tty: Always handle NULL flag ptr
Most line disciplines already handle the undocumented NULL flag
ptr in their .receive_buf method; however, several don't.
Document the NULL flag ptr, and correct handling in the
N_MOUSE, N_GSM0710 and N_R394 line disciplines.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/include/linux/tty_ldisc.h b/include/linux/tty_ldisc.h
index f15c898..b8347c20 100644
--- a/include/linux/tty_ldisc.h
+++ b/include/linux/tty_ldisc.h
@@ -84,7 +84,8 @@
* processing. <cp> is a pointer to the buffer of input
* character received by the device. <fp> is a pointer to a
* pointer of flag bytes which indicate whether a character was
- * received with a parity error, etc.
+ * received with a parity error, etc. <fp> may be NULL to indicate
+ * all data received is TTY_NORMAL.
*
* void (*write_wakeup)(struct tty_struct *);
*
@@ -118,7 +119,8 @@
* processing. <cp> is a pointer to the buffer of input
* character received by the device. <fp> is a pointer to a
* pointer of flag bytes which indicate whether a character was
- * received with a parity error, etc.
+ * received with a parity error, etc. <fp> may be NULL to indicate
+ * all data received is TTY_NORMAL.
* If assigned, prefer this function for automatic flow control.
*/