The behaviour, by default, to not deselect after each transfer is
unsafe when there is a device with an address that conflicts with
another device on another mux on the same parent bus, and it
may not be convenient to use devicetree to set the deselect mux,
e.g. when running on x86_64 when ACPI is used to discover most of the
device hierarchy.
Therefore, provide the ability to set the idle state behaviour using a
new sysfs file, idle_state as a complement to the method of
instantiating the device via sysfs. The possible behaviours are
disconnect, i.e. to deselect all channels from the mux, as-is (the
default), i.e. leave the last channel selected, and set a
predetermined channel.
The current behaviour of leaving the channel as-is after each
transaction is preserved.
Signed-off-by: Robert Shearman <robert.shearman@att.com>
Signed-off-by: Peter Rosin <peda@axentia.se>
There are no in-tree users of the pca954x platform data and the
per-channel deselect configuration complicates efforts to export the
configuration to user-space in a way that could be applied to other
muxes. Therefore, remove support for the pca954x platform data.
Signed-off-by: Robert Shearman <robert.shearman@att.com>
Signed-off-by: Peter Rosin <peda@axentia.se>
struct i2c_client has a direct pointer to the adapter, no need to dig
it out of the struct device tree.
Signed-off-by: Luca Ceresoli <luca@lucaceresoli.net>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Peter Rosin <peda@axentia.se>
This creates a struct device *dev helper variable in probe()
which IMO makes the code less cluttered and easier to read.
Also rename the of_node veriable to the common shortform "np"
(node pointer).
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
[peda: slightly edited commit message and removed some surplus newlines]
Signed-off-by: Peter Rosin <peda@axentia.se>
This simplifies the code, and you get retries for free if the adapter
does not support ->master_xfer.
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Drop call to of_match_device, which is subsumed by the subsequent
call to of_device_get_match_data. The code becomes simpler, and a
temporary variable can be dropped.
The semantic match that makes this change is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@r@
local idexpression match;
identifier i;
expression x, dev, e, e1;
@@
- match@i = of_match_device(x, dev);
- if (match) e = of_device_get_match_data(dev);
- else e = e1;
+ e = of_device_get_match_data(dev);
+ if (!e) e = e1;
@@
identifier r.i;
@@
- const struct of_device_id *i;
... when != i
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Peter Rosin <peda@axentia.se>
Instead of just hogging the reset GPIO into deactivated state, activate and
then de-activate the reset. This allows for better recovery if the CPU was
reset halfway through an I2C transaction for example.
Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
Signed-off-by: Peter Rosin <peda@axentia.se>
Make sure to not disallow the chips on adapters that are not capable
of reading the device id, but also make sure to check the device id
before writing to the chip.
Tested-by: Adrian Fiergolski <adrian.fiergolski@cern.ch>
Signed-off-by: Peter Rosin <peda@axentia.se>
This patch extends the current i2c-mux-pca954x driver and adds support for
a newer PCA984x family of the I2C switches and multiplexers from NXP.
Signed-off-by: Adrian Fiergolski <adrian.fiergolski@cern.ch>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
irq_create_mapping can return an error, report error to log and return.
Cleanup will occur in the probe function when an error is returned.
Suggested-by: Peter Rosin <peda@axentia.se>
Acked-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The pca954x device do not have the ability to mask interrupts. For
i2c slave devices that also don't have masking ability (eg ltc1760
smbalert output) delay registering the irq until after the mux
segments have been configured. During the mux add_adaptor call the
core i2c system can register an smbalert handler which would then
be called immediately when the irq is registered. This smbalert
handler will then clear the pending irq.
This removes the need for the irq_mask / irq_unmask calls that were
original used to do this.
Signed-off-by: Phil Reid <preid@electromag.com.au>
Acked-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
include/linux/i2c is not for client devices. Move the header file to a
more appropriate location.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Peter Rosin <peda@axentia.se>
Pull i2c updates from Wilfram Sang:
"I2C has the following updates for you:
- an immutable cross-subsystem branch fixing PMIC access on Intel
Baytrail
- bigger driver updates to the designware, meson, exynos5 drivers
- new i2c_acpi_new_device() function to create devices from ACPI
- struct i2c_driver has now a flag 'disable_i2c_core_irq_mapping' to
allow custom IRQ mapping in case the default does not fit
- mux subsystem centralized error messages in its core
- new driver for ltc4306 i2c mux
- usual set of small updates"
* 'i2c/for-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (44 commits)
i2c: thunderx: Enable HWMON class probing
i2c: rcar: clarify PM handling with more comments
i2c: rcar: fix resume by always initializing registers before transfer
i2c: tegra: fix spelling mistake: "contoller" -> "controller"
i2c: exynos5: use core helper to get driver data
i2c: exynos5: de-duplicate error logs on clock setup
i2c: exynos5: simplify clock frequency handling
i2c: exynos5: simplify timings calculation
i2c: designware-baytrail: fix potential null pointer dereference on dev
i2c: designware: Get selected speed mode sda-hold-time via ACPI
[media] cx231xx: stop double error reporting
i2c: core: Allow drivers to disable i2c-core irq mapping
i2c: core: Add new i2c_acpi_new_device helper function
i2c: core: Allow getting ACPI info by index
i2c: img-scb: use setup_timer
i2c: i2c-scmi: add a MS HID
i2c: mux: ltc4306: LTC4306 and LTC4305 I2C multiplexer/switch
dt-bindings: i2c: mux: ltc4306: Add dt-bindings for I2C multiplexer/switch
i2c: mux: reg: stop double error reporting
i2c: mux: pinctrl: stop double error reporting
...
The spec for the pca9546 was missing. This chip is the same as the pca9545
except that it lacks interrupt lines. While the i2c_device_id table mapped
the pca9546 to the pca9545 definition the compatible table did not.
Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
Signed-off-by: Peter Rosin <peda@axentia.se>
In ACPI world any ID should be carefully chosen and registered
officially. The commit bbf9d262a1 seems did a wrong assumption because
PCA is the registered PNP ID for "PHILIPS BU ADD ON CARD". I'm pretty
sure this prefix has nothing to do with the driver in question.
Moreover, newer ACPI specification has a support of _DSD method and
special device IDs to allow drivers be enumerated via compatible string.
The slight change to support this kind of enumeration will be added in
sequential patch against pca954x.c.
Revert the commit bbf9d262a1 for good.
Cc: Tin Huynh <tnhuynh@apm.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Peter 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: Julia Cartwright <julia@ni.com>
Signed-off-by: Peter Rosin <peda@axentia.se>
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: Phil Reid <preid@electromag.com.au>
Signed-off-by: Peter 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: Phil Reid <preid@electromag.com.au>
Signed-off-by: Peter Rosin <peda@axentia.se>
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: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
smbus functions return -ve on error, 0 on success. However,
__i2c_transfer() have a different return signature - -ve on error, or
number of buffers transferred (which may be zero or greater.)
The upshot of this is that the sense of the test is reversed when using
the mux on a bus supporting the master_xfer method: we cache the value
and never retry if we fail to transfer any buffers, but if we succeed,
we clear the cached value.
Fix this by making pca954x_reg_write() return a negative error code for
all failure cases.
Fixes: 463e8f845c ("i2c: mux: pca954x: retry updating the mux selection on failure")
Acked-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Pull i2c updates from Wolfram Sang:
- the first series of making i2c_device_id optional instead of
mandatory (in favor of alternatives like of_device_id).
This involves adding a new probe callback (probe_new) which removes
some peculiarities I2C had for a long time now. The new probe is
matching the other subsystems now and the old one will be removed
once all users are converted. It is expected to take a while but
there is ongoing interest in that.
- SMBus Host Notify introduced 4.9 got refactored. They are now using
interrupts instead of the alert callback which solves multiple
issues.
- new drivers for iMX LowPower I2C, Mellanox CPLD and its I2C mux
- significant refactoring for bcm2835 driver
- the usual set of driver updates and improvements
* 'i2c/for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (46 commits)
i2c: fsl-lpi2c: read lpi2c fifo size in probe()
i2c: octeon: thunderx: Remove double-check after interrupt
i2c: octeon: thunderx: TWSI software reset in recovery
i2c: cadence: Allow Cadence I2C to be selected for Cadence Xtensa CPUs
i2c: sh_mobile: Add per-Generation fallback bindings
i2c: rcar: Add per-Generation fallback bindings
i2c: imx-lpi2c: add low power i2c bus driver
dt-bindings: i2c: imx-lpi2c: add devicetree bindings
i2c: designware-pcidrv: Add 10bit address feature to medfield/merrifield
i2c: pxa: Add support for the I2C units found in Armada 3700
i2c: pxa: Add definition of fast and high speed modes via the regs layout
dt-bindings: i2c: pxa: Update the documentation for the Armada 3700
i2c: qup: support SMBus block read
i2c: qup: add ACPI support
i2c: designware: Consolidate default functionality bits
i2c: i2c-mux-gpio: update mux with gpiod_set_array_value_cansleep
i2c: mux: pca954x: Add ACPI support for pca954x
i2c: use an IRQ to report Host Notify events, not alert
i2c: i801: remove SMBNTFDDAT reads as they always seem to return 0
i2c: i801: use the BIT() macro for FEATURES_* also
...
This patch enables ACPI support for mux-pca954x driver.
Signed-off-by: Tin Huynh <tnhuynh@apm.com>
Acked-by: Peter Rosin <peda@axentia.se>
[wsa: removed a trailing whitespace]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Deselect functionality can be ignored for device-trees with
"i2c-mux-idle-disconnect" entries if no platform_data is available.
By enabling the deselect functionality outside the platform_data
block the logic works as it did in previous kernels.
Fixes: 7fcac98071 ("i2c: i2c-mux-pca954x: convert to use an explicit i2c mux core")
Cc: <stable@vger.kernel.org> # v4.7+
Signed-off-by: Alex Hemme <ahemme@cisco.com>
Signed-off-by: Ziyang Wu <ziywu@cisco.com>
[touched up a few minor issues /peda]
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Pull i2c updates from Wolfram Sang:
"Here is the 4.9 pull request from I2C including:
- centralized error messages when registering to the core
- improved lockdep annotations to prevent false positives
- DT support for muxes, gates, and arbitrators
- bus speeds can now be obtained from ACPI
- i2c-octeon got refactored and now supports ThunderX SoCs, too
- i2c-tegra and i2c-designware got a bigger bunch of updates
- a couple of standard driver fixes and improvements"
* 'i2c/for-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (71 commits)
i2c: axxia: disable clks in case of failure in probe
i2c: octeon: thunderx: Limit register access retries
i2c: uniphier-f: fix misdetection of incomplete STOP condition
gpio: pca953x: variable 'id' was used twice
i2c: i801: Add support for Kaby Lake PCH-H
gpio: pca953x: fix an incorrect lockdep warning
i2c: add a warning to i2c_adapter_depth()
lockdep: make MAX_LOCKDEP_SUBCLASSES unconditionally visible
i2c: export i2c_adapter_depth()
i2c: rk3x: Fix variable 'min_total_ns' unused warning
i2c: rk3x: Fix sparse warning
i2c / ACPI: Do not touch an I2C device if it belongs to another adapter
i2c: octeon: Fix high-level controller status check
i2c: octeon: Avoid sending STOP during recovery
i2c: octeon: Fix set SCL recovery function
i2c: rcar: add support for r8a7796 (R-Car M3-W)
i2c: imx: make bus recovery through pinctrl optional
i2c: meson: add gxbb compatible string
i2c: uniphier-f: set the adapter to master mode when probing
i2c: uniphier-f: avoid WARN_ON() of clk_disable() in failure path
...
The cached value of the last selected channel prevents retries on the
next call, even on failure to update the selected channel. Fix that.
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
No longer rely on the implicit matching with the i2c device name, use
an explicit compatible string instead.
Keep a direct pointer to the chip description instead of an index into
the chip description array.
Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Peter Rosin <peda@axentia.se>
Allocate an explicit i2c mux core to handle parent and child adapters
etc. Update the select/deselect ops to be in terms of the i2c mux core
instead of the child adapter.
Add a mask to handle the case where not all child adapters should
cause a mux deselect to happen, now that there is a common deselect op
for all child adapters.
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
i2c_driver does not need to set an owner because i2c_register_driver()
will set it.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
pca9541 and pca954x are calling master_xfer() of the parent adapter directly
thus bypassing the quirks checks of the adapter. Use __i2c_transfer() instead.
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Tested-by: Łukasz Gemborowski <lukasz.gemborowski@nokia.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Jisheng Zhang <jszhang@marvell.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
Fixes: b7f6258402 ("i2c: add quirk checks to core")
Since 39b2bbe3d7 (gpio: add flags argument to gpiod_get*() functions)
which appeared in v3.17-rc1, the gpiod_get* functions take an additional
parameter that allows to specify direction and initial value for
outputs.
Also there is an *_optional variant that serves well here. The sematics
is slightly changed here by using it. Now if a reset gpio is specified
and getting hold on it fails, pca954x_probe fails, too.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Add i2c-mux-idle-disconnect device tree property to PCA954x mux driver. The new
property forces the multiplexer to disconnect child buses in idle state. This is
used, for example, when there are several multiplexers on the same bus and the
devices on the underlying buses might have same I2C addresses.
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nsn.com>
[wsa: added a newline]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
pca954x may be power lost during suspend, so after resume we also suffer
the issue fixed by commit cd823db8b1,
"pca954x power-on default is channel 0 connected. If multiple pca954x
muxes are connected to the same physical I2C bus, the parent bus will
see channel 0 devices behind both muxes by default."
What's more, when resume bootloader may also operate the mux, so the
the channel connected after that may not be the one driver thought.
We fix this problem by putting the mux to disconnected state and
clearing last_chan in the resume hook.
Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The pca954x driver recently switched to the GPIO descriptor API without
including the correct <linux/gpio/consumer.h> header. This breaks
compilation without CONFIG_GPIOLIB.
drivers/i2c/muxes/i2c-mux-pca954x.c: In function ‘pca954x_probe’:
drivers/i2c/muxes/i2c-mux-pca954x.c:204:2: error: implicit declaration
of function ‘devm_gpiod_get’ [-Werror=implicit-function-declaration]
gpio = devm_gpiod_get(&client->dev, "reset");
^
drivers/i2c/muxes/i2c-mux-pca954x.c:204:7: warning: assignment makes
pointer from integer without a cast [enabled by default]
gpio = devm_gpiod_get(&client->dev, "reset");
^
drivers/i2c/muxes/i2c-mux-pca954x.c:206:3: error: implicit declaration
of function ‘gpiod_direction_output’
[-Werror=implicit-function-declaration]
gpiod_direction_output(gpio, 0);
^
cc1: some warnings being treated as errors
make[3]: *** [drivers/i2c/muxes/i2c-mux-pca954x.o] Error 1
Fix it by including the right header.
Reported-by: Jim Davis <jim.epost@gmail.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The ID-based GPIO API pushes handling of GPIO polarity to drivers.
Simplify the driver by switching to the descriptor-based GPIO API.
This also fixes a mismatch between the pca954x DT bindings that document
a "reset-gpios" property and the driver that requests a "reset-gpio"
property.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Pull more i2c updates from Wolfram Sang:
"Mostly bugfixes, small but wanted cleanups, and Paul's init.h removal
applied"
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: rcar: fix NACK error code
i2c: update i2c_algorithm documentation
i2c: rcar: use devm_clk_get to ensure clock is properly ref-counted
i2c: rcar: do not print error if device nacks transfer
i2c: rely on driver core when sanitizing devices
i2c: delete non-required instances of include <linux/init.h>
i2c: acorn: is tristate and should use module.h
i2c: piix4: Standardize log messages
i2c: piix4: Use different message for AMD Auxiliary SMBus Controller
i2c: piix4: Add support for AMD ML and CZ SMBus changes
Pull hwmon updates from Jean Delvare:
"This include it87 driver improvements, and a tree-wide change of my
e-mail address"
* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
Update Jean Delvare's e-mail address
hwmon: (it87) Print proper names for the IT8771E and IT8772E
hwmon: (it87) Add support for the ITE IT8603E
None of these files are actually using any __init type directives
and hence don't need to include <linux/init.h>. Most are just a
left over from __devinit and __cpuinit removal, or simply due to
code getting copied from one driver to the next.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
If a reset GPIO support is specified, request the GPIO and get the chip
out of reset at probe time.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This simplifies error and removal paths.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
i2c_del_mux_adapter() always returns 0. So all checks testing whether it will be
non zero will always evaluate to false and the conditional code is dead code.
This patch updates all callers of i2c_del_mux_adapter() to ignore its return
value and assume that it will always succeed (which it will). A subsequent
patch will make the return type of i2c_del_mux_adapter() void.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Let I2C bus segments behind multiplexers have a class. This allows for
device auto-detection on these segments. As long as parent segments
don't share the same class, it should be fine.
I implemented support in drivers i2c-mux-gpio and i2c-mux-pca954x. I
left i2c-mux-pca9541 and i2c-mux-pinctrl alone for the moment as I
don't know if this feature makes sense for the use cases of these
drivers.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Peter Korsgaard <peter.korsgaard@barco.com>
Cc: David Daney <david.daney@cavium.com>
Cc: Michael Lawnick <ml.lawnick@gmx.de>
Cc: Rodolfo Giometti <giometti@linux.it>
Apply a naming pattern like in the rest of the subsystem to a first set
of mux drivers. Those drivers are the low-hanging fruit; we want to pick
them to motivate upcoming drivers to follow the new pattern. The missing
GPIO driver will be converted in a later patch.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Guenter Roeck <guenter.roeck@ericsson.com> (pca9541)
Acked-by: Jean Delvare <khali@linux-fr.org>
