1 files changed, 453 insertions, 0 deletions

diff --git a/drivers/gpu/vga/vga_switcheroo.c b/drivers/gpu/vga/vga_switcheroo.c
new file mode 100644
index 000000000000..a3f587a0aba9
--- /dev/null
+++ b/drivers/gpu/vga/vga_switcheroo.c
@@ -0,0 +1,453 @@
+/*
+ * 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 <acpi/acpi.h>
+#include <acpi/acpi_bus.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)
+                return -EINVAL;
+
+        /* 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);
+