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Jonas Jelonek 059374aa0a i2c: rtl9300: separate xfer configuration and execution
So far, the rtl9300_i2c_smbus_xfer code is quite a mess with function
calls distributed over the whole function setting different values in
different cases. Calls to rtl9300_i2c_config_xfer and
rtl9300_i2c_reg_addr_set are used in every case-block with varying
values whose meaning is not instantly obvious. In some cases, there are
additional calls within these case-blocks doing more things.

This is in general a bad design and especially really bad for
readability and maintainability because it distributes changes or
issues to multiple locations due to the same function being called with
different hardcoded values in different places.

To have a good structure, setting different parameters based on the
desired operation should not be interleaved with applying these
parameters to the hardware registers. Or in different words, the
parameter site should be mixed with the call site.

Thus, separate configuration and execution of an SMBus xfer within
rtl9300_i2c_smbus_xfer to improve readability and maintainability. Add a
new 'struct rtl9300_i2c_xfer' to carry the required parameters for an
xfer which are configured based on the input parameters within a single
switch-case block, without having any function calls within this block.

The function calls to actually apply these values to the hardware
registers then appear below in a single place and just operate on the
passed instance of 'struct rtl9300_i2c_xfer'. These are
'rtl9300_i2c_prepare_xfer' which combines applying all parameters of the
xfer to the corresponding register, and 'rtl9300_i2c_do_xfer' which
actually executes the xfer and does post-processing if needed.

Signed-off-by: Jonas Jelonek <jelonek.jonas@gmail.com>
Tested-by: Sven Eckelmann <sven@narfation.org>
Reviewed-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Tested-by: Chris Packham <chris.packham@alliedtelesis.co.nz> # On RTL9302C based board
Tested-by: Markus Stockhausen <markus.stockhausen@gmx.de>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/r/20250927101931.71575-7-jelonek.jonas@gmail.com
2025-10-04 11:43:40 +02:00
arch bpf-next-6.18 2025-09-30 17:58:11 -07:00
block namespace-6.18-rc1 2025-09-29 11:20:29 -07:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto bpf-next-6.18 2025-09-30 17:58:11 -07:00
Documentation dt-bindings: i2c: realtek,rtl9301-i2c: fix wording and typos 2025-10-04 11:43:40 +02:00
drivers i2c: rtl9300: separate xfer configuration and execution 2025-10-04 11:43:40 +02:00
fs Driver core changes for 6.18-rc1 2025-10-01 08:39:23 -07:00
include i2c-for-6.18-rc1 2025-10-01 15:11:00 -07:00
init Updates for the VDSO subsystem: 2025-09-30 16:58:21 -07:00
io_uring io_uring-6.17-20250919 2025-09-19 12:10:49 -07:00
ipc namespace-6.18-rc1 2025-09-29 11:20:29 -07:00
kernel Driver core changes for 6.18-rc1 2025-10-01 08:39:23 -07:00
lib Updates for the VDSO subsystem: 2025-09-30 16:58:21 -07:00
LICENSES LICENSES: Replace the obsolete address of the FSF in the GFDL-1.2 2025-07-24 11:15:39 +02:00
mm arm64 updates for 6.18 2025-09-29 18:48:39 -07:00
net bpf-next-6.18 2025-09-30 17:58:11 -07:00
rust regulator: Updates for v6.18 2025-10-01 11:43:54 -07:00
samples Driver core changes for 6.18-rc1 2025-10-01 08:39:23 -07:00
scripts Rust changes for v6.18 2025-09-30 19:12:49 -07:00
security lsm/stable-6.18 PR 20250926 2025-09-30 08:48:29 -07:00
sound Pin control changes for the v6.18 kernel cycle: 2025-10-01 13:14:48 -07:00
tools nolibc changes for v6.18 2025-09-30 19:18:17 -07:00
usr usr/include: openrisc: don't HDRTEST bpf_perf_event.h 2025-05-12 15:03:17 +09:00
virt Merge tag 'kvm-x86-no_assignment-6.17' of https://github.com/kvm-x86/linux into HEAD 2025-07-29 08:36:42 -04:00
.clang-format Linux 6.15-rc5 2025-05-06 16:39:25 +10:00
.clippy.toml rust: clean Rust 1.88.0's warning about clippy::disallowed_macros configuration 2025-05-07 00:11:47 +02:00
.cocciconfig
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore MAINTAINERS: remove Alyssa Rosenzweig 2025-09-18 21:17:31 +02:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore gitignore: allow .pylintrc to be tracked 2025-07-02 17:10:04 -06:00
.mailmap 7 hotfixes. 4 are cc:stable and the remainder address post-6.16 issues or 2025-09-28 09:32:00 -07:00
.pylintrc docs: add a .pylintrc file with sys path for docs scripts 2025-04-09 12:10:33 -06:00
.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 MAINTAINERS: Delete inactive maintainers from AF_XDP 2025-09-25 13:18:22 +02:00
Kbuild sched: Make migrate_{en,dis}able() inline 2025-09-25 09:57:16 +02:00
Kconfig io_uring: Rename KConfig to Kconfig 2025-02-19 14:53:27 -07:00
MAINTAINERS MFD for v6.18 2025-10-01 12:04:12 -07:00
Makefile hardening updates for v6.18-rc1 2025-09-29 17:48:27 -07:00
README README: Fix spelling 2024-03-18 03:36:32 -06:00

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 reStructuredText 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.