Merge tag 'gpio-v3.13-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw...
[linux-2.6.git] / drivers / gpu / vga / vga_switcheroo.c
blobec0ae2d1686a3150c03403fa42524aca2111afa4
1 /*
2 * Copyright (c) 2010 Red Hat Inc.
3 * Author : Dave Airlie <airlied@redhat.com>
6 * Licensed under GPLv2
8 * vga_switcheroo.c - Support for laptop with dual GPU using one set of outputs
10 Switcher interface - methods require for ATPX and DCM
11 - switchto - this throws the output MUX switch
12 - discrete_set_power - sets the power state for the discrete card
14 GPU driver interface
15 - set_gpu_state - this should do the equiv of s/r for the card
16 - this should *not* set the discrete power state
17 - switch_check - check if the device is in a position to switch now
20 #include <linux/module.h>
21 #include <linux/seq_file.h>
22 #include <linux/uaccess.h>
23 #include <linux/fs.h>
24 #include <linux/debugfs.h>
25 #include <linux/fb.h>
27 #include <linux/pci.h>
28 #include <linux/console.h>
29 #include <linux/vga_switcheroo.h>
30 #include <linux/pm_runtime.h>
32 #include <linux/vgaarb.h>
34 struct vga_switcheroo_client {
35 struct pci_dev *pdev;
36 struct fb_info *fb_info;
37 int pwr_state;
38 const struct vga_switcheroo_client_ops *ops;
39 int id;
40 bool active;
41 bool driver_power_control;
42 struct list_head list;
45 static DEFINE_MUTEX(vgasr_mutex);
47 struct vgasr_priv {
49 bool active;
50 bool delayed_switch_active;
51 enum vga_switcheroo_client_id delayed_client_id;
53 struct dentry *debugfs_root;
54 struct dentry *switch_file;
56 int registered_clients;
57 struct list_head clients;
59 struct vga_switcheroo_handler *handler;
62 #define ID_BIT_AUDIO 0x100
63 #define client_is_audio(c) ((c)->id & ID_BIT_AUDIO)
64 #define client_is_vga(c) ((c)->id == -1 || !client_is_audio(c))
65 #define client_id(c) ((c)->id & ~ID_BIT_AUDIO)
67 static int vga_switcheroo_debugfs_init(struct vgasr_priv *priv);
68 static void vga_switcheroo_debugfs_fini(struct vgasr_priv *priv);
70 /* only one switcheroo per system */
71 static struct vgasr_priv vgasr_priv = {
72 .clients = LIST_HEAD_INIT(vgasr_priv.clients),
75 static bool vga_switcheroo_ready(void)
77 /* we're ready if we get two clients + handler */
78 return !vgasr_priv.active &&
79 vgasr_priv.registered_clients == 2 && vgasr_priv.handler;
82 static void vga_switcheroo_enable(void)
84 int ret;
85 struct vga_switcheroo_client *client;
87 /* call the handler to init */
88 if (vgasr_priv.handler->init)
89 vgasr_priv.handler->init();
91 list_for_each_entry(client, &vgasr_priv.clients, list) {
92 if (client->id != -1)
93 continue;
94 ret = vgasr_priv.handler->get_client_id(client->pdev);
95 if (ret < 0)
96 return;
98 client->id = ret;
100 vga_switcheroo_debugfs_init(&vgasr_priv);
101 vgasr_priv.active = true;
104 int vga_switcheroo_register_handler(struct vga_switcheroo_handler *handler)
106 mutex_lock(&vgasr_mutex);
107 if (vgasr_priv.handler) {
108 mutex_unlock(&vgasr_mutex);
109 return -EINVAL;
112 vgasr_priv.handler = handler;
113 if (vga_switcheroo_ready()) {
114 printk(KERN_INFO "vga_switcheroo: enabled\n");
115 vga_switcheroo_enable();
117 mutex_unlock(&vgasr_mutex);
118 return 0;
120 EXPORT_SYMBOL(vga_switcheroo_register_handler);
122 void vga_switcheroo_unregister_handler(void)
124 mutex_lock(&vgasr_mutex);
125 vgasr_priv.handler = NULL;
126 if (vgasr_priv.active) {
127 pr_info("vga_switcheroo: disabled\n");
128 vga_switcheroo_debugfs_fini(&vgasr_priv);
129 vgasr_priv.active = false;
131 mutex_unlock(&vgasr_mutex);
133 EXPORT_SYMBOL(vga_switcheroo_unregister_handler);
135 static int register_client(struct pci_dev *pdev,
136 const struct vga_switcheroo_client_ops *ops,
137 int id, bool active, bool driver_power_control)
139 struct vga_switcheroo_client *client;
141 client = kzalloc(sizeof(*client), GFP_KERNEL);
142 if (!client)
143 return -ENOMEM;
145 client->pwr_state = VGA_SWITCHEROO_ON;
146 client->pdev = pdev;
147 client->ops = ops;
148 client->id = id;
149 client->active = active;
150 client->driver_power_control = driver_power_control;
152 mutex_lock(&vgasr_mutex);
153 list_add_tail(&client->list, &vgasr_priv.clients);
154 if (client_is_vga(client))
155 vgasr_priv.registered_clients++;
157 if (vga_switcheroo_ready()) {
158 printk(KERN_INFO "vga_switcheroo: enabled\n");
159 vga_switcheroo_enable();
161 mutex_unlock(&vgasr_mutex);
162 return 0;
165 int vga_switcheroo_register_client(struct pci_dev *pdev,
166 const struct vga_switcheroo_client_ops *ops,
167 bool driver_power_control)
169 return register_client(pdev, ops, -1,
170 pdev == vga_default_device(), driver_power_control);
172 EXPORT_SYMBOL(vga_switcheroo_register_client);
174 int vga_switcheroo_register_audio_client(struct pci_dev *pdev,
175 const struct vga_switcheroo_client_ops *ops,
176 int id, bool active)
178 return register_client(pdev, ops, id | ID_BIT_AUDIO, active, false);
180 EXPORT_SYMBOL(vga_switcheroo_register_audio_client);
182 static struct vga_switcheroo_client *
183 find_client_from_pci(struct list_head *head, struct pci_dev *pdev)
185 struct vga_switcheroo_client *client;
186 list_for_each_entry(client, head, list)
187 if (client->pdev == pdev)
188 return client;
189 return NULL;
192 static struct vga_switcheroo_client *
193 find_client_from_id(struct list_head *head, int client_id)
195 struct vga_switcheroo_client *client;
196 list_for_each_entry(client, head, list)
197 if (client->id == client_id)
198 return client;
199 return NULL;
202 static struct vga_switcheroo_client *
203 find_active_client(struct list_head *head)
205 struct vga_switcheroo_client *client;
206 list_for_each_entry(client, head, list)
207 if (client->active && client_is_vga(client))
208 return client;
209 return NULL;
212 int vga_switcheroo_get_client_state(struct pci_dev *pdev)
214 struct vga_switcheroo_client *client;
216 client = find_client_from_pci(&vgasr_priv.clients, pdev);
217 if (!client)
218 return VGA_SWITCHEROO_NOT_FOUND;
219 if (!vgasr_priv.active)
220 return VGA_SWITCHEROO_INIT;
221 return client->pwr_state;
223 EXPORT_SYMBOL(vga_switcheroo_get_client_state);
225 void vga_switcheroo_unregister_client(struct pci_dev *pdev)
227 struct vga_switcheroo_client *client;
229 mutex_lock(&vgasr_mutex);
230 client = find_client_from_pci(&vgasr_priv.clients, pdev);
231 if (client) {
232 if (client_is_vga(client))
233 vgasr_priv.registered_clients--;
234 list_del(&client->list);
235 kfree(client);
237 if (vgasr_priv.active && vgasr_priv.registered_clients < 2) {
238 printk(KERN_INFO "vga_switcheroo: disabled\n");
239 vga_switcheroo_debugfs_fini(&vgasr_priv);
240 vgasr_priv.active = false;
242 mutex_unlock(&vgasr_mutex);
244 EXPORT_SYMBOL(vga_switcheroo_unregister_client);
246 void vga_switcheroo_client_fb_set(struct pci_dev *pdev,
247 struct fb_info *info)
249 struct vga_switcheroo_client *client;
251 mutex_lock(&vgasr_mutex);
252 client = find_client_from_pci(&vgasr_priv.clients, pdev);
253 if (client)
254 client->fb_info = info;
255 mutex_unlock(&vgasr_mutex);
257 EXPORT_SYMBOL(vga_switcheroo_client_fb_set);
259 static int vga_switcheroo_show(struct seq_file *m, void *v)
261 struct vga_switcheroo_client *client;
262 int i = 0;
263 mutex_lock(&vgasr_mutex);
264 list_for_each_entry(client, &vgasr_priv.clients, list) {
265 seq_printf(m, "%d:%s%s:%c:%s%s:%s\n", i,
266 client_id(client) == VGA_SWITCHEROO_DIS ? "DIS" : "IGD",
267 client_is_vga(client) ? "" : "-Audio",
268 client->active ? '+' : ' ',
269 client->driver_power_control ? "Dyn" : "",
270 client->pwr_state ? "Pwr" : "Off",
271 pci_name(client->pdev));
272 i++;
274 mutex_unlock(&vgasr_mutex);
275 return 0;
278 static int vga_switcheroo_debugfs_open(struct inode *inode, struct file *file)
280 return single_open(file, vga_switcheroo_show, NULL);
283 static int vga_switchon(struct vga_switcheroo_client *client)
285 if (client->driver_power_control)
286 return 0;
287 if (vgasr_priv.handler->power_state)
288 vgasr_priv.handler->power_state(client->id, VGA_SWITCHEROO_ON);
289 /* call the driver callback to turn on device */
290 client->ops->set_gpu_state(client->pdev, VGA_SWITCHEROO_ON);
291 client->pwr_state = VGA_SWITCHEROO_ON;
292 return 0;
295 static int vga_switchoff(struct vga_switcheroo_client *client)
297 if (client->driver_power_control)
298 return 0;
299 /* call the driver callback to turn off device */
300 client->ops->set_gpu_state(client->pdev, VGA_SWITCHEROO_OFF);
301 if (vgasr_priv.handler->power_state)
302 vgasr_priv.handler->power_state(client->id, VGA_SWITCHEROO_OFF);
303 client->pwr_state = VGA_SWITCHEROO_OFF;
304 return 0;
307 static void set_audio_state(int id, int state)
309 struct vga_switcheroo_client *client;
311 client = find_client_from_id(&vgasr_priv.clients, id | ID_BIT_AUDIO);
312 if (client && client->pwr_state != state) {
313 client->ops->set_gpu_state(client->pdev, state);
314 client->pwr_state = state;
318 /* stage one happens before delay */
319 static int vga_switchto_stage1(struct vga_switcheroo_client *new_client)
321 struct vga_switcheroo_client *active;
323 active = find_active_client(&vgasr_priv.clients);
324 if (!active)
325 return 0;
327 if (new_client->pwr_state == VGA_SWITCHEROO_OFF)
328 vga_switchon(new_client);
330 vga_set_default_device(new_client->pdev);
331 return 0;
334 /* post delay */
335 static int vga_switchto_stage2(struct vga_switcheroo_client *new_client)
337 int ret;
338 struct vga_switcheroo_client *active;
340 active = find_active_client(&vgasr_priv.clients);
341 if (!active)
342 return 0;
344 active->active = false;
346 set_audio_state(active->id, VGA_SWITCHEROO_OFF);
348 if (new_client->fb_info) {
349 struct fb_event event;
350 console_lock();
351 event.info = new_client->fb_info;
352 fb_notifier_call_chain(FB_EVENT_REMAP_ALL_CONSOLE, &event);
353 console_unlock();
356 ret = vgasr_priv.handler->switchto(new_client->id);
357 if (ret)
358 return ret;
360 if (new_client->ops->reprobe)
361 new_client->ops->reprobe(new_client->pdev);
363 if (active->pwr_state == VGA_SWITCHEROO_ON)
364 vga_switchoff(active);
366 set_audio_state(new_client->id, VGA_SWITCHEROO_ON);
368 new_client->active = true;
369 return 0;
372 static bool check_can_switch(void)
374 struct vga_switcheroo_client *client;
376 list_for_each_entry(client, &vgasr_priv.clients, list) {
377 if (!client->ops->can_switch(client->pdev)) {
378 printk(KERN_ERR "vga_switcheroo: client %x refused switch\n", client->id);
379 return false;
382 return true;
385 static ssize_t
386 vga_switcheroo_debugfs_write(struct file *filp, const char __user *ubuf,
387 size_t cnt, loff_t *ppos)
389 char usercmd[64];
390 int ret;
391 bool delay = false, can_switch;
392 bool just_mux = false;
393 int client_id = -1;
394 struct vga_switcheroo_client *client = NULL;
396 if (cnt > 63)
397 cnt = 63;
399 if (copy_from_user(usercmd, ubuf, cnt))
400 return -EFAULT;
402 mutex_lock(&vgasr_mutex);
404 if (!vgasr_priv.active) {
405 cnt = -EINVAL;
406 goto out;
409 /* pwr off the device not in use */
410 if (strncmp(usercmd, "OFF", 3) == 0) {
411 list_for_each_entry(client, &vgasr_priv.clients, list) {
412 if (client->active || client_is_audio(client))
413 continue;
414 if (client->driver_power_control)
415 continue;
416 set_audio_state(client->id, VGA_SWITCHEROO_OFF);
417 if (client->pwr_state == VGA_SWITCHEROO_ON)
418 vga_switchoff(client);
420 goto out;
422 /* pwr on the device not in use */
423 if (strncmp(usercmd, "ON", 2) == 0) {
424 list_for_each_entry(client, &vgasr_priv.clients, list) {
425 if (client->active || client_is_audio(client))
426 continue;
427 if (client->driver_power_control)
428 continue;
429 if (client->pwr_state == VGA_SWITCHEROO_OFF)
430 vga_switchon(client);
431 set_audio_state(client->id, VGA_SWITCHEROO_ON);
433 goto out;
436 /* request a delayed switch - test can we switch now */
437 if (strncmp(usercmd, "DIGD", 4) == 0) {
438 client_id = VGA_SWITCHEROO_IGD;
439 delay = true;
442 if (strncmp(usercmd, "DDIS", 4) == 0) {
443 client_id = VGA_SWITCHEROO_DIS;
444 delay = true;
447 if (strncmp(usercmd, "IGD", 3) == 0)
448 client_id = VGA_SWITCHEROO_IGD;
450 if (strncmp(usercmd, "DIS", 3) == 0)
451 client_id = VGA_SWITCHEROO_DIS;
453 if (strncmp(usercmd, "MIGD", 4) == 0) {
454 just_mux = true;
455 client_id = VGA_SWITCHEROO_IGD;
457 if (strncmp(usercmd, "MDIS", 4) == 0) {
458 just_mux = true;
459 client_id = VGA_SWITCHEROO_DIS;
462 if (client_id == -1)
463 goto out;
464 client = find_client_from_id(&vgasr_priv.clients, client_id);
465 if (!client)
466 goto out;
468 vgasr_priv.delayed_switch_active = false;
470 if (just_mux) {
471 ret = vgasr_priv.handler->switchto(client_id);
472 goto out;
475 if (client->active)
476 goto out;
478 /* okay we want a switch - test if devices are willing to switch */
479 can_switch = check_can_switch();
481 if (can_switch == false && delay == false)
482 goto out;
484 if (can_switch) {
485 ret = vga_switchto_stage1(client);
486 if (ret)
487 printk(KERN_ERR "vga_switcheroo: switching failed stage 1 %d\n", ret);
489 ret = vga_switchto_stage2(client);
490 if (ret)
491 printk(KERN_ERR "vga_switcheroo: switching failed stage 2 %d\n", ret);
493 } else {
494 printk(KERN_INFO "vga_switcheroo: setting delayed switch to client %d\n", client->id);
495 vgasr_priv.delayed_switch_active = true;
496 vgasr_priv.delayed_client_id = client_id;
498 ret = vga_switchto_stage1(client);
499 if (ret)
500 printk(KERN_ERR "vga_switcheroo: delayed switching stage 1 failed %d\n", ret);
503 out:
504 mutex_unlock(&vgasr_mutex);
505 return cnt;
508 static const struct file_operations vga_switcheroo_debugfs_fops = {
509 .owner = THIS_MODULE,
510 .open = vga_switcheroo_debugfs_open,
511 .write = vga_switcheroo_debugfs_write,
512 .read = seq_read,
513 .llseek = seq_lseek,
514 .release = single_release,
517 static void vga_switcheroo_debugfs_fini(struct vgasr_priv *priv)
519 if (priv->switch_file) {
520 debugfs_remove(priv->switch_file);
521 priv->switch_file = NULL;
523 if (priv->debugfs_root) {
524 debugfs_remove(priv->debugfs_root);
525 priv->debugfs_root = NULL;
529 static int vga_switcheroo_debugfs_init(struct vgasr_priv *priv)
531 /* already initialised */
532 if (priv->debugfs_root)
533 return 0;
534 priv->debugfs_root = debugfs_create_dir("vgaswitcheroo", NULL);
536 if (!priv->debugfs_root) {
537 printk(KERN_ERR "vga_switcheroo: Cannot create /sys/kernel/debug/vgaswitcheroo\n");
538 goto fail;
541 priv->switch_file = debugfs_create_file("switch", 0644,
542 priv->debugfs_root, NULL, &vga_switcheroo_debugfs_fops);
543 if (!priv->switch_file) {
544 printk(KERN_ERR "vga_switcheroo: cannot create /sys/kernel/debug/vgaswitcheroo/switch\n");
545 goto fail;
547 return 0;
548 fail:
549 vga_switcheroo_debugfs_fini(priv);
550 return -1;
553 int vga_switcheroo_process_delayed_switch(void)
555 struct vga_switcheroo_client *client;
556 int ret;
557 int err = -EINVAL;
559 mutex_lock(&vgasr_mutex);
560 if (!vgasr_priv.delayed_switch_active)
561 goto err;
563 printk(KERN_INFO "vga_switcheroo: processing delayed switch to %d\n", vgasr_priv.delayed_client_id);
565 client = find_client_from_id(&vgasr_priv.clients,
566 vgasr_priv.delayed_client_id);
567 if (!client || !check_can_switch())
568 goto err;
570 ret = vga_switchto_stage2(client);
571 if (ret)
572 printk(KERN_ERR "vga_switcheroo: delayed switching failed stage 2 %d\n", ret);
574 vgasr_priv.delayed_switch_active = false;
575 err = 0;
576 err:
577 mutex_unlock(&vgasr_mutex);
578 return err;
580 EXPORT_SYMBOL(vga_switcheroo_process_delayed_switch);
582 static void vga_switcheroo_power_switch(struct pci_dev *pdev, enum vga_switcheroo_state state)
584 struct vga_switcheroo_client *client;
586 if (!vgasr_priv.handler->power_state)
587 return;
589 client = find_client_from_pci(&vgasr_priv.clients, pdev);
590 if (!client)
591 return;
593 if (!client->driver_power_control)
594 return;
596 vgasr_priv.handler->power_state(client->id, state);
599 /* force a PCI device to a certain state - mainly to turn off audio clients */
601 void vga_switcheroo_set_dynamic_switch(struct pci_dev *pdev, enum vga_switcheroo_state dynamic)
603 struct vga_switcheroo_client *client;
605 client = find_client_from_pci(&vgasr_priv.clients, pdev);
606 if (!client)
607 return;
609 if (!client->driver_power_control)
610 return;
612 client->pwr_state = dynamic;
613 set_audio_state(client->id, dynamic);
615 EXPORT_SYMBOL(vga_switcheroo_set_dynamic_switch);
617 /* switcheroo power domain */
618 static int vga_switcheroo_runtime_suspend(struct device *dev)
620 struct pci_dev *pdev = to_pci_dev(dev);
621 int ret;
623 ret = dev->bus->pm->runtime_suspend(dev);
624 if (ret)
625 return ret;
627 vga_switcheroo_power_switch(pdev, VGA_SWITCHEROO_OFF);
628 return 0;
631 static int vga_switcheroo_runtime_resume(struct device *dev)
633 struct pci_dev *pdev = to_pci_dev(dev);
634 int ret;
636 vga_switcheroo_power_switch(pdev, VGA_SWITCHEROO_ON);
637 ret = dev->bus->pm->runtime_resume(dev);
638 if (ret)
639 return ret;
641 return 0;
644 /* this version is for the case where the power switch is separate
645 to the device being powered down. */
646 int vga_switcheroo_init_domain_pm_ops(struct device *dev, struct dev_pm_domain *domain)
648 /* copy over all the bus versions */
649 if (dev->bus && dev->bus->pm) {
650 domain->ops = *dev->bus->pm;
651 domain->ops.runtime_suspend = vga_switcheroo_runtime_suspend;
652 domain->ops.runtime_resume = vga_switcheroo_runtime_resume;
654 dev->pm_domain = domain;
655 return 0;
657 dev->pm_domain = NULL;
658 return -EINVAL;
660 EXPORT_SYMBOL(vga_switcheroo_init_domain_pm_ops);
662 static int vga_switcheroo_runtime_resume_hdmi_audio(struct device *dev)
664 struct pci_dev *pdev = to_pci_dev(dev);
665 int ret;
666 struct vga_switcheroo_client *client, *found = NULL;
668 /* we need to check if we have to switch back on the video
669 device so the audio device can come back */
670 list_for_each_entry(client, &vgasr_priv.clients, list) {
671 if (PCI_SLOT(client->pdev->devfn) == PCI_SLOT(pdev->devfn) && client_is_vga(client)) {
672 found = client;
673 ret = pm_runtime_get_sync(&client->pdev->dev);
674 if (ret) {
675 if (ret != 1)
676 return ret;
678 break;
681 ret = dev->bus->pm->runtime_resume(dev);
683 /* put the reference for the gpu */
684 if (found) {
685 pm_runtime_mark_last_busy(&found->pdev->dev);
686 pm_runtime_put_autosuspend(&found->pdev->dev);
688 return ret;
691 int vga_switcheroo_init_domain_pm_optimus_hdmi_audio(struct device *dev, struct dev_pm_domain *domain)
693 /* copy over all the bus versions */
694 if (dev->bus && dev->bus->pm) {
695 domain->ops = *dev->bus->pm;
696 domain->ops.runtime_resume = vga_switcheroo_runtime_resume_hdmi_audio;
698 dev->pm_domain = domain;
699 return 0;
701 dev->pm_domain = NULL;
702 return -EINVAL;
704 EXPORT_SYMBOL(vga_switcheroo_init_domain_pm_optimus_hdmi_audio);