Use fp16 for fp16 control nets.

comfy/sd.py

 import torch
+import contextlib
 
 import sd1_clip
 import sd2_clip
@@ -327,23 +328,36 @@ class VAE:
         return samples
 
 class ControlNet:
-    def __init__(self, control_model):
+    def __init__(self, control_model, device="cuda"):
         self.control_model = control_model
         self.cond_hint_original = None
         self.cond_hint = None
         self.strength = 1.0
+        self.device = device
 
     def get_control(self, x_noisy, t, cond_txt):
+        output_dtype = x_noisy.dtype
         if self.cond_hint is None or x_noisy.shape[2] * 8 != self.cond_hint.shape[2] or x_noisy.shape[3] * 8 != self.cond_hint.shape[3]:
             if self.cond_hint is not None:
                 del self.cond_hint
             self.cond_hint = None
-            self.cond_hint = utils.common_upscale(self.cond_hint_original, x_noisy.shape[3] * 8, x_noisy.shape[2] * 8, 'nearest-exact', "center").to(x_noisy.device)
-            print("set cond_hint", self.cond_hint.shape)
-        control = self.control_model(x=x_noisy, hint=self.cond_hint, timesteps=t, context=cond_txt)
+            self.cond_hint = utils.common_upscale(self.cond_hint_original, x_noisy.shape[3] * 8, x_noisy.shape[2] * 8, 'nearest-exact', "center").to(self.control_model.dtype).to(self.device)
+
+        if self.control_model.dtype == torch.float16:
+            precision_scope = torch.autocast
+        else:
+            precision_scope = contextlib.nullcontext
+
+        with precision_scope(self.device):
+            control = self.control_model(x=x_noisy, hint=self.cond_hint, timesteps=t, context=cond_txt)
+        out = []
+        autocast_enabled = torch.is_autocast_enabled()
         for x in control:
             x *= self.strength
-        return control
+            if x.dtype != output_dtype and not autocast_enabled:
+                x = x.to(output_dtype)
+            out.append(x)
+        return out
 
     def set_cond_hint(self, cond_hint, strength=1.0):
         self.cond_hint_original = cond_hint
@@ -377,6 +391,11 @@ def load_controlnet(ckpt_path):
         return None
 
     context_dim = controlnet_data[key].shape[1]
+
+    use_fp16 = False
+    if controlnet_data[key].dtype == torch.float16:
+        use_fp16 = True
+
     control_model = cldm.ControlNet(image_size=32,
                                     in_channels=4,
                                     hint_channels=3,
@@ -389,7 +408,8 @@ def load_controlnet(ckpt_path):
                                     transformer_depth=1,
                                     context_dim=context_dim,
                                     use_checkpoint=True,
-                                    legacy=False)
+                                    legacy=False,
+                                    use_fp16=use_fp16)
 
     if pth:
         class WeightsLoader(torch.nn.Module):