vga_switcheroo: initial implementation (v15)

Many new laptops now come with 2 gpus, one to be used for low power
modes and one for gaming/on-ac applications. These GPUs are typically
wired to the laptop panel and VGA ports via a multiplexer unit which
is controlled via ACPI methods.

4 combinations of systems typically exist - with 2 ACPI methods.
Intel/ATI - Lenovo W500/T500 - use ATPX ACPI method
ATI/ATI - some ASUS - use ATPX ACPI Method
Intel/Nvidia - - use _DSM ACPI method
Nvidia/Nvidia -  - use _DSM ACPI method.

TODO:
This patch adds support for the ATPX method and initial bits
for the _DSM methods that need to written by someone with
access to the hardware.
Add a proper non-debugfs interface - need to get some proper
testing first.

v2: add power up/down support for both devices
on W500 puts i915/radeon into D3 and cuts power to radeon.

v3: redo probing methods, no DMI list, drm devices call to
register with switcheroo, it tries to find an ATPX method on
any device and once there is two devices + ATPX it inits the
switcher.

v4: ATPX msg handling using buffers - should work on more machines

v5: rearchitect after more mjg59 discussion - move ATPX handling to
    radeon driver.

v6: add file headers + initial nouveau bits (to be filled out).

v7: merge delayed switcher code.

v8: avoid suspend/resume of gpu that is off

v9: rearchitect - mjg59 is always right. - move all ATPX code to
radeon, should allow simpler DSM also proper ATRM handling

v10: add ATRM support for radeon BIOS, add mutex to lock vgasr_priv

v11: fix bug in resuming Intel for 2nd time.

v12: start fixing up nvidia code blindly.

v13: blindly guess at finishing nvidia code

v14: remove radeon audio hacks - fix up intel resume more like upstream

v15: clean up printks + remove unnecessary igd/dis pointers

mount debugfs

/sys/kernel/debug/vgaswitcheroo/switch - should exist if ATPX detected
 + 2 cards.

DIS - immediate change to discrete
IGD - immediate change to IGD
DDIS - delayed change to discrete
DIGD - delayed change to IGD
ON - turn on not in use
OFF - turn off not in use

Tested on W500 (Intel/ATI) and T500 (Intel/ATI)

Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 5 insertions, 14 deletions

diff --git a/drivers/gpu/drm/nouveau/nouveau_drv.h b/drivers/gpu/drm/nouveau/nouveau_drv.h
index 1c15ef37b71c..85c05feab4f0 100644
--- a/drivers/gpu/drm/nouveau/nouveau_drv.h
+++ b/drivers/gpu/drm/nouveau/nouveau_drv.h
@@ -614,7 +614,6 @@ struct drm_nouveau_private {
 	} susres;
 
 	struct backlight_device *backlight;
-	bool acpi_dsm;
 
 	struct nouveau_channel *evo;
 
@@ -682,6 +681,9 @@ extern int nouveau_ignorelid;
 extern int nouveau_nofbaccel;
 extern int nouveau_noaccel;
 
+extern int nouveau_pci_suspend(struct pci_dev *pdev, pm_message_t pm_state);
+extern int nouveau_pci_resume(struct pci_dev *pdev);
+
 /* nouveau_state.c */
 extern void nouveau_preclose(struct drm_device *dev, struct drm_file *);
 extern int  nouveau_load(struct drm_device *, unsigned long flags);
@@ -848,19 +850,8 @@ extern int  nouveau_dma_init(struct nouveau_channel *);
 extern int  nouveau_dma_wait(struct nouveau_channel *, int size);
 
 /* nouveau_acpi.c */
-#ifdef CONFIG_ACPI
-extern int nouveau_hybrid_setup(struct drm_device *dev);
-extern bool nouveau_dsm_probe(struct drm_device *dev);
-#else
-static inline int nouveau_hybrid_setup(struct drm_device *dev)
-{
-	return 0;
-}
-static inline bool nouveau_dsm_probe(struct drm_device *dev)
-{
-	return false;
-}
-#endif
+void nouveau_register_dsm_handler(void);
+void nouveau_unregister_dsm_handler(void);
 
 /* nouveau_backlight.c */
 #ifdef CONFIG_DRM_NOUVEAU_BACKLIGHT