i2c: uniphier: Use devm_clk_get_enabled()

Replace the pair of functions, devm_clk_get() and clk_prepare_enable(),
with a single function devm_clk_get_enabled().

Signed-off-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: 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: drivers: Use generic definitions for bus frequencies

Since we have generic definitions for bus frequencies, let's use them.

Reviewed-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Acked-by: Robert Richter <rrichter@marvell.com>
Reviewed-by: Thor Thayer <thor.thayer@linux.intel.com>
Acked-by: Elie Morisse <syniurge@gmail.com>
Acked-by: Nehal Shah <nehal-bakulchandra.shah@amd.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Acked-by: Scott Branden <scott.branden@broadcom.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Baruch Siach <baruch@tkos.co.il>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Vladimir Zapolskiy <vz@mleia.com>
Acked-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Chris Brandt <chris.brandt@renesas.com>
Reviewed-by: Baolin Wang <baolin.wang7@gmail.com>
Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com>
Acked-by: Patrice Chotard <patrice.chotard@st.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: uniphier(-f): remove all dev_dbg()

I have fixed various bugs, and these drivers are (I hope) pretty
stable now. Remove all dev_dbg() for code clean-up.

If I end up with debugging the drivers again, I will locally revert
this commit. I no longer need the debug code in upstream.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: uniphier(-f): use devm_platform_ioremap_resource()

Replace the chain of platform_get_resource() and devm_ioremap_resource()
with devm_platform_ioremap_resource().

This allows to remove the local variable for (struct resource *), and
have one function call less.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157

Based on 3 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 either version 2 of the license or at
your option any later version 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

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 either version 2 of the license or at
your option any later version [author] [kishon] [vijay] [abraham]
[i] [kishon]@[ti] [com] 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

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 either version 2 of the license or at
your option any later version [author] [graeme] [gregory]
[gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
[kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
[hk] [hemahk]@[ti] [com] 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-or-later

has been chosen to replace the boilerplate/reference in 1105 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

i2c: uniphier: fix violation of tLOW requirement for Fast-mode

Currently, the clock duty is set as tLOW/tHIGH = 1/1. For Fast-mode,
tLOW is set to 1.25 us while the I2C spec requires tLOW >= 1.3 us.

tLOW/tHIGH = 5/4 would meet both Standard-mode and Fast-mode:
Standard-mode: tLOW = 5.56 us, tHIGH = 4.44 us
Fast-mode: tLOW = 1.39 us, tHIGH = 1.11 us

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: uniphier: issue STOP only for last message or I2C_M_STOP

This driver currently emits a STOP if the next message is not
I2C_MD_RD. It should not do it because it disturbs the I2C_RDWR
ioctl, where read/write transactions are combined without STOP
between.

Issue STOP only when the message is the last one _or_ flagged with
I2C_M_STOP.

Fixes: dd6fd4a32793 ("i2c: uniphier: add UniPhier FIFO-less I2C driver")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: uniphier: add suspend / resume support

When resuming, set up registers that have been lost in the sleep state.
Also, add clock handling in the resume / suspend hooks.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: uniphier: rename jump label to follow coding style guideline

Documentation/CodingStyle recommends to use label names which say
what the goto does or why the goto exists.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: uniphier: avoid WARN_ON() of clk_disable() in failure path

If clk_prepare_enable() fails, clk_disable_unprepare() is called in
the failure path, where the enable_count is still zero, so it hits
WARN_ON(core->enable_count == 0) in the clk_core_disable().

To fix this, make the clock setting more linear in the probe function
so that it can exploit "goto err" in case of error.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: uniphier{-f}: 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>
Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: uniphier: add "\n" at the end of error log

Just in case.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: uniphier: fix typos in error messages

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: uniphier: error out if bus speed is zero

There is code to divide by "bus_speed" some lines below.
To eliminate the possibility of division by zero, bail out if
"clock-frequency" is specified as zero.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: uniphier: error out if clock rate is zero

This input clock is used to generate the sampling clock for I2C bus.
If the clock rate is zero, there is something wrong with the clock
driver. Bail out with the appropriate error message in such a case.
It would make it easier to find the root cause of failure.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: uniphier: add UniPhier FIFO-less I2C driver

Add support for on-chip I2C controller used on old UniPhier SoCs
such as PH1-LD4, PH1-sLD8, etc. This adapter is so simple that
it has no FIFO in it.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>