![Jiri Slaby](/assets/img/avatar_default.png)
Stanse found that one error path in vga_switcheroo_debugfs_write omits to unlock vgasr_mutex. Fix that. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dave Airlie <airlied@redhat.com>
453 lines
11 KiB
C
453 lines
11 KiB
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);
|
|
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),
|
|
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].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:%c:%s:%s\n", i,
|
|
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)
|
|
{
|
|
int ret;
|
|
|
|
ret = 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);
|
|
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 (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;
|
|
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 (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;
|
|
/* 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);
|
|
|