Add gpu_fan param and hwmon fan reading

Co-authored-by: Andreas Rachev <andreasratchev@gmail.com>

src/gpu.cpp

@@ -110,6 +110,14 @@ void getAmdGpuInfo(){
 
             gpu_info.powerUsage = value / 1000000;
         }
+
+        if (amdgpu.fan) {
+            rewind(amdgpu.fan);
+            fflush(amdgpu.fan);
+            if (fscanf(amdgpu.fan, "%d" PRId64, &value) != 1)
+                value = 0;
+            gpu_info.fan_speed = value;
+        }
     }
 
     if (amdgpu.vram_total) {

src/gpu.h

@@ -17,6 +17,7 @@ struct amdgpu_files
     FILE *memory_clock;
     FILE *power_usage;
     FILE *gtt_used;
+    FILE *fan;
 };
 
 extern amdgpu_files amdgpu;
@@ -36,6 +37,7 @@ struct gpuInfo{
     bool is_temp_throttled;
     bool is_other_throttled;
     float gtt_used;
+    int fan_speed;
 };
 
 extern struct gpuInfo gpu_info;

src/hud_elements.cpp

@@ -181,6 +181,13 @@ void HudElements::gpu_stats(){
             else
                 ImGui::Text("°C");
         }
+        if (HUDElements.params->enabled[OVERLAY_PARAM_ENABLED_gpu_fan]){
+            right_aligned_text(text_color, HUDElements.ralign_width, "%i", gpu_info.fan_speed);
+            ImGui::SameLine(0, 1.0f);
+            ImGui::PushFont(HUDElements.sw_stats->font1);
+            ImGui::Text("RPM");
+            ImGui::PopFont();
+        }
         if (HUDElements.params->enabled[OVERLAY_PARAM_ENABLED_gpu_core_clock]){
             ImguiNextColumnOrNewRow();
             right_aligned_text(text_color, HUDElements.ralign_width, "%i", gpu_info.CoreClock);

src/overlay.cpp

@@ -794,6 +794,8 @@ void init_gpu_stats(uint32_t& vendorID, uint32_t reported_deviceID, overlay_para
                amdgpu.memory_clock = fopen((hwmon_path + dir + "/freq2_input").c_str(), "r");
             if (!amdgpu.power_usage)
                amdgpu.power_usage = fopen((hwmon_path + dir + "/power1_average").c_str(), "r");
+            if (!amdgpu.fan)
+               amdgpu.fan = fopen((hwmon_path + dir + "/fan1_input").c_str(), "r");
          }
          break;
       }

src/overlay_params.h

@@ -94,6 +94,7 @@ typedef unsigned long KeySym;
    OVERLAY_PARAM_BOOL(trilinear)                     \
    OVERLAY_PARAM_BOOL(bicubic)                       \
    OVERLAY_PARAM_BOOL(retro)                         \
+   OVERLAY_PARAM_BOOL(gpu_fan)                       \
    OVERLAY_PARAM_CUSTOM(fps_sampling_period)         \
    OVERLAY_PARAM_CUSTOM(output_folder)               \
    OVERLAY_PARAM_CUSTOM(output_file)                 \