From edbb6136dc9ff62ae894598de0a1fdc46978d753 Mon Sep 17 00:00:00 2001
From: Jeremy Soller <jeremy@system76.com>
Date: Tue, 28 Jan 2020 15:02:12 -0700
Subject: [PATCH] Add support for LED brightness setting

---
 src/board/system76/galp3-c/acpi.c | 52 ++++++++++++++++++++++++++++++-
 1 file changed, 51 insertions(+), 1 deletion(-)

diff --git a/src/board/system76/galp3-c/acpi.c b/src/board/system76/galp3-c/acpi.c
index e42f6ae..299878c 100644
--- a/src/board/system76/galp3-c/acpi.c
+++ b/src/board/system76/galp3-c/acpi.c
@@ -1,11 +1,34 @@
 #include <board/acpi.h>
 #include <board/battery.h>
+#include <board/dac.h>
+#include <board/gpio.h>
 #include <board/peci.h>
 #include <common/debug.h>
-#include <board/gpio.h>
 
 extern bool lid_wake;
 
+uint8_t fcmd = 0;
+uint8_t fdat = 0;
+uint8_t fbuf[4] = { 0, 0, 0, 0 };
+
+void fcommand(void) {
+    switch (fcmd) {
+        // Keyboard backlight
+        case 0xCA:
+            switch (fdat) {
+                // Set white LED brightness
+                case 0x00:
+                    DACDAT5 = fbuf[0];
+                    break;
+                // Get white LED brightness
+                case 0x01:
+                    fbuf[0] = DACDAT5;
+                    break;
+            }
+            break;
+    }
+}
+
 uint8_t acpi_read(uint8_t addr) {
     uint8_t data = 0;
 
@@ -66,6 +89,13 @@ uint8_t acpi_read(uint8_t addr) {
 
         // Set size of flash (from old firmware)
         ACPI_8 (0xE5, 0x80);
+
+        ACPI_8 (0xF8, fcmd);
+        ACPI_8 (0xF9, fdat);
+        ACPI_8 (0xFA, fbuf[0]);
+        ACPI_8 (0xFB, fbuf[1]);
+        ACPI_8 (0xFC, fbuf[2]);
+        ACPI_8 (0xFD, fbuf[3]);
     }
 
     DEBUG("acpi_read %02X = %02X\n", addr, data);
@@ -86,5 +116,25 @@ void acpi_write(uint8_t addr, uint8_t data) {
         case 0xD9:
             gpio_set(&LED_AIRPLANE_N, !(bool)(data & (1 << 6)));
             break;
+
+        case 0xF8:
+            fcmd = data;
+            fcommand();
+            break;
+        case 0xF9:
+            fdat = data;
+            break;
+        case 0xFA:
+            fbuf[0] = data;
+            break;
+        case 0xFB:
+            fbuf[1] = data;
+            break;
+        case 0xFC:
+            fbuf[2] = data;
+            break;
+        case 0xFD:
+            fbuf[3] = data;
+            break;
     }
 }