4.15-stable review patch. If anyone has any objections, please let me know.
------------------ From: Rodrigo Vivi <rodrigo.v...@intel.com> commit f24c606c21a8cb6f75adc20edcd80b6d851991bf upstream. Let's ignore VBT request if the pin is clearly wrong. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=104139 Cc: Kai Heng Feng <kai.heng.f...@canonical.com> Signed-off-by: Rodrigo Vivi <rodrigo.v...@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20180123174050.4261-1-rodrigo.v...@intel.com Reviewed-by: Radhakrishna Sripada <radhakrishna.srip...@intel.com> (cherry picked from commit a8e6f3888b05c1e7b685800a3371ce050720368f) Signed-off-by: Rodrigo Vivi <rodrigo.v...@intel.com> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- drivers/gpu/drm/i915/intel_bios.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) --- a/drivers/gpu/drm/i915/intel_bios.c +++ b/drivers/gpu/drm/i915/intel_bios.c @@ -1115,9 +1115,14 @@ static const u8 cnp_ddc_pin_map[] = { static u8 map_ddc_pin(struct drm_i915_private *dev_priv, u8 vbt_pin) { - if (HAS_PCH_CNP(dev_priv) && - vbt_pin > 0 && vbt_pin < ARRAY_SIZE(cnp_ddc_pin_map)) - return cnp_ddc_pin_map[vbt_pin]; + if (HAS_PCH_CNP(dev_priv)) { + if (vbt_pin > 0 && vbt_pin < ARRAY_SIZE(cnp_ddc_pin_map)) + return cnp_ddc_pin_map[vbt_pin]; + if (vbt_pin > GMBUS_PIN_4_CNP) { + DRM_DEBUG_KMS("Ignoring alternate pin: VBT claims DDC pin %d, which is not valid for this platform\n", vbt_pin); + return 0; + } + } return vbt_pin; }
