Patch "drm/vc4: Move IRQ enable to PM path" has been added to the 4.9-stable tree

Patch "drm/vc4: Move IRQ enable to PM path" has been added to the 4.9-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    drm/vc4: Move IRQ enable to PM path

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     drm-vc4-move-irq-enable-to-pm-path.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Thu Feb  1 14:00:34 CET 2018
From: Stefan Schake <stschake@gmail.com>
Date: Fri, 29 Dec 2017 17:05:43 +0100
Subject: drm/vc4: Move IRQ enable to PM path

From: Stefan Schake <stschake@gmail.com>


[ Upstream commit ce9caf2f79a5aa170a4b6456a03db639eed9c988 ]

We were calling enable_irq on bind, where it was already enabled previously
by the IRQ helper. Additionally, dev->irq is not set correctly until after
postinstall and so was always zero here, triggering a warning in 4.15.
Fix both by moving the enable to the power management resume path, where we
know there was a previous disable invocation during suspend.

Fixes: 253696ccd613 ("drm/vc4: Account for interrupts in flight")
Signed-off-by: Stefan Schake <stschake@gmail.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/1514563543-32511-1-git-send-email-stschake@gmail.com
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/gpu/drm/vc4/vc4_irq.c |    3 ---
 drivers/gpu/drm/vc4/vc4_v3d.c |    3 +++
 2 files changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/gpu/drm/vc4/vc4_irq.c
+++ b/drivers/gpu/drm/vc4/vc4_irq.c
@@ -208,9 +208,6 @@ vc4_irq_postinstall(struct drm_device *d
 {
 	struct vc4_dev *vc4 = to_vc4_dev(dev);
 
-	/* Undo the effects of a previous vc4_irq_uninstall. */
-	enable_irq(dev->irq);
-
 	/* Enable both the render done and out of memory interrupts. */
 	V3D_WRITE(V3D_INTENA, V3D_DRIVER_IRQS);
 
--- a/drivers/gpu/drm/vc4/vc4_v3d.c
+++ b/drivers/gpu/drm/vc4/vc4_v3d.c
@@ -173,6 +173,9 @@ static int vc4_v3d_runtime_resume(struct
 	struct vc4_dev *vc4 = v3d->vc4;
 
 	vc4_v3d_init_hw(vc4->dev);
+
+	/* We disabled the IRQ as part of vc4_irq_uninstall in suspend. */
+	enable_irq(vc4->dev->irq);
 	vc4_irq_postinstall(vc4->dev);
 
 	return 0;


Patches currently in stable-queue which might be from stschake@gmail.com are

queue-4.9/drm-vc4-move-irq-enable-to-pm-path.patch
queue-4.9/drm-vc4-account-for-interrupts-in-flight.patch