Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlgrafted

Pull pin control updates from Linus Walleij:
 "Core changes:

   - Use the non-blocking mux_state_try_select() in the generic MUX pin
     control back-end

   - Free pin maps on pinctrl_generic_to_map() failure in the core
     helpers

  New hardware pin control:

   - Qualcomm Maili TLMM SoC, PMG1110 PMIC, and Eliza LPASS LPI TLMM SoC
     (this is for the low power audio, LPASS = Low Power Audio SubSystem
     portions)

   - Upboard support on top of the Intel pin controller

   - Apple T6030 and T6031 support (just compatible strings)

   - Samsung Exynos 8855 SoC

   - Mediatek MT6858 SoC

   - Rockchip RK3308B and RV1106 SoCs

   - Airoha EN7523 and AN7563 SoCs

  Improvements:

   - Qualcomm TLMM GPIOs are unconditionally marked as wakeup capable

   - Qualcomm improvements on top of the Qualcomm PDC (power domain
     controller) irqchip improvements from tglx:s tree

   - Qualcomm IPQ806x and IPQ9650 non-urgent pin grop fixups

   - The NPCM8xx driver has been put into shape fixing many pin and
     group definitions

   - Some non-urgent Tegra 264 pin assignments are fixed up

   - Some non-urgent fixups to Airoha AN7581 and AN7583 registers and
     pin assignments, missing features etc"

* tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (130 commits)
  dt-bindings: pinctrl: Convert TI DA850 pupd to DT schema
  pinctrl: meson: sync some modify from A4
  pinctrl: meson: a4: Add input enable pin configuration
  pinctrl: realtek: rtd1625: remove unused group name spdif_sel
  pinctrl: realtek: rtd1625: fix base_bit for VE4 GPIO 13
  dt-bindings: pinctrl: microchip,pic32mzda-pinctrl: Convert to DT schema
  Revert "Merge branch 'ib-rsk7204' into devel"
  pinctrl: rockchip: Add RV1106 pinctrl support
  dt-bindings: pinctrl: rockchip: Add RV1106 compatible
  pinctrl: rockchip: Decode drive strength in the get function
  pinctrl: fix PINCTRL_GENERIC_MUX not always being selectable
  pinctrl: airoha: add support of an7563 SoC
  dt-bindings: pinctrl: airoha: add support of an7563 pin controller
  pinctrl: airoha: try to find chip scu node by phandle first
  pinctrl: airoha: add support of en7523 SoC
  dt-bindings: pinctrl: airoha: add support of en7523 pin controller
  pinctrl: airoha: an7583: add support for olt pinmux
  pinctrl: airoha: an7583: add support for pon_alt pinmux
  pinctrl: airoha: an7583: add support for npu_uart pinmux
  dt-bindings: pinctrl: airoha: an7583: add missed features
  ...

1 files changed, 36 insertions, 0 deletions

diff --git a/Documentation/filesystems/devpts.rst b/Documentation/filesystems/devpts.rst
new file mode 100644
index 000000000..b6324ab19
--- /dev/null
+++ b/Documentation/filesystems/devpts.rst
@@ -0,0 +1,36 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+=====================
+The Devpts Filesystem
+=====================
+
+Each mount of the devpts filesystem is now distinct such that ptys
+and their indices allocated in one mount are independent from ptys
+and their indices in all other mounts.
+
+All mounts of the devpts filesystem now create a ``/dev/pts/ptmx`` node
+with permissions ``0000``.
+
+To retain backwards compatibility the a ptmx device node (aka any node
+created with ``mknod name c 5 2``) when opened will look for an instance
+of devpts under the name ``pts`` in the same directory as the ptmx device
+node.
+
+As an option instead of placing a ``/dev/ptmx`` device node at ``/dev/ptmx``
+it is possible to place a symlink to ``/dev/pts/ptmx`` at ``/dev/ptmx`` or
+to bind mount ``/dev/ptx/ptmx`` to ``/dev/ptmx``.  If you opt for using
+the devpts filesystem in this manner devpts should be mounted with
+the ``ptmxmode=0666``, or ``chmod 0666 /dev/pts/ptmx`` should be called.
+
+Total count of pty pairs in all instances is limited by sysctls::
+
+    kernel.pty.max = 4096	- global limit
+    kernel.pty.reserve = 1024	- reserved for filesystems mounted from the initial mount namespace
+    kernel.pty.nr		- current count of ptys
+
+Per-instance limit could be set by adding mount option ``max=<count>``.
+
+This feature was added in kernel 3.4 together with
+``sysctl kernel.pty.reserve``.
+
+In kernels older than 3.4 sysctl ``kernel.pty.max`` works as per-instance limit.