--- /dev/null
+/*
+ * 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/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/console.h>
+#include <linux/vga_switcheroo.h>
+#include <linux/pm_runtime.h>
+
+#include <linux/vgaarb.h>
+
+struct vga_switcheroo_client {
+ struct pci_dev *pdev;
+ struct fb_info *fb_info;
+ int pwr_state;
+ const struct vga_switcheroo_client_ops *ops;
+ int id;
+ bool active;
+ bool driver_power_control;
+ struct list_head list;
+};
+
+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 list_head clients;
+
+ struct vga_switcheroo_handler *handler;
+};
+
+#define ID_BIT_AUDIO 0x100
+#define client_is_audio(c) ((c)->id & ID_BIT_AUDIO)
+#define client_is_vga(c) ((c)->id == -1 || !client_is_audio(c))
+#define client_id(c) ((c)->id & ~ID_BIT_AUDIO)
+
+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 = {
+ .clients = LIST_HEAD_INIT(vgasr_priv.clients),
+};
+
+static bool vga_switcheroo_ready(void)
+{
+ /* we're ready if we get two clients + handler */
+ return !vgasr_priv.active &&
+ vgasr_priv.registered_clients == 2 && vgasr_priv.handler;
+}
+
+static void vga_switcheroo_enable(void)
+{
+ int ret;
+ struct vga_switcheroo_client *client;
+
+ /* call the handler to init */
+ if (vgasr_priv.handler->init)
+ vgasr_priv.handler->init();
+
+ list_for_each_entry(client, &vgasr_priv.clients, list) {
+ if (client->id != -1)
+ continue;
+ ret = vgasr_priv.handler->get_client_id(client->pdev);
+ if (ret < 0)
+ return;
+
+ client->id = ret;
+ }
+ vga_switcheroo_debugfs_init(&vgasr_priv);
+ vgasr_priv.active = true;
+}
+
+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;
+ if (vga_switcheroo_ready()) {
+ printk(KERN_INFO "vga_switcheroo: enabled\n");
+ vga_switcheroo_enable();
+ }
+ 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;
+ if (vgasr_priv.active) {
+ pr_info("vga_switcheroo: disabled\n");
+ vga_switcheroo_debugfs_fini(&vgasr_priv);
+ vgasr_priv.active = false;
+ }
+ mutex_unlock(&vgasr_mutex);
+}
+EXPORT_SYMBOL(vga_switcheroo_unregister_handler);
+
+static int register_client(struct pci_dev *pdev,
+ const struct vga_switcheroo_client_ops *ops,
+ int id, bool active, bool driver_power_control)
+{
+ struct vga_switcheroo_client *client;
+
+ client = kzalloc(sizeof(*client), GFP_KERNEL);
+ if (!client)
+ return -ENOMEM;
+
+ client->pwr_state = VGA_SWITCHEROO_ON;
+ client->pdev = pdev;
+ client->ops = ops;
+ client->id = id;
+ client->active = active;
+ client->driver_power_control = driver_power_control;
+
+ mutex_lock(&vgasr_mutex);
+ list_add_tail(&client->list, &vgasr_priv.clients);
+ if (client_is_vga(client))
+ vgasr_priv.registered_clients++;
+
+ if (vga_switcheroo_ready()) {
+ printk(KERN_INFO "vga_switcheroo: enabled\n");
+ vga_switcheroo_enable();
+ }
+ mutex_unlock(&vgasr_mutex);
+ return 0;
+}
+
+int vga_switcheroo_register_client(struct pci_dev *pdev,
+ const struct vga_switcheroo_client_ops *ops,
+ bool driver_power_control)
+{
+ return register_client(pdev, ops, -1,
+ pdev == vga_default_device(), driver_power_control);
+}
+EXPORT_SYMBOL(vga_switcheroo_register_client);
+
+int vga_switcheroo_register_audio_client(struct pci_dev *pdev,
+ const struct vga_switcheroo_client_ops *ops,
+ int id, bool active)
+{
+ return register_client(pdev, ops, id | ID_BIT_AUDIO, active, false);
+}
+EXPORT_SYMBOL(vga_switcheroo_register_audio_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 && client_is_vga(client))
+ return client;
+ return NULL;
+}
+
+int vga_switcheroo_get_client_state(struct pci_dev *pdev)
+{
+ struct vga_switcheroo_client *client;
+
+ client = find_client_from_pci(&vgasr_priv.clients, pdev);
+ if (!client)
+ return VGA_SWITCHEROO_NOT_FOUND;
+ if (!vgasr_priv.active)
+ return VGA_SWITCHEROO_INIT;
+ return client->pwr_state;
+}
+EXPORT_SYMBOL(vga_switcheroo_get_client_state);
+
+void vga_switcheroo_unregister_client(struct pci_dev *pdev)
+{
+ struct vga_switcheroo_client *client;
+
+ mutex_lock(&vgasr_mutex);
+ client = find_client_from_pci(&vgasr_priv.clients, pdev);
+ if (client) {
+ if (client_is_vga(client))
+ vgasr_priv.registered_clients--;
+ list_del(&client->list);
+ kfree(client);
+ }
+ if (vgasr_priv.active && vgasr_priv.registered_clients < 2) {
+ 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)
+{
+ struct vga_switcheroo_client *client;
+
+ mutex_lock(&vgasr_mutex);
+ 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)
+{
+ struct vga_switcheroo_client *client;
+ int i = 0;
+ mutex_lock(&vgasr_mutex);
+ list_for_each_entry(client, &vgasr_priv.clients, list) {
+ seq_printf(m, "%d:%s%s:%c:%s%s:%s\n", i,
+ client_id(client) == VGA_SWITCHEROO_DIS ? "DIS" : "IGD",
+ client_is_vga(client) ? "" : "-Audio",
+ client->active ? '+' : ' ',
+ client->driver_power_control ? "Dyn" : "",
+ client->pwr_state ? "Pwr" : "Off",
+ pci_name(client->pdev));
+ i++;
+ }
+ 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 (client->driver_power_control)
+ return 0;
+ 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->ops->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)
+{
+ if (client->driver_power_control)
+ return 0;
+ /* call the driver callback to turn off device */
+ client->ops->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 void set_audio_state(int id, int state)
+{
+ struct vga_switcheroo_client *client;
+
+ client = find_client_from_id(&vgasr_priv.clients, id | ID_BIT_AUDIO);
+ if (client && client->pwr_state != state) {
+ client->ops->set_gpu_state(client->pdev, state);
+ client->pwr_state = state;
+ }
+}
+
+/* stage one happens before delay */
+static int vga_switchto_stage1(struct vga_switcheroo_client *new_client)
+{
+ struct vga_switcheroo_client *active;
+
+ active = find_active_client(&vgasr_priv.clients);
+ if (!active)
+ return 0;
+
+ if (new_client->pwr_state == VGA_SWITCHEROO_OFF)
+ vga_switchon(new_client);
+
+ vga_set_default_device(new_client->pdev);
+ return 0;
+}
+
+/* post delay */
+static int vga_switchto_stage2(struct vga_switcheroo_client *new_client)
+{
+ int ret;
+ struct vga_switcheroo_client *active;
+
+ active = find_active_client(&vgasr_priv.clients);
+ if (!active)
+ return 0;
+
+ active->active = false;
+
+ set_audio_state(active->id, VGA_SWITCHEROO_OFF);
+
+ if (new_client->fb_info) {
+ struct fb_event event;
+ console_lock();
+ event.info = new_client->fb_info;
+ fb_notifier_call_chain(FB_EVENT_REMAP_ALL_CONSOLE, &event);
+ console_unlock();
+ }
+
+ ret = vgasr_priv.handler->switchto(new_client->id);
+ if (ret)
+ return ret;
+
+ if (new_client->ops->reprobe)
+ new_client->ops->reprobe(new_client->pdev);
+
+ if (active->pwr_state == VGA_SWITCHEROO_ON)
+ vga_switchoff(active);
+
+ set_audio_state(new_client->id, VGA_SWITCHEROO_ON);
+
+ new_client->active = true;
+ return 0;
+}
+
+static bool check_can_switch(void)
+{
+ struct vga_switcheroo_client *client;
+
+ list_for_each_entry(client, &vgasr_priv.clients, list) {
+ if (!client->ops->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];
+ int 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) {
+ list_for_each_entry(client, &vgasr_priv.clients, list) {
+ if (client->active || client_is_audio(client))
+ continue;
+ if (client->driver_power_control)
+ continue;
+ set_audio_state(client->id, VGA_SWITCHEROO_OFF);
+ 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) {
+ list_for_each_entry(client, &vgasr_priv.clients, list) {
+ if (client->active || client_is_audio(client))
+ continue;
+ if (client->driver_power_control)
+ continue;
+ if (client->pwr_state == VGA_SWITCHEROO_OFF)
+ vga_switchon(client);
+ set_audio_state(client->id, VGA_SWITCHEROO_ON);
+ }
+ 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", 4) == 0) {
+ just_mux = true;
+ client_id = VGA_SWITCHEROO_IGD;
+ }
+ if (strncmp(usercmd, "MDIS", 4) == 0) {
+ just_mux = true;
+ client_id = VGA_SWITCHEROO_DIS;
+ }
+
+ if (client_id == -1)
+ goto out;
+ client = find_client_from_id(&vgasr_priv.clients, client_id);
+ if (!client)
+ goto out;
+
+ vgasr_priv.delayed_switch_active = false;
+
+ if (just_mux) {
+ ret = vgasr_priv.handler->switchto(client_id);
+ goto out;
+ }
+
+ if (client->active)
+ goto out;
+
+ /* okay we want a switch - test if devices are willing to switch */
+ can_switch = check_can_switch();
+
+ if (can_switch == false && delay == false)
+ goto out;
+
+ if (can_switch) {
+ ret = vga_switchto_stage1(client);
+ if (ret)
+ printk(KERN_ERR "vga_switcheroo: switching failed stage 1 %d\n", ret);
+
+ ret = vga_switchto_stage2(client);
+ if (ret)
+ printk(KERN_ERR "vga_switcheroo: switching failed stage 2 %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;
+
+ ret = vga_switchto_stage1(client);
+ if (ret)
+ printk(KERN_ERR "vga_switcheroo: delayed switching stage 1 failed %d\n", ret);
+ }
+
+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;
+ 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);
+
+ client = find_client_from_id(&vgasr_priv.clients,
+ vgasr_priv.delayed_client_id);
+ if (!client || !check_can_switch())
+ goto err;
+
+ ret = vga_switchto_stage2(client);
+ if (ret)
+ printk(KERN_ERR "vga_switcheroo: delayed switching failed stage 2 %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);
+
+static void vga_switcheroo_power_switch(struct pci_dev *pdev, enum vga_switcheroo_state state)
+{
+ struct vga_switcheroo_client *client;
+
+ if (!vgasr_priv.handler->power_state)
+ return;
+
+ client = find_client_from_pci(&vgasr_priv.clients, pdev);
+ if (!client)
+ return;
+
+ if (!client->driver_power_control)
+ return;
+
+ vgasr_priv.handler->power_state(client->id, state);
+}
+
+/* force a PCI device to a certain state - mainly to turn off audio clients */
+
+void vga_switcheroo_set_dynamic_switch(struct pci_dev *pdev, enum vga_switcheroo_state dynamic)
+{
+ struct vga_switcheroo_client *client;
+
+ client = find_client_from_pci(&vgasr_priv.clients, pdev);
+ if (!client)
+ return;
+
+ if (!client->driver_power_control)
+ return;
+
+ client->pwr_state = dynamic;
+ set_audio_state(client->id, dynamic);
+}
+EXPORT_SYMBOL(vga_switcheroo_set_dynamic_switch);
+
+/* switcheroo power domain */
+static int vga_switcheroo_runtime_suspend(struct device *dev)
+{
+ struct pci_dev *pdev = to_pci_dev(dev);
+ int ret;
+
+ ret = dev->bus->pm->runtime_suspend(dev);
+ if (ret)
+ return ret;
+ if (vgasr_priv.handler->switchto)
+ vgasr_priv.handler->switchto(VGA_SWITCHEROO_IGD);
+ vga_switcheroo_power_switch(pdev, VGA_SWITCHEROO_OFF);
+ return 0;
+}
+
+static int vga_switcheroo_runtime_resume(struct device *dev)
+{
+ struct pci_dev *pdev = to_pci_dev(dev);
+ int ret;
+
+ vga_switcheroo_power_switch(pdev, VGA_SWITCHEROO_ON);
+ ret = dev->bus->pm->runtime_resume(dev);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+/* this version is for the case where the power switch is separate
+ to the device being powered down. */
+int vga_switcheroo_init_domain_pm_ops(struct device *dev, struct dev_pm_domain *domain)
+{
+ /* copy over all the bus versions */
+ if (dev->bus && dev->bus->pm) {
+ domain->ops = *dev->bus->pm;
+ domain->ops.runtime_suspend = vga_switcheroo_runtime_suspend;
+ domain->ops.runtime_resume = vga_switcheroo_runtime_resume;
+
+ dev->pm_domain = domain;
+ return 0;
+ }
+ dev->pm_domain = NULL;
+ return -EINVAL;
+}
+EXPORT_SYMBOL(vga_switcheroo_init_domain_pm_ops);
+
+void vga_switcheroo_fini_domain_pm_ops(struct device *dev)
+{
+ dev->pm_domain = NULL;
+}
+EXPORT_SYMBOL(vga_switcheroo_fini_domain_pm_ops);
+
+static int vga_switcheroo_runtime_resume_hdmi_audio(struct device *dev)
+{
+ struct pci_dev *pdev = to_pci_dev(dev);
+ int ret;
+ struct vga_switcheroo_client *client, *found = NULL;
+
+ /* we need to check if we have to switch back on the video
+ device so the audio device can come back */
+ list_for_each_entry(client, &vgasr_priv.clients, list) {
+ if (PCI_SLOT(client->pdev->devfn) == PCI_SLOT(pdev->devfn) && client_is_vga(client)) {
+ found = client;
+ ret = pm_runtime_get_sync(&client->pdev->dev);
+ if (ret) {
+ if (ret != 1)
+ return ret;
+ }
+ break;
+ }
+ }
+ ret = dev->bus->pm->runtime_resume(dev);
+
+ /* put the reference for the gpu */
+ if (found) {
+ pm_runtime_mark_last_busy(&found->pdev->dev);
+ pm_runtime_put_autosuspend(&found->pdev->dev);
+ }
+ return ret;
+}
+
+int vga_switcheroo_init_domain_pm_optimus_hdmi_audio(struct device *dev, struct dev_pm_domain *domain)
+{
+ /* copy over all the bus versions */
+ if (dev->bus && dev->bus->pm) {
+ domain->ops = *dev->bus->pm;
+ domain->ops.runtime_resume = vga_switcheroo_runtime_resume_hdmi_audio;
+
+ dev->pm_domain = domain;
+ return 0;
+ }
+ dev->pm_domain = NULL;
+ return -EINVAL;
+}
+EXPORT_SYMBOL(vga_switcheroo_init_domain_pm_optimus_hdmi_audio);
Code Review / kvmfornfv.git / blobdiff