allow ACPI to set fan speeds

Smooth ACPI fan pwm values same as EC fan curve points

Author: curiousercreative

src/board/system76/common/acpi.c

@@ -3,6 +3,7 @@
 #include <board/acpi.h>
 #include <board/battery.h>
 #include <board/dgpu.h>
+#include <board/fan.h>
 #include <board/gpio.h>
 #include <board/kbled.h>
 #include <board/lid.h>
@@ -224,5 +225,13 @@ void acpi_write(uint8_t addr, uint8_t data) {
         case 0xFD:
             fbuf[3] = data;
             break;
+        case 0xCE:
+            acpi_peci_fan_duty = data;
+            break;
+#if HAVE_DGPU
+        case 0xCF:
+            acpi_dgpu_fan_duty = data;
+            break;
+#endif
     }
 }

src/board/system76/common/fan.c

@@ -15,6 +15,8 @@
 #define MIN_SPEED_TO_SMOOTH PWM_DUTY(SMOOTH_FANS_MIN)
 
 bool fan_max = false;
+uint8_t acpi_peci_fan_duty = 0;
+uint8_t acpi_dgpu_fan_duty = 0;
 uint8_t last_duty_dgpu = 0;
 uint8_t last_duty_peci = 0;
 
@@ -66,16 +68,23 @@ void fan_duty_set(uint8_t peci_fan_duty, uint8_t dgpu_fan_duty) __reentrant {
         dgpu_fan_duty = peci_fan_duty > dgpu_fan_duty ? peci_fan_duty : dgpu_fan_duty;
     #endif
 
+    // allow for ACPI to request a higher duty
+    peci_fan_duty = peci_fan_duty > acpi_peci_fan_duty ? peci_fan_duty : acpi_peci_fan_duty;
+    dgpu_fan_duty = dgpu_fan_duty > acpi_dgpu_fan_duty ? dgpu_fan_duty : acpi_dgpu_fan_duty;
+
     // set PECI fan duty
     if (peci_fan_duty != DCR2) {
+        TRACE("PECI acpi_fan_duty_raw=%d\n", acpi_peci_fan_duty);
         TRACE("PECI fan_duty_raw=%d\n", peci_fan_duty);
+        // allow for ACPI to request a higher duty
         last_duty_peci = peci_fan_duty = fan_smooth(last_duty_peci, peci_fan_duty);
         DCR2 = fan_max ? MAX_FAN_SPEED : peci_fan_duty;
         TRACE("PECI fan_duty_smoothed=%d\n", peci_fan_duty);
     }
 
     // set dGPU fan duty
     if (dgpu_fan_duty != DCR4) {
+        TRACE("DGPU acpi_fan_duty_raw=%d\n", acpi_peci_fan_duty);
         TRACE("DGPU fan_duty_raw=%d\n", dgpu_fan_duty);
         last_duty_dgpu = dgpu_fan_duty = fan_smooth(last_duty_dgpu, dgpu_fan_duty);
         DCR4 = fan_max ? MAX_FAN_SPEED : dgpu_fan_duty;

src/board/system76/common/include/board/fan.h

@@ -46,6 +46,8 @@ struct Fan {
     bool interpolate;
 };
 
+extern uint8_t acpi_dgpu_fan_duty;
+extern uint8_t acpi_peci_fan_duty;
 extern bool fan_max;
 
 void fan_reset(void);