[src/trunk]: src/sys/external/bsd/drm2/dist/drm/i915 Merge https://github.com...

[jmcneill <jmcneill%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/2d1915ee6dd1
branches:  trunk
changeset: 333430:2d1915ee6dd1
user:      jmcneill <jmcneill%NetBSD.org@localhost>
date:      Tue Nov 04 03:05:36 2014 +0000

description:
Merge https://github.com/torvalds/linux/commit/2e7eeeb59a92d09144fdb7d2dc1af77a10a7945b#diff-528092536eaeb3c5f7ff6dfeed53786d

> drm/i915: set backlight duty cycle after backlight enable for gen4
> For reasons I can't claim to fully understand gen4 seems to require
> backlight duty cycle setting after the backlight has been enabled, or
> else black screen follows. I don't have documentation for the correct
> sequence on gen4 either. Confirmed on Dell Latitude D630 and MacBook4,1.

Without this patch, the screen on my T61 (i965) would be blank at boot
unless I booted with the AC adapter unplugged.

diffstat:

 sys/external/bsd/drm2/dist/drm/i915/intel_panel.c |  5 ++---
 1 files changed, 2 insertions(+), 3 deletions(-)

diffs (22 lines):

diff -r 531e8317ac16 -r 2d1915ee6dd1 sys/external/bsd/drm2/dist/drm/i915/intel_panel.c
--- a/sys/external/bsd/drm2/dist/drm/i915/intel_panel.c Tue Nov 04 00:20:19 2014 +0000
+++ b/sys/external/bsd/drm2/dist/drm/i915/intel_panel.c Tue Nov 04 03:05:36 2014 +0000
@@ -730,9 +730,6 @@
        ctl = freq << 16;
        I915_WRITE(BLC_PWM_CTL, ctl);
 
-       /* XXX: combine this into above write? */
-       intel_panel_actually_set_backlight(connector, panel->backlight.level);
-
        ctl2 = BLM_PIPE(pipe);
        if (panel->backlight.combination_mode)
                ctl2 |= BLM_COMBINATION_MODE;
@@ -741,6 +738,8 @@
        I915_WRITE(BLC_PWM_CTL2, ctl2);
        POSTING_READ(BLC_PWM_CTL2);
        I915_WRITE(BLC_PWM_CTL2, ctl2 | BLM_PWM_ENABLE);
+
+       intel_panel_actually_set_backlight(connector, panel->backlight.level);
 }
 
 static void vlv_enable_backlight(struct intel_connector *connector)