[PATCH 5.10 51/96] net: dsa: microchip: Fix ksz_read64()

Greg Kroah-Hartman
2021-08-16T13:11:59Z

From: Ben Hutchings <ben.hutchings@mind.be>

[ Upstream commit c34f674c8875235725c3ef86147a627f165d23b4 ]

ksz_read64() currently does some dubious byte-swapping on the two
halves of a 64-bit register, and then only returns the high bits.
Replace this with a straightforward expression.

Fixes: e66f840c08a2 ("net: dsa: ksz: Add Microchip KSZ8795 DSA driver")
Signed-off-by: Ben Hutchings <ben.hutchings@mind.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/dsa/microchip/ksz_common.h | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/net/dsa/microchip/ksz_common.h b/drivers/net/dsa/microchip/ksz_common.h
index cf866e48ff66..a51c716ec920 100644
--- a/drivers/net/dsa/microchip/ksz_common.h
+++ b/drivers/net/dsa/microchip/ksz_common.h
@@ -210,12 +210,8 @@ static inline int ksz_read64(struct ksz_device *dev, u32 reg, u64 *val)
int ret;

ret = regmap_bulk_read(dev->regmap[2], reg, value, 2);
- if (!ret) {
- /* Ick! ToDo: Add 64bit R/W to regmap on 32bit systems */
- value[0] = swab32(value[0]);
- value[1] = swab32(value[1]);
- *val = swab64((u64)*value);
- }
+ if (!ret)
+ *val = (u64)value[0] << 32 | value[1];

return ret;
}
--
2.30.2