/drivers/gpu/vga/vga_switcheroo.c
C | 573 lines | 450 code | 93 blank | 30 comment | 94 complexity | f93a6b53b1f0f4d6de88db2240294b42 MD5 | raw file
- /*
- * Copyright (c) 2010 Red Hat Inc.
- * Author : Dave Airlie <airlied@redhat.com>
- *
- *
- * Licensed under GPLv2
- *
- * vga_switcheroo.c - Support for laptop with dual GPU using one set of outputs
- Switcher interface - methods require for ATPX and DCM
- - switchto - this throws the output MUX switch
- - discrete_set_power - sets the power state for the discrete card
- GPU driver interface
- - set_gpu_state - this should do the equiv of s/r for the card
- - this should *not* set the discrete power state
- - switch_check - check if the device is in a position to switch now
- */
- #include <linux/module.h>
- #include <linux/dmi.h>
- #include <linux/seq_file.h>
- #include <linux/uaccess.h>
- #include <linux/fs.h>
- #include <linux/debugfs.h>
- #include <linux/fb.h>
- #include <linux/pci.h>
- #include <linux/console.h>
- #include <linux/vga_switcheroo.h>
- #include <linux/vgaarb.h>
- struct vga_switcheroo_client {
- struct pci_dev *pdev;
- struct fb_info *fb_info;
- int pwr_state;
- const struct vga_switcheroo_client_ops *ops;
- int id;
- bool active;
- struct list_head list;
- };
- static DEFINE_MUTEX(vgasr_mutex);
- 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;
- 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 == -1 || !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 != -1)
- 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;
- }
- int vga_switcheroo_register_handler(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()) {
- printk(KERN_INFO "vga_switcheroo: enabled\n");
- vga_switcheroo_enable();
- }
- mutex_unlock(&vgasr_mutex);
- return 0;
- }
- EXPORT_SYMBOL(vga_switcheroo_register_handler);
- void vga_switcheroo_unregister_handler(void)
- {
- mutex_lock(&vgasr_mutex);
- vgasr_priv.handler = NULL;
- if (vgasr_priv.active) {
- pr_info("vga_switcheroo: 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,
- int id, bool active)
- {
- 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;
- 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()) {
- printk(KERN_INFO "vga_switcheroo: enabled\n");
- vga_switcheroo_enable();
- }
- mutex_unlock(&vgasr_mutex);
- return 0;
- }
- int vga_switcheroo_register_client(struct pci_dev *pdev,
- const struct vga_switcheroo_client_ops *ops)
- {
- return register_client(pdev, ops, -1,
- pdev == vga_default_device());
- }
- EXPORT_SYMBOL(vga_switcheroo_register_client);
- int vga_switcheroo_register_audio_client(struct pci_dev *pdev,
- const struct vga_switcheroo_client_ops *ops,
- int id, bool active)
- {
- return register_client(pdev, ops, id | ID_BIT_AUDIO, active);
- }
- 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, int 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 && client_is_vga(client))
- return client;
- return NULL;
- }
- int vga_switcheroo_get_client_state(struct pci_dev *pdev)
- {
- struct vga_switcheroo_client *client;
- client = find_client_from_pci(&vgasr_priv.clients, pdev);
- if (!client)
- return VGA_SWITCHEROO_NOT_FOUND;
- if (!vgasr_priv.active)
- return VGA_SWITCHEROO_INIT;
- return client->pwr_state;
- }
- EXPORT_SYMBOL(vga_switcheroo_get_client_state);
- 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) {
- printk(KERN_INFO "vga_switcheroo: disabled\n");
- vga_switcheroo_debugfs_fini(&vgasr_priv);
- vgasr_priv.active = false;
- }
- mutex_unlock(&vgasr_mutex);
- }
- EXPORT_SYMBOL(vga_switcheroo_unregister_client);
- 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);
- 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\n", i,
- client_id(client) == VGA_SWITCHEROO_DIS ? "DIS" : "IGD",
- client_is_vga(client) ? "" : "-Audio",
- client->active ? '+' : ' ',
- 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 (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)
- {
- /* 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(int id, int 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)) {
- printk(KERN_ERR "vga_switcheroo: 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];
- const char *pdev_name;
- int ret;
- bool delay = false, can_switch;
- bool just_mux = false;
- int client_id = -1;
- 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;
- 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->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 == -1)
- 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) {
- pdev_name = pci_name(client->pdev);
- ret = vga_switchto_stage1(client);
- if (ret)
- printk(KERN_ERR "vga_switcheroo: switching failed stage 1 %d\n", ret);
- ret = vga_switchto_stage2(client);
- if (ret)
- printk(KERN_ERR "vga_switcheroo: switching failed stage 2 %d\n", ret);
- } else {
- printk(KERN_INFO "vga_switcheroo: 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)
- printk(KERN_ERR "vga_switcheroo: 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)
- {
- if (priv->switch_file) {
- debugfs_remove(priv->switch_file);
- priv->switch_file = NULL;
- }
- if (priv->debugfs_root) {
- debugfs_remove(priv->debugfs_root);
- priv->debugfs_root = NULL;
- }
- }
- static int vga_switcheroo_debugfs_init(struct vgasr_priv *priv)
- {
- /* already initialised */
- if (priv->debugfs_root)
- return 0;
- priv->debugfs_root = debugfs_create_dir("vgaswitcheroo", NULL);
- if (!priv->debugfs_root) {
- printk(KERN_ERR "vga_switcheroo: Cannot create /sys/kernel/debug/vgaswitcheroo\n");
- goto fail;
- }
- priv->switch_file = debugfs_create_file("switch", 0644,
- priv->debugfs_root, NULL, &vga_switcheroo_debugfs_fops);
- if (!priv->switch_file) {
- printk(KERN_ERR "vga_switcheroo: cannot create /sys/kernel/debug/vgaswitcheroo/switch\n");
- goto fail;
- }
- return 0;
- fail:
- vga_switcheroo_debugfs_fini(priv);
- return -1;
- }
- int vga_switcheroo_process_delayed_switch(void)
- {
- struct vga_switcheroo_client *client;
- const char *pdev_name;
- int ret;
- int err = -EINVAL;
- mutex_lock(&vgasr_mutex);
- if (!vgasr_priv.delayed_switch_active)
- goto err;
- printk(KERN_INFO "vga_switcheroo: 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;
- pdev_name = pci_name(client->pdev);
- ret = vga_switchto_stage2(client);
- if (ret)
- printk(KERN_ERR "vga_switcheroo: 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);