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 _______________________________________________ freebsd-current@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
