Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 49 insertions, 0 deletions

diff --git a/Documentation/driver-api/tty/tty_buffer.rst b/Documentation/driver-api/tty/tty_buffer.rst
new file mode 100644
index 0000000000..4b5ca1776d
--- /dev/null
+++ b/Documentation/driver-api/tty/tty_buffer.rst
@@ -0,0 +1,49 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+==========
+TTY Buffer
+==========
+
+.. contents:: :local:
+
+Here, we document functions for taking care of tty buffer and their flipping.
+Drivers are supposed to fill the buffer by one of those functions below and
+then flip the buffer, so that the data are passed to :doc:`line discipline
+<tty_ldisc>` for further processing.
+
+Flip Buffer Management
+======================
+
+.. kernel-doc:: drivers/tty/tty_buffer.c
+   :identifiers: tty_prepare_flip_string
+           tty_flip_buffer_push tty_ldisc_receive_buf
+
+.. kernel-doc:: include/linux/tty_flip.h
+   :identifiers: tty_insert_flip_string_fixed_flag tty_insert_flip_string_flags
+           tty_insert_flip_char
+
+----
+
+Other Functions
+===============
+
+.. kernel-doc:: drivers/tty/tty_buffer.c
+   :identifiers: tty_buffer_space_avail tty_buffer_set_limit
+
+----
+
+Buffer Locking
+==============
+
+These are used only in special circumstances. Avoid them.
+
+.. kernel-doc:: drivers/tty/tty_buffer.c
+   :identifiers: tty_buffer_lock_exclusive tty_buffer_unlock_exclusive
+
+----
+
+Internal Functions
+==================
+
+.. kernel-doc:: drivers/tty/tty_buffer.c
+   :internal: