From 5a65f3582e011d0de947420b89c13442a2fda5b8 Mon Sep 17 00:00:00 2001 From: Paulo Zanoni Date: Tue, 7 Jan 2014 14:55:53 -0200 Subject: drm/i915: don't set modes for 2 connectors on the same encoder In some cases we have more than 1 connector associated to an encoder (e.g., SDVO, Haswell DP/HDMI) and we can only set a mode for one of these connectors. If we only allowed modesets for connected connectors we would never need this patch, but since we do allow modeset for disconnected connectors we may see user space trying to set modes on the two connectors attached to the same encoder, so we need to forbid that. This problem can be reproduced by running the following intel-gpu-tools test case: ./kms_setmode --run-subtest clone-exclusive-crtc Thanks to Daniel Vetter for providing a version of this patch on pastebin. Credits-to: Daniel Vetter Signed-off-by: Paulo Zanoni Reviewed-by: Damien Lespiau Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_display.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) (limited to 'drivers') diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index c4d3f4391686..507fb19c7591 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -9923,17 +9923,21 @@ intel_modeset_stage_output_state(struct drm_device *dev, /* Check for any encoders that needs to be disabled. */ list_for_each_entry(encoder, &dev->mode_config.encoder_list, base.head) { + int num_connectors = 0; list_for_each_entry(connector, &dev->mode_config.connector_list, base.head) { if (connector->new_encoder == encoder) { WARN_ON(!connector->new_encoder->new_crtc); - - goto next_encoder; + num_connectors++; } } - encoder->new_crtc = NULL; -next_encoder: + + if (num_connectors == 0) + encoder->new_crtc = NULL; + else if (num_connectors > 1) + return -EINVAL; + /* Only now check for crtc changes so we don't miss encoders * that will be disabled. */ if (&encoder->new_crtc->base != encoder->base.crtc) { -- cgit v1.2.3