Openwrt/target/linux/bcm27xx/patches-5.4/950-0613-dt-Drop-I2C-for-Pi4-HDMI-interfaces-to-97.5kHz.patch
Álvaro Fernández Rojas f07e572f64 bcm27xx: import latest patches from the RPi foundation
bcm2708: boot tested on RPi B+ v1.2
bcm2709: boot tested on RPi 3B v1.2 and RPi 4B v1.1 4G
bcm2710: boot tested on RPi 3B v1.2
bcm2711: boot tested on RPi 4B v1.1 4G

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
2021-02-18 23:42:32 +01:00

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1.1 KiB
Diff

From 460ddd2729f0dbb2723e48f3a22ffccbb78b42c7 Mon Sep 17 00:00:00 2001
From: Dave Stevenson <dave.stevenson@raspberrypi.com>
Date: Tue, 31 Mar 2020 17:54:08 +0100
Subject: [PATCH] dt: Drop I2C for Pi4 HDMI interfaces to 97.5kHz.
It was set to 390kHz, which is outside of the required spec for
reading HDMI (max 100kHz). The i2c-brcmstb driver only supports
a number of fixed bus speeds, of which 97.5kHz is the closest to
100kHz without exceeding it.
Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
---
arch/arm/boot/dts/bcm2711.dtsi | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/arch/arm/boot/dts/bcm2711.dtsi
+++ b/arch/arm/boot/dts/bcm2711.dtsi
@@ -358,7 +358,7 @@
compatible = "brcm,bcm2711-hdmi-i2c";
reg = <0x7ef04500 0x100>, <0x7ef00b00 0x300>;
reg-names = "bsc", "auto-i2c";
- clock-frequency = <390000>;
+ clock-frequency = <97500>;
status = "disabled";
};
@@ -395,7 +395,7 @@
compatible = "brcm,bcm2711-hdmi-i2c";
reg = <0x7ef09500 0x100>, <0x7ef05b00 0x300>;
reg-names = "bsc", "auto-i2c";
- clock-frequency = <390000>;
+ clock-frequency = <97500>;
status = "disabled";
};
};