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charset="us-ascii"; Format="flowed" Sender: "linux-phy" Errors-To: linux-phy-bounces+linux-phy=archiver.kernel.org@lists.infradead.org On 24-08-2026 18:45, Konrad Dybcio wrote: > On 8/24/26 1:28 PM, Saurabh Anand wrote: >> drm_dp_lttpr_count() returns 0 when no LTTPRs are detected and a >> negative value on error. The previous code passed the result directly >> to drm_dp_lttpr_init() without checking, which would call into the >> LTTPR transparency-mode setup with a zero or negative repeater count. >> >> Add an early return for lttpr_count <= 0 to skip the init entirely >> when there are no repeaters in the link, matching the expected usage >> of drm_dp_lttpr_init(). > Reading the body of that function, I'm not sure your statement is true drm_dp_lttpr_count() returns 0 when no LTTPRs are detected and a negative error code when the LTTPR common capabilities report an invalid or unsupported repeater count. drm_dp_lttpr_init() already handles the zero-count case by returning early. However, when passed a negative count, it still writes transparent mode before returning -ENODEV. I will update the commit message giving more details. > > Konrad -- linux-phy mailing list linux-phy@lists.infradead.org https://lists.infradead.org/mailman/listinfo/linux-phy