From 1bc731fde4af337134331572889de8dd8dbff897 Mon Sep 17 00:00:00 2001
From: "M. Ian Graham" <games@miangraham.com>
Date: Sat, 11 Dec 2021 00:51:56 +0900
Subject: [PATCH 1/4] rpi4: Add option to turn on the ARM I2C bus (i2c1).

---
 raspberry-pi/4/default.nix |  1 +
 raspberry-pi/4/i2c1.nix    | 44 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 45 insertions(+)
 create mode 100644 raspberry-pi/4/i2c1.nix

diff --git a/raspberry-pi/4/default.nix b/raspberry-pi/4/default.nix
index 2fe97e1..d94a9f9 100644
--- a/raspberry-pi/4/default.nix
+++ b/raspberry-pi/4/default.nix
@@ -4,6 +4,7 @@
   imports = [
     ./audio.nix
     ./dwc2.nix
+    ./i2c1.nix
     ./modesetting.nix
     ./poe-hat.nix
     ./tc358743.nix
diff --git a/raspberry-pi/4/i2c1.nix b/raspberry-pi/4/i2c1.nix
new file mode 100644
index 0000000..a93acb3
--- /dev/null
+++ b/raspberry-pi/4/i2c1.nix
@@ -0,0 +1,44 @@
+{ config, lib, pkgs, ... }:
+
+let
+  cfg = config.hardware.raspberry-pi."4".i2c1;
+in
+{
+  options.hardware = {
+    raspberry-pi."4".i2c1 = {
+      enable = lib.mkEnableOption ''
+        Turn on the ARM I2C bus (/dev/i2c-1 on GPIO pins 3 and 5) and enable access from the i2c group.
+        After a reboot, i2c-tools (e.g. i2cdetect -F 1) should work for root or any user in i2c.
+      '';
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    hardware = {
+      i2c.enable = true;
+      deviceTree = {
+        overlays = [
+          # Equivalent to dtparam=i2c1=on
+          {
+            name = "i2c1-on-overlay";
+            dtsText = ''
+            /dts-v1/;
+            /plugin/;
+            / {
+              compatible = "brcm,bcm2711";
+              fragment@0 {
+                target = <&i2c1>;
+                __overlay__ {
+                  #address-cells = <1>;
+                  #size-cells = <0>;
+                  status = "okay";
+                };
+              };
+            };
+          '';
+          }
+        ];
+      };
+    };
+  };
+}

From e81c9aed162c49b6652c18b85b2fed131a1968c2 Mon Sep 17 00:00:00 2001
From: "M. Ian Graham" <games@miangraham.com>
Date: Sat, 11 Dec 2021 05:08:24 +0900
Subject: [PATCH 2/4] raspberry-pi/4/i2c1: indentation fix

---
 raspberry-pi/4/i2c1.nix | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/raspberry-pi/4/i2c1.nix b/raspberry-pi/4/i2c1.nix
index a93acb3..27db73e 100644
--- a/raspberry-pi/4/i2c1.nix
+++ b/raspberry-pi/4/i2c1.nix
@@ -22,20 +22,20 @@ in
           {
             name = "i2c1-on-overlay";
             dtsText = ''
-            /dts-v1/;
-            /plugin/;
-            / {
-              compatible = "brcm,bcm2711";
-              fragment@0 {
-                target = <&i2c1>;
-                __overlay__ {
-                  #address-cells = <1>;
-                  #size-cells = <0>;
-                  status = "okay";
+              /dts-v1/;
+              /plugin/;
+              / {
+                compatible = "brcm,bcm2711";
+                fragment@0 {
+                  target = <&i2c1>;
+                  __overlay__ {
+                    #address-cells = <1>;
+                    #size-cells = <0>;
+                    status = "okay";
+                  };
                 };
               };
-            };
-          '';
+            '';
           }
         ];
       };

From 41c4e294f441f2aa655f7d8985623ec07a4314af Mon Sep 17 00:00:00 2001
From: "M. Ian Graham" <games@miangraham.com>
Date: Sat, 11 Dec 2021 08:34:25 +0900
Subject: [PATCH 3/4] raspberry-pi/4/i2c1: factor out easy dts into helper, add
 i2c0

---
 raspberry-pi/4/default.nix |  1 +
 raspberry-pi/4/i2c0.nix    | 25 +++++++++++++++++++++++++
 raspberry-pi/4/i2c1.nix    | 25 +++----------------------
 raspberry-pi/4/overlay.nix | 18 ++++++++++++++++++
 4 files changed, 47 insertions(+), 22 deletions(-)
 create mode 100644 raspberry-pi/4/i2c0.nix
 create mode 100644 raspberry-pi/4/overlay.nix

diff --git a/raspberry-pi/4/default.nix b/raspberry-pi/4/default.nix
index d94a9f9..7d1bce4 100644
--- a/raspberry-pi/4/default.nix
+++ b/raspberry-pi/4/default.nix
@@ -4,6 +4,7 @@
   imports = [
     ./audio.nix
     ./dwc2.nix
+    ./i2c0.nix
     ./i2c1.nix
     ./modesetting.nix
     ./poe-hat.nix
diff --git a/raspberry-pi/4/i2c0.nix b/raspberry-pi/4/i2c0.nix
new file mode 100644
index 0000000..e4fa779
--- /dev/null
+++ b/raspberry-pi/4/i2c0.nix
@@ -0,0 +1,25 @@
+{ config, lib, pkgs, ... }:
+
+let
+  cfg = config.hardware.raspberry-pi."4".i2c0;
+  inherit (import ./overlay.nix) simple-pi4-overlay;
+in
+{
+  options.hardware = {
+    raspberry-pi."4".i2c0 = {
+      enable = lib.mkEnableOption ''
+        Turn on the VideoCore I2C bus (maps to /dev/i2c-22) and enable access from the i2c group.
+        After a reboot, i2c-tools (e.g. i2cdetect -F 22) should work for root or any user in i2c.
+       '';
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    hardware = {
+      i2c.enable = lib.mkDefault true;
+      deviceTree = {
+        overlays = [ (simple-pi4-overlay { target = "i2c0if"; status = "okay"; }) ];
+      };
+    };
+  };
+}
diff --git a/raspberry-pi/4/i2c1.nix b/raspberry-pi/4/i2c1.nix
index 27db73e..02d2623 100644
--- a/raspberry-pi/4/i2c1.nix
+++ b/raspberry-pi/4/i2c1.nix
@@ -2,6 +2,7 @@
 
 let
   cfg = config.hardware.raspberry-pi."4".i2c1;
+  inherit (import ./overlay.nix) simple-pi4-overlay;
 in
 {
   options.hardware = {
@@ -15,29 +16,9 @@ in
 
   config = lib.mkIf cfg.enable {
     hardware = {
-      i2c.enable = true;
+      i2c.enable = lib.mkDefault true;
       deviceTree = {
-        overlays = [
-          # Equivalent to dtparam=i2c1=on
-          {
-            name = "i2c1-on-overlay";
-            dtsText = ''
-              /dts-v1/;
-              /plugin/;
-              / {
-                compatible = "brcm,bcm2711";
-                fragment@0 {
-                  target = <&i2c1>;
-                  __overlay__ {
-                    #address-cells = <1>;
-                    #size-cells = <0>;
-                    status = "okay";
-                  };
-                };
-              };
-            '';
-          }
-        ];
+        overlays = [ (simple-pi4-overlay { target = "i2c1"; status = "okay"; }) ];
       };
     };
   };
diff --git a/raspberry-pi/4/overlay.nix b/raspberry-pi/4/overlay.nix
new file mode 100644
index 0000000..d32e75f
--- /dev/null
+++ b/raspberry-pi/4/overlay.nix
@@ -0,0 +1,18 @@
+{
+  simple-pi4-overlay = { target, status }: {
+    name = "${target}-${status}-overlay";
+    dtsText = ''
+      /dts-v1/;
+      /plugin/;
+      / {
+        compatible = "brcm,bcm2711";
+        fragment@0 {
+          target = <&${target}>;
+          __overlay__ {
+            status = "${status}";
+          };
+        };
+      };
+    '';
+  };
+}

From 8f1bf828d8606fe38a02df312cf14546ae200a72 Mon Sep 17 00:00:00 2001
From: "M. Ian Graham" <games@miangraham.com>
Date: Sat, 11 Dec 2021 10:26:21 +0900
Subject: [PATCH 4/4] raspberry-pi/4/i2c: refactor i2c stuff into single file

---
 raspberry-pi/4/default.nix |  3 +--
 raspberry-pi/4/i2c.nix     | 47 ++++++++++++++++++++++++++++++++++++++
 raspberry-pi/4/i2c0.nix    | 25 --------------------
 raspberry-pi/4/i2c1.nix    | 25 --------------------
 raspberry-pi/4/overlay.nix | 18 ---------------
 5 files changed, 48 insertions(+), 70 deletions(-)
 create mode 100644 raspberry-pi/4/i2c.nix
 delete mode 100644 raspberry-pi/4/i2c0.nix
 delete mode 100644 raspberry-pi/4/i2c1.nix
 delete mode 100644 raspberry-pi/4/overlay.nix

diff --git a/raspberry-pi/4/default.nix b/raspberry-pi/4/default.nix
index 7d1bce4..fac4cc1 100644
--- a/raspberry-pi/4/default.nix
+++ b/raspberry-pi/4/default.nix
@@ -4,8 +4,7 @@
   imports = [
     ./audio.nix
     ./dwc2.nix
-    ./i2c0.nix
-    ./i2c1.nix
+    ./i2c.nix
     ./modesetting.nix
     ./poe-hat.nix
     ./tc358743.nix
diff --git a/raspberry-pi/4/i2c.nix b/raspberry-pi/4/i2c.nix
new file mode 100644
index 0000000..93c1c6d
--- /dev/null
+++ b/raspberry-pi/4/i2c.nix
@@ -0,0 +1,47 @@
+{ config, lib, pkgs, ... }:
+
+let
+  cfg = config.hardware.raspberry-pi."4";
+  simple-overlay = { target, status }: {
+    name = "${target}-${status}-overlay";
+    dtsText = ''
+      /dts-v1/;
+      /plugin/;
+      / {
+        compatible = "brcm,bcm2711";
+        fragment@0 {
+          target = <&${target}>;
+          __overlay__ {
+            status = "${status}";
+          };
+        };
+      };
+    '';
+  };
+in
+{
+  options.hardware.raspberry-pi."4" = {
+    i2c0.enable = lib.mkEnableOption ''
+      Turn on the VideoCore I2C bus (maps to /dev/i2c-22) and enable access from the i2c group.
+      After a reboot, i2c-tools (e.g. i2cdetect -F 22) should work for root or any user in i2c.
+    '';
+    i2c1.enable = lib.mkEnableOption ''
+      Turn on the ARM I2C bus (/dev/i2c-1 on GPIO pins 3 and 5) and enable access from the i2c group.
+      After a reboot, i2c-tools (e.g. i2cdetect -F 1) should work for root or any user in i2c.
+    '';
+  };
+  config.hardware = lib.mkMerge [
+    (lib.mkIf cfg.i2c0.enable {
+      i2c.enable = lib.mkDefault true;
+      deviceTree = {
+        overlays = [ (simple-overlay { target = "i2c0if"; status = "okay"; }) ];
+      };
+    })
+    (lib.mkIf cfg.i2c1.enable {
+      i2c.enable = lib.mkDefault true;
+      deviceTree = {
+        overlays = [ (simple-overlay { target = "i2c1"; status = "okay"; }) ];
+      };
+    })
+  ];
+}
diff --git a/raspberry-pi/4/i2c0.nix b/raspberry-pi/4/i2c0.nix
deleted file mode 100644
index e4fa779..0000000
--- a/raspberry-pi/4/i2c0.nix
+++ /dev/null
@@ -1,25 +0,0 @@
-{ config, lib, pkgs, ... }:
-
-let
-  cfg = config.hardware.raspberry-pi."4".i2c0;
-  inherit (import ./overlay.nix) simple-pi4-overlay;
-in
-{
-  options.hardware = {
-    raspberry-pi."4".i2c0 = {
-      enable = lib.mkEnableOption ''
-        Turn on the VideoCore I2C bus (maps to /dev/i2c-22) and enable access from the i2c group.
-        After a reboot, i2c-tools (e.g. i2cdetect -F 22) should work for root or any user in i2c.
-       '';
-    };
-  };
-
-  config = lib.mkIf cfg.enable {
-    hardware = {
-      i2c.enable = lib.mkDefault true;
-      deviceTree = {
-        overlays = [ (simple-pi4-overlay { target = "i2c0if"; status = "okay"; }) ];
-      };
-    };
-  };
-}
diff --git a/raspberry-pi/4/i2c1.nix b/raspberry-pi/4/i2c1.nix
deleted file mode 100644
index 02d2623..0000000
--- a/raspberry-pi/4/i2c1.nix
+++ /dev/null
@@ -1,25 +0,0 @@
-{ config, lib, pkgs, ... }:
-
-let
-  cfg = config.hardware.raspberry-pi."4".i2c1;
-  inherit (import ./overlay.nix) simple-pi4-overlay;
-in
-{
-  options.hardware = {
-    raspberry-pi."4".i2c1 = {
-      enable = lib.mkEnableOption ''
-        Turn on the ARM I2C bus (/dev/i2c-1 on GPIO pins 3 and 5) and enable access from the i2c group.
-        After a reboot, i2c-tools (e.g. i2cdetect -F 1) should work for root or any user in i2c.
-      '';
-    };
-  };
-
-  config = lib.mkIf cfg.enable {
-    hardware = {
-      i2c.enable = lib.mkDefault true;
-      deviceTree = {
-        overlays = [ (simple-pi4-overlay { target = "i2c1"; status = "okay"; }) ];
-      };
-    };
-  };
-}
diff --git a/raspberry-pi/4/overlay.nix b/raspberry-pi/4/overlay.nix
deleted file mode 100644
index d32e75f..0000000
--- a/raspberry-pi/4/overlay.nix
+++ /dev/null
@@ -1,18 +0,0 @@
-{
-  simple-pi4-overlay = { target, status }: {
-    name = "${target}-${status}-overlay";
-    dtsText = ''
-      /dts-v1/;
-      /plugin/;
-      / {
-        compatible = "brcm,bcm2711";
-        fragment@0 {
-          target = <&${target}>;
-          __overlay__ {
-            status = "${status}";
-          };
-        };
-      };
-    '';
-  };
-}