Saves the current state of the mux and restores it upon resume from hibernation.
This is needed for muxed systems because the state of the mux doesn't survive a
hibernation-resume cycle. Furthermore also restores the power state of a GPU
to OFF after resume from hibernation if it was OFF before hibernation.
Signed-off-by: Stefan Demharter <stefan.demharter at gmx.net>
---
drivers/gpu/vga/vga_switcheroo.c | 96 +++++++++++++++++++++++++++++++++++-----
1 file changed, 85 insertions(+), 11 deletions(-)
diff --git a/drivers/gpu/vga/vga_switcheroo.c b/drivers/gpu/vga/vga_switcheroo.c
index ec0ae2d..85f41b9 100644
--- a/drivers/gpu/vga/vga_switcheroo.c
+++ b/drivers/gpu/vga/vga_switcheroo.c
@@ -28,6 +28,7 @@
#include <linux/console.h>
#include <linux/vga_switcheroo.h>
#include <linux/pm_runtime.h>
+#include <linux/suspend.h>
#include <linux/vgaarb.h>
@@ -72,6 +73,64 @@ static struct vgasr_priv vgasr_priv = {
.clients = LIST_HEAD_INIT(vgasr_priv.clients),
};
+#define MUX_STATE_UNDEFINED (-1)
+/*
+ * The next variable stores the state of the mux
+ * so it can be restored upon resume from hibernation.
+ */
+static int mux_state = MUX_STATE_UNDEFINED;
+
+static void vga_restore_mux(void)
+{
+ if (mux_state != MUX_STATE_UNDEFINED) {
+ int ret;
+ pr_info("vga_switcheroo: restoring mux state to %s\n",
+ mux_state == VGA_SWITCHEROO_IGD ? "IGD" : "DIS");
+
+ ret = vgasr_priv.handler->switchto(mux_state);
+ if (ret)
+ pr_warn("vga_switcheroo: mux switch failed (%d)\n",
ret);
+ }
+}
+
+static void vga_restore_power_state(void)
+{
+ struct vga_switcheroo_client *client;
+
+ if (!vgasr_priv.handler->power_state)
+ return;
+
+ list_for_each_entry(client, &vgasr_priv.clients, list) {
+ if (client_is_vga(client) && client->pwr_state ==
VGA_SWITCHEROO_OFF) {
+ pr_info("vga_switcheroo: setting power state of %s to
OFF\n",
+ client->id == VGA_SWITCHEROO_IGD ? "IGD" :
"DIS");
+ vgasr_priv.handler->power_state(client->id,
client->pwr_state);
+ }
+ }
+}
+
+/*
+ * Handle resume from hibernation:
+ * Restore mux state and power states for switcheroo controlled GPUs.
+ */
+static int vga_resume(struct notifier_block *nb, unsigned long action, void
*unused)
+{
+ switch (action) {
+ case PM_POST_HIBERNATION:
+ mutex_lock(&vgasr_mutex);
+ vga_restore_mux();
+ vga_restore_power_state();
+ mutex_unlock(&vgasr_mutex);
+ break;
+ }
+ return 0;
+}
+
+static struct notifier_block vga_switcheroo_pm_nb = {
+ .notifier_call = vga_resume,
+ .priority = 0,
+};
+
static bool vga_switcheroo_ready(void)
{
/* we're ready if we get two clients + handler */
@@ -84,6 +143,8 @@ static void vga_switcheroo_enable(void)
int ret;
struct vga_switcheroo_client *client;
+ pr_info("vga_switcheroo: enabled\n");
+
/* call the handler to init */
if (vgasr_priv.handler->init)
vgasr_priv.handler->init();
@@ -99,6 +160,15 @@ static void vga_switcheroo_enable(void)
}
vga_switcheroo_debugfs_init(&vgasr_priv);
vgasr_priv.active = true;
+ register_pm_notifier(&vga_switcheroo_pm_nb);
+}
+
+void vga_switcheroo_disable(void)
+{
+ unregister_pm_notifier(&vga_switcheroo_pm_nb);
+ vgasr_priv.active = false;
+ vga_switcheroo_debugfs_fini(&vgasr_priv);
+ pr_info("vga_switcheroo: disabled\n");
}
int vga_switcheroo_register_handler(struct vga_switcheroo_handler *handler)
@@ -111,7 +181,6 @@ int vga_switcheroo_register_handler(struct
vga_switcheroo_handler *handler)
vgasr_priv.handler = handler;
if (vga_switcheroo_ready()) {
- printk(KERN_INFO "vga_switcheroo: enabled\n");
vga_switcheroo_enable();
}
mutex_unlock(&vgasr_mutex);
@@ -124,9 +193,7 @@ 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;
+ vga_switcheroo_disable();
}
mutex_unlock(&vgasr_mutex);
}
@@ -155,7 +222,6 @@ static int register_client(struct pci_dev *pdev,
vgasr_priv.registered_clients++;
if (vga_switcheroo_ready()) {
- printk(KERN_INFO "vga_switcheroo: enabled\n");
vga_switcheroo_enable();
}
mutex_unlock(&vgasr_mutex);
@@ -235,9 +301,7 @@ void vga_switcheroo_unregister_client(struct pci_dev *pdev)
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;
+ vga_switcheroo_disable();
}
mutex_unlock(&vgasr_mutex);
}
@@ -262,10 +326,11 @@ static int vga_switcheroo_show(struct seq_file *m, void
*v)
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,
+ seq_printf(m, "%d:%s%s:%c%s:%s%s:%s\n", i,
client_id(client) == VGA_SWITCHEROO_DIS ? "DIS" :
"IGD",
client_is_vga(client) ? "" : "-Audio",
client->active ? '+' : ' ',
+ client_id(client) == mux_state ? "mux" : "",
client->driver_power_control ? "Dyn" : "",
client->pwr_state ? "Pwr" : "Off",
pci_name(client->pdev));
@@ -304,6 +369,15 @@ static int vga_switchoff(struct vga_switcheroo_client
*client)
return 0;
}
+static int vga_switchto(int client_id)
+{
+ int ret = vgasr_priv.handler->switchto(client_id);
+
+ if (ret == 0)
+ mux_state = client_id;
+ return ret;
+}
+
static void set_audio_state(int id, int state)
{
struct vga_switcheroo_client *client;
@@ -353,7 +427,7 @@ static int vga_switchto_stage2(struct vga_switcheroo_client
*new_client)
console_unlock();
}
- ret = vgasr_priv.handler->switchto(new_client->id);
+ ret = vga_switchto(new_client->id);
if (ret)
return ret;
@@ -468,7 +542,7 @@ vga_switcheroo_debugfs_write(struct file *filp, const char
__user *ubuf,
vgasr_priv.delayed_switch_active = false;
if (just_mux) {
- ret = vgasr_priv.handler->switchto(client_id);
+ ret = vga_switchto(client_id);
goto out;
}
--
1.8.5.3
