Use the new callback to reject atomic transfers.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

The driver already has the routine in place, tie it to the new callback.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

By properly setting up the algorithm at probe time, we can skip the
check at every transfer. This allows us to get rid of the flags
completely.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Acked-by: Peter Korsgaard <peter@korsgaard.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

The driver did handle this internally, convert it to use the new
callbacks.
Reviewed-by: Timo Alho <talho@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Add the master_xfer_atomic hook to enable i2c transactions in irq
disabled contexts like the poweroff case.
Signed-off-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Keerthy <j-keerthy@ti.com>
[wsa: simplified code a little: 'timeout = !ret']
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

If the parent has an atomic callback, we need to translate it the same
way as the non-atomic callback.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

If the parent adapter has atomic_xfer callbacks, populate them for the
mux adapter as well. We can use the same translation function as for the
non-atomic xfer callback.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Peter Rosin <peda@axentia.se>
Reviewed-by Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

We had the request to access devices very late when interrupts are not
available anymore multiple times now. Mostly to prepare shutdown or
reboot. Allow adapters to specify a specific callback for this case.
Note that we fall back to the generic {master|smbus}_xfer callback if
this new atomic one is not present. This is intentional to preserve the
previous behaviour and avoid regressions. Because there are drivers not
using interrupts or because it might have worked "accidently" before.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Stefan Lengfeld <contact@stefanchrist.eu>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

If I2C transfers are executed in atomic contexts, trylock is used
instead of lock. This behaviour was missing for SMBUS, although a lot of
transfers are of SMBUS type, either emulated or direct. So, factor out
the locking routine into a helper and use it for I2C and SMBUS.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Commit cea443a8 ("i2c: Support i2c_transfer in atomic contexts")
added in_atomic() to the I2C core. However, the use of in_atomic()
outside of core kernel code is discouraged and was already[1] when this
code was added in early 2008. The above commit was a preparation for
commit b7a36701 ("i2c-pxa: Add polling transfer"). Its commit
message says explicitly it was added "for cases where I2C transactions
have to occur at times interrup[t]s are disabled". So, the intention was
'disabled interrupts'. This matches the use cases for atomic I2C
transfers I have seen so far: very late communication (mostly to a PMIC)
to powerdown or reboot the system. For those cases, interrupts are
disabled then. It doesn't seem that in_atomic() adds value.

After a discussion with Peter Zijlstra[2], we came up with a better set
of conditionals to match the use case.

The I2C core will soon gain an extra callback into bus drivers
especially for atomic transfers to make them more generic. The code
deciding which transfer to use (atomic/non-atomic) should mimic the
behaviour which locking to use (trylock/lock). This is why we add a
helper for it.

[1] https://lwn.net/Articles/274695/
[2] http://patchwork.ozlabs.org/patch/1067437/Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Stefan Lengfeld <contact@stefanchrist.eu>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

No further occurences in the driver.

Fixes: dd1aa252 ("i2c: brcmstb: Add Broadcom settop SoC i2c controller driver")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Add i2c compatible for MT8183. Compare to MT2712 i2c controller,
MT8183 has different register offsets. Ltiming_reg is added to
adjust low width of SCL. Arb clock and dma_sync are needed.
Signed-off-by: Qii Wang <qii.wang@mediatek.com>
Reviewed-by: Nicolas Boichat <drinkcat@chromium.org>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

When i2c and apdma use different source clocks, we should enable
synchronization between them.
Signed-off-by: Qii Wang <qii.wang@mediatek.com>
Reviewed-by: Nicolas Boichat <drinkcat@chromium.org>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

When two i2c controllers are internally connected to the same
GPIO pins, the arb clock is needed to ensure that the waveforms
do not interfere with each other. And we also need to enable
the interrupt to find arb lost, old i2c controllers also have
the bit.
Signed-off-by: Qii Wang <qii.wang@mediatek.com>
Reviewed-by: Nicolas Boichat <drinkcat@chromium.org>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Add MT8183 i2c binding to binding file. Compare to MT2712 i2c
controller, MT8183 has different registers, offsets, and clock.
Signed-off-by: Qii Wang <qii.wang@mediatek.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

New i2c registers would have different offsets, so we use different
offsets array to distinguish different i2c registers version.
Signed-off-by: Qii Wang <qii.wang@mediatek.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Commit 54fb4a05 ("i2c: Check for ACPI resource conflicts") included
<linux/acpi.h> so we could use acpi_check_region(). Commit fd46a006
("i2c: convert i2c-isch to platform_device") removed the use of
acpi_check_region() but not the include.

Remove the now-unnecessary include of <linux/acpi.h>.  No functional change
intended.

Fixes: fd46a006 ("i2c: convert i2c-isch to platform_device")
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

"res" can't be NULL because it's a pointer to somewhere in the middle of
the "adev" struct.  Also probe() succeeded so there is no need to check
here.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Add NIC I2C support to the iProc I2C driver. Access to the NIC I2C base
registers requires going through the IDM wrapper to map into the NIC's
address space
Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com>
Signed-off-by: Ray Jui <ray.jui@broadcom.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Update iProc I2C binding document to add new compatible string
"brcm,iproc-nic-i2c". Optional property "brcm,ape-hsls-addr-mask" is
also added that allows configuration of the host view into the APE's
address for "brcm,iproc-nic-i2c"
Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com>
Signed-off-by: Ray Jui <ray.jui@broadcom.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Use the following wrapper for read/write access of iProc i2c registers:
u32 iproc_i2c_rd_reg(struct bcm_iproc_i2c_dev *iproc_i2c,
                     u32 offset)
void iproc_i2c_wr_reg(struct bcm_iproc_i2c_dev *iproc_i2c, u32 offset,
                      u32 val)

This preps the driver for support of indirect register access required
by certain SoCs with this iProc I2C block integrated
Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com>
Signed-off-by: Ray Jui <ray.jui@broadcom.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Add polling support to the iProc I2C driver. Polling mode is
activated when the driver fails to obtain an interrupt ID from device
tree
Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com>
Signed-off-by: Ray Jui <ray.jui@broadcom.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Update the binding document to make the 'interrupts' property optional.
For certain revisions of the I2C controller (e.g., iProc NIC I2C), I2C
interrupt is unwired to the interrupt controller. In such case, this
'interrupts' property should be left unspecified, and driver will fall
back to polling mode
Signed-off-by: Ray Jui <ray.jui@broadcom.com>
Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Add support for more master error status including FIFO underrun and RX
FIFO full
Signed-off-by: Michael Cheng <ccheng@broadcom.com>
Signed-off-by: Ray Jui <ray.jui@broadcom.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Add slave mode support to the iProc I2C driver.
Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com>
Signed-off-by: Michael Cheng <ccheng@broadcom.com>
Signed-off-by: Shreesha Rajashekar <shreesha.rajashekar@broadcom.com>
Signed-off-by: Ray Jui <ray.jui@broadcom.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Add support to allow I2C master read transfer up to 255 bytes.
Signed-off-by: Shreesha Rajashekar <shreesha@broadcom.com>
Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com>
Signed-off-by: Ray Jui <ray.jui@broadcom.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

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

Instead of using custom variables and parser, convert the driver to use
the ones provided by I2C core.

No functional change intended.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

MP2 controllers have two separate busses, so may accommodate up to two I2C
adapters. Those adapters are listed in the ACPI namespace with the
"AMDI0011" HID, and probed by a platform driver.

Communication with the MP2 takes place through MMIO registers, or through
DMA for more than 32 bytes transfers.

This is major rework of the patch submitted by Nehal-bakulchandra Shah from
AMD (https://patchwork.kernel.org/patch/10597369/).

Most of the event handling of v3 was rewritten to make it work with more
than one bus (e.g on Ryzen-based Lenovo Yoga 530), and this version
contains many other improvements.
Signed-off-by: Elie Morisse <syniurge@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Add STM32H7 and STM32MP1 in the list of compatible socs for each
optional property.
Signed-off-by: Bich Hemon <bich.hemon@st.com>
Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Remove extra spaces before colons.
Signed-off-by: Bich Hemon <bich.hemon@st.com>
Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Slave mode driver is based on the concept of i2c-designware driver.
Signed-off-by: Juergen Fitschen <me@jue.yt>
[ludovic.desroches@microchip.com: rework Kconfig and replace IS_ENABLED
by defined]
Signed-off-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

The single file i2c-at91.c has been split into core code (i2c-at91-core.c)
and master mode specific code (i2c-at91-master.c). This should enhance
maintainability and reduce ifdeffery for slave mode related code.

The code itself hasn't been touched. Shared functions only had to be made
non-static. Furthermore, includes have been cleaned up.
Signed-off-by: Juergen Fitschen <me@jue.yt>
[ludovic.desroches@microchip.com: fix checkpatch errors and use SPDX]
Signed-off-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

In order to implement slave mode support for the at91 hardware we have to
segregate all master mode specific function parts from the general parts.
The upcoming slave mode patch will call its sepcific probe resp. init
function instead of the master mode functions after the shared general
code has been executed.

This concept has been influenced by the i2c-designware driver.
Signed-off-by: Juergen Fitschen <me@jue.yt>
Signed-off-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

When sending with DMA, the driver transfers the first byte with PIO (as
documented). However, it started DMA right after the first byte was
written. This worked, but was not according to the datasheet which
suggests to wait until data register was empty again. Implement this.
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>

We will need to know if enabling DMA was successful in a later patch.
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>

Use a macro for the hardcoded value and apply a build check. If it is
not met, the driver logic will not work anymore.
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>

This avoids useless loops inside the I2C timing algorithm.
Actually, we support only one possible solution per prescaler value.
So after finding a solution with a prescaler, the algorithm can
switch directly to the next prescaler value.
Signed-off-by: Nicolas Le Bayon <nicolas.le.bayon@st.com>
Signed-off-by: Bich Hemon <bich.hemon@st.com>
Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

The Synopsys I2C Controller has an interface clock, but most SoCs hide
this away. However, on some SoCs you need to explicitly enable the
interface clock in order to access the registers. Therefore, add
support for an optional interface clock.
Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Signed-off-by: Gareth Williams <gareth.williams.jx@renesas.com>
Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

The driver requires an undocumented clock property, so detail it.
Add documentation for a separate, optional, interface clock.
Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Signed-off-by: Gareth Williams <gareth.williams.jx@renesas.com>
Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>