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From:   Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
To:     Dave Stevenson <dave.stevenson@raspberrypi.com>,
        Andrzej Hajda <andrzej.hajda@intel.com>,
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Cc:     Marek Vasut <marex@denx.de>, dri-devel@lists.freedesktop.org,
        linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org,
        freedreno@lists.freedesktop.org
Subject: [RFC PATCH 02/10] drm/mipi-dsi: document DSI hosts limitations
Date:   Mon, 16 Oct 2023 19:53:47 +0300
Message-ID: <20231016165355.1327217-3-dmitry.baryshkov@linaro.org>
In-Reply-To: <20231016165355.1327217-1-dmitry.baryshkov@linaro.org>
References: <20231016165355.1327217-1-dmitry.baryshkov@linaro.org>
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Document the known limititations of the DSI hosts vs commands transfers
in LP mode. For the details see sun6i_dsi_encoder_enable().

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 include/drm/drm_mipi_dsi.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/include/drm/drm_mipi_dsi.h b/include/drm/drm_mipi_dsi.h
index c9df0407980c..167742e579e3 100644
--- a/include/drm/drm_mipi_dsi.h
+++ b/include/drm/drm_mipi_dsi.h
@@ -85,6 +85,10 @@ int mipi_dsi_create_packet(struct mipi_dsi_packet *packet,
  * host is in. Drivers that need the underlying device to be powered to
  * perform these operations will first need to make sure it's been
  * properly enabled.
+ *
+ * Note: some hosts (sunxi) can not send LP commands between HS video
+ * packets. Thus all DSI transfers sent in LP mode should be limited to the
+ * drm_bridge_funcs::pre_enable() and drm_panel_funcs::prepare() callbacks.
  */
 struct mipi_dsi_host_ops {
 	int (*attach)(struct mipi_dsi_host *host,
-- 
2.42.0