I think it is clear enough if we have the explanation once and make it
clear it is applicable for both SCL and SDA. Reword it a little with
the help of Simon's native language skills :)
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

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

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

Makes it easier to add new ones.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This augments the CBUS GPIO I2C driver to use GPIO
descriptors for clock, sel and data. We drop the platform
data that was only used for carrying GPIO numbers and
use machine descriptor tables instead.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Tested-by: NAaro Koskinen <aaro.koskinen@iki.fi>
Acked-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Update copyright years and remove a comment which grew incorrect and
useless over time.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

We don't use SPHINX currently in I2C documentation; but preparing the
I2C fault injector docs already is a good idea since it makes it easier
to read. Especially as new stuff is going to be added soon.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

There is no value in chronological sorting. Make it easier to follow for
humans.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Completion_done() is useless when we don't use its return value,
so we remove it.
Signed-off-by: Nqii wang <qii.wang@mediatek.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Different speeds have been defined by macros,
so we use macros definitions.
Signed-off-by: Nqii wang <qii.wang@mediatek.com>
Reviewed-by: NNicolas Boichat <drinkcat@chromium.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Add MT7629 i2c binding to binding file.
Signed-off-by: Nqii wang <qii.wang@mediatek.com>
Reviewed-by: NRob Herring <robh@kernel.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Less risk for duplications when adding new ones.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

And use kernel style for the remaining comments in the header.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

We are using symbols from it, so we should include it directly. Found
after sorting includes in a driver.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This adds device tree probing support for the IOP3xx
I2C master.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This adds a device tree binding for Intel XScale I2C
masters. We define compatible strings for the iop3xx and
ixp4xx chip families.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

If an I2C adapter doesn't match the provided device tree node, also try
matching the parent's device tree node. This allows finding an adapter
based on the device node of the parent device that was used to register
it.

This fixes a regression on Tegra124-based Chromebooks (Nyan) where the
eDP controller registers an I2C adapter that is used to read to EDID.
After commit 993a815d ("dt-bindings: panel: Add missing .txt
suffix") this stopped working because the I2C adapter could no longer
be found. The approach in this patch fixes the regression without
introducing the issues that the above commit solved.

Fixes: 17ab7806 ("drm: don't link DP aux i2c adapter to the hardware device node")
Signed-off-by: NThierry Reding <treding@nvidia.com>
Tested-by: NTristan Bastian <tristan-c.bastian@gmx.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This commit removes hard-coded bus timeout value setting so that
it can be set by i2c-core-base.
Signed-off-by: NJae Hyun Yoo <jae.hyun.yoo@linux.intel.com>
Reviewed-by: NJoel Stanley <joel@jms.id.au>
Reviewed-by: NBrendan Higgins <brendanhiggins@google.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Update copyright years and add Renesas to it. Add/update comments to
make driver easier to understand.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

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

In preparation to remove the do-while-loop.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

All state machines deal with pd->pos values. This helper function is an
exception and makes it only more confusing.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

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

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

pd->pos won't be smaller than -1, so we can simplify the logic.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

When doing s2idle/s2ram on Salvator-X(S):

    WARNING: CPU: 2 PID: 971 at drivers/i2c/i2c-core-base.c:1869 __i2c_transfer+0x608/0x910
[...]
    Call trace:
     __i2c_transfer+0x608/0x910
     i2c_smbus_xfer_emulated+0x158/0x5b0
     __i2c_smbus_xfer+0x17c/0x818
     i2c_smbus_xfer+0x64/0x98
     i2c_smbus_read_byte_data+0x40/0x70
     cs2000_bset.isra.1+0x2c/0x68
     __cs2000_set_rate.constprop.7+0x80/0x148
     cs2000_resume+0x18/0x20
     dpm_run_callback+0x74/0x330
     device_resume_early+0xd4/0x120
     dpm_resume_early+0x158/0x4f8
     suspend_devices_and_enter+0x36c/0xd98
[...]

On second resume, the sound driver fails with:

    cs2000-cp 2-004f: pll lock failed
    rcar_sound ec500000.sound: can't use clk 1

As the CS2000 clock driver needs to send I2C messages during suspend,
the I2C controller driver should be suspended later, and resumed
earlier.  Fix this by using the noirq sleep ops instead of the normal
sleep ops, which are called after the late sleep ops, as used by the
CS2000 clock driver.

Fixes: 18569fa8 ("i2c: rcar: add suspend/resume support")
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Change the call to PTR_ERR to access the value just tested by IS_ERR.

Fixes: 5b3a23a3 ("i2c: imx: notify about real errors on dma i2c_imx_dma_request")
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Reviewed-by: NOleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: NEsben Haabendal <esben@haabendal.dk>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

As discussed previously the best location for certain bus related bits,
e.g. I2C, is its own realm of the headers.

In order to uncontaminate acpi.h move the I2C bits to i2c.h.

There is no functional change intended.

Link: https://lkml.org/lkml/2018/11/28/744Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Improve the error handling in i2c_imx_dma_request() and let it return an error
indication that the caller then can handle accordingly.
Signed-off-by: NOleksij Rempel <o.rempel@pengutronix.de>
Acked-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

At least on i.MX5x, the DMA events for I2C and SDHC use the same channel
and there can only be a single user. So in this case there should be no
message emitted that looks like an error if the I2C device doesn't have
an assigned DMA channel. In contrast real problems that were only
emitted at debug level before should be described at a higher level
to be better visible and so understandable.
Signed-off-by: NOleksij Rempel <o.rempel@pengutronix.de>
Acked-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Because the adapter will be set up before every transaction anyhow, we
just need to mark it as suspended to the I2C core.
Signed-off-by: NHiromitsu Yamasaki <hiromitsu.yamasaki.ym@renesas.com>
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Rejecting transfers should be handled by the core. Also, this will
ensure proper locking which was forgotten in this open coded version.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Rejecting transfers should be handled by the core. Also, this will
ensure proper locking which was forgotten in this open coded version.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Rejecting transfers should be handled by the core.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: NBaolin Wang <baolin.wang@linaro.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The pointer to a device is usually named 'dev'. These 'pdev' here look
much like copy&paste errors. Fix them to avoid confusion.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: NBaolin Wang <baolin.wang@linaro.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Rejecting transfers should be handled by the core. Also, this will
ensure proper locking which was forgotten in this open coded version
and make sure resume mark is set after enabling clocks (not before).
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: NShawn Guo <shawnguo@kernel.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Rejecting transfers should be handled by the core.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: NKamal Dasu <kdasu.kdev@gmail.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This flag was defined and checked but never set a value. Remove it.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

A few drivers open code the handling of suspended adapters. It could be
handled by the core, though, to ensure generic handling. This patch adds
the flag and accessor functions. The usage of these helpers is optional,
though. See the kerneldoc in this patch. Using the new flag, we now
reject further transfers if the adapter is already marked suspended.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>