[PATCH v2 08/22] Revert "vga_switcheroo: add reprobe hook for fbcon to recheck connected outputs."

[Lukas Wunner]

This reverts commit 8d608aa6295242fe4c4b6105b8c59c6a5b232d89.

Reprobing must happen asynchronously as the driver may grab vgasr_mutex
when invoking vga_switcheroo_client_fb_set(), when locking the DDC lines
or when using the upcoming DDC/AUX proxy functionality. And that lock is
already held in stage2 by vga_switcheroo_debugfs_write().

Infrastructure for asynchronous reprobing is added to vga_switcheroo
with a subsequent commit and could easily be used in stage2, but:

- The ->reprobe callback was only ever used by a single driver, nouveau.

- Drivers need to reprobe their outputs anyway after waking up, this is
  nothing specific to dual GPU laptops and should be added to the resume
  code of the driver.

- It would seem there's no need anymore to delay reprobing until after
  switching the mux: We have two methods now to make reprobing work with
  the display not switched (switching only the DDC lines and proxying),
  at least one of them should always work.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=88861
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=61115
Tested-by: Paul Hordiienko <pvt.gord at gmail.com>
    [MBP  6,2 2010  intel ILK + nvidia GT216  pre-retina]
Tested-by: William Brown <william at blackhats.net.au>
    [MBP  8,2 2011  intel SNB + amd turks     pre-retina]
Tested-by: Lukas Wunner <lukas at wunner.de>
    [MBP  9,1 2012  intel IVB + nvidia GK107  pre-retina]
Tested-by: Bruno Bierbaumer <bruno at bierbaumer.net>
    [MBP 11,3 2013  intel HSW + nvidia GK107  retina -- work in progress]

Signed-off-by: Lukas Wunner <lukas at wunner.de>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 1 -
 drivers/gpu/drm/i915/i915_dma.c            | 1 -
 drivers/gpu/drm/nouveau/nouveau_vga.c      | 8 --------
 drivers/gpu/drm/radeon/radeon_device.c     | 1 -
 drivers/gpu/vga/vga_switcheroo.c           | 3 ---
 include/linux/vga_switcheroo.h             | 1 -
 6 files changed, 15 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index d79009b..55c8d51 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -1076,7 +1076,6 @@ static bool amdgpu_switcheroo_can_switch(struct pci_dev *pdev)
 
 static const struct vga_switcheroo_client_ops amdgpu_switcheroo_ops = {
 	.set_gpu_state = amdgpu_switcheroo_set_state,
-	.reprobe = NULL,
 	.can_switch = amdgpu_switcheroo_can_switch,
 };
 
diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index b1f9e55..c240944 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -388,7 +388,6 @@ static bool i915_switcheroo_can_switch(struct pci_dev *pdev)
 
 static const struct vga_switcheroo_client_ops i915_switcheroo_ops = {
 	.set_gpu_state = i915_switcheroo_set_state,
-	.reprobe = NULL,
 	.can_switch = i915_switcheroo_can_switch,
 };
 
diff --git a/drivers/gpu/drm/nouveau/nouveau_vga.c b/drivers/gpu/drm/nouveau/nouveau_vga.c
index c7592ec..42779f4 100644
--- a/drivers/gpu/drm/nouveau/nouveau_vga.c
+++ b/drivers/gpu/drm/nouveau/nouveau_vga.c
@@ -55,13 +55,6 @@ nouveau_switcheroo_set_state(struct pci_dev *pdev,
 	}
 }
 
-static void
-nouveau_switcheroo_reprobe(struct pci_dev *pdev)
-{
-	struct drm_device *dev = pci_get_drvdata(pdev);
-	nouveau_fbcon_output_poll_changed(dev);
-}
-
 static bool
 nouveau_switcheroo_can_switch(struct pci_dev *pdev)
 {
@@ -78,7 +71,6 @@ nouveau_switcheroo_can_switch(struct pci_dev *pdev)
 static const struct vga_switcheroo_client_ops
 nouveau_switcheroo_ops = {
 	.set_gpu_state = nouveau_switcheroo_set_state,
-	.reprobe = nouveau_switcheroo_reprobe,
 	.can_switch = nouveau_switcheroo_can_switch,
 };
 
diff --git a/drivers/gpu/drm/radeon/radeon_device.c b/drivers/gpu/drm/radeon/radeon_device.c
index d8319da..2cb513f 100644
--- a/drivers/gpu/drm/radeon/radeon_device.c
+++ b/drivers/gpu/drm/radeon/radeon_device.c
@@ -1258,7 +1258,6 @@ static bool radeon_switcheroo_can_switch(struct pci_dev *pdev)
 
 static const struct vga_switcheroo_client_ops radeon_switcheroo_ops = {
 	.set_gpu_state = radeon_switcheroo_set_state,
-	.reprobe = NULL,
 	.can_switch = radeon_switcheroo_can_switch,
 };
 
diff --git a/drivers/gpu/vga/vga_switcheroo.c b/drivers/gpu/vga/vga_switcheroo.c
index f0d5475..8027c9f 100644
--- a/drivers/gpu/vga/vga_switcheroo.c
+++ b/drivers/gpu/vga/vga_switcheroo.c
@@ -440,9 +440,6 @@ static int vga_switchto_stage2(struct vga_switcheroo_client *new_client)
 		return ret;
 	}
 
-	if (new_client->ops->reprobe)
-		new_client->ops->reprobe(new_client->pdev);
-
 	if (active->pwr_state == VGA_SWITCHEROO_ON)
 		vga_switchoff(active);
 
diff --git a/include/linux/vga_switcheroo.h b/include/linux/vga_switcheroo.h
index 62f303f..b935d83 100644
--- a/include/linux/vga_switcheroo.h
+++ b/include/linux/vga_switcheroo.h
@@ -39,7 +39,6 @@ struct vga_switcheroo_handler {
 
 struct vga_switcheroo_client_ops {
 	void (*set_gpu_state)(struct pci_dev *dev, enum vga_switcheroo_state);
-	void (*reprobe)(struct pci_dev *dev);
 	bool (*can_switch)(struct pci_dev *dev);
 };
 
-- 
1.8.5.2 (Apple Git-48)