123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678679680681682683684685686687688689690691692693694695696697698699700701702703704705706707708709710711712713714715716717718719720721722723724725726727728729730731732733734735736737738739740741742743744745746747748749750751752753754755756757758759760761762763764765766767768769770771772773774775776777778779780781782783784785786787788789790791792793794795796797798799800801802803804805806807808809810811812813814815816817818819820821822823824825826827828829830831832833834835836837838839840841842843844845846847848849850851852853854855856857858859860861862863864865866867868869870871872873874875876877878879880881882883884885886887888889890891892893894895896897898899900901902903904905906907908909910911912913914915916917918919920921922923924925926927928929930931932933934935936937938939940941942943944945946947948949950951952953954955956957958959960961962963964965966967968969970971972973974975976977978979980981982983984985986987988989990991992993994995996997998 |
- /*
- * vga_switcheroo.c - Support for laptop with dual GPU using one set of outputs
- *
- * Copyright (c) 2010 Red Hat Inc.
- * Author : Dave Airlie <airlied@redhat.com>
- *
- * Copyright (c) 2015 Lukas Wunner <lukas@wunner.de>
- *
- * 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.
- *
- */
- #define pr_fmt(fmt) "vga_switcheroo: " fmt
- #include <linux/console.h>
- #include <linux/debugfs.h>
- #include <linux/fb.h>
- #include <linux/fs.h>
- #include <linux/module.h>
- #include <linux/pci.h>
- #include <linux/pm_runtime.h>
- #include <linux/seq_file.h>
- #include <linux/uaccess.h>
- #include <linux/vgaarb.h>
- #include <linux/vga_switcheroo.h>
- /**
- * DOC: Overview
- *
- * vga_switcheroo is the Linux subsystem for laptop hybrid graphics.
- * These come in two flavors:
- *
- * * muxed: Dual GPUs with a multiplexer chip to switch outputs between GPUs.
- * * muxless: Dual GPUs but only one of them is connected to outputs.
- * The other one is merely used to offload rendering, its results
- * are copied over PCIe into the framebuffer. On Linux this is
- * supported with DRI PRIME.
- *
- * Hybrid graphics started to appear in the late Naughties and were initially
- * all muxed. Newer laptops moved to a muxless architecture for cost reasons.
- * A notable exception is the MacBook Pro which continues to use a mux.
- * Muxes come with varying capabilities: Some switch only the panel, others
- * can also switch external displays. Some switch all display pins at once
- * while others can switch just the DDC lines. (To allow EDID probing
- * for the inactive GPU.) Also, muxes are often used to cut power to the
- * discrete GPU while it is not used.
- *
- * DRM drivers register GPUs with vga_switcheroo, these are heretoforth called
- * clients. The mux is called the handler. Muxless machines also register a
- * handler to control the power state of the discrete GPU, its ->switchto
- * callback is a no-op for obvious reasons. The discrete GPU is often equipped
- * with an HDA controller for the HDMI/DP audio signal, this will also
- * register as a client so that vga_switcheroo can take care of the correct
- * suspend/resume order when changing the discrete GPU's power state. In total
- * there can thus be up to three clients: Two vga clients (GPUs) and one audio
- * client (on the discrete GPU). The code is mostly prepared to support
- * machines with more than two GPUs should they become available.
- * The GPU to which the outputs are currently switched is called the
- * active client in vga_switcheroo parlance. The GPU not in use is the
- * inactive client.
- */
- /**
- * struct vga_switcheroo_client - registered client
- * @pdev: client pci device
- * @fb_info: framebuffer to which console is remapped on switching
- * @pwr_state: current power state
- * @ops: client callbacks
- * @id: client identifier. Determining the id requires the handler,
- * so gpus are initially assigned VGA_SWITCHEROO_UNKNOWN_ID
- * and later given their true id in vga_switcheroo_enable()
- * @active: whether the outputs are currently switched to this client
- * @driver_power_control: whether power state is controlled by the driver's
- * runtime pm. If true, writing ON and OFF to the vga_switcheroo debugfs
- * interface is a no-op so as not to interfere with runtime pm
- * @list: client list
- *
- * Registered client. A client can be either a GPU or an audio device on a GPU.
- * For audio clients, the @fb_info, @active and @driver_power_control members
- * are bogus.
- */
- struct vga_switcheroo_client {
- struct pci_dev *pdev;
- struct fb_info *fb_info;
- enum vga_switcheroo_state pwr_state;
- const struct vga_switcheroo_client_ops *ops;
- enum vga_switcheroo_client_id id;
- bool active;
- bool driver_power_control;
- struct list_head list;
- };
- /*
- * protects access to struct vgasr_priv
- */
- static DEFINE_MUTEX(vgasr_mutex);
- /**
- * struct vgasr_priv - vga_switcheroo private data
- * @active: whether vga_switcheroo is enabled.
- * Prerequisite is the registration of two GPUs and a handler
- * @delayed_switch_active: whether a delayed switch is pending
- * @delayed_client_id: client to which a delayed switch is pending
- * @debugfs_root: directory for vga_switcheroo debugfs interface
- * @switch_file: file for vga_switcheroo debugfs interface
- * @registered_clients: number of registered GPUs
- * (counting only vga clients, not audio clients)
- * @clients: list of registered clients
- * @handler: registered handler
- *
- * vga_switcheroo private data. Currently only one vga_switcheroo instance
- * per system is supported.
- */
- struct vgasr_priv {
- bool active;
- bool delayed_switch_active;
- enum vga_switcheroo_client_id delayed_client_id;
- struct dentry *debugfs_root;
- struct dentry *switch_file;
- int registered_clients;
- struct list_head clients;
- const struct vga_switcheroo_handler *handler;
- };
- #define ID_BIT_AUDIO 0x100
- #define client_is_audio(c) ((c)->id & ID_BIT_AUDIO)
- #define client_is_vga(c) ((c)->id == VGA_SWITCHEROO_UNKNOWN_ID || \
- !client_is_audio(c))
- #define client_id(c) ((c)->id & ~ID_BIT_AUDIO)
- static int vga_switcheroo_debugfs_init(struct vgasr_priv *priv);
- static void vga_switcheroo_debugfs_fini(struct vgasr_priv *priv);
- /* only one switcheroo per system */
- static struct vgasr_priv vgasr_priv = {
- .clients = LIST_HEAD_INIT(vgasr_priv.clients),
- };
- static bool vga_switcheroo_ready(void)
- {
- /* we're ready if we get two clients + handler */
- return !vgasr_priv.active &&
- vgasr_priv.registered_clients == 2 && vgasr_priv.handler;
- }
- static void vga_switcheroo_enable(void)
- {
- int ret;
- struct vga_switcheroo_client *client;
- /* call the handler to init */
- if (vgasr_priv.handler->init)
- vgasr_priv.handler->init();
- list_for_each_entry(client, &vgasr_priv.clients, list) {
- if (client->id != VGA_SWITCHEROO_UNKNOWN_ID)
- continue;
- ret = vgasr_priv.handler->get_client_id(client->pdev);
- if (ret < 0)
- return;
- client->id = ret;
- }
- vga_switcheroo_debugfs_init(&vgasr_priv);
- vgasr_priv.active = true;
- }
- /**
- * vga_switcheroo_register_handler() - register handler
- * @handler: handler callbacks
- *
- * Register handler. Enable vga_switcheroo if two vga clients have already
- * registered.
- *
- * Return: 0 on success, -EINVAL if a handler was already registered.
- */
- int vga_switcheroo_register_handler(const struct vga_switcheroo_handler *handler)
- {
- mutex_lock(&vgasr_mutex);
- if (vgasr_priv.handler) {
- mutex_unlock(&vgasr_mutex);
- return -EINVAL;
- }
- vgasr_priv.handler = handler;
- if (vga_switcheroo_ready()) {
- pr_info("enabled\n");
- vga_switcheroo_enable();
- }
- mutex_unlock(&vgasr_mutex);
- return 0;
- }
- EXPORT_SYMBOL(vga_switcheroo_register_handler);
- /**
- * vga_switcheroo_unregister_handler() - unregister handler
- *
- * Unregister handler. Disable vga_switcheroo.
- */
- void vga_switcheroo_unregister_handler(void)
- {
- mutex_lock(&vgasr_mutex);
- vgasr_priv.handler = NULL;
- if (vgasr_priv.active) {
- pr_info("disabled\n");
- vga_switcheroo_debugfs_fini(&vgasr_priv);
- vgasr_priv.active = false;
- }
- mutex_unlock(&vgasr_mutex);
- }
- EXPORT_SYMBOL(vga_switcheroo_unregister_handler);
- static int register_client(struct pci_dev *pdev,
- const struct vga_switcheroo_client_ops *ops,
- enum vga_switcheroo_client_id id, bool active,
- bool driver_power_control)
- {
- struct vga_switcheroo_client *client;
- client = kzalloc(sizeof(*client), GFP_KERNEL);
- if (!client)
- return -ENOMEM;
- client->pwr_state = VGA_SWITCHEROO_ON;
- client->pdev = pdev;
- client->ops = ops;
- client->id = id;
- client->active = active;
- client->driver_power_control = driver_power_control;
- mutex_lock(&vgasr_mutex);
- list_add_tail(&client->list, &vgasr_priv.clients);
- if (client_is_vga(client))
- vgasr_priv.registered_clients++;
- if (vga_switcheroo_ready()) {
- pr_info("enabled\n");
- vga_switcheroo_enable();
- }
- mutex_unlock(&vgasr_mutex);
- return 0;
- }
- /**
- * vga_switcheroo_register_client - register vga client
- * @pdev: client pci device
- * @ops: client callbacks
- * @driver_power_control: whether power state is controlled by the driver's
- * runtime pm
- *
- * Register vga client (GPU). Enable vga_switcheroo if another GPU and a
- * handler have already registered. The power state of the client is assumed
- * to be ON.
- *
- * Return: 0 on success, -ENOMEM on memory allocation error.
- */
- int vga_switcheroo_register_client(struct pci_dev *pdev,
- const struct vga_switcheroo_client_ops *ops,
- bool driver_power_control)
- {
- return register_client(pdev, ops, VGA_SWITCHEROO_UNKNOWN_ID,
- pdev == vga_default_device(),
- driver_power_control);
- }
- EXPORT_SYMBOL(vga_switcheroo_register_client);
- /**
- * vga_switcheroo_register_audio_client - register audio client
- * @pdev: client pci device
- * @ops: client callbacks
- * @id: client identifier
- *
- * Register audio client (audio device on a GPU). The power state of the
- * client is assumed to be ON.
- *
- * Return: 0 on success, -ENOMEM on memory allocation error.
- */
- int vga_switcheroo_register_audio_client(struct pci_dev *pdev,
- const struct vga_switcheroo_client_ops *ops,
- enum vga_switcheroo_client_id id)
- {
- return register_client(pdev, ops, id | ID_BIT_AUDIO, false, false);
- }
- EXPORT_SYMBOL(vga_switcheroo_register_audio_client);
- static struct vga_switcheroo_client *
- find_client_from_pci(struct list_head *head, struct pci_dev *pdev)
- {
- struct vga_switcheroo_client *client;
- list_for_each_entry(client, head, list)
- if (client->pdev == pdev)
- return client;
- return NULL;
- }
- static struct vga_switcheroo_client *
- find_client_from_id(struct list_head *head,
- enum vga_switcheroo_client_id client_id)
- {
- struct vga_switcheroo_client *client;
- list_for_each_entry(client, head, list)
- if (client->id == client_id)
- return client;
- return NULL;
- }
- static struct vga_switcheroo_client *
- find_active_client(struct list_head *head)
- {
- struct vga_switcheroo_client *client;
- list_for_each_entry(client, head, list)
- if (client->active)
- return client;
- return NULL;
- }
- /**
- * vga_switcheroo_get_client_state() - obtain power state of a given client
- * @pdev: client pci device
- *
- * Obtain power state of a given client as seen from vga_switcheroo.
- * The function is only called from hda_intel.c.
- *
- * Return: Power state.
- */
- enum vga_switcheroo_state vga_switcheroo_get_client_state(struct pci_dev *pdev)
- {
- struct vga_switcheroo_client *client;
- enum vga_switcheroo_state ret;
- mutex_lock(&vgasr_mutex);
- client = find_client_from_pci(&vgasr_priv.clients, pdev);
- if (!client)
- ret = VGA_SWITCHEROO_NOT_FOUND;
- else
- ret = client->pwr_state;
- mutex_unlock(&vgasr_mutex);
- return ret;
- }
- EXPORT_SYMBOL(vga_switcheroo_get_client_state);
- /**
- * vga_switcheroo_unregister_client() - unregister client
- * @pdev: client pci device
- *
- * Unregister client. Disable vga_switcheroo if this is a vga client (GPU).
- */
- void vga_switcheroo_unregister_client(struct pci_dev *pdev)
- {
- struct vga_switcheroo_client *client;
- mutex_lock(&vgasr_mutex);
- client = find_client_from_pci(&vgasr_priv.clients, pdev);
- if (client) {
- if (client_is_vga(client))
- vgasr_priv.registered_clients--;
- list_del(&client->list);
- kfree(client);
- }
- if (vgasr_priv.active && vgasr_priv.registered_clients < 2) {
- pr_info("disabled\n");
- vga_switcheroo_debugfs_fini(&vgasr_priv);
- vgasr_priv.active = false;
- }
- mutex_unlock(&vgasr_mutex);
- }
- EXPORT_SYMBOL(vga_switcheroo_unregister_client);
- /**
- * vga_switcheroo_client_fb_set() - set framebuffer of a given client
- * @pdev: client pci device
- * @info: framebuffer
- *
- * Set framebuffer of a given client. The console will be remapped to this
- * on switching.
- */
- void vga_switcheroo_client_fb_set(struct pci_dev *pdev,
- struct fb_info *info)
- {
- struct vga_switcheroo_client *client;
- mutex_lock(&vgasr_mutex);
- client = find_client_from_pci(&vgasr_priv.clients, pdev);
- if (client)
- client->fb_info = info;
- mutex_unlock(&vgasr_mutex);
- }
- EXPORT_SYMBOL(vga_switcheroo_client_fb_set);
- /**
- * DOC: Manual switching and manual power control
- *
- * In this mode of use, the file /sys/kernel/debug/vgaswitcheroo/switch
- * can be read to retrieve the current vga_switcheroo state and commands
- * can be written to it to change the state. The file appears as soon as
- * two GPU drivers and one handler have registered with vga_switcheroo.
- * The following commands are understood:
- *
- * * OFF: Power off the device not in use.
- * * ON: Power on the device not in use.
- * * IGD: Switch to the integrated graphics device.
- * Power on the integrated GPU if necessary, power off the discrete GPU.
- * Prerequisite is that no user space processes (e.g. Xorg, alsactl)
- * have opened device files of the GPUs or the audio client. If the
- * switch fails, the user may invoke lsof(8) or fuser(1) on /dev/dri/
- * and /dev/snd/controlC1 to identify processes blocking the switch.
- * * DIS: Switch to the discrete graphics device.
- * * DIGD: Delayed switch to the integrated graphics device.
- * This will perform the switch once the last user space process has
- * closed the device files of the GPUs and the audio client.
- * * DDIS: Delayed switch to the discrete graphics device.
- * * MIGD: Mux-only switch to the integrated graphics device.
- * Does not remap console or change the power state of either gpu.
- * If the integrated GPU is currently off, the screen will turn black.
- * If it is on, the screen will show whatever happens to be in VRAM.
- * Either way, the user has to blindly enter the command to switch back.
- * * MDIS: Mux-only switch to the discrete graphics device.
- *
- * For GPUs whose power state is controlled by the driver's runtime pm,
- * the ON and OFF commands are a no-op (see next section).
- *
- * For muxless machines, the IGD/DIS, DIGD/DDIS and MIGD/MDIS commands
- * should not be used.
- */
- static int vga_switcheroo_show(struct seq_file *m, void *v)
- {
- struct vga_switcheroo_client *client;
- int i = 0;
- mutex_lock(&vgasr_mutex);
- list_for_each_entry(client, &vgasr_priv.clients, list) {
- seq_printf(m, "%d:%s%s:%c:%s%s:%s\n", i,
- client_id(client) == VGA_SWITCHEROO_DIS ? "DIS" :
- "IGD",
- client_is_vga(client) ? "" : "-Audio",
- client->active ? '+' : ' ',
- client->driver_power_control ? "Dyn" : "",
- client->pwr_state ? "Pwr" : "Off",
- pci_name(client->pdev));
- i++;
- }
- mutex_unlock(&vgasr_mutex);
- return 0;
- }
- static int vga_switcheroo_debugfs_open(struct inode *inode, struct file *file)
- {
- return single_open(file, vga_switcheroo_show, NULL);
- }
- static int vga_switchon(struct vga_switcheroo_client *client)
- {
- if (client->driver_power_control)
- return 0;
- if (vgasr_priv.handler->power_state)
- vgasr_priv.handler->power_state(client->id, VGA_SWITCHEROO_ON);
- /* call the driver callback to turn on device */
- client->ops->set_gpu_state(client->pdev, VGA_SWITCHEROO_ON);
- client->pwr_state = VGA_SWITCHEROO_ON;
- return 0;
- }
- static int vga_switchoff(struct vga_switcheroo_client *client)
- {
- if (client->driver_power_control)
- return 0;
- /* call the driver callback to turn off device */
- client->ops->set_gpu_state(client->pdev, VGA_SWITCHEROO_OFF);
- if (vgasr_priv.handler->power_state)
- vgasr_priv.handler->power_state(client->id, VGA_SWITCHEROO_OFF);
- client->pwr_state = VGA_SWITCHEROO_OFF;
- return 0;
- }
- static void set_audio_state(enum vga_switcheroo_client_id id,
- enum vga_switcheroo_state state)
- {
- struct vga_switcheroo_client *client;
- client = find_client_from_id(&vgasr_priv.clients, id | ID_BIT_AUDIO);
- if (client && client->pwr_state != state) {
- client->ops->set_gpu_state(client->pdev, state);
- client->pwr_state = state;
- }
- }
- /* stage one happens before delay */
- static int vga_switchto_stage1(struct vga_switcheroo_client *new_client)
- {
- struct vga_switcheroo_client *active;
- active = find_active_client(&vgasr_priv.clients);
- if (!active)
- return 0;
- if (new_client->pwr_state == VGA_SWITCHEROO_OFF)
- vga_switchon(new_client);
- vga_set_default_device(new_client->pdev);
- return 0;
- }
- /* post delay */
- static int vga_switchto_stage2(struct vga_switcheroo_client *new_client)
- {
- int ret;
- struct vga_switcheroo_client *active;
- active = find_active_client(&vgasr_priv.clients);
- if (!active)
- return 0;
- active->active = false;
- set_audio_state(active->id, VGA_SWITCHEROO_OFF);
- if (new_client->fb_info) {
- struct fb_event event;
- console_lock();
- event.info = new_client->fb_info;
- fb_notifier_call_chain(FB_EVENT_REMAP_ALL_CONSOLE, &event);
- console_unlock();
- }
- ret = vgasr_priv.handler->switchto(new_client->id);
- if (ret)
- return ret;
- if (new_client->ops->reprobe)
- new_client->ops->reprobe(new_client->pdev);
- if (active->pwr_state == VGA_SWITCHEROO_ON)
- vga_switchoff(active);
- set_audio_state(new_client->id, VGA_SWITCHEROO_ON);
- new_client->active = true;
- return 0;
- }
- static bool check_can_switch(void)
- {
- struct vga_switcheroo_client *client;
- list_for_each_entry(client, &vgasr_priv.clients, list) {
- if (!client->ops->can_switch(client->pdev)) {
- pr_err("client %x refused switch\n", client->id);
- return false;
- }
- }
- return true;
- }
- static ssize_t
- vga_switcheroo_debugfs_write(struct file *filp, const char __user *ubuf,
- size_t cnt, loff_t *ppos)
- {
- char usercmd[64];
- int ret;
- bool delay = false, can_switch;
- bool just_mux = false;
- enum vga_switcheroo_client_id client_id = VGA_SWITCHEROO_UNKNOWN_ID;
- struct vga_switcheroo_client *client = NULL;
- if (cnt > 63)
- cnt = 63;
- if (copy_from_user(usercmd, ubuf, cnt))
- return -EFAULT;
- mutex_lock(&vgasr_mutex);
- if (!vgasr_priv.active) {
- cnt = -EINVAL;
- goto out;
- }
- /* pwr off the device not in use */
- if (strncmp(usercmd, "OFF", 3) == 0) {
- list_for_each_entry(client, &vgasr_priv.clients, list) {
- if (client->active || client_is_audio(client))
- continue;
- if (client->driver_power_control)
- continue;
- set_audio_state(client->id, VGA_SWITCHEROO_OFF);
- if (client->pwr_state == VGA_SWITCHEROO_ON)
- vga_switchoff(client);
- }
- goto out;
- }
- /* pwr on the device not in use */
- if (strncmp(usercmd, "ON", 2) == 0) {
- list_for_each_entry(client, &vgasr_priv.clients, list) {
- if (client->active || client_is_audio(client))
- continue;
- if (client->driver_power_control)
- continue;
- if (client->pwr_state == VGA_SWITCHEROO_OFF)
- vga_switchon(client);
- set_audio_state(client->id, VGA_SWITCHEROO_ON);
- }
- goto out;
- }
- /* request a delayed switch - test can we switch now */
- if (strncmp(usercmd, "DIGD", 4) == 0) {
- client_id = VGA_SWITCHEROO_IGD;
- delay = true;
- }
- if (strncmp(usercmd, "DDIS", 4) == 0) {
- client_id = VGA_SWITCHEROO_DIS;
- delay = true;
- }
- if (strncmp(usercmd, "IGD", 3) == 0)
- client_id = VGA_SWITCHEROO_IGD;
- if (strncmp(usercmd, "DIS", 3) == 0)
- client_id = VGA_SWITCHEROO_DIS;
- if (strncmp(usercmd, "MIGD", 4) == 0) {
- just_mux = true;
- client_id = VGA_SWITCHEROO_IGD;
- }
- if (strncmp(usercmd, "MDIS", 4) == 0) {
- just_mux = true;
- client_id = VGA_SWITCHEROO_DIS;
- }
- if (client_id == VGA_SWITCHEROO_UNKNOWN_ID)
- goto out;
- client = find_client_from_id(&vgasr_priv.clients, client_id);
- if (!client)
- goto out;
- vgasr_priv.delayed_switch_active = false;
- if (just_mux) {
- ret = vgasr_priv.handler->switchto(client_id);
- goto out;
- }
- if (client->active)
- goto out;
- /* okay we want a switch - test if devices are willing to switch */
- can_switch = check_can_switch();
- if (can_switch == false && delay == false)
- goto out;
- if (can_switch) {
- ret = vga_switchto_stage1(client);
- if (ret)
- pr_err("switching failed stage 1 %d\n", ret);
- ret = vga_switchto_stage2(client);
- if (ret)
- pr_err("switching failed stage 2 %d\n", ret);
- } else {
- pr_info("setting delayed switch to client %d\n", client->id);
- vgasr_priv.delayed_switch_active = true;
- vgasr_priv.delayed_client_id = client_id;
- ret = vga_switchto_stage1(client);
- if (ret)
- pr_err("delayed switching stage 1 failed %d\n", ret);
- }
- out:
- mutex_unlock(&vgasr_mutex);
- return cnt;
- }
- static const struct file_operations vga_switcheroo_debugfs_fops = {
- .owner = THIS_MODULE,
- .open = vga_switcheroo_debugfs_open,
- .write = vga_switcheroo_debugfs_write,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = single_release,
- };
- static void vga_switcheroo_debugfs_fini(struct vgasr_priv *priv)
- {
- debugfs_remove(priv->switch_file);
- priv->switch_file = NULL;
- debugfs_remove(priv->debugfs_root);
- priv->debugfs_root = NULL;
- }
- static int vga_switcheroo_debugfs_init(struct vgasr_priv *priv)
- {
- static const char mp[] = "/sys/kernel/debug";
- /* already initialised */
- if (priv->debugfs_root)
- return 0;
- priv->debugfs_root = debugfs_create_dir("vgaswitcheroo", NULL);
- if (!priv->debugfs_root) {
- pr_err("Cannot create %s/vgaswitcheroo\n", mp);
- goto fail;
- }
- priv->switch_file = debugfs_create_file("switch", 0644,
- priv->debugfs_root, NULL,
- &vga_switcheroo_debugfs_fops);
- if (!priv->switch_file) {
- pr_err("cannot create %s/vgaswitcheroo/switch\n", mp);
- goto fail;
- }
- return 0;
- fail:
- vga_switcheroo_debugfs_fini(priv);
- return -1;
- }
- /**
- * vga_switcheroo_process_delayed_switch() - helper for delayed switching
- *
- * Process a delayed switch if one is pending. DRM drivers should call this
- * from their ->lastclose callback.
- *
- * Return: 0 on success. -EINVAL if no delayed switch is pending, if the client
- * has unregistered in the meantime or if there are other clients blocking the
- * switch. If the actual switch fails, an error is reported and 0 is returned.
- */
- int vga_switcheroo_process_delayed_switch(void)
- {
- struct vga_switcheroo_client *client;
- int ret;
- int err = -EINVAL;
- mutex_lock(&vgasr_mutex);
- if (!vgasr_priv.delayed_switch_active)
- goto err;
- pr_info("processing delayed switch to %d\n",
- vgasr_priv.delayed_client_id);
- client = find_client_from_id(&vgasr_priv.clients,
- vgasr_priv.delayed_client_id);
- if (!client || !check_can_switch())
- goto err;
- ret = vga_switchto_stage2(client);
- if (ret)
- pr_err("delayed switching failed stage 2 %d\n", ret);
- vgasr_priv.delayed_switch_active = false;
- err = 0;
- err:
- mutex_unlock(&vgasr_mutex);
- return err;
- }
- EXPORT_SYMBOL(vga_switcheroo_process_delayed_switch);
- /**
- * DOC: Driver power control
- *
- * In this mode of use, the discrete GPU automatically powers up and down at
- * the discretion of the driver's runtime pm. On muxed machines, the user may
- * still influence the muxer state by way of the debugfs interface, however
- * the ON and OFF commands become a no-op for the discrete GPU.
- *
- * This mode is the default on Nvidia HybridPower/Optimus and ATI PowerXpress.
- * Specifying nouveau.runpm=0, radeon.runpm=0 or amdgpu.runpm=0 on the kernel
- * command line disables it.
- *
- * When the driver decides to power up or down, it notifies vga_switcheroo
- * thereof so that it can (a) power the audio device on the GPU up or down,
- * and (b) update its internal power state representation for the device.
- * This is achieved by vga_switcheroo_set_dynamic_switch().
- *
- * After the GPU has been suspended, the handler needs to be called to cut
- * power to the GPU. Likewise it needs to reinstate power before the GPU
- * can resume. This is achieved by vga_switcheroo_init_domain_pm_ops(),
- * which augments the GPU's suspend/resume functions by the requisite
- * calls to the handler.
- *
- * When the audio device resumes, the GPU needs to be woken. This is achieved
- * by vga_switcheroo_init_domain_pm_optimus_hdmi_audio(), which augments the
- * audio device's resume function.
- *
- * On muxed machines, if the mux is initially switched to the discrete GPU,
- * the user ends up with a black screen when the GPU powers down after boot.
- * As a workaround, the mux is forced to the integrated GPU on runtime suspend,
- * cf. https://bugs.freedesktop.org/show_bug.cgi?id=75917
- */
- static void vga_switcheroo_power_switch(struct pci_dev *pdev,
- enum vga_switcheroo_state state)
- {
- struct vga_switcheroo_client *client;
- if (!vgasr_priv.handler->power_state)
- return;
- client = find_client_from_pci(&vgasr_priv.clients, pdev);
- if (!client)
- return;
- if (!client->driver_power_control)
- return;
- vgasr_priv.handler->power_state(client->id, state);
- }
- /**
- * vga_switcheroo_set_dynamic_switch() - helper for driver power control
- * @pdev: client pci device
- * @dynamic: new power state
- *
- * Helper for GPUs whose power state is controlled by the driver's runtime pm.
- * When the driver decides to power up or down, it notifies vga_switcheroo
- * thereof using this helper so that it can (a) power the audio device on
- * the GPU up or down, and (b) update its internal power state representation
- * for the device.
- */
- void vga_switcheroo_set_dynamic_switch(struct pci_dev *pdev,
- enum vga_switcheroo_state dynamic)
- {
- struct vga_switcheroo_client *client;
- mutex_lock(&vgasr_mutex);
- client = find_client_from_pci(&vgasr_priv.clients, pdev);
- if (!client || !client->driver_power_control) {
- mutex_unlock(&vgasr_mutex);
- return;
- }
- client->pwr_state = dynamic;
- set_audio_state(client->id, dynamic);
- mutex_unlock(&vgasr_mutex);
- }
- EXPORT_SYMBOL(vga_switcheroo_set_dynamic_switch);
- /* switcheroo power domain */
- static int vga_switcheroo_runtime_suspend(struct device *dev)
- {
- struct pci_dev *pdev = to_pci_dev(dev);
- int ret;
- ret = dev->bus->pm->runtime_suspend(dev);
- if (ret)
- return ret;
- mutex_lock(&vgasr_mutex);
- if (vgasr_priv.handler->switchto)
- vgasr_priv.handler->switchto(VGA_SWITCHEROO_IGD);
- vga_switcheroo_power_switch(pdev, VGA_SWITCHEROO_OFF);
- mutex_unlock(&vgasr_mutex);
- return 0;
- }
- static int vga_switcheroo_runtime_resume(struct device *dev)
- {
- struct pci_dev *pdev = to_pci_dev(dev);
- int ret;
- mutex_lock(&vgasr_mutex);
- vga_switcheroo_power_switch(pdev, VGA_SWITCHEROO_ON);
- mutex_unlock(&vgasr_mutex);
- ret = dev->bus->pm->runtime_resume(dev);
- if (ret)
- return ret;
- return 0;
- }
- /**
- * vga_switcheroo_init_domain_pm_ops() - helper for driver power control
- * @dev: vga client device
- * @domain: power domain
- *
- * Helper for GPUs whose power state is controlled by the driver's runtime pm.
- * After the GPU has been suspended, the handler needs to be called to cut
- * power to the GPU. Likewise it needs to reinstate power before the GPU
- * can resume. To this end, this helper augments the suspend/resume functions
- * by the requisite calls to the handler. It needs only be called on platforms
- * where the power switch is separate to the device being powered down.
- */
- int vga_switcheroo_init_domain_pm_ops(struct device *dev,
- struct dev_pm_domain *domain)
- {
- /* copy over all the bus versions */
- if (dev->bus && dev->bus->pm) {
- domain->ops = *dev->bus->pm;
- domain->ops.runtime_suspend = vga_switcheroo_runtime_suspend;
- domain->ops.runtime_resume = vga_switcheroo_runtime_resume;
- dev->pm_domain = domain;
- return 0;
- }
- dev->pm_domain = NULL;
- return -EINVAL;
- }
- EXPORT_SYMBOL(vga_switcheroo_init_domain_pm_ops);
- void vga_switcheroo_fini_domain_pm_ops(struct device *dev)
- {
- dev->pm_domain = NULL;
- }
- EXPORT_SYMBOL(vga_switcheroo_fini_domain_pm_ops);
- static int vga_switcheroo_runtime_resume_hdmi_audio(struct device *dev)
- {
- struct pci_dev *pdev = to_pci_dev(dev);
- struct vga_switcheroo_client *client;
- struct device *video_dev = NULL;
- int ret;
- /* we need to check if we have to switch back on the video
- device so the audio device can come back */
- mutex_lock(&vgasr_mutex);
- list_for_each_entry(client, &vgasr_priv.clients, list) {
- if (PCI_SLOT(client->pdev->devfn) == PCI_SLOT(pdev->devfn) &&
- client_is_vga(client)) {
- video_dev = &client->pdev->dev;
- break;
- }
- }
- mutex_unlock(&vgasr_mutex);
- if (video_dev) {
- ret = pm_runtime_get_sync(video_dev);
- if (ret && ret != 1)
- return ret;
- }
- ret = dev->bus->pm->runtime_resume(dev);
- /* put the reference for the gpu */
- if (video_dev) {
- pm_runtime_mark_last_busy(video_dev);
- pm_runtime_put_autosuspend(video_dev);
- }
- return ret;
- }
- /**
- * vga_switcheroo_init_domain_pm_optimus_hdmi_audio() - helper for driver
- * power control
- * @dev: audio client device
- * @domain: power domain
- *
- * Helper for GPUs whose power state is controlled by the driver's runtime pm.
- * When the audio device resumes, the GPU needs to be woken. This helper
- * augments the audio device's resume function to do that.
- *
- * Return: 0 on success, -EINVAL if no power management operations are
- * defined for this device.
- */
- int
- vga_switcheroo_init_domain_pm_optimus_hdmi_audio(struct device *dev,
- struct dev_pm_domain *domain)
- {
- /* copy over all the bus versions */
- if (dev->bus && dev->bus->pm) {
- domain->ops = *dev->bus->pm;
- domain->ops.runtime_resume =
- vga_switcheroo_runtime_resume_hdmi_audio;
- dev->pm_domain = domain;
- return 0;
- }
- dev->pm_domain = NULL;
- return -EINVAL;
- }
- EXPORT_SYMBOL(vga_switcheroo_init_domain_pm_optimus_hdmi_audio);
|