target/linux/bcm27xx/patches-5.4/950-0621-dt-Drop-I2C-for-Pi4-HDMI-interfaces-to-97.5kHz.patch

   1 From 460ddd2729f0dbb2723e48f3a22ffccbb78b42c7 Mon Sep 17 00:00:00 2001
   2 From: Dave Stevenson <dave.stevenson@raspberrypi.com>
   3 Date: Tue, 31 Mar 2020 17:54:08 +0100
   4 Subject: [PATCH] dt: Drop I2C for Pi4 HDMI interfaces to 97.5kHz.
   5
   6 It was set to 390kHz, which is outside of the required spec for
   7 reading HDMI (max 100kHz). The i2c-brcmstb driver only supports
   8 a number of fixed bus speeds, of which 97.5kHz is the closest to
   9 100kHz without exceeding it.
  10
  11 Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
  12 ---
  13  arch/arm/boot/dts/bcm2711.dtsi | 4 ++--
  14  1 file changed, 2 insertions(+), 2 deletions(-)
  15
  16 --- a/arch/arm/boot/dts/bcm2711.dtsi
  17 +++ b/arch/arm/boot/dts/bcm2711.dtsi
  18 @@ -358,7 +358,7 @@
  19                         compatible = "brcm,bcm2711-hdmi-i2c";
  20                         reg = <0x7ef04500 0x100>, <0x7ef00b00 0x300>;
  21                         reg-names = "bsc", "auto-i2c";
  22 -                       clock-frequency = <390000>;
  23 +                       clock-frequency = <97500>;
  24                         status = "disabled";
  25                 };
  26
  27 @@ -395,7 +395,7 @@
  28                         compatible = "brcm,bcm2711-hdmi-i2c";
  29                         reg = <0x7ef09500 0x100>, <0x7ef05b00 0x300>;
  30                         reg-names = "bsc", "auto-i2c";
  31 -                       clock-frequency = <390000>;
  32 +                       clock-frequency = <97500>;
  33                         status = "disabled";
  34                 };
  35         };