[deliverable/linux.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>

struct vga_switcheroo_client {
	struct pci_dev *pdev;
	struct fb_info *fb_info;
	int pwr_state;
	void (*set_gpu_state)(struct pci_dev *pdev, enum vga_switcheroo_state);
	void (*reprobe)(struct pci_dev *pdev);
	bool (*can_switch)(struct pci_dev *pdev);
	int id;
	bool active;
};

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 vga_switcheroo_client clients[VGA_SWITCHEROO_MAX_CLIENTS];

	struct vga_switcheroo_handler *handler;
};

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;

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;
	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;
	mutex_unlock(&vgasr_mutex);
}
EXPORT_SYMBOL(vga_switcheroo_unregister_handler);

static void vga_switcheroo_enable(void)
{
	int i;
	int ret;
	/* call the handler to init */
	vgasr_priv.handler->init();

	for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) {
		ret = vgasr_priv.handler->get_client_id(vgasr_priv.clients[i].pdev);
		if (ret < 0)
			return;

		vgasr_priv.clients[i].id = ret;
	}
	vga_switcheroo_debugfs_init(&vgasr_priv);
	vgasr_priv.active = true;
}

int vga_switcheroo_register_client(struct pci_dev *pdev,
				   void (*set_gpu_state)(struct pci_dev *pdev, enum vga_switcheroo_state),
				   void (*reprobe)(struct pci_dev *pdev),
				   bool (*can_switch)(struct pci_dev *pdev))
{
	int index;

	mutex_lock(&vgasr_mutex);
	/* don't do IGD vs DIS here */
	if (vgasr_priv.registered_clients & 1)
		index = 1;
	else
		index = 0;

	vgasr_priv.clients[index].pwr_state = VGA_SWITCHEROO_ON;
	vgasr_priv.clients[index].pdev = pdev;
	vgasr_priv.clients[index].set_gpu_state = set_gpu_state;
	vgasr_priv.clients[index].reprobe = reprobe;
	vgasr_priv.clients[index].can_switch = can_switch;
	vgasr_priv.clients[index].id = -1;
	if (pdev->resource[PCI_ROM_RESOURCE].flags & IORESOURCE_ROM_SHADOW)
		vgasr_priv.clients[index].active = true;

	vgasr_priv.registered_clients |= (1 << index);

	/* if we get two clients + handler */
	if (vgasr_priv.registered_clients == 0x3 && vgasr_priv.handler) {
		printk(KERN_INFO "vga_switcheroo: enabled\n");
		vga_switcheroo_enable();
	}
	mutex_unlock(&vgasr_mutex);
	return 0;
}
EXPORT_SYMBOL(vga_switcheroo_register_client);

void vga_switcheroo_unregister_client(struct pci_dev *pdev)
{
	int i;

	mutex_lock(&vgasr_mutex);
	for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) {
		if (vgasr_priv.clients[i].pdev == pdev) {
			vgasr_priv.registered_clients &= ~(1 << i);
			break;
		}
	}

	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)
{
	int i;

	mutex_lock(&vgasr_mutex);
	for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) {
		if (vgasr_priv.clients[i].pdev == pdev) {
			vgasr_priv.clients[i].fb_info = info;
			break;
		}
	}
	mutex_unlock(&vgasr_mutex);
}
EXPORT_SYMBOL(vga_switcheroo_client_fb_set);

static int vga_switcheroo_show(struct seq_file *m, void *v)
{
	int i;
	mutex_lock(&vgasr_mutex);
	for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) {
		seq_printf(m, "%d:%s:%c:%s:%s\n", i,
			   vgasr_priv.clients[i].id == VGA_SWITCHEROO_DIS ? "DIS" : "IGD",
			   vgasr_priv.clients[i].active ? '+' : ' ',
			   vgasr_priv.clients[i].pwr_state ? "Pwr" : "Off",
			   pci_name(vgasr_priv.clients[i].pdev));
	}
	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->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->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 int vga_switchto(struct vga_switcheroo_client *new_client)
{
	int ret;
	int i;
	struct vga_switcheroo_client *active = NULL;

	if (new_client->active == true)
		return 0;

	for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) {
		if (vgasr_priv.clients[i].active == true) {
			active = &vgasr_priv.clients[i];
			break;
		}
	}
	if (!active)
		return 0;

	/* power up the first device */
	ret = pci_enable_device(new_client->pdev);
	if (ret)
		return ret;

	if (new_client->pwr_state == VGA_SWITCHEROO_OFF)
		vga_switchon(new_client);

	/* swap shadow resource to denote boot VGA device has changed so X starts on new device */
	active->active = false;

	active->pdev->resource[PCI_ROM_RESOURCE].flags &= ~IORESOURCE_ROM_SHADOW;
	new_client->pdev->resource[PCI_ROM_RESOURCE].flags |= IORESOURCE_ROM_SHADOW;

	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->reprobe)
		new_client->reprobe(new_client->pdev);

	if (active->pwr_state == VGA_SWITCHEROO_ON)
		vga_switchoff(active);

	new_client->active = true;
	return 0;
}

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 i, 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) {
		for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) {
			if (vgasr_priv.clients[i].active)
				continue;
			if (vgasr_priv.clients[i].pwr_state == VGA_SWITCHEROO_ON)
				vga_switchoff(&vgasr_priv.clients[i]);
		}
		goto out;
	}
	/* pwr on the device not in use */
	if (strncmp(usercmd, "ON", 2) == 0) {
		for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) {
			if (vgasr_priv.clients[i].active)
				continue;
			if (vgasr_priv.clients[i].pwr_state == VGA_SWITCHEROO_OFF)
				vga_switchon(&vgasr_priv.clients[i]);
		}
		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", 3) == 0) {
		just_mux = true;
		client_id = VGA_SWITCHEROO_IGD;
	}
	if (strncmp(usercmd, "MDIS", 3) == 0) {
		just_mux = true;
		client_id = VGA_SWITCHEROO_DIS;
	}

	if (client_id == -1)
		goto out;

	for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) {
		if (vgasr_priv.clients[i].id == client_id) {
			client = &vgasr_priv.clients[i];
			break;
		}
	}

	vgasr_priv.delayed_switch_active = false;

	if (just_mux) {
		ret = vgasr_priv.handler->switchto(client_id);
		goto out;
	}

	/* okay we want a switch - test if devices are willing to switch */
	can_switch = true;
	for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) {
		can_switch = vgasr_priv.clients[i].can_switch(vgasr_priv.clients[i].pdev);
		if (can_switch == false) {
			printk(KERN_ERR "vga_switcheroo: client %d refused switch\n", i);
			break;
		}
	}

	if (can_switch == false && delay == false)
		goto out;

	if (can_switch == true) {
		pdev_name = pci_name(client->pdev);
		ret = vga_switchto(client);
		if (ret)
			printk(KERN_ERR "vga_switcheroo: switching failed %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;

		/* we should at least power up the card to
		   make the switch faster */
		if (client->pwr_state == VGA_SWITCHEROO_OFF)
			vga_switchon(client);
	}

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 = NULL;
	const char *pdev_name;
	bool can_switch = true;
	int i;
	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);

	for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) {
		if (vgasr_priv.clients[i].id == vgasr_priv.delayed_client_id)
			client = &vgasr_priv.clients[i];
		can_switch = vgasr_priv.clients[i].can_switch(vgasr_priv.clients[i].pdev);
		if (can_switch == false) {
			printk(KERN_ERR "vga_switcheroo: client %d refused switch\n", i);
			break;
		}
	}

	if (can_switch == false || client == NULL)
		goto err;

	pdev_name = pci_name(client->pdev);
	ret = vga_switchto(client);
	if (ret)
		printk(KERN_ERR "vga_switcheroo: delayed switching failed %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
	31	struct vga_switcheroo_client {
	32	struct pci_dev *pdev;
	33	struct fb_info *fb_info;
	34	int pwr_state;
	35	void (set_gpu_state)(struct pci_dev pdev, enum vga_switcheroo_state);
8d608aa6	36	void (reprobe)(struct pci_dev pdev);
6a9ee8af DA	37	bool (can_switch)(struct pci_dev pdev);
	38	int id;
	39	bool active;
	40	};
	41
	42	static DEFINE_MUTEX(vgasr_mutex);
	43
	44	struct vgasr_priv {
	45
	46	bool active;
	47	bool delayed_switch_active;
	48	enum vga_switcheroo_client_id delayed_client_id;
	49
	50	struct dentry *debugfs_root;
	51	struct dentry *switch_file;
	52
	53	int registered_clients;
	54	struct vga_switcheroo_client clients[VGA_SWITCHEROO_MAX_CLIENTS];
	55
	56	struct vga_switcheroo_handler *handler;
	57	};
	58
	59	static int vga_switcheroo_debugfs_init(struct vgasr_priv *priv);
	60	static void vga_switcheroo_debugfs_fini(struct vgasr_priv *priv);
	61
	62	/* only one switcheroo per system */
	63	static struct vgasr_priv vgasr_priv;
	64
	65	int vga_switcheroo_register_handler(struct vga_switcheroo_handler *handler)
	66	{
	67	mutex_lock(&vgasr_mutex);
	68	if (vgasr_priv.handler) {
	69	mutex_unlock(&vgasr_mutex);
	70	return -EINVAL;
	71	}
	72
	73	vgasr_priv.handler = handler;
	74	mutex_unlock(&vgasr_mutex);
	75	return 0;
	76	}
	77	EXPORT_SYMBOL(vga_switcheroo_register_handler);
	78
	79	void vga_switcheroo_unregister_handler(void)
	80	{
	81	mutex_lock(&vgasr_mutex);
	82	vgasr_priv.handler = NULL;
	83	mutex_unlock(&vgasr_mutex);
	84	}
	85	EXPORT_SYMBOL(vga_switcheroo_unregister_handler);
	86
	87	static void vga_switcheroo_enable(void)
	88	{
	89	int i;
	90	int ret;
	91	/* call the handler to init */
	92	vgasr_priv.handler->init();
	93
	94	for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) {
	95	ret = vgasr_priv.handler->get_client_id(vgasr_priv.clients[i].pdev);
	96	if (ret < 0)
	97	return;
	98
	99	vgasr_priv.clients[i].id = ret;
	100	}
101	vga_switcheroo_debugfs_init(&vgasr_priv);
102	vgasr_priv.active = true;
103	}
104
105	int vga_switcheroo_register_client(struct pci_dev *pdev,
106	void (set_gpu_state)(struct pci_dev pdev, enum vga_switcheroo_state),
8d608aa6	107	void (reprobe)(struct pci_dev pdev),
6a9ee8af DA	108	bool (can_switch)(struct pci_dev pdev))
	109	{
	110	int index;
	111
	112	mutex_lock(&vgasr_mutex);
	113	/* don't do IGD vs DIS here */
	114	if (vgasr_priv.registered_clients & 1)
	115	index = 1;
	116	else
	117	index = 0;
	118
	119	vgasr_priv.clients[index].pwr_state = VGA_SWITCHEROO_ON;
	120	vgasr_priv.clients[index].pdev = pdev;
	121	vgasr_priv.clients[index].set_gpu_state = set_gpu_state;
8d608aa6	122	vgasr_priv.clients[index].reprobe = reprobe;
6a9ee8af DA	123	vgasr_priv.clients[index].can_switch = can_switch;
	124	vgasr_priv.clients[index].id = -1;
	125	if (pdev->resource[PCI_ROM_RESOURCE].flags & IORESOURCE_ROM_SHADOW)
	126	vgasr_priv.clients[index].active = true;
	127
	128	vgasr_priv.registered_clients \|= (1 << index);
	129
	130	/* if we get two clients + handler */
	131	if (vgasr_priv.registered_clients == 0x3 && vgasr_priv.handler) {
	132	printk(KERN_INFO "vga_switcheroo: enabled\n");
	133	vga_switcheroo_enable();
	134	}
	135	mutex_unlock(&vgasr_mutex);
	136	return 0;
	137	}
	138	EXPORT_SYMBOL(vga_switcheroo_register_client);
	139
	140	void vga_switcheroo_unregister_client(struct pci_dev *pdev)
	141	{
	142	int i;
	143
	144	mutex_lock(&vgasr_mutex);
	145	for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) {
	146	if (vgasr_priv.clients[i].pdev == pdev) {
	147	vgasr_priv.registered_clients &= ~(1 << i);
	148	break;
	149	}
	150	}
	151
	152	printk(KERN_INFO "vga_switcheroo: disabled\n");
	153	vga_switcheroo_debugfs_fini(&vgasr_priv);
	154	vgasr_priv.active = false;
	155	mutex_unlock(&vgasr_mutex);
	156	}
	157	EXPORT_SYMBOL(vga_switcheroo_unregister_client);
	158
	159	void vga_switcheroo_client_fb_set(struct pci_dev *pdev,
	160	struct fb_info *info)
	161	{
	162	int i;
	163
	164	mutex_lock(&vgasr_mutex);
	165	for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) {
	166	if (vgasr_priv.clients[i].pdev == pdev) {
	167	vgasr_priv.clients[i].fb_info = info;
	168	break;
	169	}
	170	}
	171	mutex_unlock(&vgasr_mutex);
	172	}
	173	EXPORT_SYMBOL(vga_switcheroo_client_fb_set);
	174
	175	static int vga_switcheroo_show(struct seq_file m, void v)
	176	{
	177	int i;
	178	mutex_lock(&vgasr_mutex);
	179	for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) {
6c2df40e DA	180	seq_printf(m, "%d:%s:%c:%s:%s\n", i,
6c2df40e DA	181	vgasr_priv.clients[i].id == VGA_SWITCHEROO_DIS ? "DIS" : "IGD",
6a9ee8af DA	182	vgasr_priv.clients[i].active ? '+' : ' ',
	183	vgasr_priv.clients[i].pwr_state ? "Pwr" : "Off",
	184	pci_name(vgasr_priv.clients[i].pdev));
	185	}
	186	mutex_unlock(&vgasr_mutex);
	187	return 0;
	188	}
	189
	190	static int vga_switcheroo_debugfs_open(struct inode inode, struct file file)
	191	{
	192	return single_open(file, vga_switcheroo_show, NULL);
	193	}
	194
	195	static int vga_switchon(struct vga_switcheroo_client *client)
	196	{
5cfb3c3a DA	197	if (vgasr_priv.handler->power_state)
5cfb3c3a DA	198	vgasr_priv.handler->power_state(client->id, VGA_SWITCHEROO_ON);
6a9ee8af DA	199	/* call the driver callback to turn on device */
	200	client->set_gpu_state(client->pdev, VGA_SWITCHEROO_ON);
	201	client->pwr_state = VGA_SWITCHEROO_ON;
	202	return 0;
	203	}
	204
	205	static int vga_switchoff(struct vga_switcheroo_client *client)
	206	{
	207	/* call the driver callback to turn off device */
	208	client->set_gpu_state(client->pdev, VGA_SWITCHEROO_OFF);
5cfb3c3a DA	209	if (vgasr_priv.handler->power_state)
5cfb3c3a DA	210	vgasr_priv.handler->power_state(client->id, VGA_SWITCHEROO_OFF);
6a9ee8af DA	211	client->pwr_state = VGA_SWITCHEROO_OFF;
	212	return 0;
	213	}
	214
	215	static int vga_switchto(struct vga_switcheroo_client *new_client)
	216	{
	217	int ret;
	218	int i;
	219	struct vga_switcheroo_client *active = NULL;
	220
	221	if (new_client->active == true)
	222	return 0;
	223
	224	for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) {
	225	if (vgasr_priv.clients[i].active == true) {
	226	active = &vgasr_priv.clients[i];
	227	break;
	228	}
	229	}
	230	if (!active)
	231	return 0;
	232
	233	/* power up the first device */
	234	ret = pci_enable_device(new_client->pdev);
	235	if (ret)
	236	return ret;
	237
	238	if (new_client->pwr_state == VGA_SWITCHEROO_OFF)
	239	vga_switchon(new_client);
	240
	241	/* swap shadow resource to denote boot VGA device has changed so X starts on new device */
	242	active->active = false;
	243
	244	active->pdev->resource[PCI_ROM_RESOURCE].flags &= ~IORESOURCE_ROM_SHADOW;
	245	new_client->pdev->resource[PCI_ROM_RESOURCE].flags \|= IORESOURCE_ROM_SHADOW;
	246
	247	if (new_client->fb_info) {
	248	struct fb_event event;
	249	event.info = new_client->fb_info;
	250	fb_notifier_call_chain(FB_EVENT_REMAP_ALL_CONSOLE, &event);
	251	}
	252
	253	ret = vgasr_priv.handler->switchto(new_client->id);
	254	if (ret)
	255	return ret;
	256
8d608aa6 DA	257	if (new_client->reprobe)
	258	new_client->reprobe(new_client->pdev);
	259
6a9ee8af DA	260	if (active->pwr_state == VGA_SWITCHEROO_ON)
	261	vga_switchoff(active);
	262
	263	new_client->active = true;
	264	return 0;
	265	}
	266
	267	static ssize_t
	268	vga_switcheroo_debugfs_write(struct file filp, const char __user ubuf,
	269	size_t cnt, loff_t *ppos)
	270	{
	271	char usercmd[64];
	272	const char *pdev_name;
	273	int i, ret;
	274	bool delay = false, can_switch;
851ab954	275	bool just_mux = false;
6a9ee8af DA	276	int client_id = -1;
	277	struct vga_switcheroo_client *client = NULL;
	278
	279	if (cnt > 63)
	280	cnt = 63;
	281
	282	if (copy_from_user(usercmd, ubuf, cnt))
	283	return -EFAULT;
	284
	285	mutex_lock(&vgasr_mutex);
	286
8c88e50b JS	287	if (!vgasr_priv.active) {
	288	cnt = -EINVAL;
	289	goto out;
	290	}
6a9ee8af DA	291
	292	/* pwr off the device not in use */
	293	if (strncmp(usercmd, "OFF", 3) == 0) {
	294	for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) {
	295	if (vgasr_priv.clients[i].active)
	296	continue;
	297	if (vgasr_priv.clients[i].pwr_state == VGA_SWITCHEROO_ON)
	298	vga_switchoff(&vgasr_priv.clients[i]);
	299	}
	300	goto out;
	301	}
	302	/* pwr on the device not in use */
	303	if (strncmp(usercmd, "ON", 2) == 0) {
	304	for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) {
	305	if (vgasr_priv.clients[i].active)
	306	continue;
	307	if (vgasr_priv.clients[i].pwr_state == VGA_SWITCHEROO_OFF)
	308	vga_switchon(&vgasr_priv.clients[i]);
	309	}
	310	goto out;
	311	}
	312
	313	/* request a delayed switch - test can we switch now */
	314	if (strncmp(usercmd, "DIGD", 4) == 0) {
	315	client_id = VGA_SWITCHEROO_IGD;
	316	delay = true;
	317	}
	318
	319	if (strncmp(usercmd, "DDIS", 4) == 0) {
	320	client_id = VGA_SWITCHEROO_DIS;
	321	delay = true;
	322	}
	323
	324	if (strncmp(usercmd, "IGD", 3) == 0)
	325	client_id = VGA_SWITCHEROO_IGD;
	326
	327	if (strncmp(usercmd, "DIS", 3) == 0)
	328	client_id = VGA_SWITCHEROO_DIS;
	329
851ab954 DA	330	if (strncmp(usercmd, "MIGD", 3) == 0) {
	331	just_mux = true;
	332	client_id = VGA_SWITCHEROO_IGD;
	333	}
	334	if (strncmp(usercmd, "MDIS", 3) == 0) {
	335	just_mux = true;
	336	client_id = VGA_SWITCHEROO_DIS;
	337	}
	338
6a9ee8af DA	339	if (client_id == -1)
	340	goto out;
	341
	342	for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) {
	343	if (vgasr_priv.clients[i].id == client_id) {
	344	client = &vgasr_priv.clients[i];
	345	break;
	346	}
	347	}
	348
	349	vgasr_priv.delayed_switch_active = false;
851ab954 DA	350
	351	if (just_mux) {
	352	ret = vgasr_priv.handler->switchto(client_id);
	353	goto out;
	354	}
	355
6a9ee8af DA	356	/* okay we want a switch - test if devices are willing to switch */
	357	can_switch = true;
	358	for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) {
	359	can_switch = vgasr_priv.clients[i].can_switch(vgasr_priv.clients[i].pdev);
	360	if (can_switch == false) {
	361	printk(KERN_ERR "vga_switcheroo: client %d refused switch\n", i);
	362	break;
	363	}
	364	}
	365
	366	if (can_switch == false && delay == false)
	367	goto out;
	368
	369	if (can_switch == true) {
	370	pdev_name = pci_name(client->pdev);
	371	ret = vga_switchto(client);
	372	if (ret)
	373	printk(KERN_ERR "vga_switcheroo: switching failed %d\n", ret);
	374	} else {
	375	printk(KERN_INFO "vga_switcheroo: setting delayed switch to client %d\n", client->id);
	376	vgasr_priv.delayed_switch_active = true;
	377	vgasr_priv.delayed_client_id = client_id;
	378
	379	/* we should at least power up the card to
	380	make the switch faster */
	381	if (client->pwr_state == VGA_SWITCHEROO_OFF)
	382	vga_switchon(client);
	383	}
	384
	385	out:
	386	mutex_unlock(&vgasr_mutex);
	387	return cnt;
	388	}
	389
	390	static const struct file_operations vga_switcheroo_debugfs_fops = {
	391	.owner = THIS_MODULE,
	392	.open = vga_switcheroo_debugfs_open,
	393	.write = vga_switcheroo_debugfs_write,
	394	.read = seq_read,
	395	.llseek = seq_lseek,
	396	.release = single_release,
	397	};
	398
	399	static void vga_switcheroo_debugfs_fini(struct vgasr_priv *priv)
	400	{
	401	if (priv->switch_file) {
	402	debugfs_remove(priv->switch_file);
	403	priv->switch_file = NULL;
	404	}
	405	if (priv->debugfs_root) {
	406	debugfs_remove(priv->debugfs_root);
	407	priv->debugfs_root = NULL;
	408	}
	409	}
	410
	411	static int vga_switcheroo_debugfs_init(struct vgasr_priv *priv)
	412	{
	413	/* already initialised */
	414	if (priv->debugfs_root)
	415	return 0;
	416	priv->debugfs_root = debugfs_create_dir("vgaswitcheroo", NULL);
	417
	418	if (!priv->debugfs_root) {
	419	printk(KERN_ERR "vga_switcheroo: Cannot create /sys/kernel/debug/vgaswitcheroo\n");
420	goto fail;
421	}
422
423	priv->switch_file = debugfs_create_file("switch", 0644,
424	priv->debugfs_root, NULL, &vga_switcheroo_debugfs_fops);
425	if (!priv->switch_file) {
426	printk(KERN_ERR "vga_switcheroo: cannot create /sys/kernel/debug/vgaswitcheroo/switch\n");
427	goto fail;
428	}
429	return 0;
430	fail:
431	vga_switcheroo_debugfs_fini(priv);
432	return -1;
433	}
434
435	int vga_switcheroo_process_delayed_switch(void)
436	{
437	struct vga_switcheroo_client *client = NULL;
438	const char *pdev_name;
439	bool can_switch = true;
440	int i;
441	int ret;
442	int err = -EINVAL;
443
444	mutex_lock(&vgasr_mutex);
445	if (!vgasr_priv.delayed_switch_active)
446	goto err;
447
448	printk(KERN_INFO "vga_switcheroo: processing delayed switch to %d\n", vgasr_priv.delayed_client_id);
449
450	for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) {
451	if (vgasr_priv.clients[i].id == vgasr_priv.delayed_client_id)
452	client = &vgasr_priv.clients[i];
453	can_switch = vgasr_priv.clients[i].can_switch(vgasr_priv.clients[i].pdev);
454	if (can_switch == false) {
455	printk(KERN_ERR "vga_switcheroo: client %d refused switch\n", i);
456	break;
457	}
458	}
459
460	if (can_switch == false \|\| client == NULL)
461	goto err;
462
463	pdev_name = pci_name(client->pdev);
464	ret = vga_switchto(client);
465	if (ret)
466	printk(KERN_ERR "vga_switcheroo: delayed switching failed %d\n", ret);
467
468	vgasr_priv.delayed_switch_active = false;
469	err = 0;
470	err:
471	mutex_unlock(&vgasr_mutex);
472	return err;
473	}
474	EXPORT_SYMBOL(vga_switcheroo_process_delayed_switch);
475