From 9615dee441f72d194234455ed30660c145260973 Mon Sep 17 00:00:00 2001 From: Daniel Vetter Date: Sat, 12 May 2012 20:22:00 +0200 Subject: drm/i915: fixup infoframe support for sdvo MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit commit 81014b9d0b55fb0b48f26cd2a943359750d532db upstream. At least the worst offenders: - SDVO specifies that the encoder should compute the ecc. Testing also shows that we must not send the ecc field, so copy the dip_infoframe struct to a temporay place and avoid the ecc field. This way the avi infoframe is exactly 17 bytes long, which agrees with what the spec mandates as a minimal storage capacity (with the ecc field it would be 18 bytes). - Only 17 when sending the avi infoframe. The SDVO spec explicitly says that sending more data than what the device announces results in undefined behaviour. - Add __attribute__((packed)) to the avi and spd infoframes, for otherwise they're wrongly aligned. Noticed because the avi infoframe ended up being 18 bytes large instead of 17. We haven't noticed this yet because we don't use the uint16_t fields yet (which are the only ones that would be wrongly aligned). This regression has been introduce by 3c17fe4b8f40a112a85758a9ab2aebf772bdd647 is the first bad commit commit 3c17fe4b8f40a112a85758a9ab2aebf772bdd647 Author: David Härdeman Date: Fri Sep 24 21:44:32 2010 +0200 i915: enable AVI infoframe for intel_hdmi.c [v4] Patch tested on my g33 with a sdvo hdmi adaptor. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=25732 Tested-by: Peter Ross (G35 SDVO-HDMI) Reviewed-by: Eugeni Dodonov Signed-Off-by: Daniel Vetter Cc: Ben Hutchings Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/i915/intel_drv.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/gpu/drm/i915/intel_drv.h') diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index 47bf5e1..58b54ff 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -204,7 +204,7 @@ struct dip_infoframe { uint16_t bottom_bar_start; uint16_t left_bar_end; uint16_t right_bar_start; - } avi; + } __attribute__ ((packed)) avi; uint8_t payload[27]; } __attribute__ ((packed)) body; } __attribute__((packed)); -- cgit v1.1