_OFF, |
70 | VGA_SWITCHEROO_ON, |
71 | /* below are referred only from vga_switcheroo_get_client_state() */ |
72 | VGA_SWITCHEROO_NOT_FOUND, |
73 | }; |
74 | |
75 | /** |
76 | * enum vga_switcheroo_client_id - client identifier |
77 | * @VGA_SWITCHEROO_UNKNOWN_ID: initial identifier assigned to vga clients. |
78 | * Determining the id requires the handler, so GPUs are given their |
79 | * true id in a delayed fashion in vga_switcheroo_enable() |
80 | * @VGA_SWITCHEROO_IGD: integrated graphics device |
81 | * @VGA_SWITCHEROO_DIS: discrete graphics device |
82 | * @VGA_SWITCHEROO_MAX_CLIENTS: currently no more than two GPUs are supported |
83 | * |
84 | * Client identifier. Audio clients use the same identifier & 0x100. |
85 | */ |
86 | enum vga_switcheroo_client_id { |
87 | VGA_SWITCHEROO_UNKNOWN_ID = 0x1000, |
88 | VGA_SWITCHEROO_IGD = 0, |
89 | VGA_SWITCHEROO_DIS, |
90 | VGA_SWITCHEROO_MAX_CLIENTS, |
91 | }; |
92 | |
93 | /** |
94 | * struct vga_switcheroo_handler - handler callbacks |
95 | * @init: initialize handler. |
96 | * Optional. This gets called when vga_switcheroo is enabled, i.e. when |
97 | * two vga clients have registered. It allows the handler to perform |
98 | * some delayed initialization that depends on the existence of the |
99 | * vga clients. Currently only the radeon and amdgpu drivers use this. |
100 | * The return value is ignored |
101 | * @switchto: switch outputs to given client. |
102 | * Mandatory. For muxless machines this should be a no-op. Returning 0 |
103 | * denotes success, anything else failure (in which case the switch is |
104 | * aborted) |
105 | * @switch_ddc: switch DDC lines to given client. |
106 | * Optional. Should return the previous DDC owner on success or a |
107 | * negative int on failure |
108 | * @power_state: cut or reinstate power of given client. |
109 | * Optional. The return value is ignored |
110 | * @get_client_id: determine if given pci device is integrated or discrete GPU. |
111 | * Mandatory |
112 | * |
113 | * Handler callbacks. The multiplexer itself. The @switchto and @get_client_id |
114 | * methods are mandatory, all others may be set to NULL. |
115 | */ |
116 | struct vga_switcheroo_handler { |
117 | int (*init)(void); |
118 | int (*switchto)(enum vga_switcheroo_client_id id); |
119 | int (*switch_ddc)(enum vga_switcheroo_client_id id); |
120 | int (*power_state)(enum vga_switcheroo_client_id id, |
121 | enum vga_switcheroo_state state); |
122 | enum vga_switcheroo_client_id (*get_client_id)(struct pci_dev *pdev); |
123 | }; |
124 | |
125 | /** |
126 | * struct vga_switcheroo_client_ops - client callbacks |
127 | * @set_gpu_state: do the equivalent of suspend/resume for the card. |
128 | * Mandatory. This should not cut power to the discrete GPU, |
129 | * which is the job of the handler |
130 | * @reprobe: poll outputs. |
131 | * Optional. This gets called after waking the GPU and switching |
132 | * the outputs to it |
133 | * @can_switch: check if the device is in a position to switch now. |
134 | * Mandatory. The client should return false if a user space process |
135 | * has one of its device files open |
136 | * @gpu_bound: notify the client id to audio client when the GPU is bound. |
137 | * |
138 | * Client callbacks. A client can be either a GPU or an audio device on a GPU. |
139 | * The @set_gpu_state and @can_switch methods are mandatory, @reprobe may be |
140 | * set to NULL. For audio clients, the @reprobe member is bogus. |
141 | * OTOH, @gpu_bound is only for audio clients, and not used for GPU clients. |
142 | */ |
143 | struct vga_switcheroo_client_ops { |
144 | void (*set_gpu_state)(struct pci_dev *dev, enum vga_switcheroo_state); |
145 | void (*reprobe)(struct pci_dev *dev); |
146 | bool (*can_switch)(struct pci_dev *dev); |
147 | void (*gpu_bound)(struct pci_dev *dev, enum vga_switcheroo_client_id); |
148 | }; |
149 | |
150 | #if defined(CONFIG_VGA_SWITCHEROO) |
151 | void vga_switcheroo_unregister_client(struct pci_dev *dev); |
152 | int vga_switcheroo_register_client(struct pci_dev *dev, |
153 | const struct vga_switcheroo_client_ops *ops, |
154 | bool driver_power_control); |
155 | int vga_switcheroo_register_audio_client(struct pci_dev *pdev, |
156 | const struct vga_switcheroo_client_ops *ops, |
157 | struct pci_dev *vga_dev); |
158 | |
159 | void vga_switcheroo_client_fb_set(struct pci_dev *dev, |
160 | struct fb_info *info); |
161 | |
162 | int vga_switcheroo_register_handler(const struct vga_switcheroo_handler *handler, |
163 | enum vga_switcheroo_handler_flags_t handler_flags); |
164 | void vga_switcheroo_unregister_handler(void); |
165 | enum vga_switcheroo_handler_flags_t vga_switcheroo_handler_flags(void); |
166 | int vga_switcheroo_lock_ddc(struct pci_dev *pdev); |
167 | int vga_switcheroo_unlock_ddc(struct pci_dev *pdev); |
168 | |
169 | int vga_switcheroo_process_delayed_switch(void); |
170 | |
171 | bool vga_switcheroo_client_probe_defer(struct pci_dev *pdev); |
172 | enum vga_switcheroo_state vga_switcheroo_get_client_state(struct pci_dev *dev); |
173 | |
174 | int vga_switcheroo_init_domain_pm_ops(struct device *dev, struct dev_pm_domain *domain); |
175 | void vga_switcheroo_fini_domain_pm_ops(struct device *dev); |
176 | #else |
177 | |
178 | static inline void vga_switcheroo_unregister_client(struct pci_dev *dev) {} |
179 | static inline int vga_switcheroo_register_client(struct pci_dev *dev, |
180 | const struct vga_switcheroo_client_ops *ops, bool driver_power_control) { return 0; } |
181 | static inline void vga_switcheroo_client_fb_set(struct pci_dev *dev, struct fb_info *info) {} |
182 | static inline int vga_switcheroo_register_handler(const struct vga_switcheroo_handler *handler, |
183 | enum vga_switcheroo_handler_flags_t handler_flags) { return 0; } |
184 | static inline int vga_switcheroo_register_audio_client(struct pci_dev *pdev, |
185 | const struct vga_switcheroo_client_ops *ops, |
186 | struct pci_dev *vga_dev) { return 0; } |
187 | static inline void vga_switcheroo_unregister_handler(void) {} |
188 | static inline enum vga_switcheroo_handler_flags_t vga_switcheroo_handler_flags(void) { return 0; } |
189 | static inline int vga_switcheroo_lock_ddc(struct pci_dev *pdev) { return -ENODEV; } |
190 | static inline int vga_switcheroo_unlock_ddc(struct pci_dev *pdev) { return -ENODEV; } |
191 | static inline int vga_switcheroo_process_delayed_switch(void) { return 0; } |
192 | static inline bool vga_switcheroo_client_probe_defer(struct pci_dev *pdev) { return false; } |
193 | static inline enum vga_switcheroo_state vga_switcheroo_get_client_state(struct pci_dev *dev) { return VGA_SWITCHEROO_ON; } |
194 | |
195 | static inline int vga_switcheroo_init_domain_pm_ops(struct device *dev, struct dev_pm_domain *domain) { return -EINVAL; } |
196 | static inline void vga_switcheroo_fini_domain_pm_ops(struct device *dev) {} |
197 | |
198 | #endif |
199 | #endif /* _LINUX_VGA_SWITCHEROO_H_ */ |
200 | |