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Harshal Gohel d3c2191d49 i2c: rtl9300: Implement I2C block read and write
It was noticed that the original implementation of SMBus Block Write in the
driver was actually an I2C Block Write. Both differ only in the Count byte
before the actual data:

  S Addr Wr [A] Comm [A] Count [A] Data [A] Data [A] ... [A] Data [A] P

The I2C Block Write is just skipping this Count byte and starts directly
with the data:

  S Addr Wr [A] Comm [A] Data [A] Data [A] ... [A] Data [A] P

The I2C controller of RTL93xx doesn't handle this Count byte special and it
is simply another one of (16 possible) data bytes. Adding support for the
I2C Block Write therefore only requires skipping the count byte (0) in
data->block.

It is similar for reads. The SMBUS Block read is having a Count byte before
the data:

  S Addr Wr [A] Comm [A]
            Sr Addr Rd [A] [Count] A [Data] A [Data] A ... A [Data] NA P

And the I2C Block Read is directly starting with the actual data:

  S Addr Wr [A] Comm [A]
            Sr Addr Rd [A] [Data] A [Data] A ... A [Data] NA P

The I2C controller is also not handling this byte in a special way. It
simply provides every byte after the Rd marker + Ack as part of the 16 byte
receive buffer (registers). The content of this buffer just has to be
copied to the right position in the receive data->block.

Signed-off-by: Harshal Gohel <hg@simonwunderlich.de>
Co-developed-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Reviewed-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Tested-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Reviewed-by: Jonas Jelonek <jelonek.jonas@gmail.com>
Tested-by: Jonas Jelonek <jelonek.jonas@gmail.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://lore.kernel.org/all/20250927-i2c-rtl9300-multi-byte-v7-2-c0fd0e78b818@narfation.org
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 i2c-for-6.18-rc1 2025-10-01 15:11:00 -07:00
drivers i2c: rtl9300: Implement I2C block read and write 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.