Commit Graph

37 Commits

Author SHA1 Message Date
Wolfram Sang
a8335c64c5 i2c: add slave testunit driver
Here is an I2C slave backend driver which allows to test some uncommon
functionalities of the I2C and SMBus world. Usually, you need specific
devices to test e.g. SMBus Host Notify and such. With this driver you
just need the slave interface of another I2C controller.

This initial version has testcases for multi-master and SMBus Host
Notify. Already planned but not yet implemented are SMBus Alert and
messages with I2C_M_RECV_LEN.

Please read the documentation for further details.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-09-21 11:02:17 +02:00
Jarkko Nikula
ab70935d37 i2c: Remove 'default n' from busses/Kconfig
The default value for a config option defaults to 'n' so it doesn't need
to be set here.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
[jdelvare: found another one]
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-08-25 09:50:04 +02:00
Wolfram Sang
58e64b050d i2c: add Kconfig help text for slave mode
I can't recall why there was none, but we surely want to have it.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-07-04 08:17:53 +02:00
Wolfram Sang
59d3d6042d i2c: slave-eeprom: update documentation
Add more details which have either been missing ever since or describe
recent additions.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Luca Ceresoli <luca@lucaceresoli.net>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-07-04 08:17:53 +02:00
Masahiro Yamada
a7f7f6248d treewide: replace '---help---' in Kconfig files with 'help'
Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.

This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.

There are a variety of indentation styles found.

  a) 4 spaces + '---help---'
  b) 7 spaces + '---help---'
  c) 8 spaces + '---help---'
  d) 1 space + 1 tab + '---help---'
  e) 1 tab + '---help---'    (correct indentation)
  f) 1 tab + 1 space + '---help---'
  g) 1 tab + 2 spaces + '---help---'

In order to convert all of them to 1 tab + 'help', I ran the
following commend:

  $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-14 01:57:21 +09:00
Mauro Carvalho Chehab
ccf988b66d docs: i2c: convert to ReST and add to driver-api bookset
Convert each file at I2C subsystem, renaming them to .rst and
adding to the driver-api book.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-07-31 13:25:27 -06:00
Thomas Gleixner
ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Masahiro Yamada
8636a1f967 treewide: surround Kconfig file paths with double quotes
The Kconfig lexer supports special characters such as '.' and '/' in
the parameter context. In my understanding, the reason is just to
support bare file paths in the source statement.

I do not see a good reason to complicate Kconfig for the room of
ambiguity.

The majority of code already surrounds file paths with double quotes,
and it makes sense since file paths are constant string literals.

Make it treewide consistent now.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
2018-12-22 00:25:54 +09:00
Linus Torvalds
8600b697cd Merge branch 'i2c/for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
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
  ...
2016-12-15 12:56:35 -08:00
Benjamin Tissoires
4d5538f588 i2c: use an IRQ to report Host Notify events, not alert
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>
2016-11-24 16:22:06 +01:00
Linus Walleij
93d710a65e i2c: mux: fix up dependencies
We get the following build error from UM Linux after adding
an entry to drivers/iio/gyro/Kconfig that issues "select I2C_MUX":

ERROR: "devm_ioremap_resource"
   [drivers/i2c/muxes/i2c-mux-reg.ko] undefined!
ERROR: "of_address_to_resource"
   [drivers/i2c/muxes/i2c-mux-reg.ko] undefined!

It appears that the I2C mux core code depends on HAS_IOMEM
for historical reasons, while CONFIG_I2C_MUX_REG does *not*
have a direct dependency on HAS_IOMEM.

This creates a situation where a allyesconfig or allmodconfig
for UM Linux will select I2C_MUX, and will implicitly enable
I2C_MUX_REG as well, and the compilation will fail for the
register driver.

Fix this up by making I2C_MUX_REG depend on HAS_IOMEM and
removing the dependency from I2C_MUX.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Reported-by: Jonathan Cameron <jic23@jic23.retrosnub.co.uk>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Acked-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2016-11-14 18:23:30 +01:00
Jean Delvare
d380a20486 i2c: Update the description of I2C_SMBUS
We support the SMBus Host Notify protocol now.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-07-18 20:11:08 +02:00
Christoph Jaeger
6341e62b21 kconfig: use bool instead of boolean for type definition attributes
Support for keyword 'boolean' will be dropped later on.

No functional change.

Reference: http://lkml.kernel.org/r/cover.1418003065.git.cj@linux.com
Signed-off-by: Christoph Jaeger <cj@linux.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2015-01-07 13:08:04 +01:00
Wolfram Sang
389be323cf i2c: slave-eeprom: add eeprom simulator driver
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>
2014-12-11 22:25:54 +01:00
Lan Tianyu
366047515c i2c: rework kernel config I2C_ACPI
Commit da3c6647(I2C/ACPI: Clean up I2C ACPI code and Add CONFIG_I2C_ACPI
config) adds a new kernel config I2C_ACPI and make I2C core built in
when the config is selected. This is wrong because distributions
etc generally compile I2C as a module and the commit broken that.
This patch is to rename I2C_ACPI to ACPI_I2C_OPREGION. New config
only controls ACPI I2C operation region code and depends on I2C=y.

Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
[wsa: removed unrelated change for Kconfig]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-08-19 10:19:39 -05:00
Lan Tianyu
da3c6647ee I2C/ACPI: Clean up I2C ACPI code and Add CONFIG_I2C_ACPI config
Clean up ACPI related code in the i2c core and add CONFIG_I2C_ACPI
to enable I2C ACPI code.

Current there is a race between removing I2C ACPI operation region
and ACPI AML code accessing. So make i2c core built-in if CONFIG_I2C_ACPI
is set.

Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-06-27 14:50:41 +02:00
Martin Schwidefsky
0244ad004a Remove GENERIC_HARDIRQ config option
After the last architecture switched to generic hard irqs the config
options HAVE_GENERIC_HARDIRQS & GENERIC_HARDIRQS and the related code
for !CONFIG_GENERIC_HARDIRQS can be removed.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-09-13 15:09:52 +02:00
Heiko Carstens
aaaf9cf71c drivers/i2c: remove !S390 dependency, add missing GENERIC_HARDIRQS dependencies
Remove !S390 dependency from i2c Kconfig, since s390 now supports PCI, HAS_IOMEM
and HAS_DMA, however we need to add a couple of GENERIC_HARDIRQS dependecies to
fix compile and link errors like these:

ERROR: "devm_request_threaded_irq" [drivers/i2c/i2c-smbus.ko] undefined!
ERROR: "devm_request_threaded_irq" [drivers/i2c/busses/i2c-ocores.ko] undefined!

Cc: Wolfram Sang <w.sang@pengutronix.de>
Cc: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-03-11 09:59:02 +01:00
Kees Cook
417e86ce5e drivers/i2c: remove depends on CONFIG_EXPERIMENTAL
The CONFIG_EXPERIMENTAL config item has not carried much meaning for a
while now and is almost always enabled by default. As agreed during the
Linux kernel summit, remove it from any "depends on" lines in Kconfigs.

CC: Ralf Baechle <ralf@linux-mips.org>
CC: Manuel Lauss <manuel.lauss@googlemail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-21 14:52:43 -08:00
Peter Huewe
3ddb59d4bc i2c: Make I2C available on UML
Remove the global dependency of the I2C subsystem on HAS_IOMEM and
move the dependency to the i2c/busses submenu, with an exception for
i2c-stub.

The generic I2C part does not need to have HAS_IOMEM set and thus now
becomes available in UML, so the I2C subsystem can now be used, e.g.
by the i2c-stub driver, for development of I2C device drivers.

[JD: Some adjustments.]

[Heiko Carstens: Keep I2C disabled on S390.]

Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-10-05 22:23:52 +02:00
Wolfram Sang
951eef3955 i2c: muxes are not EXPERIMENTAL anymore
We got multiple patches to add mux support to device tree, so people are
using it happily already and build up on it. I also used it in a project
without encountering problems. 20 months of EXPERIMENTAL should do for
this.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Peter Korsgaard <jacmet@sunsite.dk>
Acked-by: Guenter Roeck <guenter.roeck@ericsson.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: Michael Lawnick <ml.lawnick@gmx.de>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: David Daney <ddaney.cavm@gmail.com>
2012-05-12 14:28:16 +02:00
Michael Witten
622e040d57 doc: Kconfig: Typo: square -> squared
Signed-off-by: Michael Witten <mfwitten@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-07-11 14:22:32 +02:00
Arnaud Lacombe
dfc518dd6b Revert "i2c: Fix Kconfig dependencies"
This reverts commit 0a57274ea0.

Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-11-22 11:27:33 -02:00
Jean Delvare
0a57274ea0 i2c: Fix Kconfig dependencies
drivers/i2c/algos/Kconfig makes all the algorithms dependent on
!I2C_HELPER_AUTO, which triggers a Kconfig warning about broken
dependencies when some driver selects one of the algorithms. Ideally
we would make only the prompts dependent on !I2C_HELPER_AUTO, however
Kconfig doesn't currently support that. So we have to redefine the
symbols separately for the I2C_HELPER_AUTO=y case.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Michal Marek <mmarek@suse.cz>
2010-10-24 18:16:57 +02:00
Michael Lawnick
7f528135da i2c: I2C bus multiplexer driver pca954x
I2C driver for PCA954x I2C multiplexer series.

Signed-off-by: Michael Lawnick <ml.lawnick@gmx.de>
Acked-by: Rodolfo Giometti <giometti@linux.it>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-08-11 18:21:03 +02:00
Michael Lawnick
0826374bff i2c: Multiplexed I2C bus core support
Add multiplexed bus core support. I2C multiplexer and switches
like pca954x get instantiated as new adapters per port.

Signed-off-by: Michael Lawnick <ml.lawnick@gmx.de>
Acked-by: Rodolfo Giometti <giometti@linux.it>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-08-11 18:21:02 +02:00
Jean Delvare
e77482d735 i2c: Drop configure option I2C_DEBUG_CHIP
Now that directory drivers/i2c/chips is gone, configuration option
I2C_DEBUG_CHIP no longer has any effect, so we can drop it.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
2010-03-13 20:56:55 +01:00
Jean Delvare
6a9bcced51 tsl2550: Move from i2c/chips to misc
Move the last remaining driver from i2c/chips to misc. Good ridance!

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
2010-03-13 20:56:54 +01:00
Jean Delvare
e2ca307439 i2c: Separate Kconfig option for i2c-smbus
Having a separate Kconfig option for i2c-smbus makes it possible to
build that support as a module even when i2c-core itself is built-in.
Bus drivers which implement SMBus alert should select this option, so
in most cases this option is hidden and the user doesn't have to care
about it.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Trent Piepho <tpiepho@freescale.com>
2010-03-02 12:23:43 +01:00
Mika Kuoppala
194684e596 i2c: Prevent priority inversion on top of bus lock
Low priority thread holding the i2c bus mutex could block higher
priority threads to access the bus resulting in unacceptable
latencies. Change the mutex type to rt_mutex preventing priority
inversion.

Tested-by: Peter Ujfalusi <peter.ujfalusi@nokia.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@nokia.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2009-12-06 17:06:22 +01:00
Jean Delvare
2bb5095aff i2c: Provide compatibility links for i2c adapters
Some user-space applications may be relying on i2c adapters showing up
as class devices in sysfs. Provide compatibility links for them for
the time being. We will remove them after a long transition period.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Kay Sievers <kay.sievers@vrfy.org>
2009-09-18 22:45:46 +02:00
Jean Delvare
8d24f8dcb7 i2c: Let users select algorithm drivers manually again
In kernel 2.6.26, the ability to select I2C algorithm drivers manually
was removed, as all in-kernel drivers do that automatically. However
there were some complaints that it was a problem for out-of-tree I2C
bus drivers. In order to address these complaints, let's allow manual
selection of these drivers again, but still hide them by default for
better general user experience.

This closes bug #11140:
http://bugzilla.kernel.org/show_bug.cgi?id=11140

Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-08-10 22:56:15 +02:00
Martin Schwidefsky
e25df1205f [S390] Kconfig: menus with depends on HAS_IOMEM.
Add "depends on HAS_IOMEM" to a number of menus to make them
disappear for s390 which does not have I/O memory.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-05-10 15:46:07 +02:00
Jan Engelhardt
16538e6b32 Use menuconfig objects - I2C
Allow the whole I2C menu to be disabled at once without diving into
the submenus for deselecting all options (should the user desire so).

Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2007-05-01 23:26:34 +02:00
David Brownell
9c1600eda4 i2c: Add i2c_board_info and i2c_new_device()
This provides partial support for new-style I2C driver binding.  It builds
on "struct i2c_board_info" declarations that identify I2C devices on a given
board.  This is needed on systems with I2C devices that can't be fully probed
and/or autoconfigured, such as many embedded Linux configurations where the
way a given I2C device is wired may affect how it must be used.

There are two models for declaring such devices:

 * LATE -- using a public function i2c_new_device().  This lets modules
   declare I2C devices found *AFTER* a given I2C adapter becomes available.
   
   For example, a PCI card could create adapters giving access to utility
   chips on that card, and this would be used to associate those chips with
   those adapters.

 * EARLY -- from arch_initcall() level code, using a non-exported function
   i2c_register_board_info().  This copies the declarations *BEFORE* such
   an i2c_adapter becomes available, arranging that i2c_new_device() will
   be called later when i2c-core registers the relevant i2c_adapter.

   For example, arch/.../.../board-*.c files would declare the I2C devices
   along with their platform data, and I2C devices would behave much like
   PNPACPI devices.  (That is, both enumerate from board-specific tables.)

To match the exported i2c_new_device(), the previously-private function
i2c_unregister_device() is now exported.

Pending later patches using these new APIs, this is effectively a NOP.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2007-05-01 23:26:31 +02:00
Arthur Othieno
be53f9b2a0 i2c: Fix copy-n-paste in subsystem Kconfig
i2c: Fix copy-n-paste in subsystem Kconfig

We have:
  drivers/i2c/Kconfig:2:# Character device configuration
Which is obviously not true..

Signed-off-by: Arthur Othieno <apgo@patchbomb.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-09-26 15:38:51 -07:00
Linus Torvalds
1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00