This doc helps Linux users navigate through I2C sysfs and learn
the system I2C topology.
Signed-off-by: Alex Qiu <xqiu@google.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

If an i2c client receives an interrupt during reboot or shutdown it may
be too late to service it by making an i2c transaction on the bus
because the i2c controller has already been shutdown. This can lead to
system hangs if the i2c controller tries to make a transfer that is
doomed to fail because the access to the i2c pins is already shut down,
or an iommu translation has been torn down so i2c controller register
access doesn't work.

Let's simply disable the irq if there isn't a shutdown callback for an
i2c client when there is an irq associated with the device. This will
make sure that irqs don't come in later than the time that we can handle
it. We don't do this if the i2c client device already has a shutdown
callback because presumably they're doing the right thing and quieting
the device so irqs don't come in after the shutdown callback returns.
Reported-by: kernel test robot <lkp@intel.com>
[swboyd@chromium.org: Dropped newline, added commit text, added
interrupt.h for robot build error]
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Add a DT binding documentation for the MT8195 soc.
Signed-off-by: Kewei.Xu <kewei.xu@mediatek.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Fix the following warnings reported by checkpatch::
drivers/i2c/busses/i2c-imx.c:173: WARNING: Prefer 'unsigned int' to bare use of 'unsigned'
drivers/i2c/busses/i2c-imx.c:175: WARNING: Prefer 'unsigned int' to bare use of 'unsigned'
drivers/i2c/busses/i2c-imx.c:176: WARNING: Prefer 'unsigned int' to bare use of 'unsigned'
drivers/i2c/busses/i2c-imx.c:177: WARNING: Prefer 'unsigned int' to bare use of 'unsigned'
drivers/i2c/busses/i2c-imx.c:455: WARNING: Unnecessary ftrace-like logging - prefer using ftrace
drivers/i2c/busses/i2c-imx.c:602: WARNING: Unnecessary ftrace-like logging - prefer using ftrace
drivers/i2c/busses/i2c-imx.c:638: WARNING: Unnecessary ftrace-like logging - prefer using ftrace
drivers/i2c/busses/i2c-imx.c:1170: WARNING: Unnecessary ftrace-like logging - prefer using ftrace
drivers/i2c/busses/i2c-imx.c:1374: WARNING: Unnecessary ftrace-like logging - prefer using ftrace
drivers/i2c/busses/i2c-imx.c:1398: WARNING: Prefer strscpy over strlcpy - see: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/Signed-off-by: Kwon Tae-young <tykwon@m2i.co.kr>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Common pattern of handling deferred probe can be simplified with
dev_err_probe().  Less code and the error value gets printed.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Common pattern of handling deferred probe can be simplified with
dev_err_probe().  Less code and the error value gets printed.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Common pattern of handling deferred probe can be simplified with
dev_err_probe().  Less code and the error value gets printed.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

On Xilinx zynq SOC if the delay between address register write and
control register write in cdns_mrecv function is more, the xfer size
register rolls over and controller is stuck. This is an IP bug and
is resolved in later versions of IP.

To avoid this scenario, disable the interrupts on the current processor
core between the two register writes and enable them later. This can
help achieve the timing constraint.
Signed-off-by: Raviteja Narayanam <raviteja.narayanam@xilinx.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

The TI part is equivalent to the NXP part, and its compatible value is
not documented in the DT bindings.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

i801_setup_hstcfg() leaves the bits in priv->original_hstcfg that
we're interested in intact. Therefore we can remove the return value
from the function and use priv->original_hstcfg directly.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

We are the driver, so we can use the driver name directly instead of
retrieving it by calling dev_driver_string().
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Why shall we bother to open-code something that the compiler can do for us.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Polling uses the same timeout as irq mode: 400 * 500us = 200ms = HZ / 5.
So let's use the adapter->timeout value also for polling. This has the
advantage that userspace can control the timeout value for polling as
well. In addition change the code to make it better readable.
Last but not least remove the timeout debug messages. Calls to both
functions are followed by a call to i801_check_post() that will print
an error message in case of timeout.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

The driver is run on the platforms where OF node is always NULL.
The confusion comes from IRQ domain APIs that take either OF or
firmware node as input parameter. Since fwnode is not used here
either, replace of_node by NULL.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

RZ/G2L i2c controller is compatible with RZ/A i2c controller.
By default IP is in reset state, so need to perform release
reset before accessing any register.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Document RZ/G2L I2C controller bindings.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Convert the Renesas R-Mobile I2C Bus Interface (IIC) Device Tree binding
documentation to json-schema.

Document missing properties.
R-Mobile A1 and SH-Mobile have multiple interrupts.
Update the example to match reality.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

According to the Hardware User's Manual, automatic transmission for PMIC
control (DVFS) is not available on the R-Car E3 and RZ/G2E SoC.
Experiments showed this really means that support for automatic DVFS is
not present, while the IIC automatic transmission feature itself is
still available, albeit not super useful.

Hence there is no longer a reason not to declare compatibility with the
R-Car Gen3-specific and generic versions, and the corresponding
paragraph can be dropped.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

The "reset-active-low" property was removed from the ssd1307fb bindings
in commit 519b4dba ("fbdev: ssd1307fb: Remove reset-active-low
from the DT binding document") and from the ssd1307fb binding examples
in commit 7d7e58d3 ("dt-bindings: display: ssd1307fb: Remove
reset-active-low from examples").
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Convert i2c-omap.txt to YAML schema for better checks and documentation.

Following properties were used in DT but were not documented in txt
bindings and has been included in YAML schema:
1. Include ti,am4372-i2c compatible
2. Document clocks property
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

The people on linux-renesas-soc are interested in changes to the Renesas
I2C drivers and their DT bindings.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Add vbus-supply which provides power to SCL/SDA. Pass this regulator
into core so it can be turned on/off for low power mode support.
Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Reviewed-by: Qii Wang <qii.wang@mediatek.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Add vbus-supply property for mt65xx. The regulator can be passed into
core and turned off during suspend/sleep to reduce power consumption.
Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Although in the most platforms, the bus power of i2c
are alway on, some platforms disable the i2c bus power
in order to meet low power request.

We can control bulk regulator if it is provided in i2c
adapter device.
Signed-off-by: Bibby Hsieh <bibby.hsieh@mediatek.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

One may notice that dev_printk(KERN_DEBUG ...) is *not* an equivalent
to dev_dbg(). It will be printed whenever loglevel is high enough.
And currently it will be the only message in the I²C core in some
configurations that got printed under above conditions.

Moving to dev_dbg() will hide it in the configurations where Dynamic Debug
is enabled and hence align with all other debug messages in the I²C core..
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Convert the Renesas RZ/A I2C Bus Interface (RIIC) Device Tree binding
documentation to json-schema.

Document missing properties.
Update the example to match reality.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Convert the Renesas EMMA Mobile EV2 IIC Interface (IIC) Device Tree
binding documentation to json-schema.

Document missing properties.
Update the example to match reality.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Convert the Renesas R-Car I2C Controller Device Tree binding
documentation to json-schema.

Document missing properties.
Make the clocks property required.
DMA is supported on R-Car Gen3 and RZ/G2 only.
Update the example to match reality.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

The compatible value "renesas,i2c-rcar" was deprecated in commit
ad4a8dc3 ("i2c: rcar: Add per-Generation fallback bindings"),
and never had any users in upstream Linux.  Drop its description from
the DT bindings.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

The compatible value "renesas,i2c-rcar" was deprecated in commit
ad4a8dc3 ("i2c: rcar: Add per-Generation fallback bindings"),
and never had any users in upstream Linux.  Drop its match entry from
the driver.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Rename i2c irq name with dev_name() which can provide unique
naming in /proc/interrupts for each instance of the I2C IP core.
Signed-off-by: Qii Wang <qii.wang@mediatek.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Layout of these registers is part of the PCI standard. Therefore use
the constants defined by the PCI subsystem.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Using the completion API is more intuitive and it allows to simplify
the code. Note that we don't have to set priv->status = 0 any longer
with the completion API.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

When passing -ETIMEDOUT to i801_check_post() it will emit a timeout
error message. I don't see much benefit in an additional warning
stating more or less the same.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

The ast25xx and ast26xx have, respectively, two and three configurable
slave device addresses to the ast24xx's one.  We only support using
one at a time, but the others may come up in an indeterminate state
depending on hardware/bootloader behavior, so we need to make sure we
disable them so as to avoid ending up with phantom devices on the bus.
Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Tested-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Add support for the SMBus-Alert protocol to the STM32F7 that has
dedicated control and status logic.

If SMBus-Alert is used, the SMBALERT# pin must be configured as alternate
function for I2C Alert.
Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@foss.st.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

Since SMBus-Alert is an optional feature of SMBUS which
requires an additional pin, the smbus binding cannot be
used to indicate its support.

Add an additional smbus-alert binding specific for it and
update the description text of smbus to avoid mentioning
SMBus-Alert
Signed-off-by: Alain Volmat <alain.volmat@foss.st.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

SM8250 CCI is the same as SDM845, add an equivalent compatible for SM8250.
Signed-off-by: Jonathan Marek <jonathan@marek.ca>
Reviewed-by: Loic Poulain <loic.poulain@linaro.org>
Reviewed-by: Vinod Koul <vkoul@kernel.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

add "rockchip,rk3568-i2c", "rockchip,rk3399-i2c" for i2c nodes on
a rk3568 platform to i2c-rk3x.yaml.
Signed-off-by: Liang Chen <cl@rock-chips.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>