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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Proofpoint-Spam-Info: AW1haW4tMjYwOTA4MDA5NCBTYWx0ZWRfX3vuiPSlT7vXr 90lR8XN8lSyydh9+vZ3LhJ20yO1BiKE2HldZ6/zxlurKImgSSZd39HJZ43VRcb6YXZssX6+bh7V +gF76Es0FXLzQsTa3YzBrEKmWDz08ts= X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwOTA4MDA5NCBTYWx0ZWRfX8lUe79Jls/Ub 27jvtjJP5784/3anm7r07HIqAwk1nX8pnxePiMGM0AyPuLcDq/2cBHNWarSCRiBsU60gqzNdWdh 9ZNAKv7dh1Iwd/XIr5bsyKhLtXCozVy0o3tWNYm6SUu/VYoh5i2tE24CBtMs1k2M6Sx4xxclQhD zxevq/8/Kz4ShP2STyzcNCyVj3DKNauYjH/RcMcf8eWrrWuE0ShtY6wg8YHSsPiWL1jT1eIMMvA Cv8AitnzLrZk94EFiycs5/AhAGPYhjF8HuTlDtguXPQLyIfphw88aGSD9x3CIW2KKWLpfEkVSBo 34sCa5GN5RObaLNEtCI5qQ3Xsfo89Lr7g9Lvt+nkS0R3PC1RmB6ViKYIV1bKse2Kx7NCE1zrvlf ggSKaxndvsLo6pV8b7UNGzn+eSHbj4skmVgh6QKWg5zUJeZRTkheDIR4uzFowP3hAneLnaBYg/q NI1rwjMiEZ9BOYxx3Zg== X-Proofpoint-ORIG-GUID: H5OvYIQ2aiwKTLTjOWTbNB7_lE3PqCIY X-Authority-Analysis: v=2.4 cv=QrduG1yd c=1 sm=1 tr=0 ts=6a9fcf91 cx=c_pps a=HLyN3IcIa5EE8TELMZ618Q==:117 a=PRfkaYvzSr8QmIIGAkY2Sg==:17 a=IkcTkHD0fZMA:10 a=VdqzKS8jKosA:10 a=s4-Qcg_JpJYA:10 a=VkNPw1HP01LnGYTKEx00:22 a=u7WPNUs3qKkmUXheDGA7:22 a=YMgV9FUhrdKAYTUUvYB2:22 a=VwQbUJbxAAAA:8 a=pGLkceISAAAA:8 a=tHtyKFz_FhAUe0nsBNoA:9 a=QEXdDO2ut3YA:10 a=bTQJ7kPSJx9SKPbeHEYW:22 X-Proofpoint-GUID: H5OvYIQ2aiwKTLTjOWTbNB7_lE3PqCIY X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1176,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-09-08_01,2026-09-07_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 bulkscore=0 adultscore=0 malwarescore=0 lowpriorityscore=0 impostorscore=0 spamscore=0 priorityscore=1501 phishscore=0 suspectscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2609080094 On 9/8/26 11:01 AM, 092vk wrote: > msm_dp_display_prepare_link(), msm_dp_display_disable(), and > msm_dp_hpd_unplug_handle() all treat dp->link->sink_count == 0 as > "nothing is connected", and in msm_dp_display_prepare_link() this > causes probe/enable to fail outright with -ENOTCONN. > > This is correct for external DisplayPort, where a compliant sink is > required to report a valid DP_SINK_COUNT over the AUX channel. It is > not correct for eDP: some eDP sinks -- particularly fixed-format > eDP-to-HDMI bridge chips with no downstream AUX-capable panel > behind them -- never populate DP_SINK_COUNT with a nonzero value, > even while otherwise participating normally in DPCD capability > exchange and link training. > > drm_dp_read_sink_count_cap() already accounts for this by excluding > eDP connectors from the sink-count requirement for other DPCD-derived > checks (msm_dp_bridge_detect() takes care). Apply the same exemption > to the raw sink_count reads in this file via a small shared > helper, so eDP outputs with a non-AUX-capable downstream sink are > not treated as permanently disconnected. > > Tested on a Qualcomm QCS6490-based board driving a fixed-format > eDP-to-HDMI bridge IC (chrontel,ch7218a) with no negotiable > DPCD-capable panel behind it; without this fix, > msm_dp_display_prepare_link() unconditionally returns -ENOTCONN > and the display never comes up. > > Fixes: ca16db3d18cf ("drm/msm/dp: break up dp_display_enable into two parts") > > Signed-off-by: 092vk > --- Hi, please use a known identity https://docs.kernel.org/process/submitting-patches.html#sign-your-work-the-developer-s-certificate-of-origin Konrad