i2c: move drivers from strlcpy to strscpy

Follow the advice of the below link and prefer 'strscpy'. Conversion is
easy because no driver used the return value and has been done with a
simple sed invocation.

Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

i2c: taos-evm: convert to use i2c_new_client_device()

Move away from the deprecated API and return the shiny new ERRPTR where
useful.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: taos-evm: Make structure tsl2550_info constant

Static structure tsl2550_info, of type i2c_board_info, is referenced
only twice: the first time in arguments to dev_info() (which does not
modify it) and the second time as the last argument to function
i2c_new_device() (where the corresponding parameter is declared as
const). As tsl2550_info is therefore never modified, make it const to
protect it from unintended modifications.
Issue found with Coccinelle.

Signed-off-by: Nishka Dasgupta <nishkadg.linux@gmail.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

docs: i2c: convert to ReST and add to driver-api bookset

Convert each file at I2C subsystem, renaming them to .rst and
adding to the driver-api book.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 285

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation version 2 of the license this program
is distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 100 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.918357685@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

i2c: taos-evm: Remove duplicate NULL check

Since i2c_unregister_device() became NULL-aware we may remove duplicate
NULL check.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: taos-evm: constify serio_device_id

serio_device_id are not supposed to change at runtime. All functions
working with serio_device_id provided by <linux/serio.h> work with
const serio_device_id. So mark the non-const structs as const.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: taos-evm: replace simple_strtoul by kstrtou8

The simple_strtoul function is marked as obsolete.
This patch replace it by kstrtou8.

Reviewed-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: LABBE Corentin <clabbe.montjoie@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: remove FSF address

We have a central copy of the GPL for that. Some addresses were already
outdated.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: taos-evm: Use module_serio_driver()

Get rid of some boilerplate code by using module_serio_driver().

Signed-off-by: Christoph Jaeger <christophjaeger@linux.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Update Jean Delvare's e-mail address

Signed-off-by: Jean Delvare <khali@linux-fr.org>

i2c: Remove unneeded xxx_set_drvdata(..., NULL) calls

There is simply no reason to be manually setting the private driver
data to NULL in the remove/fail to probe cases. This is just extra
cruft code that can be removed.

A few notes:
* Nothing relies on drvdata being set to NULL.
* The __device_release_driver() function eventually calls
dev_set_drvdata(dev, NULL) anyway, so there's no need to do it
twice.
* I verified that there were no cases where xxx_get_drvdata() was
being called in these drivers and checking for / relying on the NULL
return value.

This could be cleaned up kernel-wide but for now just take the baby
step and remove from the i2c subsystem.

Reported-by: Wolfram Sang <wsa@the-dreams.de>
Reported-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Peter Korsgaard <jacmet@sunsite.dk>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>

i2c-taos-evm: Fix log messages

* Print all error and information messages even when debugging is
disabled.
* Don't use adapter device to log messages before it is ready.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: stable@kernel.org

i2c-taos-evm: Switch echo off to improve performance

When echo is on, we waste time reading back our orders. Switching echo
off makes performance much better: SMBus byte data transactions are 47%
faster and byte transactions are 24% faster.

Signed-off-by: Jean Delvare <khali@linux-fr.org>

i2c: Consistently reject unsupported transactions

Many PC SMBus host controller drivers don't properly handle the case
where they are requested to achieve a transaction they do not support.
Update them so that the consistently print a warning message and
return a single error value in this case.

Signed-off-by: Jean Delvare <khali@linux-fr.org>

i2c: Convert most new-style drivers to use module aliasing

Based on earlier work by Jon Smirl and Jochen Friedrich.

Update most new-style i2c drivers to use standard module aliasing
instead of the old driver_name/type driver matching scheme. I've
left the video drivers apart (except for SoC camera drivers) as
they're a bit more diffcult to deal with, they'll have their own
patch later.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Jon Smirl <jonsmirl@gmail.com>
Cc: Jochen Friedrich <jochen@scram.de>

i2c: New bus driver for the TAOS evaluation modules

This is a new I2C bus driver for the TAOS evaluation modules. Developped
and tested on the TAOS TSL2550 EVM.

Signed-off-by: Jean Delvare <khali@linux-fr.org>