From b8437914f0d40dcc0b43b1acad2ca9efcf2b203c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Felix=20=22xq=22=20Quei=C3=9Fner?= <git@random-projects.net>
Date: Sat, 23 Sep 2023 21:26:15 +0200
Subject: [PATCH] Fixes blinky for ESP32-C3-32S-Kit

---
 espressif-esp/README.md      |  4 +++
 espressif-esp/src/blinky.zig | 63 +++++++++++++++++++++++++++---------
 2 files changed, 52 insertions(+), 15 deletions(-)
 create mode 100644 espressif-esp/README.md

diff --git a/espressif-esp/README.md b/espressif-esp/README.md
new file mode 100644
index 0000000..bfa4e43
--- /dev/null
+++ b/espressif-esp/README.md
@@ -0,0 +1,4 @@
+# Examples for the BSP `espressif-esp`
+
+- [Blinky](src/blinky.zig) on [ESP32-C3-32S-Kit](https://www.waveshare.com/wiki/ESP-C3-32S-Kit)  
+  Showcases how to do a simple RGB cycling.
diff --git a/espressif-esp/src/blinky.zig b/espressif-esp/src/blinky.zig
index 811b048..a44ac5f 100644
--- a/espressif-esp/src/blinky.zig
+++ b/espressif-esp/src/blinky.zig
@@ -5,53 +5,86 @@ const TIMG0 = peripherals.TIMG0;
 const RTC_CNTL = peripherals.RTC_CNTL;
 const INTERRUPT_CORE0 = peripherals.INTERRUPT_CORE0;
 const GPIO = peripherals.GPIO;
+const IO_MUX = peripherals.IO_MUX;
 
 const dogfood: u32 = 0x50D83AA1;
 const super_dogfood: u32 = 0x8F1D312A;
 
+const LED_R_PIN = 3; // GPIO
+const LED_G_PIN = 4; // GPIO
+const LED_B_PIN = 5; // GPIO
+
+const led_pins = [_]u32{
+    LED_R_PIN,
+    LED_G_PIN,
+    LED_B_PIN,
+};
+
 pub fn main() !void {
+    // Feed and disable watchdog 0
     TIMG0.WDTWPROTECT.raw = dogfood;
     TIMG0.WDTCONFIG0.raw = 0;
     TIMG0.WDTWPROTECT.raw = 0;
 
+    // Feed and disable rtc watchdog
     RTC_CNTL.WDTWPROTECT.raw = dogfood;
     RTC_CNTL.WDTCONFIG0.raw = 0;
     RTC_CNTL.WDTWPROTECT.raw = 0;
 
+    // Feed and disable rtc super watchdog
     RTC_CNTL.SWD_WPROTECT.raw = super_dogfood;
     RTC_CNTL.SWD_CONF.modify(.{ .SWD_DISABLE = 1 });
     RTC_CNTL.SWD_WPROTECT.raw = 0;
 
+    // Disable all interrupts
     INTERRUPT_CORE0.CPU_INT_ENABLE.raw = 0;
 
-    microzig.hal.gpio.init(LED_R_PIN, .{
-        .direction = .output,
-        .direct_io = true,
-    });
-    microzig.hal.gpio.init(LED_G_PIN, .{
-        .direction = .output,
-        .direct_io = true,
-    });
-    microzig.hal.gpio.init(LED_B_PIN, .{
-        .direction = .output,
-        .direct_io = true,
+    GPIO.ENABLE.modify(.{
+        .DATA = (1 << LED_R_PIN) |
+            (1 << LED_G_PIN) |
+            (1 << LED_B_PIN),
     });
 
+    for (led_pins) |pin| {
+        IO_MUX.GPIO[pin].modify(.{
+            .MCU_OE = 1, // 1: output enabled
+            .SLP_SEL = 0, // Set to 1 to put the pin in sleep mode. (R/W)
+            .MCU_WPD = 0, // 0: internal pull-down disabled. (R/W)
+            .MCU_WPU = 0, // 0: internal pull-up disabled. (R/W)
+            .MCU_IE = 0, // 0: input disabled. (R/W)
+            .FUN_WPD = 0, // 0: internal pull-down disabled. (R/W)
+            .FUN_WPU = 0, // 0: internal pull-up disabled. (R/W)
+            .FUN_IE = 0, // 0: input disabled. (R/W)
+            .FUN_DRV = 3, // Select the drive strength of the pin. 0: ~5 mA; 1: ~ 10 mA; 2: ~ 20 mA; 3: ~40mA. (R/W)
+            .MCU_SEL = 1, // 1: GPIO
+            .FILTER_EN = 0, // 0: Filter disabled. (R/W)
+        });
+
+        GPIO.FUNC_OUT_SEL_CFG[pin].write(.{
+            // If a value 128 is written to this field, bit n of GPIO_OUT_REG and GPIO_ENABLE_REG will be selected as the output value and output enable. (R/W)
+            .OUT_SEL = 0x80,
+
+            .INV_SEL = 0x00, // 0: Do not invert the output value
+            .OEN_SEL = 0x01, // 1: Force the output enable signal to be sourced from bit n of GPIO_ENABLE_REG. (R/W)
+            .OEN_INV_SEL = 0x00, // 0: Do not invert the output enable signal
+
+            .padding = 0,
+        });
+    }
+
     microzig.hal.uart.write(0, "Hello from Zig!\r\n");
 
     while (true) {
         GPIO.OUT.modify(.{ .DATA_ORIG = (1 << LED_R_PIN) });
         microzig.hal.uart.write(0, "R");
         microzig.core.experimental.debug.busy_sleep(100_000);
+
         GPIO.OUT.modify(.{ .DATA_ORIG = (1 << LED_G_PIN) });
         microzig.hal.uart.write(0, "G");
         microzig.core.experimental.debug.busy_sleep(100_000);
+
         GPIO.OUT.modify(.{ .DATA_ORIG = (1 << LED_B_PIN) });
         microzig.hal.uart.write(0, "B");
         microzig.core.experimental.debug.busy_sleep(100_000);
     }
 }
-
-const LED_R_PIN = 3; // GPIO
-const LED_G_PIN = 16; // GPIO
-const LED_B_PIN = 17; // GPIO