Linux ARM-MSM sub-architecture
 help / color / mirror / Atom feed
From: Pengyu Luo <mitltlatltl@gmail.com>
To: Rob Clark <robin.clark@oss.qualcomm.com>,
	Dmitry Baryshkov <lumag@kernel.org>,
	Abhinav Kumar <abhinav.kumar@linux.dev>,
	Jessica Zhang <jesszhan0024@gmail.com>,
	Sean Paul <sean@poorly.run>,
	Marijn Suijten <marijn.suijten@somainline.org>,
	David Airlie <airlied@gmail.com>, Simona Vetter <simona@ffwll.ch>
Cc: Pengyu Luo <mitltlatltl@gmail.com>,
	linux-arm-msm@vger.kernel.org, dri-devel@lists.freedesktop.org,
	freedreno@lists.freedesktop.org, linux-kernel@vger.kernel.org
Subject: [PATCH 2/2] drm/msm/dsi: fix hdisplay calculation for CMD mode panel
Date: Sat,  7 Mar 2026 19:12:49 +0800	[thread overview]
Message-ID: <20260307111250.105772-2-mitltlatltl@gmail.com> (raw)
In-Reply-To: <20260307111250.105772-1-mitltlatltl@gmail.com>

ac47870fd795 incorrecly broke hdisplay calculation for CMD mode, fix
it.

Fixes: ac47870fd795 ("drm/msm/dsi: fix hdisplay calculation when programming dsi registers")
Signed-off-by: Pengyu Luo <mitltlatltl@gmail.com>
---
 drivers/gpu/drm/msm/dsi/dsi_host.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
index 7c16216e8b..f63165c7ce 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_host.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
@@ -1016,8 +1016,9 @@ static void dsi_timing_setup(struct msm_dsi_host *msm_host, bool is_bonded_dsi)
 		/*
 		 * DPU sends 3 bytes per pclk cycle to DSI. If widebus is
 		 * enabled, MDP always sends out 48-bit compressed data per
-		 * pclk and on average, DSI consumes an amount of compressed
-		 * data equivalent to the uncompressed pixel depth per pclk.
+		 * pclk and on average, for video mode, DSI consumes only an
+		 * amount of compressed data equivalent to the uncompressed
+		 * pixel depth per pclk.
 		 *
 		 * Calculate the number of pclks needed to transmit one line of
 		 * the compressed data.
@@ -1029,10 +1030,14 @@ static void dsi_timing_setup(struct msm_dsi_host *msm_host, bool is_bonded_dsi)
 		 * unused anyway.
 		 */
 		h_total -= hdisplay;
-		if (wide_bus_enabled)
-			bits_per_pclk = dsc->bits_per_component * 3;
-		else
+		if (wide_bus_enabled) {
+			if (msm_host->mode_flags & MIPI_DSI_MODE_VIDEO)
+				bits_per_pclk = dsc->bits_per_component * 3;
+			else
+				bits_per_pclk = 48;
+		} else {
 			bits_per_pclk = 24;
+		}
 
 		hdisplay = DIV_ROUND_UP(msm_dsc_get_bytes_per_line(msm_host->dsc) * 8, bits_per_pclk);
 
-- 
2.53.0


  reply	other threads:[~2026-03-07 11:13 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-03-07 11:12 [PATCH 1/2] drm/msm/dsi: fix bits_per_pclk Pengyu Luo
2026-03-07 11:12 ` Pengyu Luo [this message]
2026-03-29 18:04   ` [PATCH 2/2] drm/msm/dsi: fix hdisplay calculation for CMD mode panel Marijn Suijten
2026-03-20  1:48 ` [PATCH 1/2] drm/msm/dsi: fix bits_per_pclk Dmitry Baryshkov
2026-03-20 11:11   ` Pengyu Luo
2026-03-27 19:47 ` Dmitry Baryshkov
2026-04-14 10:13   ` Luca Weiss
2026-04-14 18:11     ` Dmitry Baryshkov

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20260307111250.105772-2-mitltlatltl@gmail.com \
    --to=mitltlatltl@gmail.com \
    --cc=abhinav.kumar@linux.dev \
    --cc=airlied@gmail.com \
    --cc=dri-devel@lists.freedesktop.org \
    --cc=freedreno@lists.freedesktop.org \
    --cc=jesszhan0024@gmail.com \
    --cc=linux-arm-msm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=lumag@kernel.org \
    --cc=marijn.suijten@somainline.org \
    --cc=robin.clark@oss.qualcomm.com \
    --cc=sean@poorly.run \
    --cc=simona@ffwll.ch \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox