From 85a624403c77c3f074931aefdfced59f61b668cb Mon Sep 17 00:00:00 2001
From: Jesse Brandeburg <jesse.brandeburg@intel.com>
Date: Thu, 13 Oct 2016 16:13:55 -0700
Subject: [PATCH] ethtool: silence warning on bit loss

Sparse was complaining when we went to prototype some code
using ethtool_cmd_speed_set and SPEED_100000, which uses
the upper 16 bits of __u32 speed for the first time.

CHECK
...
.../uapi/linux/ethtool.h:123:28: warning:
  cast truncates bits from constant value (186a0 becomes 86a0)

The warning is actually bogus, as no bits are really lost, but
we can get rid of the sparse warning with this one small change.

Reported-by: Preethi Banala <preethi.banala@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 include/uapi/linux/ethtool.h | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h
index 099a4200732c..8e547231c1b7 100644
--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -119,8 +119,7 @@ struct ethtool_cmd {
 static inline void ethtool_cmd_speed_set(struct ethtool_cmd *ep,
 					 __u32 speed)
 {
-
-	ep->speed = (__u16)speed;
+	ep->speed = (__u16)(speed & 0xFFFF);
 	ep->speed_hi = (__u16)(speed >> 16);
 }
 
-- 
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