diff options
Diffstat (limited to 'target/linux/bcm27xx/patches-5.4/950-0963-overlays-Update-i2c0-overlay-to-disable-the-i2c0mux.patch')
| -rw-r--r-- | target/linux/bcm27xx/patches-5.4/950-0963-overlays-Update-i2c0-overlay-to-disable-the-i2c0mux.patch | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/target/linux/bcm27xx/patches-5.4/950-0963-overlays-Update-i2c0-overlay-to-disable-the-i2c0mux.patch b/target/linux/bcm27xx/patches-5.4/950-0963-overlays-Update-i2c0-overlay-to-disable-the-i2c0mux.patch new file mode 100644 index 0000000000..3ce5e0bbd3 --- /dev/null +++ b/target/linux/bcm27xx/patches-5.4/950-0963-overlays-Update-i2c0-overlay-to-disable-the-i2c0mux.patch @@ -0,0 +1,70 @@ +From 2be1e1c949138b40aac6be1e6f761c69e98dcf66 Mon Sep 17 00:00:00 2001 +From: Dave Stevenson <dave.stevenson@raspberrypi.com> +Date: Thu, 3 Sep 2020 14:59:40 +0100 +Subject: [PATCH] overlays: Update i2c0 overlay to disable the + i2c0mux. + +The i2c0 overlay was assigning pinctrl settings to node i2c0, +which is now the port@0 output of the mux. That leaves a high +chance of it colliding with the port@1 output and not doing +what was intended. + +Set the i2c0 overlay to disable i2c0mux, set the pin-ctrl on +the root i2c controller, and redirect the alias, so overall it +behaves exactly as before. +Combining with dtparam=i2c_vc=on is going to cause conflicts, +so this is noted in the README. + +Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com> +--- + arch/arm/boot/dts/overlays/README | 7 +++++++ + arch/arm/boot/dts/overlays/i2c0-overlay.dts | 15 ++++++++++++++- + 2 files changed, 21 insertions(+), 1 deletion(-) + +--- a/arch/arm/boot/dts/overlays/README ++++ b/arch/arm/boot/dts/overlays/README +@@ -1354,6 +1354,13 @@ Name: i2c0 + Info: Change i2c0 pin usage. Not all pin combinations are usable on all + platforms - platforms other then Compute Modules can only use this + to disable transaction combining. ++ Do NOT use in conjunction with dtparam=i2c_vc=on. From the 5.4 kernel ++ onwards the base DT includes the use of i2c_mux_pinctrl to expose two ++ muxings of BSC0 - GPIOs 0&1, and whichever combination is used for the ++ camera and display connectors. This overlay disables that mux and ++ configures /dev/i2c0 to point at whichever set of pins is requested. ++ dtparam=i2c_vc=on will try and enable the mux, so combining the two ++ will cause conflicts. + Load: dtoverlay=i2c0,<param>=<val> + Params: pins_0_1 Use pins 0 and 1 (default) + pins_28_29 Use pins 28 and 29 +--- a/arch/arm/boot/dts/overlays/i2c0-overlay.dts ++++ b/arch/arm/boot/dts/overlays/i2c0-overlay.dts +@@ -5,7 +5,7 @@ + compatible = "brcm,bcm2835"; + + fragment@0 { +- target = <&i2c0>; ++ target = <&i2c0if>; + __overlay__ { + status = "okay"; + pinctrl-0 = <&i2c0_pins>; +@@ -51,6 +51,19 @@ + }; + }; + ++ fragment@6 { ++ target = <&i2c0mux>; ++ __overlay__ { ++ status = "disabled"; ++ }; ++ }; ++ ++ fragment@7 { ++ target-path = "/aliases"; ++ __overlay__ { ++ i2c0 = "/soc/i2c@7e205000"; ++ }; ++ }; + __overrides__ { + pins_0_1 = <0>,"+1-2-3-4"; + pins_28_29 = <0>,"-1+2-3-4"; |