History log of /linux-master/drivers/i2c/busses/i2c-sh_mobile.c
Revision Date Author Comments
# 7a7fd335 31-Jan-2024 Geert Uytterhoeven <geert+renesas@glider.be>

i2c: sh_mobile: Switch R-Mobile A1/APE6 and SH-Mobile AG5 to new frequency calculation

Switch the R-Mobile A1, R-Mobile APE6, and SH-Mobile AG5 SoCs to the new
frequency calculation formula, to (a) avoid running the I2C bus too fast,
and (b) bring the low/high ratio closer to the recommended ratio 5/4.

As this makes fast_clock_dt_config and v2_freq_calc_dt_config identical,
merge them into a single fast_clock_dt_config.

Legacy SH users (sh7343, sh7366, and sh772[234]) are left alone, and
still use the old formula.

Measurement results on R-Mobile APE6 and SH-Mobile AG5 (fck=104 MHz,
clks_per_count=2):
100 kHz: 106 kHz LH=1.12 before, 99.6 kHz L/H=1.22 after
400 kHz: 384 kHz LH=1.67 before, 392 kHz L/H=1.27 after

Measurement results on R-Mobile A1 (fck=49.5 MHz, clks_per_count=1):
100 kHz: 106 kHz L/H=1.09 before, 99.6 kHz L/H=1.20 after

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>


# 3735e431 10-Jul-2023 Yangtao Li <frank.li@vivo.com>

i2c: sh_mobile: Use devm_platform_get_and_ioremap_resource()

Convert platform_get_resource(), devm_ioremap_resource() to a single
call to devm_platform_get_and_ioremap_resource(), as this is exactly
what this function does.

Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>


# 59738ab2 14-Jul-2023 Rob Herring <robh@kernel.org>

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>


# 426b6742 22-Jul-2023 Paul Cercueil <paul@crapouillou.net>

i2c: sh-mobile: Remove #ifdef guards for PM related functions

Use the new PM macros for the suspend and resume functions to be
automatically dropped by the compiler when CONFIG_PM or
CONFIG_PM_SLEEP are disabled, without having to use #ifdef guards.

This has the advantage of always compiling these functions in,
independently of any Kconfig option. Thanks to that, bugs and other
regressions are subsequently easier to catch.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20230722115310.27681-4-paul@crapouillou.net
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>


# e190a0c3 08-May-2023 Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

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>


# ea1558ce 11-Aug-2022 Wolfram Sang <wsa+renesas@sang-engineering.com>

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>


# bf3c39f5 07-Jan-2022 Yang Li <yang.lee@linux.alibaba.com>

i2c: sh_mobile: remove unneeded semicolon

Eliminate the following coccicheck warning:
./drivers/i2c/busses/i2c-sh_mobile.c:849:3-4: Unneeded semicolon

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@kernel.org>


# aab799e4 21-Dec-2021 Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

i2c: sh_mobile: Use platform_get_irq_optional() to get the interrupt

platform_get_resource(pdev, IORESOURCE_IRQ, ..) relies on static
allocation of IRQ resources in DT core code, this causes an issue
when using hierarchical interrupt domains using "interrupts" property
in the node as this bypasses the hierarchical setup and messes up the
irq chaining.

In preparation for removal of static setup of IRQ resource from DT core
code use platform_get_irq_optional() for DT users only.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>


# 44df8a79 08-Dec-2021 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: update to new DMAENGINE API when terminating

dmaengine_terminate_all() is deprecated. When converting the existing
calls, it turned out that the termination in the DMA setup and callback
were superfluous and only a side effect of simply calling
rcar_i2c_cleanup_dma(). As either no DMA transfers have been submitted
yet or the last one has successfully completed, there is nothing to
terminate and we can leave it out. So, merge the DMA unmap and cleanup
function to save some code. Then, add a flag if the new cleanup function
needs to terminate DMA. This is only the case for the erorr handling in
the main thread, so we can finally switch from dmaengine_terminate_all()
to dmaengine_terminate_sync() here.

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


# e5a7cb0d 23-Jun-2021 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: : use proper DMAENGINE API for termination

dmaengine_terminate_all() is deprecated in favor of explicitly saying if
it should be sync or async. Here, we want dmaengine_terminate_sync()
because there is no other synchronization code in the driver to handle
an async case.

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


# c4740e29 06-May-2021 Geert Uytterhoeven <geert+renesas@glider.be>

i2c: sh_mobile: Use new clock calculation formulas for RZ/G2E

When switching the Gen3 SoCs to the new clock calculation formulas, the
match entry for RZ/G2E added in commit 51243b73455f2d12 ("i2c:
sh_mobile: Add support for r8a774c0 (RZ/G2E)") was forgotten.

Fixes: e8a27567509b2439 ("i2c: sh_mobile: use new clock calculation formulas for Gen3")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>


# e8a61e5a 13-Oct-2020 Geert Uytterhoeven <geert+renesas@glider.be>

i2c: sh_mobile: Mark adapter suspended during suspend

When a driver tries to send an I2C message while the adapter is
suspended, this typically fails with:

i2c-sh_mobile e60b0000.i2c: Transfer request timed out

Avoid accessing the adapter while it is suspended by marking it
suspended during suspend. This allows the I2C core to catch this, and
print a warning:

WARNING: CPU: 1 PID: 13 at drivers/i2c/i2c-core.h:54
__i2c_transfer+0x4a4/0x4e4
i2c i2c-6: Transfer while suspended

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@kernel.org>


# a49cc1fe 28-Sep-2020 Ulrich Hecht <uli+renesas@fpond.eu>

i2c: sh_mobile: implement atomic transfers

Implements atomic transfers to fix reboot/shutdown on r8a7790 Lager and
similar boards.

Signed-off-by: Ulrich Hecht <uli+renesas@fpond.eu>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
[wsa: some whitespace fixing]
Signed-off-by: Wolfram Sang <wsa@kernel.org>


# f80531c8 11-Jun-2020 Jarkko Nikula <jarkko.nikula@linux.intel.com>

i2c: Use separate MODULE_AUTHOR() statements for multiple authors

Modules with multiple authors should use multiple MODULE_AUTHOR()
statements according to comment in include/linux/module.h.

Split the i2c modules with multiple authors to use multiple
MODULE_AUTHOR() statements.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>


# 34765c19 08-May-2019 Viresh Kumar <viresh.kumar@linaro.org>

i2c: sh_mobile: simplify code and remove false compilation warning

This currently generates a warning:

drivers/i2c/busses/i2c-sh_mobile.c: In function 'sh_mobile_i2c_isr':
drivers/i2c/busses/i2c-sh_mobile.c:399:26: warning: 'data' may be used uninitialized in this function [-Wmaybe-uninitialized]

Though the code looks okay and shouldn't ever use the variable
uninitialized. Fix the warning by moving the code around and getting rid
of 'data'.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
[wsa: minor updates to commit message]
Signed-off-by: Wolfram Sang <wsa@kernel.org>


# 90224e64 24-Mar-2020 Andy Shevchenko <andriy.shevchenko@linux.intel.com>

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>


# efa42b5e 13-Nov-2019 Peter Ujfalusi <peter.ujfalusi@ti.com>

i2c: sh_mobile: Use dma_request_chan() directly for channel request

dma_request_slave_channel_reason() is:
dma_request_chan(dev, name)

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 8fbd9b08 05-Feb-2019 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: use new clock calculation formulas for Gen2

We measured the clock on a Lager and an Ebisu board. The new formula
gives better results for both. So after Gen3, switch to this formula for
all Gen2 SoCs.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# e8a27567 04-Feb-2019 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: use new clock calculation formulas for Gen3

We could finally measure the clock on an Ebisu board. The new formula
gives way better results, i.e. 100kHz instead of 106kHz and 400kHz
instead of 387kHz. Switch to these formulas for all Gen3 SoCs.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 43116a0d 04-Feb-2019 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: sort compatible entries

Makes it easier to add new ones.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 9d899ed4 16-Jan-2019 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: update copyright and comments

Update copyright years and add Renesas to it. Add/update comments to
make driver easier to understand.

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


# 63c52460 16-Jan-2019 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: refactor rx isr

Remove the do_while loop which was just there to have an easy exit with
"break;" and replace it with if-else-blocks which should make the state
machine clearer.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 0130e3bf 16-Jan-2019 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: replace break; with if-block

In preparation to remove the do-while-loop.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# e659f36d 16-Jan-2019 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: remove is_first_byte function

All state machines deal with pd->pos values. This helper function is an
exception and makes it only more confusing.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# d16f2bfe 16-Jan-2019 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: drop 'data' argument from i2c_op function

It is clear that we always send the address in TX_FIRST and data in TX.
No need to pass it from the caller.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 1f32fbdf 16-Jan-2019 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: remove get_data function

It makes the code much easier comprehensible to explicitly code that the
first byte will be client address and all the following bytes are the
actual data.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 5b3e3b43 16-Jan-2019 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: simplify sending address for RX

pd->pos won't be smaller than -1, so we can simplify the logic.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 51243b73 13-Dec-2018 Fabrizio Castro <fabrizio.castro@bp.renesas.com>

i2c: sh_mobile: Add support for r8a774c0 (RZ/G2E)

Similarly to R-Car E3, RZ/G2E doesn't come with automatic
transmission registers, as such it is not considered compatible
with the existing fallback bindings.

Add SoC specific binding compatibility to allow for later
support for automatic transmission.

Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 5eb316e6 21-Nov-2018 Simon Horman <horms+renesas@verge.net.au>

i2c: sh_mobile: add support for r8a77990 (R-Car E3)

Add support for the IIC code for the r8a77990 (R-Car E3).

It is not considered compatible with existing fallback bindings
due to the documented absence of automatic transmission registers.

These registers are currently not used by the driver and
thus the provides the same behaviour for "renesas,iic-r8a77990" and
"renesas,rcar-gen3-iic". The point of declaring incompatibility is
to allow for automatic transmission register support to be added to
"renesas,iic-r8a77990" and "renesas,rcar-gen3-iic" in future.

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 7ce6c65b 24-Oct-2018 Jarkko Nikula <jarkko.nikula@linux.intel.com>

i2c: sh_mobile: Remove dummy runtime PM callbacks

Platform drivers don't need dummy runtime PM callbacks that just return
success and non-NULL pm pointer in their struct device_driver in order
to have runtime PM happening. This has changed since following commits:

05aa55dddb9e ("PM / Runtime: Lenient generic runtime pm callbacks")
543f2503a956 ("PM / platform_bus: Allow runtime PM by default")
8b313a38ecff ("PM / Platform: Use generic runtime PM callbacks directly")

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# cebc07d8 24-Aug-2018 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: fix leak when using DMA bounce buffer

We only freed the bounce buffer after successful DMA, missing the cases
where DMA setup may have gone wrong. Use a better location which always
gets called after each message and use 'stop_after_dma' as a flag for a
successful transfer.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 531db501 24-Aug-2018 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: define start_ch() void as it only returns 0 anyhow

After various refactoring over the years, start_ch() doesn't return
errno anymore, so make the function return void. This saves the error
handling when calling it which in turn eases cleanup of resources of a
future patch.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 82fe39a6 24-Aug-2018 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: refactor function to release a DMA safe buffer

a) rename to 'put' instead of 'release' to match 'get' when obtaining
the buffer
b) change the argument order to have the buffer as first argument
c) add a new argument telling the function if the message was
transferred. This allows the function to be used also in cases
where setting up DMA failed, so the buffer needs to be freed without
syncing to the message buffer.

Also convert the only user.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 6055af5e 21-Aug-2018 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: use SPDX identifier for Renesas drivers

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 7957c2e2 23-Jul-2018 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: use core to detect 'no zero length read' quirk

And don't reimplement in the driver.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 77bade67 29-Apr-2018 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: busses: remove superfluous ignoring of children for RPM

These days, the I2C core ensures that the embedded adapter device
ignores the PM states of its children already. Because the adapter
device is an opaque logical device, there is no need for drivers to
repeat that again.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 6e318d9e 18-Dec-2017 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: let r8a7790 (R-Car H2) use the new formula

Make use of the new formula for more precise bus frequencies.

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


# 4ecfb9d3 18-Dec-2017 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: add new frequency calculation for later SoC

The formula to generate the desired bus speeds has changed a little over
time. Implement the new formula and allow drivers to opt-in by changing
to this new config set. Ensure in probe that we don't divide by zero.
The returned values on a R-Car H2 (r8a7790/Lager board) match the
suggested values in the datasheet.

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


# c3449f73 18-Dec-2017 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: add helper to check frequency calculations

Because we will add a second formula soon, put the sanity checks for the
computed results into a separate function.

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


# 023c22fd 18-Dec-2017 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: let RuntimePM do the clock handling

Start RuntimePM a bit earlier, so we can use it to enable the clock
during probe for frequency calculations. Make sure it is enabled before
calling setup().

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


# b3750b62 18-Dec-2017 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: require setup callback

Require the setup callback and move the frequency calculation into it.
This is in preparation for supporting multiple formulas.

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


# 12742b6a 18-Dec-2017 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: allow setup callback to return errno

The setup callback will be more generic and, thus, need to be able to
return error codes. Change the return type to 'int' for that.

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


# 9e422131 18-Dec-2017 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: move type detection upwards

For refactoring reasons, we will need this information before the setup
callback. Also, simplify the comment to a oneliner.

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


# fe23aa9a 04-Nov-2017 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: use core helper to decide when to use DMA

This ensures that we fall back to PIO if the message length is too small
for DMA being useful. Otherwise, we use DMA. A bounce buffer might be
applied by the helper if the original message buffer is not DMA safe.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 4ed152c4 15-Nov-2017 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: make sure to not accidently trigger STOP

The datasheet was a bit vague, but after consultation with HW designers,
we came to the conclusion that we should set the SCP bit always when
dealing only with the ICE bit. A set SCP bit is ignored, and thus fine,
a cleared one may trigger STOP on the bus.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# a4fde7e5 09-Nov-2017 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: send STOP according to datasheet

We initiate STOP (or REP_START) on the second last WAIT interrupt
currently. This works fine but is not according to the datasheet which
says to do it on the last WAIT interrupt. This also simplifies the code
quite a lot, so let's do it.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Tested-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 2967f9ca 09-Nov-2017 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: avoid unnecessary register read

There is no data when the first WAIT interrupt arrives. No need to read
something then.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 91701ae8 08-Nov-2017 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: let RuntimePM do the clock handling

No need to do it manually.

Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# a4d16493 02-Nov-2017 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: shorten exit of xfer routine

We can use the ternary operator for easier reading.

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


# 832a522a 02-Nov-2017 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: use direct writes when accessing ICE bit

ICE bit is for resetting the module. Other bits don't matter then, so we
don't need to use the iic_set_clr() function but can use iic_wr().

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


# 91a5e63e 02-Nov-2017 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: manually "inline" two short functions

Those two functions are very short and only called once. The code
becomes easier to understand if the code is directly put into the main
xfer function.

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


# 3f3a5139 02-Nov-2017 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: remove redundant deinitialization

No need to clear the interrupt registers because right after that we
disable the IP core which will reload registers with their initial
values anyhow.

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


# f289800a 02-Nov-2017 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: remove redundant initialization

Following the documentation, we initialize the HW before each START in
start_ch(). No need to do the same in activate_ch().

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


# ad59c5ea 04-Oct-2017 Geert Uytterhoeven <geert+renesas@glider.be>

i2c: sh_mobile: Use of_device_get_match_data() helper

Use the of_device_get_match_data() helper instead of open coding.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 75fdc518 15-Aug-2017 Eugeniu Rosca <erosca@de.adit-jv.com>

i2c: sh_mobile: avoid unused ret variable

Fix smatch warning:
drivers/i2c/busses/i2c-sh_mobile.c:564 \
sh_mobile_i2c_request_dma_chan() warn: unused return: ret = PTR_ERR()

Signed-off-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 90b84c05 18-May-2017 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: drop needless check for of_node

After removal of platform_data support, we can simplify OF handling.
of_match_device() evaluates to NULL if !CONFIG_OF or if there is no node
pointer for that device, so we can remove the check for the node ptr.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# d2f31c49 18-May-2017 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: remove platform_data

No platform currently upstream makes use of this platform_data anymore.
The ones that did are converted to DT meanwhile. So, remove it. The old
platforms likely don't have the 'clks_per_cnt' feature, otherwise it
would have been implemented by now. And in the unlikely case they need
to setup a different bus speed, we should rather go for a generic i2c
platform data just for that.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 92d9d0df 27-Jan-2017 Bhumika Goyal <bhumirks@gmail.com>

i2c: busses: constify i2c_algorithm structures

Declare i2c_algorithm structures as const as they are only stored in the
algo field of an i2c_adapter structure. This field is of type const, so
i2c_algorithm structures having this property can be made const too.

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> for
Acked-by: Patrice Chotard <patrice.chotard@st.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# b880ccaf 07-Dec-2016 Simon Horman <horms+renesas@verge.net.au>

i2c: sh_mobile: Add per-Generation fallback bindings

Add per-Generation fallback bindings for R-Car SoCs.

This is in keeping with the compatibility string scheme is being adopted
for drivers for Renesas SoCs.

Also, improve readability by listing the rmobile fallback compatibility
string after the more-specific compatibility strings they provide a
fallback for.

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 488d69ea 24-Aug-2016 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: use proper device with dma_mapping_error

We must use the same device we used for mapping.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# ea734404 09-Aug-2016 Wolfram Sang <wsa-dev@sang-engineering.com>

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>


# 3f8a57bb 03-Apr-2016 Wolfram Sang <wsa@kernel.org>

i2c: sh_mobile: use new 8 bit address helper function

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


# 7bb6da5a 05-Aug-2015 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: add support for r8a7795 (R-Car H3)

Enable the I2C core for this SoC. It is compitable to Gen2 SoCs, so
reuse the settings.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 365322fb 20-Jun-2015 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: use proper type for timeout

wait_event_timeout returns long, not int.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 41bdbd28 20-Jun-2015 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: use adapter default for timeout

5 seconds is a very large timeout, and it is hardcoded. Use the default
timeout from 'struct adapter' which is 1 second. It can also be modified
from userspace for specific workloads via i2c-dev.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 3ded3743 09-Jun-2015 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: add errata workaround

This used to be in platform init code. We want it to do in the driver
now. This is basically a code move and a new compatible added.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 32e22409 29-Jan-2015 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: terminate DMA reads properly

DMA read requests could miss proper termination, so two more bytes would
have been read via PIO overwriting the end of the buffer with wrong
data. Make DMA stop handling more readable while we are here.

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


# fe07adec 16-Dec-2014 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: fix uninitialized var when debug is enabled

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


# 55f5f986 16-Dec-2014 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: rework deferred probing

DMA is opt-in for this driver. So, we can't use deferred probing for
requesting DMA channels in probe, because our driver would get endlessly
deferred if DMA support is compiled in AND the DMA driver is missing.
Because we can't know when the DMA driver might show up, we always try
again when a DMA transfer would be possible. The downside is that there
is more overhead for setting up PIO transfers under the above scenario.
But well, having DMA enabled and the proper DMA driver missing looks
like a broken or test config anyhow.

Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# e844a799 16-Dec-2014 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: refactor DMA setup

Refactor DMA setup to keep the errno so we can implement better
deferred probe support in the next step.

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


# 6cf710d4 10-Dec-2014 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: remove unneeded DMA mask

We don't need the mask since we obtain the channels via DT.

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


# 530834b1 04-Dec-2014 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: optimize irq entry

We can simply pass the pointer to the private structure to the irq
routine instead of passing the platform device and looking up its
driver_data.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 8cfcae9f 19-Nov-2014 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: use proper device for mapping DMA memory

It should be the DMA device, not the platform device.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 7ca01864 07-Nov-2014 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: improve success message

No user needs magic hex values, makes this debug output. Add DMA info.

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


# 2d09581b 07-Nov-2014 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: add DMA support

Make it possible to transfer i2c message buffers via DMA.
Start/Stop/Sending_Slave_Address is still handled using the old state
machine, it is sending the actual data that is done via DMA. This is
least intrusive and allows us to work with the message buffers directly
instead of preparing a custom buffer which involves copying the data
around.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
[wsa: fixed an uninitialized var problem]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 5bbe6879 07-Nov-2014 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: sort includes alphabetically

Improves readability and reduces chances of duplicates.

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


# 78df445e 05-Nov-2014 Geert Uytterhoeven <geert+renesas@glider.be>

i2c: sh_mobile: Add support for r8a73a4 and sh73a0

Add support for r8a73a4 (R-Mobile APE6) and sh73a0 (SH-Mobile AG5).
On these SoCs, the operating clock runs faster that on previous SoCs,
and the internal SCL clock counter gets incremented every 2 clocks of
the operating clock, just like on R-Car Gen2.

Cfr. the "/2" in the calculation of ICCL/ICCH in section "I2C Bus
Interface (IIC)", subsection "Transfer Rate" of the datasheets.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# ca1f8da9 04-Nov-2014 Wolfram Sang <wsa+renesas@sang-engineering.com>

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>


# 1ecc4335 20-Oct-2014 Wolfram Sang <wsa@kernel.org>

i2c: busses: drop owner assignment from platform_drivers

A platform_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 90104d06 27-May-2014 Wolfram Sang <wsa@sang-engineering.com>

i2c: sh_mobile: add compatibles for additional SoC

Signed-off-by: Wolfram Sang <wsa@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 67240dfc 02-May-2014 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: fix clock calculation for newer SoCs

Newer SoCs have so fast input clocks that the ICCL/H registers only
count every second clock to have a meaningful 9-bit range. The driver
was already prepared for that happening, but didn't use it so far.
Add the proper DT configuration for SoCs that need it.

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


# 7663ebef 02-May-2014 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: check timing parameters for valid range

Due to misconfiguration, it can happen that the calculated timing
parameters are out of range. Bail out if that happens. We can also
simplify some logic later because of the verified value. Also, make the
printouts of the values more precise by adding the hex-prefixes.

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


# 6ed7053c 02-May-2014 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: bail out on errors when initializing

sh_mobile_i2c_init() could detect wrong settings, but didn't bail out,
so it would continue unconfigured. Fix this.

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


# ed4121e1 02-May-2014 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: remove superfluous offset parameter

Following the KISS principle, remove unneeded stuff.

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


# 7fe8a999 02-May-2014 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: devm conversion, irq setup

This is what devm was made for. No rollback mechanism needed, remove the
hook parameter from the irq setup function and simplify it. While we are
here change some variables to proper types.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 4fd31c2e 02-May-2014 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: devm conversion, low hanging fruits

Convert the easy parts to devm. irqs will be converted in a seperate
patch to keep diffs readable.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 88c289ec 02-May-2014 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: honor DT bus speed settings

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


# 5a72b25e 02-May-2014 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: improve error handling

Use standard i2c error codes for i2c failures. Also, don't print
something on timeout since it happens regularly with i2c. Simplify some,
logic, too.

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


# a78f6a41 02-May-2014 Wolfram Sang <wsa+renesas@sang-engineering.com>

i2c: sh_mobile: replace magic hex values with constants

No functional change, binaries are identical.

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


# f887605d 28-Oct-2013 Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

i2c: sh_mobile: Convert to clk_prepare/unprepare

Turn clk_enable() and clk_disable() calls into clk_prepare_enable() and
clk_disable_unprepare() to get ready for the migration to the common
clock framework.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 687b81d0 10-Jul-2013 Wolfram Sang <wsa@kernel.org>

i2c: move OF helpers into the core

I2C of helpers used to live in of_i2c.c but experience (from SPI) shows
that it is much cleaner to have this in the core. This also removes a
circular dependency between the helpers and the core, and so we can
finally register child nodes in the core instead of doing this manually
in each driver. So, fix the drivers and documentation, too.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# 6d4028c6 30-Jul-2013 Jingoo Han <jg1.han@samsung.com>

i2c: use dev_get_platdata()

Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>


# e7890297 17-Jan-2013 Guennadi Liakhovetski <g.liakhovetski@gmx.de>

i2c: sh_mobile: don't send a stop condition by default inside transfers

By default there should be no stop bit on I2C between single messages
within transfers. Fix the driver to comply and only send a stop bit at
the end of transfers or if I2C_M_STOP is set.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>


# 4b382318 17-Jan-2013 Guennadi Liakhovetski <g.liakhovetski@gmx.de>

i2c: sh_mobile: eliminate an open-coded "goto" loop

Eliminate an open-coded "goto" loop by introducing a function.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>


# 5687265b 17-Jan-2013 Guennadi Liakhovetski <g.liakhovetski@gmx.de>

i2c: sh_mobile: fix timeout error handling

In a timeout case return an error immediately from the driver's
.master_xfer() method, instead of continuing and letting higher layers
fail.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>


# 05cf9368 17-Jan-2013 Guennadi Liakhovetski <g.liakhovetski@gmx.de>

i2c: sh_mobile: cosmetic: trivially simplify 2 functions

Reduce 2 boolean functions from "if (condition) return 1; return 0;" to
"return condition;"

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>


# 0b255e92 27-Nov-2012 Bill Pemberton <wfp5p@virginia.edu>

i2c: remove __dev* attributes from subsystem

CONFIG_HOTPLUG is going away as an option. As result the __dev*
markings will be going away.

Remove use of __devinit, __devexit_p, __devinitdata, __devinitconst,
and __devexit.

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Acked-by: Peter Korsgaard <peter.korsgaard@barco.com> (for ocores and mux-gpio)
Acked-by: Havard Skinnemoen <hskinnemoen@gmail.com> (for i2c-gpio)
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn> (for puf3)
Acked-by: Barry Song <baohua.song@csr.com> (for sirf)
Reviewed-by: Jean Delvare <khali@linux-fr.org>
[wsa: Fixed "foo* bar" flaws while we are here]
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>


# 29fb08c3 24-Oct-2012 Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>

i2c: i2c-sh_mobile: fix spurious transfer request timed out

Ensure that any of preceding register write operations to the I2C
hardware block reached the module, and the write data is reflected
in the registers, before leaving the interrupt handler.

Otherwise, we'll suffer from spurious WAIT interrupts that lead to
'Transfer request timed out' message, and the transaction failed.

Reported-by: Teppei Kamijou <teppei.kamijou.yb@renesas.com>
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>


# ebd5ac16 24-Oct-2012 Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>

i2c: i2c-sh_mobile: support I2C hardware block with a faster operating clock

On newer SH-/R-Mobile SoCs, a clock supply to the I2C hardware block,
which is used to generate the SCL clock output, is getting faster than
before, while on the other hand, the SCL clock control registers, ICCH
and ICCL, stay unchanged in 9-bit-wide (8+1).

On such silicons, the internal SCL clock counter gets incremented every
2 clocks of the operating clock.

This patch makes it configurable through platform data.

Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>


# 23a61291 24-Oct-2012 Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>

i2c: i2c-sh_mobile: optimize ICCH/ICCL values according to I2C bus speed

ICCH/ICCL values is supposed to be calculated/optimized to strictly meet
the timing specs required by the I2C standard. The resulting I2C bus
speed does not matter at all, if it's less than 100 or 400 kHz.

With this change, sh_mobile_i2c_icch() is virtually identical to
sh_mobile_i2c_iccl(), but they're providing good descriptions of
SH-/R-Mobile I2C hardware spec, and I'd leave them as separated.

Also fix a typo in the comment, print icch/iccl values at probe, etc.

Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>

[wsa: squashed two patches for bisectability]

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>


# 7b0e6292 24-Oct-2012 Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>

i2c: i2c-sh_mobile: calculate clock parameters at driver probing time

Currently SCL clock parameters (ICCH/ICCL) are calculated in
activate_ch(), which gets called every time sh_mobile_i2c_xfer() is
processed, while each I2C bus speed is system-defined and in general
those parameters do not have to be updated over I2C transactions.

The only reason I could see having it transaction-time is to adjust
ICCH/ICCL values according to the operating frequency of the I2C
hardware block, in the face of DFS (Dynamic Frequency Scaling).

However, this won't be necessary.

The operating frequency of the I2C hardware block can change _even_
in the middle of I2C transactions. There is no way to prevent it
from happening, and I2C hardware block can work with such dynamic
frequency change, of course.

Another is that ICCH/ICCL clock parameters optimized for the faster
operating frequency, can also be applied to the slower operating
frequency, as long as slave devices work. However, the converse is
not true. It would violate SCL timing specs of the I2C standard.

What we can do now is to calculate the ICCH/ICCL clock parameters
according to the fastest operating clock of the I2C hardware block.
And if that's the case, that calculation should be done just once
at driver-module-init time.

This patch moves ICCH/ICCL calculating part from activate_ch() into
sh_mobile_i2c_init(), and call it from sh_mobile_i2c_probe().

Note that sh_mobile_i2c_init() just prepares clock parameters using
the clock rate and platform data provided, but does _not_ make any
hardware I/O accesses. We don't have to care about run-time PM
maintenance here.

Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>


# ad337074 30-Mar-2012 Magnus Damm <damm@opensource.se>

i2c: sh_mobile: add device tree support

This patch enables DT support for the IIC driver
used on SH-based SoCs such as sh7722 and sh7724
among others as well as SH-Mobile SoCs such as
sh7367, sh7377, sh7372, sh73a0 and r8a7740.

Tested with out-of-tree DT support code on the
sh7372 Mackerel board.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>


# 4311051c 21-Sep-2011 Yong Zhang <yong.zhang0@gmail.com>

i2c: irq: Remove IRQF_DISABLED

Since commit [c58543c8: genirq: Run irq handlers with interrupts disabled],
We run all interrupt handlers with interrupts disabled
and we even check and yell when an interrupt handler
returns with interrupts enabled (see commit [b738a50a:
genirq: Warn when handler enables interrupts]).

So now this flag is a NOOP and can be removed.

Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Barry Song <21cnbao@gmail.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>


# 81f81153 27-Apr-2011 Magnus Damm <damm@opensource.se>

i2c: i2c-sh_mobile bus speed platform data V2

Add support to the i2c-sh_mobile driver for setting
the I2C bus speed using platform data.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>


# 1082d5d2 21-Apr-2011 Magnus Damm <damm@opensource.se>

i2c: i2c-sh_mobile clock string removal

Remove the clock string magic from the i2c-sh_mobile driver
now when all platforms support clkdev properly.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>


# 7ef0c12a 15-Apr-2011 Guennadi Liakhovetski <g.liakhovetski@gmx.de>

i2c: add a module alias to the sh-mobile driver

This patch enables I2C driver autoloading on sh-mobile systems.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Reviewed-by: Simon Horman <horms@verge.net.au>
Cc: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>


# 82b20d8b 02-Aug-2010 Magnus Damm <damm@opensource.se>

i2c: i2c-sh_mobile irq rollback fix

Update the i2c-sh_mobile driver to properly free
interrupts. The function sh_mobile_i2c_hook_irqs()
is fixed so module both unload and load are working
as expected.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>


# 962b6032 11-Mar-2010 Magnus Damm <damm@opensource.se>

i2c: i2c-sh_mobile support for new ICIC bits

Add support for a new version of the IIC block
found in the SH-Mobile ARM line of processors.

Prototype patch written by Nishimoto-san.
Tested on sh7377 and sh7372.

Signed-off-by: NISHIMOTO Hiroki <nishimoto.hiroki@renesas.com>
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>


# 12a55f2d 11-Mar-2010 Magnus Damm <damm@opensource.se>

i2c: i2c-sh_mobile register access code break out

Break out register access functions in the
i2c-sh_mobile driver. This update should not
change any driver logic.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>


# 5a0e3ad6 24-Mar-2010 Tejun Heo <tj@kernel.org>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>


# 47145210 14-Dec-2009 Alexey Dobriyan <adobriyan@gmail.com>

const: constify remaining dev_pm_ops

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>


# f1a3b994 14-Aug-2009 Magnus Damm <damm@igel.co.jp>

i2c: Runtime PM for SuperH Mobile I2C

This patch modifies the SuperH Mobile I2C driver to support
Runtime PM. These changes is all that is needed for proper
Runtime PM support in this driver. Driver callbacks for
Runtime PM are empty because the device registers are always
re-initialized after pm_runtime_get_sync().

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>


# ccb3bc16 22-Jul-2009 Magnus Damm <damm@igel.co.jp>

i2c-sh_mobile: change module_init() to subsys_initcall()

Convert the i2c-sh_mobile i2c bus driver to use
subsys_initcall() instead of module_init().

This change makes the driver register a bit earlier which
together with earlier platform data moves the time for probe().
The earlier probe() makes it possible to use i2c_get_adapter()
and i2c_transfer() from device_initcall().

The same strategy is used by other i2c bus drivers such as
i2c-pxa.c and i2c-s3c2410.c.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
[ben-linux@fluff.org: minor subject updaye]
Signed-off-by: Ben Dooks <ben-linux@fluff.org>


# c690be1c 22-Jul-2009 Magnus Damm <damm@igel.co.jp>

i2c: change i2c-sh_mobile.c module_init() to subsys_initcall()

Convert the i2c-sh_mobile i2c bus driver to use
subsys_initcall() instead of module_init().

This change makes the driver register a bit earlier which
together with earlier platform data moves the time for probe().
The earlier probe() makes it possible to use i2c_get_adapter()
and i2c_transfer() from device_initcall().

The same strategy is used by other i2c bus drivers such as
i2c-pxa.c and i2c-s3c2410.c.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>


# 59330825 05-Jul-2009 Julia Lawall <julia@diku.dk>

i2c: Use resource_size

Use the function resource_size, which reduces the chance of introducing
off-by-one errors in calculating the resource size.

The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
struct resource *res;
@@

- (res->end - res->start) + 1
+ resource_size(res)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>


# 22e965c2 07-Jan-2009 Jean Delvare <khali@linux-fr.org>

i2c: Get rid of remaining bus_id access

Use dev_name(dev) instead of accessing dev.bus_id directly, as the
latter is going away soon.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Kay Sievers <kay.sievers@vrfy.org>


# a5616bd0 31-Oct-2008 Magnus Damm <damm@igel.co.jp>

sh: sh_mobile i2c clock framework support

Add clock framework support to the sh_mobile i2c driver and
adjust the processor specific code accordingly.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>


# bff4056c8 12-Nov-2008 Magnus Damm <damm@igel.co.jp>

i2c: fix i2c-sh_mobile rx underrun

Fix receive path underrun in i2c-sh_mobile driver.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>


# 4eb00c9f 27-Aug-2008 Magnus Damm <damm@igel.co.jp>

i2c: fix i2c-sh_mobile timing issues

This patch teaches the i2c-sh_mobile driver to make use of wait irqs.
Without this patch only dte irqs are used which may lead to overruns
and cases of missing stop and extra bytes being read on the i2c bus.

Use of wait irqs forces the hardware to pause and wait until the cpu
is ready. Polling is also reworked in this patch to fix ms delay issues.

Verified with bus analyzer and tested on MigoR and AP325RXA boards.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>


# da672773 22-Apr-2008 Magnus Damm <magnus.damm@gmail.com>

i2c: New driver for the SuperH Mobile I2C bus controller

This is V5 of the SuperH Mobile I2C Controller Driver. A simple Master
only driver for the I2C block included in processors such as sh7343,
sh7722 and sh7723. Tested on a sh7722 MigoR using a rs5c732b rtc.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>