amdgpu: hwmon: check for power1_input

Some GPUs don't support power1_average and only power1_input.
Some GPUs support both. We check if power1_average exists first, then
fallback to power1_input

src/gpu.cpp

@@ -103,6 +103,9 @@ void getAmdGpuInfo(){
             gpu_info.MemClock = value / 1000000;
         }
 
+        // TODO: on some gpus this will use the power1_input instead
+        // this value is instantaneous and should be averaged over time
+        // probably just average everything in this function to be safe
         if (amdgpu.power_usage) {
             rewind(amdgpu.power_usage);
             fflush(amdgpu.power_usage);

src/overlay.cpp

@@ -930,6 +930,8 @@ 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.power_usage)
+                  amdgpu.power_usage = fopen((hwmon_path + dir + "/power1_input").c_str(), "r");
                if (!amdgpu.fan)
                   amdgpu.fan = fopen((hwmon_path + dir + "/fan1_input").c_str(), "r");
             }