bas_gigaset: collapse CR/LF at end of AT response

Copy the mechanism from ser_/usb_gigaset to avoid producing
spurious empty responses for CR/LF sequences from the device.
Add a comment in all drivers documenting that behaviour.
Correct an off by one error that might result in a one byte
buffer overflow when receiving an unexpectedly long reply.

Impact: minor bugfix
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/isdn/gigaset/asyncdata.c b/drivers/isdn/gigaset/asyncdata.c
index ccb2a7b7c41d..e913beb63f24 100644
--- a/drivers/isdn/gigaset/asyncdata.c
+++ b/drivers/isdn/gigaset/asyncdata.c
@@ -40,6 +40,8 @@ static inline int muststuff(unsigned char c)
  * Append received bytes to the command response buffer and forward them
  * line by line to the response handler. Exit whenever a mode/state change
  * might have occurred.
+ * Note: Received lines may be terminated by CR, LF, or CR LF, which will be
+ * removed before passing the line to the response handler.
  * Return value:
  *      number of processed bytes
  */