[PATCH 1/8] net: qualcomm: rmnet: fix struct rmnet_map_header

From: Alex Elder
Date: Mon May 20 2019 - 09:57:15 EST


The C bit-fields in the first byte of the rmnet_map_header structure
are defined in the wrong order. The first byte should be formatted
this way:
+------- reserved_bit
| +----- cd_bit
| |
v v
+-----------+-+-+
| pad_len |R|C|
+-----------+-+-+
7 6 5 4 3 2 1 0 <-- bit position

But the C bit-fields that define the first byte are defined this way:
u8 pad_len:6;
u8 reserved_bit:1;
u8 cd_bit:1;

And although this isn't portable, I can state that when I build it
the result puts the bit-fields in the wrong location (e.g., the
cd_bit is in bit position 7, when it should be position 0).

Fix this by reordering the definitions of these struct members.
Upcoming patches will reimplement these definitions portably.

Signed-off-by: Alex Elder <elder@xxxxxxxxxx>
---
drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h
index 884f1f52dcc2..b1ae9499c0b2 100644
--- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h
+++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_map.h
@@ -40,9 +40,9 @@ enum rmnet_map_commands {
};

struct rmnet_map_header {
- u8 pad_len:6;
- u8 reserved_bit:1;
u8 cd_bit:1;
+ u8 reserved_bit:1;
+ u8 pad_len:6;
u8 mux_id;
__be16 pkt_len;
} __aligned(1);
--
2.20.1