I2C: Explicitly include correct DT includes

The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it as merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.

Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

i2c: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Alain Volmat <alain.volmat@foss.st.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Acked-by: Jochen Friedrich <jochen@scram.de>
Acked-by: Peter Rosin <peda@axentia.se>
Acked-by: Vadim Pasternak <vadimp@nvidia.com>
Reviewed-by: Asmaa Mnebhi <asnaa@nvidia.com>
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Reviewed-by: Chris Pringle <chris.pringle@phabrix.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
Reviewed-by: Tali Perry <tali.perry@nuvoton.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

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: meson: fix typo in comment

Spelling mistake (triple letters) in comment.
Detected with the help of Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

i2c: meson: fix missing clk_disable_unprepare() on error in meson_i2c_probe()

Fix the missing clk_disable_unprepare() before return
from meson_i2c_probe() in the error handling case.

Fixes: a57f9b4dd6f5 ("i2c: meson: Use 50% duty cycle for I2C clock")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

i2c: meson: Use 50% duty cycle for I2C clock

The duty cycle of 33% is less than the required
by the I2C specs for the LOW period of the SCL
clock.

Move the duty cyle to 50% for 100Khz or lower
clocks, and (40% High SCL / 60% Low SCL) duty
cycle for clocks above 100Khz.

Signed-off-by: Lucas Tanure <tanure@linux.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

i2c: meson: Use _SHIFT and _MASK for register definitions

Differentiate between masks and shifts

Signed-off-by: Lucas Tanure <tanure@linux.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

i2c: meson: Fix wrong speed use from probe

Having meson_i2c_set_clk_div after i2c_add_adapter
causes issues for client drivers that try to use
the bus before the requested speed is applied.

The bus can be used just after i2c_add_adapter, so
move i2c_add_adapter to the final step as
meson_i2c_set_clk_div needs to be called before
the bus is used.

Fixes: 09af1c2fa490 ("i2c: meson: set clock divider in probe instead of setting it for each transfer")
Signed-off-by: Lucas Tanure <tanure@linux.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

i2c: meson: fixup rate calculation with filter delay

Apparently, 15 cycles of the peripheral clock are used by the controller
for sampling and filtering. Because this was not known before, the rate
calculation is slightly off.

Clean up and fix the calculation taking this filtering delay into account.

Fixes: 30021e3707a7 ("i2c: add support for Amlogic Meson I2C controller")
Signed-off-by: Nicolas Belin <nbelin@baylibre.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

i2c: meson: keep peripheral clock enabled

SCL rate appears to be different than what is expected. For example,
We get 164kHz on i2c3 of the vim3 when 400kHz is expected. This is
partially due to the peripheral clock being disabled when the clock is
set.

Let's keep the peripheral clock on after probe to fix the problem. This
does not affect the SCL output which is still gated when i2c is idle.

Fixes: 09af1c2fa490 ("i2c: meson: set clock divider in probe instead of setting it for each transfer")
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

i2c: meson: fix clock setting overwrite

When the slave address is written in do_start(), SLAVE_ADDR is written
completely. This may overwrite some setting related to the clock rate
or signal filtering.

Fix this by writing only the bits related to slave address. To avoid
causing unexpected changed, explicitly disable filtering or high/low
clock mode which may have been left over by the bootloader.

Fixes: 30021e3707a7 ("i2c: add support for Amlogic Meson I2C controller")
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

i2c: busses: remove duplicate dev_err()

it will print an error message by itself when platform_get_irq()
goes wrong. so don't need dev_err() in here again.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Suggested-by: Markus Elfring <Markus.Elfring@web.de>
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: busses: convert to devm_platform_ioremap_resource

use devm_platform_ioremap_resource() to simplify code, it
contains platform_get_resource and devm_ioremap_resource.

Reviewed-by: Barry Song <baohua@kernel.org>
Acked-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: Robert Richter <rrichter@marvell.com>
Acked-by: Thor Thayer <thor.thayer@linux.intel.com>
Acked-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: meson: implement the master_xfer_atomic callback

Boards with some of the 32-bit SoCs (mostly Meson8 and Meson8m2) use a
Ricoh RN5T618 PMU which acts as system power controller. The driver for
the system power controller may need to the I2C bus just before shutting
down or rebooting the system. At this stage the interrupts may be
disabled already.

Implement the master_xfer_atomic callback so the driver for the RN5T618
PMU can communicate properly with the PMU when shutting down or
rebooting the board. The CTRL register has a status bit which can be
polled to determine when processing has completed. According to the
public S805 datasheet the value 0 means "idle" and 1 means "running".

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
[wsa: converted some whitespace alignment]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 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 version 2 as
published by the free software foundation

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

i2c: meson: update with SPDX Licence identifier

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: meson: update doc description to fix build warnings

Add description for 'data' parameter and drop unused 'irq' memeber.

Here is the warnings:
drivers/i2c/busses/i2c-meson.c:103: warning: No description found for
parameter 'data'
drivers/i2c/busses/i2c-meson.c:103: warning: Excess struct member 'irq'
description in 'meson_i2c'

Reported-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Yixun Lan <yixun.lan@amlogic.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: meson: add configurable divider factors

This patch try to add support for I2C controller in Meson-AXG SoC,
Due to the IP changes between I2C controller, we need to introduce
a compatible data to make the divider factor configurable.

Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Jian Hu <jian.hu@amlogic.com>
Signed-off-by: Yixun Lan <yixun.lan@amlogic.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: meson: improve and simplify interrupt handler

The preceding changes in this patch series now allow to simplify
the interrupt handler significantly.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: meson: remove meson_i2c_write_tokens

meson_i2c_write_tokens is always called directly after
meson_i2c_prepare_xfer (and only then). So we can simplify the code by
removing meson_i2c_write_tokens and moving the two statements of
meson_i2c_write_tokens to the end of meson_i2c_prepare_xfer.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: meson: don't create separate token chain just for the stop command

We can directly add the stop token to the token chain including the
last transfer chunk. This is more efficient than creating a separate
token chain just for the stop command.
And it allows us to get rid of state STATE_STOP completely.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: meson: improve interrupt handler and detect spurious interrupts

If state is STATE_IDLE no interrupt should occur. Return IRQ_NONE
if such a spurious interrupt is detected.
Not having to take care of STATE_IDLE later in the interrupt handler
allows to further simplify the interrupt handler in subsequent
patches of this series.

In addition move resetting REG_CTRL_START bit to the start of the
interrupt handler to ensure that the start bit is always reset.
Currently the start bit is not reset for STATE_STOP because
i2c->state is set to STATE_IDLE.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: meson: remove variable count from meson_i2c_xfer

Variable count has always the same value as i, so we don't need it.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: meson: use full 12 bits for clock divider

The clock divider has 12 bits, splitted into a 10 bit field and a
2 bit field. The extra 2 bits aren't used currently.

Change this to use the full 12 bits and warn if the requested
frequency is too low.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: meson: use i2c core for DT clock-frequency parsing

We don't have to parse the DT manually to retrieve the bus frequency
and we don't have to maintain an own default for the bus frequency.
Let the i2c core do this for us.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: meson: set clock divider in probe instead of setting it for each transfer

The bus frequency is fixed to what is set DT, therefore we can set
the clock divider in probe already and we don't have to set it for
each transfer.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: meson: remove member irq from struct meson_i2c

Member irq can be replaced with a local variable in probe
because it's nowhere else accessed.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: meson: use min instead of min_t where min_t isn't needed

Use min instead of min_t where min_t isn't needed.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: meson: fix wrong variable usage in meson_i2c_put_data

Most likely a copy & paste error.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Acked-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Fixes: 30021e3707a7 ("i2c: add support for Amlogic Meson I2C controller")

i2c: meson: add gxbb compatible string

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Acked-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: don't print error when adding adapter fails

The core will do this for us now.

Signed-off-by: Wolfram Sang <wsa-dev@sang-engineering.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Acked-by: Peter Korsgaard <peter@korsgaard.com>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Ray Jui <ray.jui@broadcom.com>
Acked-by: Vladimir Zapolskiy <vz@mleia.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: meson: Use complete() instead of complete_all()

There is only one waiter for the completion, therefore there
is no need to use complete_all(). Let's make that clear by
using complete() instead of complete_all().

The usage pattern of the completion is:

meson_i2c_xfer_msg()
reinit_completion()
...
/* Start the transfer */
...
wait_for_completion_timeout()

Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: meson: Fix module autoload for OF platform driver

This platform driver has a OF device ID table but the OF module
alias information is not created so module autoloading won't work.

Signed-off-by: Luis de Bethencourt <luisbg@osg.samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: add support for Amlogic Meson I2C controller

This is a driver for the I2C controller found in Amlogic Meson SoCs.

Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>