Skip to content

Commit

Permalink
vga_switcheroo: Refactor using linked list
Browse files Browse the repository at this point in the history 
Refactor the code base a bit for the further work to adapt more clients.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
  • Loading branch information
Takashi Iwai committed May 13, 2012
1 parent 218c872 commit 79721e0
Showing 1 changed file with 110 additions and 99 deletions.
209 changes: 110 additions & 99 deletions drivers/gpu/vga/vga_switcheroo.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -39,6 +39,7 @@ struct vga_switcheroo_client {
bool (*can_switch)(struct pci_dev *pdev);
int id;
bool active;
struct list_head list;
};

static DEFINE_MUTEX(vgasr_mutex);
Expand All @@ -53,7 +54,7 @@ struct vgasr_priv {
struct dentry *switch_file;

int registered_clients;
struct vga_switcheroo_client clients[VGA_SWITCHEROO_MAX_CLIENTS];
struct list_head clients;

struct vga_switcheroo_handler *handler;
};
Expand All @@ -62,7 +63,9 @@ 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;
static struct vgasr_priv vgasr_priv = {
.clients = LIST_HEAD_INIT(vgasr_priv.clients),
};

int vga_switcheroo_register_handler(struct vga_switcheroo_handler *handler)
{
Expand All @@ -88,17 +91,18 @@ EXPORT_SYMBOL(vga_switcheroo_unregister_handler);

static void vga_switcheroo_enable(void)
{
int i;
int ret;
struct vga_switcheroo_client *client;

/* 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);
list_for_each_entry(client, &vgasr_priv.clients, list) {
ret = vgasr_priv.handler->get_client_id(client->pdev);
if (ret < 0)
return;

vgasr_priv.clients[i].id = ret;
client->id = ret;
}
vga_switcheroo_debugfs_init(&vgasr_priv);
vgasr_priv.active = true;
Expand All @@ -109,28 +113,27 @@ int vga_switcheroo_register_client(struct pci_dev *pdev,
void (*reprobe)(struct pci_dev *pdev),
bool (*can_switch)(struct pci_dev *pdev))
{
int index;
struct vga_switcheroo_client *client;

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;
client = kzalloc(sizeof(*client), GFP_KERNEL);
if (!client)
return -ENOMEM;

client->pwr_state = VGA_SWITCHEROO_ON;
client->pdev = pdev;
client->set_gpu_state = set_gpu_state;
client->reprobe = reprobe;
client->can_switch = can_switch;
client->id = -1;
if (pdev == vga_default_device())
vgasr_priv.clients[index].active = true;
client->active = true;

vgasr_priv.registered_clients |= (1 << index);
mutex_lock(&vgasr_mutex);
list_add_tail(&client->list, &vgasr_priv.clients);
vgasr_priv.registered_clients++;

/* if we get two clients + handler */
if (vgasr_priv.registered_clients == 0x3 && vgasr_priv.handler) {
if (vgasr_priv.registered_clients == 2 && vgasr_priv.handler) {
printk(KERN_INFO "vga_switcheroo: enabled\n");
vga_switcheroo_enable();
}
Expand All @@ -139,18 +142,47 @@ int vga_switcheroo_register_client(struct pci_dev *pdev,
}
EXPORT_SYMBOL(vga_switcheroo_register_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 == true)
return client;
return NULL;
}

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

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;
}
client = find_client_from_pci(&vgasr_priv.clients, pdev);
if (client) {
list_del(&client->list);
kfree(client);
vgasr_priv.registered_clients--;
}

printk(KERN_INFO "vga_switcheroo: disabled\n");
vga_switcheroo_debugfs_fini(&vgasr_priv);
vgasr_priv.active = false;
Expand All @@ -161,29 +193,28 @@ EXPORT_SYMBOL(vga_switcheroo_unregister_client);
void vga_switcheroo_client_fb_set(struct pci_dev *pdev,
struct fb_info *info)
{
int i;
struct vga_switcheroo_client *client;

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;
}
}
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)
{
int i;
struct vga_switcheroo_client *client;
int i = 0;
mutex_lock(&vgasr_mutex);
for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) {
list_for_each_entry(client, &vgasr_priv.clients, list) {
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));
client->id == VGA_SWITCHEROO_DIS ? "DIS" : "IGD",
client->active ? '+' : ' ',
client->pwr_state ? "Pwr" : "Off",
pci_name(client->pdev));
i++;
}
mutex_unlock(&vgasr_mutex);
return 0;
Expand Down Expand Up @@ -217,15 +248,9 @@ static int vga_switchoff(struct vga_switcheroo_client *client)
/* stage one happens before delay */
static int vga_switchto_stage1(struct vga_switcheroo_client *new_client)
{
int i;
struct vga_switcheroo_client *active = NULL;
struct vga_switcheroo_client *active;

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

Expand All @@ -241,15 +266,9 @@ static int vga_switchto_stage1(struct vga_switcheroo_client *new_client)
static int vga_switchto_stage2(struct vga_switcheroo_client *new_client)
{
int ret;
int i;
struct vga_switcheroo_client *active = NULL;
struct vga_switcheroo_client *active;

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

Expand All @@ -275,13 +294,26 @@ static int vga_switchto_stage2(struct vga_switcheroo_client *new_client)
return 0;
}

static bool check_can_switch(void)
{
struct vga_switcheroo_client *client;

list_for_each_entry(client, &vgasr_priv.clients, list) {
if (!client->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 i, ret;
int ret;
bool delay = false, can_switch;
bool just_mux = false;
int client_id = -1;
Expand All @@ -302,21 +334,21 @@ vga_switcheroo_debugfs_write(struct file *filp, const char __user *ubuf,

/* 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)
list_for_each_entry(client, &vgasr_priv.clients, list) {
if (client->active)
continue;
if (vgasr_priv.clients[i].pwr_state == VGA_SWITCHEROO_ON)
vga_switchoff(&vgasr_priv.clients[i]);
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) {
for (i = 0; i < VGA_SWITCHEROO_MAX_CLIENTS; i++) {
if (vgasr_priv.clients[i].active)
list_for_each_entry(client, &vgasr_priv.clients, list) {
if (client->active)
continue;
if (vgasr_priv.clients[i].pwr_state == VGA_SWITCHEROO_OFF)
vga_switchon(&vgasr_priv.clients[i]);
if (client->pwr_state == VGA_SWITCHEROO_OFF)
vga_switchon(client);
}
goto out;
}
Expand Down Expand Up @@ -349,13 +381,9 @@ vga_switcheroo_debugfs_write(struct file *filp, const char __user *ubuf,

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;
}
}
client = find_client_from_id(&vgasr_priv.clients, client_id);
if (!client)
goto out;

vgasr_priv.delayed_switch_active = false;

Expand All @@ -364,23 +392,16 @@ vga_switcheroo_debugfs_write(struct file *filp, const char __user *ubuf,
goto out;
}

if (client->active == true)
if (client->active)
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;
}
}
can_switch = check_can_switch();

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

if (can_switch == true) {
if (can_switch) {
pdev_name = pci_name(client->pdev);
ret = vga_switchto_stage1(client);
if (ret)
Expand Down Expand Up @@ -452,10 +473,8 @@ static int vga_switcheroo_debugfs_init(struct vgasr_priv *priv)

int vga_switcheroo_process_delayed_switch(void)
{
struct vga_switcheroo_client *client = NULL;
struct vga_switcheroo_client *client;
const char *pdev_name;
bool can_switch = true;
int i;
int ret;
int err = -EINVAL;

Expand All @@ -465,17 +484,9 @@ int vga_switcheroo_process_delayed_switch(void)

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)
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);
Expand Down

0 comments on commit 79721e0

Please sign in to comment.