The first I2C slave provider using the new generic interface.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

The first user of the i2c-slave interface is an eeprom simulator. It is
a shared memory which can be accessed by the remote master via I2C and
locally via sysfs.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Finally(!), make Linux support being an I2C slave. Most of the existing
infrastructure is reused. We mainly add i2c_slave_register/unregister()
calls which tells i2c bus drivers to activate the slave mode. Then, they
also get a callback to report slave events to.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

So get_maintainer.pl will add us when something gets updated there.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

In (6468276b i2c: designware: make SCL and SDA falling time
configurable) new device tree properties were added for setting the
falling time of SDA and SCL.  The device tree bindings doc had a typo
in it: it forgot the "-ns" suffix for both properies in the prose of
the bindings.

I assume this is a typo because:
* The source code includes the "-ns"
* The example in the bindings includes the "-ns".

Fix the typo.
Signed-off-by: Doug Anderson <dianders@chromium.org>
Fixes: 6468276b ("i2c: designware: make SCL and SDA falling time configurable")
Acked-by: Romain Baeriswyl <romain.baeriswyl@alitech.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org

Switch Davinci I2C driver to use platform_get_irq(), because
it is not recommened to use platform_get_resource(pdev, IORESOURCE_IRQ, ..)
for requesting IRQ resources any more, as they can be not ready yet
in case of DT-boot.
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

New drivers should use PM ops instead of the legacy suspend/resume
callbacks. Update the I2C device driver guides to reflect this.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

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>

Add support for SCCB by implementing I2C_M_IGNORE_NAK and I2C_M_STOP
flags and advertising functionality flag I2C_FUNC_PROTOCOL_MANGLING.

Also fixed missing functionality flag I2C_FUNC_NOSTART.
Signed-off-by: Petr Cvek <petr.cvek@tul.cz>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Commit 0f5768bf ("i2c: omap: implement workaround for handling
invalid BB-bit values") introduce the error result in boot test fault on
OMAP3530 boards.

The patch fix the error (disable i2c bus test for OMAP3530).
Reported-by: Kevin Hilman <khilman@kernel.org>
Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Fixes: 0f5768bf ("i2c: omap: implement workaround for handling invalid BB-bit values")
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Let's handle i2c interrupt re-configuration in i2c driver. This will
help us in removing some soc specific checks from machine files and
will help in removing static iomapping of SYS register in exynos.c

Also handle saving and restoring of SYS_I2C_CFG register during
suspend and resume of i2c driver.
Signed-off-by: Pankaj Dubey <pankaj.dubey@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Now that we are using the clk notifier framework we get compile errors
without COMMON_CLK. But the driver fails to probe without COMMON_CLK
anyways, so just add that as a Kconfig dependency.
Signed-off-by: Max Schwarz <max.schwarz@online.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

No functional changes.
Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Arbitration Lost is an expected situation in a multimaster
environment. I2C controller (IP) correctly detect and report AL.

The only one visible reason for resetting IP in the AL case is
to avoid advisory 1.94 (omap3) and errata i595 (omap4): "I2C:
After an Arbitration is Lost the Module Incorrectly Starts
the Next Transfer".

Errata workaround states: "The MST and STT bits inside I2C_CON
should be set to 1 at the same moment (avoid setting the MST bit
to 1 while STT = 0)." The driver never set MST and STT bits
separately and doesn't create condition for errata. So the reset
is not necessary.

Also corrected return value for AL to -EAGAIN.

Tested on Beagleboard XM C.
Tested on BBB and AM437x Starter Kit by Felipe Balbi.
Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Tested-by: Felipe Balbi <balbi@ti.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

In a multimaster environment, after IP software reset, BB-bit value doesn't
correspond to the current bus state. It may happen what BB-bit will be 0,
while the bus is busy due to another I2C master activity.

Any transfer started when BB=0 and bus is busy wouldn't be completed by IP
and results in controller timeout. More over, in some cases IP could
interrupt another master's transfer and corrupt data on wire.

The commit implement method allowing to prevent IP from entering into
"controller timeout" state and from "data corruption" state.

The one drawback is the need to wait for 10ms before the first transfer.

Tested on Beagleboard XM C.
Tested on BBB and AM437x Starter Kit by Felipe Balbi.
Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Tested-by: Felipe Balbi <balbi@ti.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Delete STAT_AD0 mask as unrelated to current IP (omap1?).
Delete DEBUG conditional around SYSTEST masks group.
Add SYSTEST functional mode masks for SCL and SDA.
Add STAT_BF mask.
Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com>
Tested-by: Felipe Balbi <balbi@ti.com>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

The i2c input clock can change dynamically, e.g. on the RK3066 where
pclk_i2c0 and pclk_i2c1 are connected to the armclk, which changes
rate on cpu frequency scaling.

Until now, we incorrectly called clk_get_rate() while holding the
i2c->lock in rk3x_i2c_xfer() to adapt to clock rate changes.
Thanks to Huang Tao for reporting this issue.

Do it properly now using the clk notifier framework. The callback
logic was taken from i2c-cadence.c.

Also rename all misleading "i2c_rate" variables to "clk_rate", as they
describe the *input* clk rate.
Signed-off-by: Max Schwarz <max.schwarz@online.de>
Tested-by: Doug Anderson <dianders@chromium.org> on RK3288
Reviewed-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

If dma controller is not probed, defer i2c probe.
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Since at91sam9g45 is now DT-only, all DMA capable users of this driver
are using the DT case, and the legacy support can be removed.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

This allows checkpatch to validate more DTSes.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

This allows checkpatch to validate more DTSes.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

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>

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Yao Yuan <yao.yuan@freescale.com>

The SCB is present on IMG SoCs other than the META-based TZ1090,
such as the MIPS-based Pistachio SoC.  Relax the Kconfig dependency
so that it can be built on any MIPS or META machine.
Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Acked-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

This is a driver for the I2C controller found in Amlogic Meson SoCs.
Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

This makes the topology clearer. For instance, by adding a pca9547
device with address 0x70 to bus i2c-0, you get:

/sys/class/i2c-dev/i2c-0/device/0-0070/channel-0 -> i2c-1
...
/sys/class/i2c-dev/i2c-0/device/0-0070/channel-7 -> i2c-8
Signed-off-by: Gerlando Falauto <gerlando.falauto@keymile.com>
[wsa: simplified sysfs-usage and fixed format string usage]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Martin Belanger <martin.belanger@cyaninc.com>
Acked-by: Danielle Costantino <danielle.costantino@gmail.com>

The current implementation creates muxed i2c-<n> busses as immediate
children of their i2c-<n> parent bus. In case of multiple muxes on one
bus, it is impossible to determine which muxed bus comes from which mux.

It could be argued that the parent device should be changed from the
parent adapter to the mux device. This has pros and cons. To improve the
topology, simply add a "mux_device" symlink pointing to the actual
muxing device, so we can distinguish muxed busses. Doing it this way, we
don't break the ABI.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Tested-by: Guenter Roeck <linux@roeck-us.net>

No need to initialize 'ret' if it gets assigned directly after that.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>

Add dma support for i2c. This function depend on DMA driver.
You can turn on it by write both the dmas and dma-name properties in dts node.
DMA is optional, even DMA request unsuccessfully, i2c can also work well.
Signed-off-by: Yuan Yao <yao.yuan@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

If the inlcude headers aren't sorted alphabetically, then the
logical choice is to append new ones, however that creates a
lot of potential for conflicts or duplicates because every change
will then add new includes in the same location.
Signed-off-by: Yuan Yao <yao.yuan@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Since commit 2fd36c55 ("i2c: core: Map OF IRQ at probe time"),
i2c slaves without interrupts (e.g. da9210 and at24 on r8a7791/koelsch)
fail to probe:

    at24: probe of 2-0050 failed with error -22

    da9210: probe of 6-0068 failed with error -22

This happens because the call to of_irq_get() in i2c_device_probe()
returns -EINVAL.

If a device node does not have an "interrupts" property,
of_irq_parse_one() fails. Unlike irq_of_parse_and_map(), of_irq_get()
does not ignore errors from of_irq_parse_one(), but forwards them.

Make i2c_device_probe() ignore all errors but -EPROBE_DEFER to fix this,
just like platform_get_irq() and platform_get_irq_byname() already do.

Fixes: 2fd36c55 ("i2c: core: Map OF IRQ at probe time")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Add support for the IMG I2C Serial Control Bus (SCB) found on the
Pistachio and TZ1090 SoCs.
Reviewed-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
[Ezequiel: code cleaning and rebasing]
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Introduce a devicetree binding for Imagination Technologies
I2C SCB controller.
Reviewed-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

The driver tried to access device registers with the (little-endian)
iowrite/ioread functions. While this worked on little-endian machines
(e.g. Microblaze with AXI bus), it made the driver unusable on
big-endian machines (e.g. PPC405 with PLB).

During the probe function, the driver tried to write a 32-bit reset mask
into the reset register. This caused an error interrupt on big-endian
systems, because the device detected an invalid (byte-swapped) reset
mask. The result was an Oops.

The patch implements an endianness detection similar to the one used in
other Xilinx drivers like drivers/spi/spi-xilinx.c. It was tested on a
PPC405/PLB system.
Signed-off-by: Thomas Gessler <Thomas.Gessler@exp2.physik.uni-giessen.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

I have a at24 EEPROM connected via i2c bus provided by ISCH i2c
bus driver. This bus driver does not support
I2C_FUNC_SMBUS_WRITE_I2C_BLOCK and so I was looking for a way
to be able to write the eeprom. This patch adds support for
I2C_SMBUS_BYTE_DATA writing via i2c_smbus_write_byte_data.
It is quite slow, but it works.
Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
[wsa: s/use_smbuse_write/use_smbus_write/]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Signed-off-by: Devin Ryles <devin.ryles@intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

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>

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>

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>

Amend the at91 i2c pin controller to set the state of the pins to:
- "default" on resume.
- "sleep" on suspend().

This should make it possible to optimize energy usage for the pins
both for the suspend/resume cycle
Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>