[mirror_ubuntu-zesty-kernel.git] / drivers / gpu / vga / vga_switcheroo.c

/*
 * 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/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;
		event.info = new_client->fb_info;
		fb_notifier_call_chain(FB_EVENT_REMAP_ALL_CONSOLE, &event);
	}

	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);
Commit	Line	Data
6a9ee8af DA	1	/*
	2	* Copyright (c) 2010 Red Hat Inc.
	3	* Author : Dave Airlie <airlied@redhat.com>
	4	*
	5	*
	6	* Licensed under GPLv2
	7	*
	8	* vga_switcheroo.c - Support for laptop with dual GPU using one set of outputs
	9
	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
	13
	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
	18	*/
	19
	20	#include <linux/module.h>
	21	#include <linux/dmi.h>
	22	#include <linux/seq_file.h>
	23	#include <linux/uaccess.h>
	24	#include <linux/fs.h>
	25	#include <linux/debugfs.h>
	26	#include <linux/fb.h>
	27
6a9ee8af DA	28	#include <linux/pci.h>
	29	#include <linux/vga_switcheroo.h>
	30
2fbe8c7c MG	31	#include <linux/vgaarb.h>
2fbe8c7c MG	32
6a9ee8af DA	33	struct vga_switcheroo_client {
	34	struct pci_dev *pdev;
	35	struct fb_info *fb_info;
	36	int pwr_state;
26ec685f	37	const struct vga_switcheroo_client_ops *ops;
6a9ee8af DA	38	int id;
6a9ee8af DA	39	bool active;
79721e0a	40	struct list_head list;
6a9ee8af DA	41	};
	42
	43	static DEFINE_MUTEX(vgasr_mutex);
	44
	45	struct vgasr_priv {
	46
	47	bool active;
	48	bool delayed_switch_active;
	49	enum vga_switcheroo_client_id delayed_client_id;
	50
	51	struct dentry *debugfs_root;
	52	struct dentry *switch_file;
	53
	54	int registered_clients;
79721e0a	55	struct list_head clients;
6a9ee8af DA	56
	57	struct vga_switcheroo_handler *handler;
	58	};
	59
3e9e63db TI	60	#define ID_BIT_AUDIO 0x100
	61	#define client_is_audio(c) ((c)->id & ID_BIT_AUDIO)
	62	#define client_is_vga(c) ((c)->id == -1 \|\| !client_is_audio(c))
	63	#define client_id(c) ((c)->id & ~ID_BIT_AUDIO)
	64
6a9ee8af DA	65	static int vga_switcheroo_debugfs_init(struct vgasr_priv *priv);
	66	static void vga_switcheroo_debugfs_fini(struct vgasr_priv *priv);
	67
	68	/* only one switcheroo per system */
79721e0a TI	69	static struct vgasr_priv vgasr_priv = {
	70	.clients = LIST_HEAD_INIT(vgasr_priv.clients),
	71	};
6a9ee8af	72
36704c0c	73	static bool vga_switcheroo_ready(void)
6a9ee8af	74	{
36704c0c SF	75	/* we're ready if we get two clients + handler */
	76	return !vgasr_priv.active &&
	77	vgasr_priv.registered_clients == 2 && vgasr_priv.handler;
6a9ee8af	78	}
6a9ee8af DA	79
	80	static void vga_switcheroo_enable(void)
	81	{
6a9ee8af	82	int ret;
79721e0a TI	83	struct vga_switcheroo_client *client;
79721e0a TI	84
6a9ee8af	85	/* call the handler to init */
e99eac5e SF	86	if (vgasr_priv.handler->init)
e99eac5e SF	87	vgasr_priv.handler->init();
6a9ee8af	88
79721e0a	89	list_for_each_entry(client, &vgasr_priv.clients, list) {
3e9e63db TI	90	if (client->id != -1)
3e9e63db TI	91	continue;
79721e0a	92	ret = vgasr_priv.handler->get_client_id(client->pdev);
6a9ee8af DA	93	if (ret < 0)
	94	return;
	95
79721e0a	96	client->id = ret;
6a9ee8af DA	97	}
	98	vga_switcheroo_debugfs_init(&vgasr_priv);
	99	vgasr_priv.active = true;
	100	}
	101
36704c0c SF	102	int vga_switcheroo_register_handler(struct vga_switcheroo_handler *handler)
	103	{
	104	mutex_lock(&vgasr_mutex);
	105	if (vgasr_priv.handler) {
	106	mutex_unlock(&vgasr_mutex);
	107	return -EINVAL;
	108	}
	109
	110	vgasr_priv.handler = handler;
	111	if (vga_switcheroo_ready()) {
	112	printk(KERN_INFO "vga_switcheroo: enabled\n");
	113	vga_switcheroo_enable();
	114	}
	115	mutex_unlock(&vgasr_mutex);
	116	return 0;
	117	}
	118	EXPORT_SYMBOL(vga_switcheroo_register_handler);
	119
	120	void vga_switcheroo_unregister_handler(void)
	121	{
	122	mutex_lock(&vgasr_mutex);
	123	vgasr_priv.handler = NULL;
	124	if (vgasr_priv.active) {
	125	pr_info("vga_switcheroo: disabled\n");
	126	vga_switcheroo_debugfs_fini(&vgasr_priv);
	127	vgasr_priv.active = false;
	128	}
	129	mutex_unlock(&vgasr_mutex);
	130	}
	131	EXPORT_SYMBOL(vga_switcheroo_unregister_handler);
	132
3e9e63db TI	133	static int register_client(struct pci_dev *pdev,
	134	const struct vga_switcheroo_client_ops *ops,
	135	int id, bool active)
6a9ee8af	136	{
79721e0a	137	struct vga_switcheroo_client *client;
6a9ee8af	138
79721e0a TI	139	client = kzalloc(sizeof(*client), GFP_KERNEL);
	140	if (!client)
	141	return -ENOMEM;
	142
	143	client->pwr_state = VGA_SWITCHEROO_ON;
	144	client->pdev = pdev;
26ec685f	145	client->ops = ops;
3e9e63db TI	146	client->id = id;
3e9e63db TI	147	client->active = active;
6a9ee8af	148
79721e0a TI	149	mutex_lock(&vgasr_mutex);
79721e0a TI	150	list_add_tail(&client->list, &vgasr_priv.clients);
3e9e63db TI	151	if (client_is_vga(client))
3e9e63db TI	152	vgasr_priv.registered_clients++;
6a9ee8af	153
36704c0c	154	if (vga_switcheroo_ready()) {
6a9ee8af DA	155	printk(KERN_INFO "vga_switcheroo: enabled\n");
	156	vga_switcheroo_enable();
	157	}
	158	mutex_unlock(&vgasr_mutex);
	159	return 0;
	160	}
3e9e63db TI	161
	162	int vga_switcheroo_register_client(struct pci_dev *pdev,
	163	const struct vga_switcheroo_client_ops *ops)
	164	{
	165	return register_client(pdev, ops, -1,
	166	pdev == vga_default_device());
	167	}
6a9ee8af DA	168	EXPORT_SYMBOL(vga_switcheroo_register_client);
6a9ee8af DA	169
3e9e63db TI	170	int vga_switcheroo_register_audio_client(struct pci_dev *pdev,
	171	const struct vga_switcheroo_client_ops *ops,
	172	int id, bool active)
	173	{
	174	return register_client(pdev, ops, id \| ID_BIT_AUDIO, active);
	175	}
	176	EXPORT_SYMBOL(vga_switcheroo_register_audio_client);
	177
79721e0a TI	178	static struct vga_switcheroo_client *
	179	find_client_from_pci(struct list_head head, struct pci_dev pdev)
	180	{
	181	struct vga_switcheroo_client *client;
	182	list_for_each_entry(client, head, list)
	183	if (client->pdev == pdev)
	184	return client;
	185	return NULL;
	186	}
	187
	188	static struct vga_switcheroo_client *
	189	find_client_from_id(struct list_head *head, int client_id)
	190	{
	191	struct vga_switcheroo_client *client;
	192	list_for_each_entry(client, head, list)
	193	if (client->id == client_id)
	194	return client;
	195	return NULL;
	196	}
	197
	198	static struct vga_switcheroo_client *
	199	find_active_client(struct list_head *head)
	200	{
	201	struct vga_switcheroo_client *client;
	202	list_for_each_entry(client, head, list)
3e9e63db	203	if (client->active && client_is_vga(client))
79721e0a TI	204	return client;
	205	return NULL;
	206	}
	207
c8e9cf7b TI	208	int vga_switcheroo_get_client_state(struct pci_dev *pdev)
	209	{
	210	struct vga_switcheroo_client *client;
	211
	212	client = find_client_from_pci(&vgasr_priv.clients, pdev);
	213	if (!client)
	214	return VGA_SWITCHEROO_NOT_FOUND;
	215	if (!vgasr_priv.active)
	216	return VGA_SWITCHEROO_INIT;
	217	return client->pwr_state;
	218	}
	219	EXPORT_SYMBOL(vga_switcheroo_get_client_state);
	220
6a9ee8af DA	221	void vga_switcheroo_unregister_client(struct pci_dev *pdev)
6a9ee8af DA	222	{
79721e0a	223	struct vga_switcheroo_client *client;
6a9ee8af DA	224
6a9ee8af DA	225	mutex_lock(&vgasr_mutex);
79721e0a TI	226	client = find_client_from_pci(&vgasr_priv.clients, pdev);
79721e0a TI	227	if (client) {
3e9e63db TI	228	if (client_is_vga(client))
3e9e63db TI	229	vgasr_priv.registered_clients--;
79721e0a TI	230	list_del(&client->list);
79721e0a TI	231	kfree(client);
6a9ee8af	232	}
3e9e63db TI	233	if (vgasr_priv.active && vgasr_priv.registered_clients < 2) {
	234	printk(KERN_INFO "vga_switcheroo: disabled\n");
	235	vga_switcheroo_debugfs_fini(&vgasr_priv);
	236	vgasr_priv.active = false;
	237	}
6a9ee8af DA	238	mutex_unlock(&vgasr_mutex);
	239	}
	240	EXPORT_SYMBOL(vga_switcheroo_unregister_client);
	241
	242	void vga_switcheroo_client_fb_set(struct pci_dev *pdev,
	243	struct fb_info *info)
	244	{
79721e0a	245	struct vga_switcheroo_client *client;
6a9ee8af DA	246
6a9ee8af DA	247	mutex_lock(&vgasr_mutex);
79721e0a TI	248	client = find_client_from_pci(&vgasr_priv.clients, pdev);
	249	if (client)
	250	client->fb_info = info;
6a9ee8af DA	251	mutex_unlock(&vgasr_mutex);
	252	}
	253	EXPORT_SYMBOL(vga_switcheroo_client_fb_set);
	254
	255	static int vga_switcheroo_show(struct seq_file m, void v)
	256	{
79721e0a TI	257	struct vga_switcheroo_client *client;
79721e0a TI	258	int i = 0;
6a9ee8af	259	mutex_lock(&vgasr_mutex);
79721e0a	260	list_for_each_entry(client, &vgasr_priv.clients, list) {
3e9e63db TI	261	seq_printf(m, "%d:%s%s:%c:%s:%s\n", i,
	262	client_id(client) == VGA_SWITCHEROO_DIS ? "DIS" : "IGD",
	263	client_is_vga(client) ? "" : "-Audio",
79721e0a TI	264	client->active ? '+' : ' ',
	265	client->pwr_state ? "Pwr" : "Off",
	266	pci_name(client->pdev));
	267	i++;
6a9ee8af DA	268	}
	269	mutex_unlock(&vgasr_mutex);
	270	return 0;
	271	}
	272
	273	static int vga_switcheroo_debugfs_open(struct inode inode, struct file file)
	274	{
	275	return single_open(file, vga_switcheroo_show, NULL);
	276	}
	277
	278	static int vga_switchon(struct vga_switcheroo_client *client)
	279	{
5cfb3c3a DA	280	if (vgasr_priv.handler->power_state)
5cfb3c3a DA	281	vgasr_priv.handler->power_state(client->id, VGA_SWITCHEROO_ON);
6a9ee8af	282	/* call the driver callback to turn on device */
26ec685f	283	client->ops->set_gpu_state(client->pdev, VGA_SWITCHEROO_ON);
6a9ee8af DA	284	client->pwr_state = VGA_SWITCHEROO_ON;
	285	return 0;
	286	}
	287
	288	static int vga_switchoff(struct vga_switcheroo_client *client)
	289	{
	290	/* call the driver callback to turn off device */
26ec685f	291	client->ops->set_gpu_state(client->pdev, VGA_SWITCHEROO_OFF);
5cfb3c3a DA	292	if (vgasr_priv.handler->power_state)
5cfb3c3a DA	293	vgasr_priv.handler->power_state(client->id, VGA_SWITCHEROO_OFF);
6a9ee8af DA	294	client->pwr_state = VGA_SWITCHEROO_OFF;
	295	return 0;
	296	}
	297
3e9e63db TI	298	static void set_audio_state(int id, int state)
	299	{
	300	struct vga_switcheroo_client *client;
	301
	302	client = find_client_from_id(&vgasr_priv.clients, id \| ID_BIT_AUDIO);
	303	if (client && client->pwr_state != state) {
	304	client->ops->set_gpu_state(client->pdev, state);
	305	client->pwr_state = state;
	306	}
	307	}
	308
66b37c67 DA	309	/* stage one happens before delay */
66b37c67 DA	310	static int vga_switchto_stage1(struct vga_switcheroo_client *new_client)
6a9ee8af	311	{
79721e0a	312	struct vga_switcheroo_client *active;
6a9ee8af	313
79721e0a	314	active = find_active_client(&vgasr_priv.clients);
6a9ee8af DA	315	if (!active)
	316	return 0;
	317
6a9ee8af DA	318	if (new_client->pwr_state == VGA_SWITCHEROO_OFF)
	319	vga_switchon(new_client);
	320
2fbe8c7c	321	vga_set_default_device(new_client->pdev);
66b37c67 DA	322	return 0;
	323	}
	324
	325	/* post delay */
	326	static int vga_switchto_stage2(struct vga_switcheroo_client *new_client)
	327	{
	328	int ret;
79721e0a	329	struct vga_switcheroo_client *active;
66b37c67	330
79721e0a	331	active = find_active_client(&vgasr_priv.clients);
66b37c67 DA	332	if (!active)
	333	return 0;
	334
	335	active->active = false;
6a9ee8af	336
c91c3fae TI	337	set_audio_state(active->id, VGA_SWITCHEROO_OFF);
c91c3fae TI	338
6a9ee8af DA	339	if (new_client->fb_info) {
	340	struct fb_event event;
	341	event.info = new_client->fb_info;
	342	fb_notifier_call_chain(FB_EVENT_REMAP_ALL_CONSOLE, &event);
	343	}
	344
	345	ret = vgasr_priv.handler->switchto(new_client->id);
	346	if (ret)
	347	return ret;
	348
26ec685f TI	349	if (new_client->ops->reprobe)
26ec685f TI	350	new_client->ops->reprobe(new_client->pdev);
8d608aa6	351
6a9ee8af DA	352	if (active->pwr_state == VGA_SWITCHEROO_ON)
	353	vga_switchoff(active);
	354
c91c3fae TI	355	set_audio_state(new_client->id, VGA_SWITCHEROO_ON);
c91c3fae TI	356
6a9ee8af DA	357	new_client->active = true;
	358	return 0;
	359	}
	360
79721e0a TI	361	static bool check_can_switch(void)
	362	{
	363	struct vga_switcheroo_client *client;
	364
	365	list_for_each_entry(client, &vgasr_priv.clients, list) {
26ec685f	366	if (!client->ops->can_switch(client->pdev)) {
79721e0a TI	367	printk(KERN_ERR "vga_switcheroo: client %x refused switch\n", client->id);
	368	return false;
	369	}
	370	}
	371	return true;
	372	}
	373
6a9ee8af DA	374	static ssize_t
	375	vga_switcheroo_debugfs_write(struct file filp, const char __user ubuf,
	376	size_t cnt, loff_t *ppos)
	377	{
	378	char usercmd[64];
	379	const char *pdev_name;
79721e0a	380	int ret;
6a9ee8af	381	bool delay = false, can_switch;
851ab954	382	bool just_mux = false;
6a9ee8af DA	383	int client_id = -1;
	384	struct vga_switcheroo_client *client = NULL;
	385
	386	if (cnt > 63)
	387	cnt = 63;
	388
	389	if (copy_from_user(usercmd, ubuf, cnt))
	390	return -EFAULT;
	391
	392	mutex_lock(&vgasr_mutex);
	393
8c88e50b JS	394	if (!vgasr_priv.active) {
	395	cnt = -EINVAL;
	396	goto out;
	397	}
6a9ee8af DA	398
	399	/* pwr off the device not in use */
	400	if (strncmp(usercmd, "OFF", 3) == 0) {
79721e0a	401	list_for_each_entry(client, &vgasr_priv.clients, list) {
c91c3fae	402	if (client->active \|\| client_is_audio(client))
6a9ee8af	403	continue;
c91c3fae	404	set_audio_state(client->id, VGA_SWITCHEROO_OFF);
79721e0a TI	405	if (client->pwr_state == VGA_SWITCHEROO_ON)
79721e0a TI	406	vga_switchoff(client);
6a9ee8af DA	407	}
	408	goto out;
	409	}
	410	/* pwr on the device not in use */
	411	if (strncmp(usercmd, "ON", 2) == 0) {
79721e0a	412	list_for_each_entry(client, &vgasr_priv.clients, list) {
c91c3fae	413	if (client->active \|\| client_is_audio(client))
6a9ee8af	414	continue;
79721e0a TI	415	if (client->pwr_state == VGA_SWITCHEROO_OFF)
79721e0a TI	416	vga_switchon(client);
c91c3fae	417	set_audio_state(client->id, VGA_SWITCHEROO_ON);
6a9ee8af DA	418	}
	419	goto out;
	420	}
	421
	422	/* request a delayed switch - test can we switch now */
	423	if (strncmp(usercmd, "DIGD", 4) == 0) {
	424	client_id = VGA_SWITCHEROO_IGD;
	425	delay = true;
	426	}
	427
	428	if (strncmp(usercmd, "DDIS", 4) == 0) {
	429	client_id = VGA_SWITCHEROO_DIS;
	430	delay = true;
	431	}
	432
	433	if (strncmp(usercmd, "IGD", 3) == 0)
	434	client_id = VGA_SWITCHEROO_IGD;
	435
	436	if (strncmp(usercmd, "DIS", 3) == 0)
	437	client_id = VGA_SWITCHEROO_DIS;
	438
fea6f330	439	if (strncmp(usercmd, "MIGD", 4) == 0) {
851ab954 DA	440	just_mux = true;
	441	client_id = VGA_SWITCHEROO_IGD;
	442	}
fea6f330	443	if (strncmp(usercmd, "MDIS", 4) == 0) {
851ab954 DA	444	just_mux = true;
	445	client_id = VGA_SWITCHEROO_DIS;
	446	}
	447
6a9ee8af DA	448	if (client_id == -1)
6a9ee8af DA	449	goto out;
79721e0a TI	450	client = find_client_from_id(&vgasr_priv.clients, client_id);
	451	if (!client)
	452	goto out;
6a9ee8af DA	453
6a9ee8af DA	454	vgasr_priv.delayed_switch_active = false;
851ab954 DA	455
	456	if (just_mux) {
	457	ret = vgasr_priv.handler->switchto(client_id);
	458	goto out;
	459	}
	460
79721e0a	461	if (client->active)
a67b8887 FM	462	goto out;
a67b8887 FM	463
6a9ee8af	464	/* okay we want a switch - test if devices are willing to switch */
79721e0a	465	can_switch = check_can_switch();
6a9ee8af DA	466
	467	if (can_switch == false && delay == false)
	468	goto out;
	469
79721e0a	470	if (can_switch) {
6a9ee8af	471	pdev_name = pci_name(client->pdev);
66b37c67 DA	472	ret = vga_switchto_stage1(client);
	473	if (ret)
	474	printk(KERN_ERR "vga_switcheroo: switching failed stage 1 %d\n", ret);
	475
	476	ret = vga_switchto_stage2(client);
6a9ee8af	477	if (ret)
66b37c67 DA	478	printk(KERN_ERR "vga_switcheroo: switching failed stage 2 %d\n", ret);
66b37c67 DA	479
6a9ee8af DA	480	} else {
	481	printk(KERN_INFO "vga_switcheroo: setting delayed switch to client %d\n", client->id);
	482	vgasr_priv.delayed_switch_active = true;
	483	vgasr_priv.delayed_client_id = client_id;
	484
66b37c67 DA	485	ret = vga_switchto_stage1(client);
	486	if (ret)
	487	printk(KERN_ERR "vga_switcheroo: delayed switching stage 1 failed %d\n", ret);
6a9ee8af DA	488	}
	489
	490	out:
	491	mutex_unlock(&vgasr_mutex);
	492	return cnt;
	493	}
	494
	495	static const struct file_operations vga_switcheroo_debugfs_fops = {
	496	.owner = THIS_MODULE,
	497	.open = vga_switcheroo_debugfs_open,
	498	.write = vga_switcheroo_debugfs_write,
	499	.read = seq_read,
	500	.llseek = seq_lseek,
	501	.release = single_release,
	502	};
	503
	504	static void vga_switcheroo_debugfs_fini(struct vgasr_priv *priv)
	505	{
	506	if (priv->switch_file) {
	507	debugfs_remove(priv->switch_file);
	508	priv->switch_file = NULL;
	509	}
	510	if (priv->debugfs_root) {
	511	debugfs_remove(priv->debugfs_root);
	512	priv->debugfs_root = NULL;
	513	}
	514	}
	515
	516	static int vga_switcheroo_debugfs_init(struct vgasr_priv *priv)
	517	{
	518	/* already initialised */
	519	if (priv->debugfs_root)
	520	return 0;
	521	priv->debugfs_root = debugfs_create_dir("vgaswitcheroo", NULL);
	522
	523	if (!priv->debugfs_root) {
	524	printk(KERN_ERR "vga_switcheroo: Cannot create /sys/kernel/debug/vgaswitcheroo\n");
	525	goto fail;
	526	}
	527
	528	priv->switch_file = debugfs_create_file("switch", 0644,
	529	priv->debugfs_root, NULL, &vga_switcheroo_debugfs_fops);
	530	if (!priv->switch_file) {
	531	printk(KERN_ERR "vga_switcheroo: cannot create /sys/kernel/debug/vgaswitcheroo/switch\n");
	532	goto fail;
	533	}
	534	return 0;
	535	fail:
	536	vga_switcheroo_debugfs_fini(priv);
	537	return -1;
	538	}
	539
	540	int vga_switcheroo_process_delayed_switch(void)
	541	{
79721e0a	542	struct vga_switcheroo_client *client;
6a9ee8af	543	const char *pdev_name;
6a9ee8af DA	544	int ret;
	545	int err = -EINVAL;
	546
	547	mutex_lock(&vgasr_mutex);
	548	if (!vgasr_priv.delayed_switch_active)
	549	goto err;
	550
	551	printk(KERN_INFO "vga_switcheroo: processing delayed switch to %d\n", vgasr_priv.delayed_client_id);
	552
79721e0a TI	553	client = find_client_from_id(&vgasr_priv.clients,
	554	vgasr_priv.delayed_client_id);
	555	if (!client \|\| !check_can_switch())
6a9ee8af DA	556	goto err;
	557
	558	pdev_name = pci_name(client->pdev);
66b37c67	559	ret = vga_switchto_stage2(client);
6a9ee8af	560	if (ret)
66b37c67	561	printk(KERN_ERR "vga_switcheroo: delayed switching failed stage 2 %d\n", ret);
6a9ee8af DA	562
	563	vgasr_priv.delayed_switch_active = false;
	564	err = 0;
	565	err:
	566	mutex_unlock(&vgasr_mutex);
	567	return err;
	568	}
	569	EXPORT_SYMBOL(vga_switcheroo_process_delayed_switch);
	570