openwrt/target/linux/bcm27xx/patches-5.15/950-0664-drm-vc4-dsi-Correct-max-divider-to-255-not-7.patch
Álvaro Fernández Rojas 20ea6adbf1 bcm27xx: add support for linux v5.15
Build system: x86_64
Build-tested: bcm2708, bcm2709, bcm2710, bcm2711
Run-tested: bcm2708/RPiB+, bcm2709/RPi3B, bcm2710/RPi3B, bcm2711/RPi4B

Signed-off-by: Marty Jones <mj8263788@gmail.com>
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
2022-05-17 15:11:22 +02:00

27 lines
969 B
Diff

From 916c79dc5a1df708d6984f5e964eaa3de7e130f2 Mon Sep 17 00:00:00 2001
From: Dave Stevenson <dave.stevenson@raspberrypi.com>
Date: Fri, 22 Oct 2021 16:48:50 +0100
Subject: [PATCH] drm/vc4: dsi: Correct max divider to 255 (not 7)
The integer divider from parent PLL to DSI clock is capable
of going up to /255, not just /7 that the driver was trying.
This allows for slower link frequencies on the DSI bus where
the resolution permits.
Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
---
drivers/gpu/drm/vc4/vc4_dsi.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/gpu/drm/vc4/vc4_dsi.c
+++ b/drivers/gpu/drm/vc4/vc4_dsi.c
@@ -850,7 +850,7 @@ static bool vc4_dsi_encoder_mode_fixup(s
/* Find what divider gets us a faster clock than the requested
* pixel clock.
*/
- for (divider = 1; divider < 7; divider++) {
+ for (divider = 1; divider < 255; divider++) {
if (parent_rate / (divider + 1) < pll_clock)
break;
}