This patch adds support for the Analog Devices / Linear Technology
LTC4306 and LTC4305 4/2 Channel I2C Bus Multiplexer/Switches.
The LTC4306 optionally provides two general purpose input/output pins
(GPIOs) that can be configured as logic inputs, opendrain outputs or
push-pull outputs via the generic GPIOLIB framework.
Signed-off-by: NMichael Hennerich <michael.hennerich@analog.com>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NPeter Rosin <peda@axentia.se>

i2c_mux_add_adapter already logs a message on failure.
Reviewed-by: NWolfram Sang <wsa@the-dreams.de>
Signed-off-by: NPeter Rosin <peda@axentia.se>

i2c_mux_add_adapter already logs a message on failure.
Reviewed-by: NWolfram Sang <wsa@the-dreams.de>
Signed-off-by: NPeter Rosin <peda@axentia.se>

i2c_mux_add_adapter already logs a message on failure.
Reviewed-by: NWolfram Sang <wsa@the-dreams.de>
Signed-off-by: NPeter Rosin <peda@axentia.se>

i2c_mux_add_adapter already logs a message on failure.
Reviewed-by: NWolfram Sang <wsa@the-dreams.de>
Signed-off-by: NPeter Rosin <peda@axentia.se>

i2c_mux_add_adapter already logs a message on failure.
Reviewed-by: NWolfram Sang <wsa@the-dreams.de>
Signed-off-by: NPeter Rosin <peda@axentia.se>

i2c_mux_add_adapter already logs a message on failure.
Reviewed-by: NWolfram Sang <wsa@the-dreams.de>
Signed-off-by: NPeter Rosin <peda@axentia.se>

No callers then need to report any further info, thus reducing both the
amount of code and the log noise.
Reviewed-by: NWolfram Sang <wsa@the-dreams.de>
Signed-off-by: NPeter Rosin <peda@axentia.se>

The pca954x i2c mux driver currently implements an irq_chip for handling
interrupts; due to how irq_chip handling is done, it's necessary for the
irq_chip methods to be invoked from hardirq context, even on a a
real-time kernel.  Because the spinlock_t type becomes a "sleeping"
spinlock w/ RT kernels, it is not suitable to be used with irq_chips.

A quick audit of the operations under the lock reveal that they do only
minimal, bounded work, and are therefore safe to do under a raw spinlock.
Signed-off-by: NJulia Cartwright <julia@ni.com>
Signed-off-by: NPeter Rosin <peda@axentia.se>

This reverts commit b0c1e95a. It
contains a flaw and the next version has more features added which makes
me want to move it to the next cycle.
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This reverts commit 02dbfa5e. I grabbed
the wrong version from the list and will pull the proper one from Peter
Rosin's mux tree.
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

After commit 7999eecb ("i2c: exynos5: fix arbitration lost handling"),
some I2C transactions are failing because the TRANSFER_DONE_AUTO field is
not set in the I2C_TRANS_STATUS register so the i2c->status value is left
to -EINVAL causing the i2c->msg_complete completion to never be signaled.

For example, when reading the time of an I2C rtc on an Exynos5800 machine:

$ cat /sys/class/rtc/rtc0/time
[   25.924594] exynos5-hsi2c 12e10000.i2c: rx timeout
[   65.028365] max77686-rtc max77802-rtc: Fail to read time reg(-22)
cat: /sys/class/rtc/rtc0/time: Invalid argument

The Exynos5422 manual states clearly that most I2C_TRANS_STATUS reg bits
(including TRANSFER_DONE_AUTO) are cleared after the register is read. So
reading has side effects and should only be done if HSI2C_INT_I2C was set.

Fixes: 7999eecb ("i2c: exynos5: fix arbitration lost handling")
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Reviewed-by: NAndrzej Hajda <a.hajda@samsung.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Some platforms like hi3660 need do reset first to allow accessing registers
Signed-off-by: NZhangfei Gao <zhangfei.gao@linaro.org>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: NRamiro Oliveira <ramiro.oliveira@synopsys.com>
Acked-by: NJarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Most likely a copy & paste error.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Acked-by: NJerome Brunet <jbrunet@baylibre.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Fixes: 30021e37 ("i2c: add support for Amlogic Meson I2C controller")

This will allow marking device property lists as __initdata, the same as
board info structures themselves.
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

All length fields in Linux I2C are u16, so a HW length limitation of 16
bit lengths is not a limitation. Remove the quirk structure.
Tested-by: NJun Gao <jun.gao@mediatek.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The BSC data buffers to send and receive data are each of size 32 bytes
or 8 bytes 'xfersz' depending on SoC. The problem observed for all the
combined message transfer was if length of data transfer was a multiple
of 'xfersz' a repeated START was being transmitted by BSC driver. Fixed
this by appropriately setting START/STOP conditions for such transfers.

Fixes: dd1aa252 ("i2c: brcmstb: Add Broadcom settop SoC i2c controller driver")
Signed-off-by: NJaedon Shin <jaedon.shin@gmail.com>
Acked-by: NKamal Dasu <kdasu.kdev@gmail.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Refcount of of_node is increased with of_node_get() in i2c_mux_add_adapter().
It must be decreased with of_node_put() in i2c_mux_del_adapters().
Signe-off-by: NQi Hou <qi.hou@windriver.com>
Reviewed-by: NZhang Xiao <xiao.zhang@windriver.com>
Acked-by: NPeter Rosin <peda@axentia.se>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

While modifying the driver to use the STOP interrupt, the completion of the
intermediate transfers need to wake the driver back up in order to initiate
the next transfer (restart condition). Otherwise you get never ending
interrupts and only the first transfer sent.

Fixes: 71ccea09 ("i2c: riic: correctly finish transfers")
Reported-by: NSimon Horman <horms@verge.net.au>
Signed-off-by: NChris Brandt <chris.brandt@renesas.com>
Tested-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Refcount of of_node is increased with of_node_get() in i2c_mux_add_adapter().
It must be decreased with of_node_put() in i2c_mux_del_adapters().

Cc: stable@vger.kernel.org
Signed-off-by: NQi Hou <qi.hou@windriver.com>
Reviewed-by: NZhang Xiao <xiao.zhang@windriver.com>
Signed-off-by: NPeter Rosin <peda@axentia.se>

sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>

Fix up affected files that include this signal functionality via sched.h.
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NIngo Molnar <mingo@kernel.org>

Using pci_alloc_irq_vectors() instead of the deprecated
pci_enable_msix() allows to remove the msix_entry from
struct octeon_i2c and thus to get rid of the config symbol check.
Signed-off-by: NJan Glauber <jglauber@cavium.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

In case of arbitration lost adequate interrupt sometimes is not signaled.
As a result transfer timeouts and is not retried, as it should. To avoid
such cases code is added to check transaction status in case of every
interrupt.
Signed-off-by: NAndrzej Hajda <a.hajda@samsung.com>
Tested-by: NAndi Shyti <andi.shyti@samsung.com>
Reviewed-by: NAndi Shyti <andi.shyti@samsung.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Fifo-almost-empty irq signal should be disabled as soon as possible,
to avoid unnecessary interrupt storm. The best moment is when there is
no more data to feed fifo.
This patch fixes system stalls caused by IRQ storm.
Signed-off-by: NAndrzej Hajda <a.hajda@samsung.com>
Tested-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Tested-by: NAndi Shyti <andi.shyti@samsung.com>
Reviewed-by: NAndi Shyti <andi.shyti@samsung.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

When going to suspend, the I2C registers may be lost because the power to
VDDcore is cut. Restore them when resuming.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: NLudovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Since commit e2474541 ("bcm2835: Fix hang for writing messages
larger than 16 bytes") the interrupt handler is prone to a possible
NULL pointer dereference. This could happen if an interrupt fires
before curr_msg is set by bcm2835_i2c_xfer_msg() and randomly occurs
on the RPi 3. Even this is an unexpected behavior the driver must
handle that with an error instead of a crash.
Reported-by: NPeter Robinson <pbrobinson@gmail.com>
Fixes: e2474541 ("bcm2835: Fix hang for writing messages larger than 16 bytes")
Signed-off-by: NStefan Wahren <stefan.wahren@i2se.com>
Acked-by: NNoralf Trønnes <noralf@tronnes.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Add Tegra BPMP I2C driver. The BPMP is the boot and power management
processor embedded in Tegra SoCs. In newer SoC versions, access to one
of the I2C busses goes via the BPMP, requiring a different "proxy" I2C
driver that accesses the bus via the real I2C driver embedded in the
BPMP firmware.
Signed-off-by: NShardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: NThierry Reding <treding@nvidia.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This reverts commit 63d0f0a6.

It caused a regression on platforms where I2C controller is synthesized
with dynamic TAR update disabled. Detection code is testing is bit
DW_IC_CON_10BITADDR_MASTER in register DW_IC_CON read-only but fails to
restore original value in case bit is read-write.

Instead of fixing this we revert the commit since it was preparation for
the commit 0317e6c0 ("i2c: designware: do not disable adapter after
transfer") which was also reverted.
Reported-by: NShah Nehal-Bakulchandra <Nehal-bakulchandra.Shah@amd.com>
Reported-by: NSuravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Acked-By: NLucas De Marchi <lucas.demarchi@intel.com>
Cc: <stable@vger.kernel.org> # v4.9+
Fixes: 63d0f0a6 ("i2c: designware: detect when dynamic tar update is possible")
Signed-off-by: NJarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Various muxes can aggregate multiple interrupts from each i2c bus.
All of the muxes with interrupt support combine the active low irq lines
using an internal 'and' function and generate a combined active low
output. The muxes do provide the ability to read a control register to
determine which irq is active. By making the mux an irq controller isr
latency can potentially be reduced by reading the status register and
then only calling the registered isr on that bus segment.

As there is no irq masking on the mux irq are disabled until irq_unmask is
called at least once.
Signed-off-by: NPhil Reid <preid@electromag.com.au>
Signed-off-by: NPeter Rosin <peda@axentia.se>

The spec for the pca954x was missing. This chip is the same as the pca9540
except that it has interrupt lines. While the i2c_device_id table mapped
the pca9542 to the pca9540 definition the compatible table did not. In
preparation for irq support add the pca9542 definition.
Signed-off-by: NPhil Reid <preid@electromag.com.au>
Signed-off-by: NPeter Rosin <peda@axentia.se>

This fixes the condition where the controller has not fully completed its
final transfer and leaves the bus and controller in a undesirable state.

At the end of the last transmitted byte, the existing driver would just
signal for a STOP condition to be transmitted then immediately signal
completion. However, the full STOP procedure might not have fully taken
place by the time the runtime PM shuts off the peripheral clock, leaving
the bus in a suspended state.

Alternatively, the STOP condition on the bus may have completed, but when
the next transaction is requested by the upper layer, not all the
necessary register cleanup was finished from the last transfer which made
the driver return BUS BUSY when it really wasn't.

This patch now makes all transmit and receive transactions wait for the
STOP condition to fully complete before signaling a completed transaction.
With this new method, runtime PM no longer seems to be an issue.

Fixes: 310c18a4 ("i2c: riic: add driver")
Signed-off-by: NChris Brandt <chris.brandt@renesas.com>
Reviewed-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Intel Gemini Lake has the same SMBus host controller than Intel Broxton.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The I2C core always reports a MODALIAS of the form i2c:<foo> even if the
device was registered via OF, this means that exporting the OF device ID
table device aliases in the module is not needed. But in order to change
how the core reports modaliases to user-space, it's better to export it.
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Acked-by: NPeter Rosin <peda@axentia.se>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

The I2C core always reports a MODALIAS of the form i2c:<foo> even if the
device was registered via OF, this means that exporting the OF device ID
table device aliases in the module is not needed. But in order to change
how the core reports modaliases to user-space, it's better to export it.
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Acked-by: NPeter Rosin <peda@axentia.se>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Remove including <linux/version.h> that don't need it.
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Acked-by: NVadim Pasternak <vadimp@mellanox.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

SMBSLVCNT must be protected with the piix4_mutex_sb800 in order to avoid
multiple buses accessing to the semaphore at the same time.

Fixes: 701dc207 ("i2c: piix4: Avoid race conditions with IMC")
Reported-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NRicardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Since '701dc207 ("i2c: piix4: Avoid race conditions with IMC")' we
are using the SMBSLVCNT register at offset 0x8. We need to request it.

Fixes: 701dc207 ("i2c: piix4: Avoid race conditions with IMC")
Signed-off-by: NRicardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: NJean Delvare <jdelvare@suse.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

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: NBhumika Goyal <bhumirks@gmail.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> for
Acked-by: NPatrice Chotard <patrice.chotard@st.com>
Acked-by: NJarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: NJean Delvare <jdelvare@suse.de>
Acked-by: NLudovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

With many drivers converting to using generic device properties, it is
useful to provide array of device properties when instantiating new i2c
client via i2c_board_info and have them automatically added to the device
in question.
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: NWolfram Sang <wsa@the-dreams.de>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

When using devicetree i2c_board_info.type is set to the compatible
string with the vendor prefix removed. For I2C devices described via
ACPI the i2c_board_info.type string is set to the ACPI device name. When
using ACPI and DT ids this string ends up something like "PRP0001:00".

If the of_compatible property is present try to use that instead. This
makes it easier to instantiate i2c drivers through ACPI with DT ids.
Signed-off-by: NDan O'Donovan <dan@emutex.com>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: NJarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: NJarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: NWolfram Sang <wsa@the-dreams.de>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>