[PATCH 14/14] net: smc91x: dont't use SMC_outw for fixing up halfword-aligned data

Matthew Leach matthew.leach at arm.com
Fri Oct 11 09:52:20 EDT 2013


From: Will Deacon <will.deacon at arm.com>

SMC_outw invokes an endian-aware I/O accessor, which may change the data
endianness before writing to the device. This is not suitable for data
transfers where the memory buffer is simply a string of bytes that does
not require any byte-swapping.

This patches fixes the smc91x SMC_PUSH_DATA macro so that it uses the
string I/O accessor for outputting the leading or trailing halfwords on
halfword-aligned buffers.

Cc: <netdev at vger.kernel.org>
Cc: Nicolas Pitre <nico at fluxnic.net>
Cc: David S. Miller <davem at davemloft.net>
Signed-off-by: Will Deacon <will.deacon at arm.com>
---
 drivers/net/ethernet/smsc/smc91x.h |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/smsc/smc91x.h b/drivers/net/ethernet/smsc/smc91x.h
index 5730fe2..98eedb9 100644
--- a/drivers/net/ethernet/smsc/smc91x.h
+++ b/drivers/net/ethernet/smsc/smc91x.h
@@ -1124,8 +1124,7 @@ static const char * chip_ids[ 16 ] =  {
 			void __iomem *__ioaddr = ioaddr;		\
 			if (__len >= 2 && (unsigned long)__ptr & 2) {	\
 				__len -= 2;				\
-				SMC_outw(*(u16 *)__ptr, ioaddr,		\
-					DATA_REG(lp));		\
+				SMC_outsw(ioaddr, DATA_REG(lp), __ptr, 1); \
 				__ptr += 2;				\
 			}						\
 			if (SMC_CAN_USE_DATACS && lp->datacs)		\
@@ -1133,8 +1132,7 @@ static const char * chip_ids[ 16 ] =  {
 			SMC_outsl(__ioaddr, DATA_REG(lp), __ptr, __len>>2); \
 			if (__len & 2) {				\
 				__ptr += (__len & ~3);			\
-				SMC_outw(*((u16 *)__ptr), ioaddr,	\
-					 DATA_REG(lp));		\
+				SMC_outsw(ioaddr, DATA_REG(lp), __ptr, 1); \
 			}						\
 		} else if (SMC_16BIT(lp))				\
 			SMC_outsw(ioaddr, DATA_REG(lp), p, (l) >> 1);	\
-- 
1.7.9.5




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