fix FSDP2 test case failure on XPU (#3771)

* fix FSDP2 test case failure on XPU

Signed-off-by: YAO Matrix <matrix.yao@intel.com>

* fix style

Signed-off-by: YAO Matrix <matrix.yao@intel.com>

---------

Signed-off-by: YAO Matrix <matrix.yao@intel.com>

Author: yao-matrix

src/accelerate/accelerator.py

@@ -568,25 +568,18 @@ def __init__(
             and self.distributed_type not in (DistributedType.DEEPSPEED, DistributedType.MEGATRON_LM)
         ):
             self.native_amp = True
-            if self.device.type not in (
-                "xpu",
-                "cuda",
-                "npu",
-                "xla",
-                "mlu",
-                "musa",
-                "hpu",
-                "sdaa",
-                "mps",
-            ) or is_torch_xla_available(check_is_tpu=True):
-                raise ValueError(f"fp16 mixed precision requires a GPU or MPS device (not {self.device.type!r}).")
+            supported_device = ("xpu", "cuda", "npu", "xla", "mlu", "musa", "hpu", "sdaa", "mps")
+            if self.device.type not in supported_device or is_torch_xla_available(check_is_tpu=True):
+                raise ValueError(
+                    f"fp16 mixed precision requires a device in {supported_device} (not {self.device.type!r})."
+                )
             if self.device.type == "mps" and not is_torch_version(">=", "2.5.0"):
                 raise ValueError("fp16 mixed precision with MPS device requires a Pytorch >= 2.5.0")
             kwargs = self.scaler_handler.to_kwargs() if self.scaler_handler is not None else {}
 
             # FSDP2 doesn't use ShardedGradScaler, don't want to modify `get_grad_scaler`, rather create a simple utility
             if self.is_fsdp2:
-                self.scaler = get_fsdp2_grad_scaler(**kwargs)
+                self.scaler = get_fsdp2_grad_scaler(device=self.device.type, **kwargs)
             else:
                 self.scaler = get_grad_scaler(self.distributed_type, **kwargs)