a) rename to 'put' instead of 'release' to match 'get' when obtaining
the buffer
b) change the argument order to have the buffer as first argument
c) add a new argument telling the function if the message was
transferred. This allows the function to be used also in cases
where setting up DMA failed, so the buffer needs to be freed without
syncing to the message buffer.
Also convert the only user.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
There aren't any users left. Remove this callback from the 2.4 times.
Phew, finally, that took years to reach...
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
There are two drivers already using the SDA hold time setting.
It might be more in the future, thus, make I2C core to parse the setting
for us if provided by firmware.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Some adapters do not support a message length of 0. Add this as a quirk
so drivers don't have to open code it.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Some IP cores have an internal 'bus free' logic which may be more
advanced than just checking if SDA is high. Add a separate callback to
get this status. Filling it is optional.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
For bus recovery, we either need to bail out early if we can read SDA or
we need to send STOP after every pulse. Otherwise recovery might be
misinterpreted as an unwanted write. So, require one of those SDA
handling functions to avoid this problem.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The i2c_lock_adapter name is ambiguous since it is unclear if it
refers to the root adapter or the adapter you name in the argument.
The natural interpretation is the adapter you name in the argument,
but there are historical reasons for that not being the case; it
in fact locks the root adapter. Just remove the function and force
users to spell out the I2C_LOCK_ROOT_ADAPTER name to indicate what
is really going on. Also remove i2c_unlock_adapter, of course.
This patch was generated with
git grep -l 'i2c_\(un\)\?lock_adapter' \
| xargs sed -i 's/i2c_\(un\)\?lock_adapter(\([^)]*\))/'\
'i2c_\1lock_bus(\2, I2C_LOCK_ROOT_ADAPTER)/g'
followed by white-space touch-up.
Signed-off-by: Peter Rosin <peda@axentia.se>
Acked-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Tested-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Removes all locking from i2c_smbus_xfer and renames it to __i2c_smbus_xfer,
then adds a new i2c_smbus_xfer function that simply grabs the lock while
calling the unlocked variant.
This is not perfectly equivalent, since i2c_smbus_xfer was callable from
atomic/irq context if you happened to end up emulating SMBus with an I2C
transfer, and that is no longer the case with this patch. It is unknown
(to me) if anything depends on that quirk, but it seems fragile enough to
simply break those cases and require them to call i2c_transfer directly
instead.
While at it, for consistency rename the 2nd to last argument (size) of
the i2c_smbus_xfer declaration to protocol and remove the surplus extern
marker.
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
I3C busses have to know about all I2C devices connected on the I3C bus
to properly initialize the I3C master, and I2C frames can't be sent on
the bus until this initialization is done.
We can't let the I2C core parse the DT and instantiate I2C devices as
part of its i2c_add_adapter() procedure because, when done this way,
I2C devices are directly registered to the device-model and might be
attached to drivers which could in turn start sending frames on the bus,
which won't work since, as said above, the bus is not yet initialized.
Export of_i2c_register_device() in order to let the I3C core parse the
I2C device nodes by itself and initialize the bus.
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The only user of i2c_board_info->archdata is the OF parsing code and it
just pass a zero-initialized object which has the same effect as leaving
->archdata to NULL since the client object is allocated with kzalloc().
Get rid of this useless field.
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Can be used during probe to double check that the probed device is
what is expected.
Loosely based on code from Adrian Fiergolski <adrian.fiergolski@cern.ch>.
Tested-by: Adrian Fiergolski <adrian.fiergolski@cern.ch>
Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Peter Rosin <peda@axentia.se>
This will be needed when we want to create STOP conditions, too, later.
Create the needed fields and populate them for the GPIO case if the GPIO
is set to output.
Tested-by: Phil Reid <preid@electromag.com.au>
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>
No reason to have them undefined, so let's add them.
Tested-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
"Used internally" is vague. What it actually means is that those fields
are populated by the core if valid GPIOs are provided. Change the
comments to reflect that.
Tested-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Use the new helper to create variants of i2c_master_{send|recv} which
mark their buffers as DMA safe.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Those two functions are very similar, the only differences are that one
needs the I2C_M_RD flag for its message while the other one needs the
buffer casted to drop the const. Introduce a generic helper which allows
to specify the flags (also needed later for DMA safe variants of these
calls) and let the casting be done in the inlining functions which are
now calling the new helper function.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
One helper checks if DMA is suitable and optionally creates a bounce
buffer, if not. The other function returns the bounce buffer and makes
sure the data is properly copied back to the message.
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Remove all reference to code related to using integer based ids for
scl/sda gpio for bus recovery. All in tree drivers are now using the
gpio descriptors to specific the required gpios.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Phil Reid <preid@electromag.com.au>
Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Currently the i2c gpio recovery code uses gpio integer interface
instead of the gpiod. This change switch the core code to use
the gpiod while still retaining compatibility with the gpio integer
interface. This will allow individual driver to be updated and tested
individual to switch to using the gpiod interface.
Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Using the macro IS_ENABLED to check the option CONFIG_I2C=(y|m) makes
the code nicer. No functional change.
Signed-off-by: Stefan Lengfeld <contact@stefanchrist.eu>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
For devices not instantiated through ACPI the i2c-client's device-name
gets set to <busnr>-<addr> by default, e.g. "0-0022" this means that
the device-name is dependent on the order in which the i2c-busses are
enumerated.
In some cases having a predictable constant device-name is desirable,
for example on non device-tree platforms the link between a regulator
and its consumers is specified by the platform code by setting
regulator_init_data.consumers. This array identifies the regulator's
consumers by dev_name and supply(-name). Which requires a constant
dev_name.
This commit adds a dev_name field to i2c_board_info allowing
platform code to set a contstant dev_name so that the device can
be identified by its dev_name in other platform code.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Mark Brown <broonie@kernel.org> (live at ELCE17)
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> (live at ELCE17)
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Drivers would like to call i2c_detect_slave_mode() even if !I2C_SLAVE.
Give them what they want to,
Otherwise kernel will not compile:
drivers/i2c/busses/i2c-designware-platdrv.c: In function ‘dw_i2c_plat_probe’:
drivers/i2c/busses/i2c-designware-platdrv.c:331:6: error: implicit declaration of function ‘i2c_detect_slave_mode’ [-Werror=implicit-function-declaration]
if (i2c_detect_slave_mode(&pdev->dev))
^~~~~~~~~~~~~~~~~~~~~
cc1: some warnings being treated as errors
Fixes: 6e38cf3b44 ("i2c: designware: Let slave adapter support be optional")
Reported-by: Abdul Haleem <abdhalee@linux.vnet.ibm.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Pull input subsystem updates from Dmitry Torokhov:
- a big update from Mauro converting input documentation to ReST format
- Synaptics PS/2 is now aware of SMBus companion devices, which means
that we can now use native RMI4 protocol to handle touchpads, instead
of relying on legacy PS/2 mode.
- we removed support from BMA180 accelerometer from input devices as it
is now handled properly by IIO
- update to TSC2007 to corretcly report pressure
- other miscellaneous driver fixes.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (152 commits)
Input: ar1021_i2c - use BIT to check for a bit
Input: twl4030-pwrbutton - use input_set_capability() helper
Input: twl4030-pwrbutton - use correct device for irq request
Input: ar1021_i2c - enable touch mode during open
Input: add uinput documentation
dt-bindings: input: add bindings document for ar1021_i2c driver
dt-bindings: input: rotary-encoder: fix typo
Input: xen-kbdfront - add module parameter for setting resolution
ARM: pxa/raumfeld: fix compile error in rotary controller resources
Input: xpad - do not suggest writing to Dominic
Input: xpad - don't use literal blocks inside footnotes
Input: xpad - note that usb/devices is now at /sys/kernel/debug/
Input: docs - freshen up introduction
Input: docs - split input docs into kernel- and user-facing
Input: docs - note that MT-A protocol is obsolete
Input: docs - update joystick documentation a bit
Input: docs - remove disclaimer/GPL notice
Input: fix "Game console" heading level in joystick documentation
Input: rotary-encoder - remove references to platform data from docs
Input: move documentation for Amiga CD32
...
By default the i2c-core will try to get an irq with index 0 on ACPI / of
instantiated devices. This is troublesome on some ACPI systems where the
irq info at index 0 in the CRS table may contain nonsense and/or point
to an irqchip for which there is no Linux driver.
If this happens then before this commit the driver's probe method would
never get called because i2c_device_probe will try to get an irq by
calling acpi_dev_gpio_irq_get which will always return -EPROBE in this
case, as it waits for a matching irqchip driver to load. Thus causing
the driver to not get a chance to bind.
This commit adds a new disable_i2c_core_irq_mapping flag to struct
i2c_driver which a driver can set to tell the core to skip irq mapping.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
By default the i2c subsys creates an i2c-client for the first I2cSerialBus
resource of an acpi_device, but some acpi_devices have multiple
I2cSerialBus resources and we may want to instantiate i2c-clients for
the others.
This commit adds a new i2c_acpi_new_device function which can be used to
create an i2c-client for any I2cSerialBus resource of an acpi_device.
Note that the other resources may even be on a different i2c bus, so just
retrieving the client address is not enough.
Here is an example DSDT excerpt from such a device:
Device (WIDR)
{
Name (_HID, "INT33FE" /* XPOWER Battery Device */)
Name (_CID, "INT33FE" /* XPOWER Battery Device */)
Name (_DDN, "WC PMIC Battery Device")
<snip>
Name (RBUF, ResourceTemplate ()
{
I2cSerialBusV2 (0x005E, ControllerInitiated, 0x000186A0,
AddressingMode7Bit, "\\_SB.PCI0.I2C7",
0x00, ResourceConsumer, , Exclusive,
)
I2cSerialBusV2 (0x0036, ControllerInitiated, 0x000186A0,
AddressingMode7Bit, "\\_SB.PCI0.I2C1",
0x00, ResourceConsumer, , Exclusive,
)
I2cSerialBusV2 (0x0022, ControllerInitiated, 0x00061A80,
AddressingMode7Bit, "\\_SB.PCI0.I2C1",
0x00, ResourceConsumer, , Exclusive,
)
I2cSerialBusV2 (0x0054, ControllerInitiated, 0x00061A80,
AddressingMode7Bit, "\\_SB.PCI0.I2C1",
0x00, ResourceConsumer, , Exclusive,
)
GpioInt (Level, ActiveLow, Exclusive, PullNone, 0x0000,
"\\_SB.PCI0.I2C7.PMI5", 0x00, ResourceConsumer, ,
)
{ // Pin list
0x0012
}
GpioInt (Edge, ActiveLow, ExclusiveAndWake, PullNone, 0x0000,
"\\_SB.GPO1", 0x00, ResourceConsumer, ,
)
{ // Pin list
0x0005
}
GpioInt (Level, ActiveLow, Exclusive, PullNone, 0x0000,
"\\_SB.PCI0.I2C7.PMI5", 0x00, ResourceConsumer, ,
)
{ // Pin list
0x0013
}
})
Method (_CRS, 0, NotSerialized) // _CRS: Current Resource Settings
{
Return (RBUF) /* \_SB_.PCI0.I2C7.WIDR.RBUF */
}
<snip>
}
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Simple integer for interrupt number is not expressive enough, as it does
not convey interrupt trigger type that should be used. Let's allow
attaching array of resources to the board info and have i2c core parse
first IRQ resource and set up interrupt trigger as needed.
Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
i2c bus has 2 different types of device belonging to the same bus and
bus notifiers use device type to distinguish between adapters and clients.
Previously we only had i2c_adapter_type exported, which made code wanting
to work with i2c_client devices test for type not equal to adapter type.
This unfortunately is not safe if we ever add another type to the bus,
so let's export i2c_client_type as well.
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Fix up missing #includes in other places that rely on sched.h doing that for them.
Acked-by: Linus 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: Ingo Molnar <mingo@kernel.org>
Pull i2c updates from Wolfram Sang:
"I2C has for you two new drivers (Tegra BPMP and STM32F4), interrupt
support for pca954x muxes, and a bunch of driver bugfixes and
improvements. Nothing really special this cycle.
A few commits have been added to my tree just recently. Those are the
Tegra BPMP driver and a few straightforward bugfixes or cleanups which
I prefer to have upstream rather soonish. The rest had proper
linux-next exposure"
* 'i2c/for-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (25 commits)
i2c: thunderx: Replace pci_enable_msix()
i2c: exynos5: fix arbitration lost handling
i2c: exynos5: disable fifo-almost-empty irq signal when necessary
i2c: at91: ensure state is restored after suspending
i2c: bcm2835: Avoid possible NULL ptr dereference
i2c: Add Tegra BPMP I2C proxy driver
dt-bindings: Add Tegra186 BPMP I2C binding
misc: eeprom: at24: use device_property_*() functions instead of of_get_property()
i2c: mux: pca954x: Add interrupt controller support
dt: bindings: i2c-mux-pca954x: Add documentation for interrupt controller
i2c: mux: pca954x: Add missing pca9542 definition to chip_desc
i2c: riic: correctly finish transfers
i2c: i801: Add support for Intel Gemini Lake
i2c: mux: pca9541: Export OF device ID table as module aliases
i2c: mux: pca954x: Export OF device ID table as module aliases
i2c: mux: mlxcpld: remove unused including <linux/version.h>
i2c: busses: constify i2c_algorithm structures
i2c: i2c-mux-gpio: rename i2c-gpio-mux to i2c-mux-gpio
i2c: sh_mobile: document support for r8a7796 (R-Car M3-W)
i2c: i2c-cros-ec-tunnel: Reduce logging noise
...
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: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This function has the purpose of mode detection by checking the
device nodes for a reg matching with the I2C_OWN_SLAVE_ADDREESS flag.
Currently only checks using OF functions (ACPI slave not supported yet).
Signed-off-by: Luis Oliveira <lolivei@synopsys.com>
Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Falling back unconditionally to HostNotify as primary client's interrupt
breaks some drivers which alter their functionality depending on whether
interrupt is present or not, so let's introduce a board flag telling I2C
core explicitly if we want wired interrupt or HostNotify-based one:
I2C_CLIENT_HOST_NOTIFY.
For DT-based systems we introduce "host-notify" property that we convert
to I2C_CLIENT_HOST_NOTIFY board flag.
Tested-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Pali Rohár <pali.rohar@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The current SMBus Host Notify implementation relies on .alert() to
relay its notifications. However, the use cases where SMBus Host
Notify is needed currently is to signal data ready on touchpads.
This is closer to an IRQ than a custom API through .alert().
Given that the 2 touchpad manufacturers (Synaptics and Elan) that
use SMBus Host Notify don't put any data in the SMBus payload, the
concept actually matches one to one.
Benefits are multiple:
- simpler code and API: the client will just have an IRQ, and
nothing needs to be added in the adapter beside internally
enabling it.
- no more specific workqueue, the threading is handled by IRQ core
directly (when required)
- no more races when removing the device (the drivers are already
required to disable irq on remove)
- simpler handling for drivers: use plain regular IRQs
- no more dependency on i2c-smbus for i2c-i801 (and any other adapter)
- the IRQ domain is created automatically when the adapter exports
the Host Notify capability
- the IRQ are assign only if ACPI, OF and the caller did not assign
one already
- the domain is automatically destroyed on remove
- fewer lines of code (minus 20, yeah!)
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This will aid the seamless removal of the current probe()'s, more
commonly unused than used second parameter. Most I2C drivers can
simply switch over to the new interface, others which have DT
support can use its own matching instead and others can call
i2c_match_id() themselves. This brings I2C's device probe method
into line with other similar interfaces in the kernel and prevents
the requirement to pass an i2c_device_id table.
Suggested-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
[Kieran: fix rebase conflicts and adapt for dev_pm_domain_{attach,detach}]
Tested-by: Kieran Bingham <kieran@bingham.xyz>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
When there was no other way to match a I2C device to driver i2c_match_id()
was exclusively used. However, now there are other types of tables which
are commonly supplied, matching on an i2c_device_id table is used less
frequently. Instead of _always_ calling i2c_match_id() from within the
framework, we only need to do so from drivers which have no other way of
matching. This patch makes i2c_match_id() available to the aforementioned
device drivers.
Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Tested-by: Kieran Bingham <kieran@bingham.xyz>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This function provides a single call for all I2C devices which need to
match firstly using traditional OF means i.e by of_node, then if that
fails we attempt to match using the supplied I2C client name with a
list of supplied compatible strings with the '<vendor>,' string
removed. The latter is required due to the unruly naming conventions
used currently by I2C devices.
Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
[Kieran: Fix static inline usage on !CONFIG_OF]
Tested-by: Kieran Bingham <kieran@bingham.xyz>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Kieran Bingham <kieran@bingham.xyz>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
For crazy setups in which an i2c gpio expander is behind an i2c gpio
multiplexer controlled by a gpio provided a second expander using the
same device driver we need to explicitly tell lockdep how to handle
nested locking.
Export i2c_adapter_depth() as public API to be reused outside of i2c
core code.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: Peter Rosin <peda@axentia.se>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This makes it trivial to constify them, so do that.
Signed-off-by: Peter Rosin <peda@axentia.se>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
ACPI 5 specification doesn't have property for the I2C bus speed but
I2cSerialBus resource descriptor which define each controller-slave
connection define the maximum speed supported by that connection.
Thus finding the maximum safe speed for the bus is to walk through all
I2cSerialBus resources that are associated to I2C controller and use the
speed of slowest connection.
Add function i2c_acpi_find_bus_speed() to the i2c-core that adapter
drivers can call prior registering itself to core.
This implies two-step walk through the I2cSerialBus resources: call to
i2c_acpi_find_bus_speed() does the first scan and finds the safe bus
speed that adapter drivers can set up. Adapter driver registration does
the second scan when i2c-core creates the I2C slaves by calling the
i2c_acpi_register_devices(). In that way the bus speed is set in case
slave device probe gets called during registration and does communication.
Previous version commit 55d38d060e ("i2c: core: Add function for finding
the bus speed from ACPI") got reverted due merge conflicts from
commit 525e6fabea ("i2c / ACPI: add support for ACPI reconfigure
notifications").
This version is a bit bigger than previous version but is still sharing
the lowest and complicated part of I2cSerialBus lookup routines with the
existing code.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This unifies usage with i2c_lock_bus and i2c_unlock_bus, and paves the
way for the next patch which looks a bit saner with this preparatory
work taken care of beforehand.
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This reverts commit 55d38d060e. There were
too heavy merge conflicts and the driver code making use of this was not
ready yet anyhow. So, we wait one cycle.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
ACPI 5 specification doesn't have property for the I2C bus speed but
I2cSerialBus resource descriptors which define each controller-slave
connection define the maximum speed supported by that connection.
Thus finding the maximum safe speed for the bus is to walk all
I2cSerialBus resources that are associated to I2C controller and use
the speed of slowest connection.
Add function i2c_acpi_find_bus_speed() to the i2c-core that adapter
drivers can call prior registering itself to core.
This implies two-step walk through the I2cSerialBus resources: call to
i2c_acpi_find_bus_speed() does the first scan and finds the safe bus
speed that adapter drivers can set up. Adapter driver registration does
the second scan when i2c-core creates the I2C slaves by calling the
i2c_acpi_register_devices(). In that way the bus speed is set in case
slave device probe gets called during registration and does
communication.
Implement this by reusing the existing ACPI I2C walk routines in the
i2c-core. Extend them so that slowest connection speed is saved during
the walk and I2C slaves are registered only when calling through the
i2c_acpi_register_devices() with the i2c_adapter pointer.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
SMBus Host Notify allows a slave device to act as a master on a bus to
notify the host of an interrupt. On Intel chipsets, the functionality
is directly implemented in the firmware. We just need to export a
function to call .alert() on the proper device driver.
i2c_handle_smbus_host_notify() behaves like i2c_handle_smbus_alert().
When called, it schedules a task that will be able to sleep to go through
the list of devices attached to the adapter.
The current implementation allows one Host Notification to be scheduled
while an other is running.
Tested-by: Andrew Duggan <aduggan@synaptics.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
.alert() is meant to be generic, but there is currently no way
for the device driver to know which protocol generated the alert.
Add a parameter in .alert() to help the device driver to understand
what is given in data.
This patch is required to have the support of SMBus Host Notify protocol
through .alert().
Tested-by: Andrew Duggan <aduggan@synaptics.com>
For hwmon:
Acked-by: Guenter Roeck <linux@roeck-us.net>
For IPMI:
Acked-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Some I2C devices have multiple addresses assigned, for example each address
corresponding to a different internal register map page of the device.
So far drivers which need support for this have handled this with a driver
specific and non-generic implementation, e.g. passing the additional address
via platform data.
This patch provides a new helper function called i2c_new_secondary_device()
which is intended to provide a generic way to get the secondary address
as well as instantiate a struct i2c_client for the secondary address.
The function expects a pointer to the primary i2c_client, a name
for the secondary address and an optional default address. The name is used
as a handle to specify which secondary address to get.
The default address is used as a fallback in case no secondary address
was explicitly specified. In case no secondary address and no default
address were specified the function returns NULL.
For now the function only supports look-up of the secondary address
from devicetree, but it can be extended in the future
to for example support board files and/or ACPI.
Signed-off-by: Jean-Michel Hautbois <jean-michel.hautbois@veo-labs.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
With a i2c topology like the following
GPIO ---| ------ BAT1
| v /
I2C -----+----------+---- MUX
| \
EEPROM ------ BAT2
there is a locking problem with the GPIO controller since it is a client
on the same i2c bus that it muxes. Transfers to the mux clients (e.g. BAT1)
will lock the whole i2c bus prior to attempting to switch the mux to the
correct i2c segment. In the above case, the GPIO device is an I/O expander
with an i2c interface, and since the GPIO subsystem knows nothing (and
rightfully so) about the lockless needs of the i2c mux code, this results
in a deadlock when the GPIO driver issues i2c transfers to modify the
mux.
So, observing that while it is needed to have the i2c bus locked during the
actual MUX update in order to avoid random garbage on the slave side, it
is not strictly a must to have it locked over the whole sequence of a full
select-transfer-deselect mux client operation. The mux itself needs to be
locked, so transfers to clients behind the mux are serialized, and the mux
needs to be stable during all i2c traffic (otherwise individual mux slave
segments might see garbage, or worse).
Introduce this new locking concept as "mux-locked" muxes, and call the
pre-existing mux locking scheme "parent-locked".
Modify the i2c mux locking so that muxes that are "mux-locked" locks only
the muxes on the parent adapter instead of the whole i2c bus when there is
a transfer to the slave side of the mux. This lock serializes transfers to
the slave side of the muxes on the parent adapter.
Add code to i2c-mux-gpio and i2c-mux-pinctrl that checks if all involved
gpio/pinctrl devices have a parent that is an i2c adapter in the same
adapter tree that is muxed, and request a "mux-locked mux" if that is the
case.
Modify the select-transfer-deselect code for "mux-locked" muxes so
that each of the select-transfer-deselect ops locks the mux parent
adapter individually.
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Add i2c_lock_bus() and i2c_unlock_bus(), which call the new lock_bus and
unlock_bus ops in the adapter. These funcs/ops take an additional flags
argument that indicates for what purpose the adapter is locked.
There are two flags, I2C_LOCK_ROOT_ADAPTER and I2C_LOCK_SEGMENT, but they
are both implemented the same. For now. Locking the root adapter means
that the whole bus is locked, locking the segment means that only the
current bus segment is locked (i.e. i2c traffic on the parent side of
a mux is still allowed even if the child side of the mux is locked).
Also support a trylock_bus op (but no function to call it, as it is not
expected to be needed outside of the i2c core).
Implement i2c_lock_adapter/i2c_unlock_adapter in terms of the new locking
scheme (i.e. lock with the I2C_LOCK_ROOT_ADAPTER flag).
Locking the root adapter and locking the segment is the same thing for
all root adapters (e.g. in the normal case of a simple topology with no
i2c muxes). The two locking variants are also the same for traditional
muxes (aka parent-locked muxes). These muxes traverse the tree, locking
each level as they go until they reach the root. This patch is preparatory
for a later patch in the series introducing mux-locked muxes, which behave
differently depending on the requested locking. Since all current users
are using i2c_lock_adapter, which is a wrapper for I2C_LOCK_ROOT_ADAPTER,
we only need to annotate the calls that will not need to lock the root
adapter for mux-locked muxes. I.e. the instances that needs to use
I2C_LOCK_SEGMENT instead of i2c_lock_adapter/I2C_LOCK_ROOT_ADAPTER. Those
instances are in the i2c_transfer and i2c_smbus_xfer functions, so that
mux-locked muxes can single out normal i2c accesses to its slave side
and adjust the locking for those accesses.
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Drivers do this in various ways, let's use one standard way of doing it.
Note: I2C_M_RD is bit 0, so the code could be simplified. To be extremly
robust and to advertise good coding practices, I still use the ternary
operator and let the compilers do the optimizing job.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
