[PATCH 1/2] vga_switcheroo: Refactor using linked list
Takashi Iwai
tiwai at suse.de
Thu May 10 00:09:29 PDT 2012
Refactor the code base a bit for the further work to adapt more clients.
Signed-off-by: Takashi Iwai <tiwai at suse.de>
---
drivers/gpu/vga/vga_switcheroo.c | 209 ++++++++++++++++++++------------------
1 file changed, 110 insertions(+), 99 deletions(-)
diff --git a/drivers/gpu/vga/vga_switcheroo.c b/drivers/gpu/vga/vga_switcheroo.c
index 58434e8..c91573f 100644
--- a/drivers/gpu/vga/vga_switcheroo.c
+++ b/drivers/gpu/vga/vga_switcheroo.c
@@ -37,6 +37,7 @@ struct vga_switcheroo_client {
bool (*can_switch)(struct pci_dev *pdev);
int id;
bool active;
+ struct list_head list;
};
static DEFINE_MUTEX(vgasr_mutex);
@@ -51,7 +52,7 @@ 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;
};
@@ -60,7 +61,9 @@ 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)
{
@@ -86,17 +89,18 @@ 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;
@@ -107,28 +111,27 @@ 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->resource[PCI_ROM_RESOURCE].flags & IORESOURCE_ROM_SHADOW)
- 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();
}
@@ -137,18 +140,47 @@ 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;
@@ -159,29 +191,28 @@ 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;
@@ -215,15 +246,9 @@ 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;
@@ -240,15 +265,9 @@ 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;
@@ -274,13 +293,26 @@ 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;
@@ -301,21 +333,21 @@ 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;
}
@@ -348,13 +380,9 @@ 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;
@@ -363,23 +391,16 @@ 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)
@@ -451,10 +472,8 @@ fail:
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;
@@ -464,17 +483,9 @@ 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);
--
1.7.9.2
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