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charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20241031-drm-dp-msm-add-lttpr-transparent-mode-set-v1-1-cafbb9855f40@linaro.org> References: <20241031-drm-dp-msm-add-lttpr-transparent-mode-set-v1-0-cafbb9855f40@linaro.org> In-Reply-To: <20241031-drm-dp-msm-add-lttpr-transparent-mode-set-v1-0-cafbb9855f40@linaro.org> To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Karol Herbst , Lyude Paul , Danilo Krummrich , Jani Nikula , Rodrigo Vivi , Joonas Lahtinen , Tvrtko Ursulin , Rob Clark , Abhinav Kumar , Dmitry Baryshkov , Sean Paul , Marijn Suijten Cc: Bjorn Andersson , Konrad Dybcio , Johan Hovold , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, nouveau@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org, linux-arm-msm@vger.kernel.org, freedreno@lists.freedesktop.org, Abel Vesa X-Mailer: b4 0.15-dev-dedf8 X-Developer-Signature: v=1; a=openpgp-sha256; l=2644; i=abel.vesa@linaro.org; h=from:subject:message-id; bh=XZ/ajUYHZWGgjHmhbqkl1JrHUAEV1/I5zI1XoBp5oT0=; b=owEBbQKS/ZANAwAKARtfRMkAlRVWAcsmYgBnI553SM15YeJbcMDIXDi0Ccw8bC8HLQgGja2a9 zapG9ymj3mJAjMEAAEKAB0WIQRO8+4RTnqPKsqn0bgbX0TJAJUVVgUCZyOedwAKCRAbX0TJAJUV VgxrD/9wtFx1ut1ApWOFw6oQSMKUOJZZ5yLIv7D9H64dDvMeq2yt63ez443XjVQpHqnGfHh82XJ zG4LWKWshUh/2NFkKOO9FdRvHwANmz/OUrBZsdmHWWS64GsjL1pgo8xhoOPrtiNFs7vmekDX8RN +610XpsGno1VZWuH5KE9lU+Obd0wsoo9LEQ/tDx7UgDD0rt7RomUoxHKvz8GeBWPBrFLhYBiy54 ijLYRO13NAyPzpeRL7/79JoPD3fNWaEW2JXcQoa7HIltKcYdlvIJi+72zmLuwaXKIUAwKquH+xJ qKHrrqgCtt0bvHP/X3oquE6qLSEWin3LpoPjO//FL9PVHdgl064nweiJM72soEQxzszlM2REyUR 8P3JtB6oQzddMfWFULERRtJ1w0uNba3MsYdtNSs6dmry55DbRqf/x1YEec0E1MvOicPPJQXdawd R7sffKgETc1ct02DiQ0lHjiyoW/BB/WPKY9jKMQgsPEl6w2Q70ycSHVf7iMNNUHyG9VCu+k3a5M h+F0qIKxaAu6wUnS6hzws9GrJKEktaVEhArNM/xIPW7EsonoSm81JO7CWBDmfnrFKCoes4/9767 WUED81PmXTlMUlgnvYwhmdKTEmN7WjFWxV+yJhO6tLFqjgz+Fw4rk3JOQin+WsBTEN4TnEuJlT4 eOdc/7bpLxb0srg== X-Developer-Key: i=abel.vesa@linaro.org; a=openpgp; fpr=6AFF162D57F4223A8770EF5AF7BF214136F41FAE According to the DisplayPort standard, LTTPRs have two operating modes: - non-transparent - it replies to DPCD LTTPR field specific AUX requests, while passes through all other AUX requests - transparent - it passes through all AUX requests. Switching between this two modes is done by the DPTX by issuing an AUX write to the DPCD PHY_REPEATER_MODE register. Add a generic helper that allows switching between these modes. Signed-off-by: Abel Vesa --- drivers/gpu/drm/display/drm_dp_helper.c | 17 +++++++++++++++++ include/drm/display/drm_dp_helper.h | 1 + 2 files changed, 18 insertions(+) diff --git a/drivers/gpu/drm/display/drm_dp_helper.c b/drivers/gpu/drm/disp= lay/drm_dp_helper.c index 6ee51003de3ce616c3a52653c2f1979ad7658e21..38d612345986ad54b42228902ea= 718a089d169c4 100644 --- a/drivers/gpu/drm/display/drm_dp_helper.c +++ b/drivers/gpu/drm/display/drm_dp_helper.c @@ -2694,6 +2694,23 @@ int drm_dp_lttpr_max_link_rate(const u8 caps[DP_LTTP= R_COMMON_CAP_SIZE]) } EXPORT_SYMBOL(drm_dp_lttpr_max_link_rate); =20 +/** + * drm_dp_lttpr_set_transparent_mode - set the LTTPR in transparent mode + * @aux: DisplayPort AUX channel + * @enable: Enable or disable transparent mode + * + * Returns 0 on success or a negative error code on failure. + */ + +int drm_dp_lttpr_set_transparent_mode(struct drm_dp_aux *aux, bool enable) +{ + u8 val =3D enable ? DP_PHY_REPEATER_MODE_TRANSPARENT : + DP_PHY_REPEATER_MODE_NON_TRANSPARENT; + + return drm_dp_dpcd_writeb(aux, DP_PHY_REPEATER_MODE, val); +} +EXPORT_SYMBOL(drm_dp_lttpr_set_transparent_mode); + /** * drm_dp_lttpr_max_lane_count - get the maximum lane count supported by a= ll LTTPRs * @caps: LTTPR common capabilities diff --git a/include/drm/display/drm_dp_helper.h b/include/drm/display/drm_= dp_helper.h index 279624833ea9259809428162f4e845654359f8c9..8821ab2d36b0e04d38ccbdddcb7= 03b34de7ed680 100644 --- a/include/drm/display/drm_dp_helper.h +++ b/include/drm/display/drm_dp_helper.h @@ -625,6 +625,7 @@ int drm_dp_read_lttpr_phy_caps(struct drm_dp_aux *aux, u8 caps[DP_LTTPR_PHY_CAP_SIZE]); int drm_dp_lttpr_count(const u8 cap[DP_LTTPR_COMMON_CAP_SIZE]); int drm_dp_lttpr_max_link_rate(const u8 caps[DP_LTTPR_COMMON_CAP_SIZE]); +int drm_dp_lttpr_set_transparent_mode(struct drm_dp_aux *aux, bool enable); int drm_dp_lttpr_max_lane_count(const u8 caps[DP_LTTPR_COMMON_CAP_SIZE]); bool drm_dp_lttpr_voltage_swing_level_3_supported(const u8 caps[DP_LTTPR_P= HY_CAP_SIZE]); bool drm_dp_lttpr_pre_emphasis_level_3_supported(const u8 caps[DP_LTTPR_PH= Y_CAP_SIZE]); --=20 2.34.1