/*
* vga_switcheroo.h - Support for laptop with dual GPU using one set of outputs
*
* Copyright (c) 2010 Red Hat Inc.
* Author : Dave Airlie <[email protected]>
*
* Copyright (c) 2015 Lukas Wunner <[email protected]>
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS
* IN THE SOFTWARE.
*
*/
#ifndef _LINUX_VGA_SWITCHEROO_H_
#define _LINUX_VGA_SWITCHEROO_H_
#include <linux/fb.h>
struct pci_dev;
/**
* enum vga_switcheroo_handler_flags_t - handler flags bitmask
* @VGA_SWITCHEROO_CAN_SWITCH_DDC: whether the handler is able to switch the
* DDC lines separately. This signals to clients that they should call
* drm_get_edid_switcheroo() to probe the EDID
* @VGA_SWITCHEROO_NEEDS_EDP_CONFIG: whether the handler is unable to switch
* the AUX channel separately. This signals to clients that the active
* GPU needs to train the link and communicate the link parameters to the
* inactive GPU (mediated by vga_switcheroo). The inactive GPU may then
* skip the AUX handshake and set up its output with these pre-calibrated
* values (DisplayPort specification v1.1a, section 2.5.3.3)
*
* Handler flags bitmask. Used by handlers to declare their capabilities upon
* registering with vga_switcheroo.
*/
enum vga_switcheroo_handler_flags_t {
VGA_SWITCHEROO_CAN_SWITCH_DDC = (1 << 0),
VGA_SWITCHEROO_NEEDS_EDP_CONFIG = (1 << 1),
};
/**
* enum vga_switcheroo_state - client power state
* @VGA_SWITCHEROO_OFF: off
* @VGA_SWITCHEROO_ON: on
* @VGA_SWITCHEROO_NOT_FOUND: client has not registered with vga_switcheroo.
* Only used in vga_switcheroo_get_client_state() which in turn is only
* called from hda_intel.c
*
* Client power state.
*/
enum vga_switcheroo_state {
VGA_SWITCHEROO_OFF,
VGA_SWITCHEROO_ON,
/* below are referred only from vga_switcheroo_get_client_state() */
VGA_SWITCHEROO_NOT_FOUND,
};
/**
* enum vga_switcheroo_client_id - client identifier
* @VGA_SWITCHEROO_UNKNOWN_ID: initial identifier assigned to vga clients.
* Determining the id requires the handler, so GPUs are given their
* true id in a delayed fashion in vga_switcheroo_enable()
* @VGA_SWITCHEROO_IGD: integrated graphics device
* @VGA_SWITCHEROO_DIS: discrete graphics device
* @VGA_SWITCHEROO_MAX_CLIENTS: currently no more than two GPUs are supported
*
* Client identifier. Audio clients use the same identifier & 0x100.
*/
enum vga_switcheroo_client_id {
VGA_SWITCHEROO_UNKNOWN_ID = 0x1000,
VGA_SWITCHEROO_IGD = 0,
VGA_SWITCHEROO_DIS,
VGA_SWITCHEROO_MAX_CLIENTS,
};
/**
* struct vga_switcheroo_handler - handler callbacks
* @init: initialize handler.
* Optional. This gets called when vga_switcheroo is enabled, i.e. when
* two vga clients have registered. It allows the handler to perform
* some delayed initialization that depends on the existence of the
* vga clients. Currently only the radeon and amdgpu drivers use this.
* The return value is ignored
* @switchto: switch outputs to given client.
* Mandatory. For muxless machines this should be a no-op. Returning 0
* denotes success, anything else failure (in which case the switch is
* aborted)
* @switch_ddc: switch DDC lines to given client.
* Optional. Should return the previous DDC owner on success or a
* negative int on failure
* @power_state: cut or reinstate power of given client.
* Optional. The return value is ignored
* @get_client_id: determine if given pci device is integrated or discrete GPU.
* Mandatory
*
* Handler callbacks. The multiplexer itself. The @switchto and @get_client_id
* methods are mandatory, all others may be set to NULL.
*/
struct vga_switcheroo_handler {
int (*init)(void);
int (*switchto)(enum vga_switcheroo_client_id id);
int (*switch_ddc)(enum vga_switcheroo_client_id id);
int (*power_state)(enum vga_switcheroo_client_id id,
enum vga_switcheroo_state state);
enum vga_switcheroo_client_id (*get_client_id)(struct pci_dev *pdev);
};
/**
* struct vga_switcheroo_client_ops - client callbacks
* @set_gpu_state: do the equivalent of suspend/resume for the card.
* Mandatory. This should not cut power to the discrete GPU,
* which is the job of the handler
* @reprobe: poll outputs.
* Optional. This gets called after waking the GPU and switching
* the outputs to it
* @can_switch: check if the device is in a position to switch now.
* Mandatory. The client should return false if a user space process
* has one of its device files open
* @gpu_bound: notify the client id to audio client when the GPU is bound.
*
* Client callbacks. A client can be either a GPU or an audio device on a GPU.
* The @set_gpu_state and @can_switch methods are mandatory, @reprobe may be
* set to NULL. For audio clients, the @reprobe member is bogus.
* OTOH, @gpu_bound is only for audio clients, and not used for GPU clients.
*/
struct vga_switcheroo_client_ops {
void (*set_gpu_state)(struct pci_dev *dev, enum vga_switcheroo_state);
void (*reprobe)(struct pci_dev *dev);
bool (*can_switch)(struct pci_dev *dev);
void (*gpu_bound)(struct pci_dev *dev, enum vga_switcheroo_client_id);
};
#if defined(CONFIG_VGA_SWITCHEROO)
void vga_switcheroo_unregister_client(struct pci_dev *dev);
int vga_switcheroo_register_client(struct pci_dev *dev,
const struct vga_switcheroo_client_ops *ops,
bool driver_power_control);
int vga_switcheroo_register_audio_client(struct pci_dev *pdev,
const struct vga_switcheroo_client_ops *ops,
struct pci_dev *vga_dev);
void vga_switcheroo_client_fb_set(struct pci_dev *dev,
struct fb_info *info);
int vga_switcheroo_register_handler(const struct vga_switcheroo_handler *handler,
enum vga_switcheroo_handler_flags_t handler_flags);
void vga_switcheroo_unregister_handler(void);
enum vga_switcheroo_handler_flags_t vga_switcheroo_handler_flags(void);
int vga_switcheroo_lock_ddc(struct pci_dev *pdev);
int vga_switcheroo_unlock_ddc(struct pci_dev *pdev);
int vga_switcheroo_process_delayed_switch(void);
bool vga_switcheroo_client_probe_defer(struct pci_dev *pdev);
enum vga_switcheroo_state vga_switcheroo_get_client_state(struct pci_dev *dev);
int vga_switcheroo_init_domain_pm_ops(struct device *dev, struct dev_pm_domain *domain);
void vga_switcheroo_fini_domain_pm_ops(struct device *dev);
#else
static inline void vga_switcheroo_unregister_client(struct pci_dev *dev) {}
static inline int vga_switcheroo_register_client(struct pci_dev *dev,
const struct vga_switcheroo_client_ops *ops, bool driver_power_control) { return 0; }
static inline void vga_switcheroo_client_fb_set(struct pci_dev *dev, struct fb_info *info) {}
static inline int vga_switcheroo_register_handler(const struct vga_switcheroo_handler *handler,
enum vga_switcheroo_handler_flags_t handler_flags) { return 0; }
static inline int vga_switcheroo_register_audio_client(struct pci_dev *pdev,
const struct vga_switcheroo_client_ops *ops,
struct pci_dev *vga_dev) { return 0; }
static inline void vga_switcheroo_unregister_handler(void) {}
static inline enum vga_switcheroo_handler_flags_t vga_switcheroo_handler_flags(void) { return 0; }
static inline int vga_switcheroo_lock_ddc(struct pci_dev *pdev) { return -ENODEV; }
static inline int vga_switcheroo_unlock_ddc(struct pci_dev *pdev) { return -ENODEV; }
static inline int vga_switcheroo_process_delayed_switch(void) { return 0; }
static inline bool vga_switcheroo_client_probe_defer(struct pci_dev *pdev) { return false; }
static inline enum vga_switcheroo_state vga_switcheroo_get_client_state(struct pci_dev *dev) { return VGA_SWITCHEROO_ON; }
static inline int vga_switcheroo_init_domain_pm_ops(struct device *dev, struct dev_pm_domain *domain) { return -EINVAL; }
static inline void vga_switcheroo_fini_domain_pm_ops(struct device *dev) {}
#endif
#endif /* _LINUX_VGA_SWITCHEROO_H_ */
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