2015-01-28 10:11 GMT+01:00 Adrian Chadd <adr...@freebsd.org>: > ugh, so because i can't sleep, I read the Linux i915 history for > backlight changes. > > Turns out if I disable bit 30 in ivb_pch_pwm_override() to register > BLC_PWM_PCH_CTL1, the acpi video setting works. The keyboard settings > still don't, but I'll worry about that later. > > Bit 30 in the linux drm code is: > > #define BLM_PCH_OVERRIDE_ENABLE (1 << 30) > > The linux dri code doesn't set that for ivybridge - only for broadwell. > > (also, the linux driver has POSTING_READ() which I'm guessing is to > ensure things made it out to the device and have been flushed before > doing another IO operation.) > > I have my (via sysctl) panel backlight control working again. > > > > -adrian >
Thank you guys, the backlight control works again on my laptop with this patch, suggested by Adrian : --- sys/dev/drm2/i915/intel_display.c.orig (revision 277487) +++ sys/dev/drm2/i915/intel_display.c (working copy) @@ -6995,7 +6995,7 @@ */ I915_WRITE(BLC_PWM_CPU_CTL2, PWM_ENABLE); I915_WRITE(BLC_PWM_CPU_CTL, 0); - I915_WRITE(BLC_PWM_PCH_CTL1, PWM_ENABLE | (1<<30)); + I915_WRITE(BLC_PWM_PCH_CTL1, PWM_ENABLE); } void intel_modeset_init_hw(struct drm_device *dev) but the patch by Andrew does not hurts: http://foxkit.us/FreeBSD/i915-uninitialised-var-fix.diff I am running r277871 with both patches applied. Regards, Maurizio _______________________________________________ firstname.lastname@example.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"