On Mon, Apr 25, 2016 at 06:09:01PM +0000, Konstantin Shkolnyy wrote:
> I was planning to define all these bits in a separate future patch.
> Would you rather prefer the magic numbers defined before fixing the bugs?
Fixing the RTS bug (patch 1), which is the only "real" bug, should be
done before adding defines, and fixing and cleaning up the rest.
> I guess I can do that. Is something like this acceptable?
>
> /* CP210X_GET_FLOW/CP210X_SET_FLOW read/write these 0x10 bytes */
> struct cp210x_flow_ctl {
> u8 SERIAL_DTR_MASK : 2; /* byte 0 */
> u8 : 1;
> u8 SERIAL_CTS_HANDSHAKE : 1;
> u8 SERIAL_DSR_HANDSHAKE : 1;
> u8 SERIAL_DCD_HANDSHAKE : 1;
> u8 SERIAL_DSR_SENSITIVITY : 1;
> u8 : 1;
> u8; /* byte 1 */
> u8; /* byte 2 */
> u8; /* byte 3 */
> u8 SERIAL_AUTO_TRANSMIT : 1; /* byte 4 */
> u8 SERIAL_AUTO_RECEIVE : 1;
> u8 SERIAL_ERROR_CHAR : 1;
> u8 SERIAL_NULL_STRIPPING : 1;
> u8 SERIAL_BREAK_CHAR : 1;
> u8 : 1;
> u8 SERIAL_RTS_MASK : 2;
> u8; /* byte 5 */
> u8; /* byte 6 */
> u8 : 7; /* byte 7 */
> u8 SERIAL_XOFF_CONTINUE : 1;
> __le32 ulXonLimit;
> __le32 ulXoffLimit;
> } __packed;
No, shouldn't rely on the layout of bitfields. Define masks and shifts
as needed and the message structure as
struct cp210x_flow_ctl {
__le32 ulControlHandshake;
__le32 ulFlowReplace;
__le32 ulXonLimit;
__le32 ulXoffLimit;
};
that is, as per AN571.
Thanks,
Johan
