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 36struct 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 */ 53enum 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 */ 68enum 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 */ 86enum 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 */ 116struct 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 */ 143struct 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) 151void vga_switcheroo_unregister_client(struct pci_dev *dev); 152int vga_switcheroo_register_client(struct pci_dev *dev, 153 const struct vga_switcheroo_client_ops *ops, 154 bool driver_power_control); 155int vga_switcheroo_register_audio_client(struct pci_dev *pdev, 156 const struct vga_switcheroo_client_ops *ops, 157 struct pci_dev *vga_dev); 158 159void vga_switcheroo_client_fb_set(struct pci_dev *dev, 160 struct fb_info *info); 161 162int vga_switcheroo_register_handler(const struct vga_switcheroo_handler *handler, 163 enum vga_switcheroo_handler_flags_t handler_flags); 164void vga_switcheroo_unregister_handler(void); 165enum vga_switcheroo_handler_flags_t vga_switcheroo_handler_flags(void); 166int vga_switcheroo_lock_ddc(struct pci_dev *pdev); 167int vga_switcheroo_unlock_ddc(struct pci_dev *pdev); 168 169int vga_switcheroo_process_delayed_switch(void); 170 171bool vga_switcheroo_client_probe_defer(struct pci_dev *pdev); 172enum vga_switcheroo_state vga_switcheroo_get_client_state(struct pci_dev *dev); 173 174int vga_switcheroo_init_domain_pm_ops(struct device *dev, struct dev_pm_domain *domain); 175void vga_switcheroo_fini_domain_pm_ops(struct device *dev); 176#else 177 178static inline void vga_switcheroo_unregister_client(struct pci_dev *dev) {} 179static inline int vga_switcheroo_register_client(struct pci_dev *dev, 180 const struct vga_switcheroo_client_ops *ops, bool driver_power_control) { return 0; } 181static inline void vga_switcheroo_client_fb_set(struct pci_dev *dev, struct fb_info *info) {} 182static inline int vga_switcheroo_register_handler(const struct vga_switcheroo_handler *handler, 183 enum vga_switcheroo_handler_flags_t handler_flags) { return 0; } 184static 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; } 187static inline void vga_switcheroo_unregister_handler(void) {} 188static inline enum vga_switcheroo_handler_flags_t vga_switcheroo_handler_flags(void) { return 0; } 189static inline int vga_switcheroo_lock_ddc(struct pci_dev *pdev) { return -ENODEV; } 190static inline int vga_switcheroo_unlock_ddc(struct pci_dev *pdev) { return -ENODEV; } 191static inline int vga_switcheroo_process_delayed_switch(void) { return 0; } 192static inline bool vga_switcheroo_client_probe_defer(struct pci_dev *pdev) { return false; } 193static inline enum vga_switcheroo_state vga_switcheroo_get_client_state(struct pci_dev *dev) { return VGA_SWITCHEROO_ON; } 194 195static inline int vga_switcheroo_init_domain_pm_ops(struct device *dev, struct dev_pm_domain *domain) { return -EINVAL; } 196static inline void vga_switcheroo_fini_domain_pm_ops(struct device *dev) {} 197 198#endif 199#endif /* _LINUX_VGA_SWITCHEROO_H_ */ 200