[PATCH v2 10/11] drm/tidss: Fix atomic_flush check

From: Tomi Valkeinen
Date: Thu Nov 09 2023 - 02:39:54 EST


tidss_crtc_atomic_flush() checks if the crtc is enabled, and if not,
returns immediately as there's no reason to do any register changes.

However, the code checks for 'crtc->state->enable', which does not
reflect the actual HW state. We should instead look at the
'crtc->state->active' flag.

This causes the tidss_crtc_atomic_flush() to proceed with the flush even
if the active state is false, which then causes us to hit the
WARN_ON(!crtc->state->event) check.

Fix this by checking the active flag, and while at it, fix the related
debug print which had "active" and "needs modeset" wrong way.

Cc: stable@xxxxxxxxxxxxxxx
Fixes: 32a1795f57ee ("drm/tidss: New driver for TI Keystone platform Display SubSystem")
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/tidss/tidss_crtc.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/tidss/tidss_crtc.c b/drivers/gpu/drm/tidss/tidss_crtc.c
index 5e5e466f35d1..7c78c074e3a2 100644
--- a/drivers/gpu/drm/tidss/tidss_crtc.c
+++ b/drivers/gpu/drm/tidss/tidss_crtc.c
@@ -169,13 +169,13 @@ static void tidss_crtc_atomic_flush(struct drm_crtc *crtc,
struct tidss_device *tidss = to_tidss(ddev);
unsigned long flags;

- dev_dbg(ddev->dev,
- "%s: %s enabled %d, needs modeset %d, event %p\n", __func__,
- crtc->name, drm_atomic_crtc_needs_modeset(crtc->state),
- crtc->state->enable, crtc->state->event);
+ dev_dbg(ddev->dev, "%s: %s is %sactive, %s modeset, event %p\n",
+ __func__, crtc->name, crtc->state->active ? "" : "not ",
+ drm_atomic_crtc_needs_modeset(crtc->state) ? "needs" : "doesn't need",
+ crtc->state->event);

/* There is nothing to do if CRTC is not going to be enabled. */
- if (!crtc->state->enable)
+ if (!crtc->state->active)
return;

/*

--
2.34.1