[PATCH AUTOSEL 5.3 69/99] net: aquantia: temperature retrieval fix

From: Sasha Levin
Date: Sat Oct 26 2019 - 09:33:16 EST


From: Igor Russkikh <Igor.Russkikh@xxxxxxxxxxxx>

[ Upstream commit 06b0d7fe7e5ff3ba4c7e265ef41135e8bcc232bb ]

Chip temperature is a two byte word, colocated internally with cable
length data. We do all readouts from HW memory by dwords, thus
we should clear extra high bytes, otherwise temperature output
gets weird as soon as we attach a cable to the NIC.

Fixes: 8f8940118654 ("net: aquantia: add infrastructure to readout chip temperature")
Tested-by: Holger HoffstÃtte <holger@xxxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Igor Russkikh <igor.russkikh@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
.../net/ethernet/aquantia/atlantic/hw_atl/hw_atl_utils_fw2x.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_utils_fw2x.c b/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_utils_fw2x.c
index da726489e3c8d..7bc51f8d6f2fc 100644
--- a/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_utils_fw2x.c
+++ b/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_utils_fw2x.c
@@ -337,7 +337,7 @@ static int aq_fw2x_get_phy_temp(struct aq_hw_s *self, int *temp)
/* Convert PHY temperature from 1/256 degree Celsius
* to 1/1000 degree Celsius.
*/
- *temp = temp_res * 1000 / 256;
+ *temp = (temp_res & 0xFFFF) * 1000 / 256;

return 0;
}
--
2.20.1