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Douglas Anderson e49eabe3e1 pinctrl: qcom: Support OUTPUT_ENABLE; deprecate INPUT_ENABLE
The Qualcomm pinctrl driver has been violating the documented meaning
of PIN_CONFIG_INPUT_ENABLE. That documentation says:

  Note that this does not affect the pin's ability to drive output.

...yet the Qualcomm driver's sole action when asked to "enable input"
on a pin is to disable its output.

The Qualcomm driver's implementation stems from the fact that
"output-disable" is a "new" property from 2017. It was introduced in
commit 425562429d ("pinctrl: generic: Add output-enable
property"). The "input-enable" handling in Qualcomm drivers is from
2015 introduced in commit 407f5e392f ("pinctrl: qcom: handle
input-enable pinconf property").

Let's change the Qualcomm driver to move us in the right direction. As
part of this:
1. We'll now support PIN_CONFIG_OUTPUT_ENABLE
2. We'll still support using PIN_CONFIG_INPUT_ENABLE to disable a
   pin's output (in violation of the docs) with a big comment in the
   code. This is needed because old device trees have "input-enable"
   in them and, in some cases, people might need the old
   behavior. While we could programmatically change all old device
   trees, it doesn't really hurt to keep supporting the old behavior
   and we're _supposed_ to try to be compatible with old device trees
   anyway.

It can also be noted that the PIN_CONFIG_INPUT_ENABLE handling code
seems to have purposefully ignored its argument. That means that old
boards that had _either_ "input-disable" or "input-enable" in them
would have had the effect of disabling a pin's output. While we could
change this behavior, since we're only leaving the
PIN_CONFIG_INPUT_ENABLE there for backward compatibility we might as
well be fully backward compatible.

NOTE: despite the fact that we'll still support
PIN_CONFIG_INPUT_ENABLE for _setting_ config, we take it away from
msm_config_group_get(). This appears to be only used for populating
debugfs and fixing debugfs to "output enabled" where relevant instead
of "input enabled" makes more sense and has more truthiness.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Bjorn Andersson <andersson@kernel.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20230323102605.8.Id740ae6a993f9313b58add6b10f6a92795d510d4@changeid
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2023-03-29 10:46:59 +02:00
Documentation dt-bindings: pinctrl: qcom: Add output-enable 2023-03-29 10:46:53 +02:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
arch cpumask: re-introduce constant-sized cpumask optimizations 2023-03-05 14:30:34 -08:00
block block-6.3-2023-03-03 2023-03-03 10:21:39 -08:00
certs Kbuild updates for v6.3 2023-02-26 11:53:25 -08:00
crypto Networking changes for 6.3. 2023-02-21 18:24:12 -08:00
drivers pinctrl: qcom: Support OUTPUT_ENABLE; deprecate INPUT_ENABLE 2023-03-29 10:46:59 +02:00
fs 17 hotfixes. Eight are for MM and seven are for other parts of the 2023-03-04 13:32:50 -08:00
include cpumask: re-introduce constant-sized cpumask optimizations 2023-03-05 14:30:34 -08:00
init Kbuild updates for v6.3 2023-02-26 11:53:25 -08:00
io_uring io_uring-6.3-2023-03-03 2023-03-03 10:25:29 -08:00
ipc Merge branch 'work.namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2023-02-24 19:20:07 -08:00
kernel A set of updates for the interrupt susbsystem: 2023-03-05 11:19:16 -08:00
lib cpumask: re-introduce constant-sized cpumask optimizations 2023-03-05 14:30:34 -08:00
mm mm: avoid gcc complaint about pointer casting 2023-03-04 14:03:27 -08:00
net nfsd-6.3 fixes: 2023-03-01 11:03:44 -08:00
rust Rust fixes for 6.3-rc1 2023-03-03 14:51:15 -08:00
samples LoongArch changes for v6.3 2023-03-01 09:27:00 -08:00
scripts Remove Intel compiler support 2023-03-05 10:49:37 -08:00
security capability: just use a 'u64' instead of a 'u32[2]' array 2023-03-01 10:01:22 -08:00
sound sound fixes for 6.3-rc1 2023-03-04 10:53:59 -08:00
tools Changes in this cycle were: 2023-03-02 09:45:34 -08:00
usr usr/gen_init_cpio.c: remove unnecessary -1 values from int file 2022-10-03 14:21:44 -07:00
virt KVM/riscv changes for 6.3 2023-02-15 12:33:28 -05:00
.clang-format cpumask: re-introduce constant-sized cpumask optimizations 2023-03-05 14:30:34 -08:00
.cocciconfig
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for *.dtso files 2023-02-26 15:28:23 +09:00
.gitignore .gitignore: ignore *.cover and *.mbx 2023-02-05 18:51:22 +09:00
.mailmap mailmap: map Dikshita Agarwal's old address to his current one 2023-03-02 21:54:24 -08:00
.rustfmt.toml rust: add `.rustfmt.toml` 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS There is no particular theme here - mainly quick hits all over the tree. 2023-02-23 17:55:40 -08:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Adding Christian Brauner as VFS co-maintainer. 2023-03-05 11:11:52 -08:00
Makefile Linux 6.3-rc1 2023-03-05 14:52:03 -08:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.