Commit Graph

267 Commits

Author SHA1 Message Date
Pu Wen 24beb83ad2 i2c-piix4: Add Hygon Dhyana SMBus support
The Hygon Dhyana CPU has the SMBus device with PCI device ID 0x790b,
which is the same as AMD CZ SMBus device. So add Hygon Dhyana support
to the i2c-piix4 driver by using the code path of AMD.

Signed-off-by: Pu Wen <puwen@hygon.cn>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-05-03 16:47:54 +02:00
Wolfram Sang d00afd5ede Merge branch 'i2c-mux/for-next' of https://github.com/peda-r/i2c-mux into i2c/for-5.2
Mainly some pca954x work, i.e. removal of unused platform data support
and added support for sysfs interface for manipulating/examining the
idle state. And then a mechanical cocci-style patch.
2019-05-03 15:20:58 +02:00
Elie Morisse 529766e0a0 i2c: Add drivers for the AMD PCIe MP2 I2C controller
MP2 controllers have two separate busses, so may accommodate up to two I2C
adapters. Those adapters are listed in the ACPI namespace with the
"AMDI0011" HID, and probed by a platform driver.

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

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

Most of the event handling of v3 was rewritten to make it work with more
than one bus (e.g on Ryzen-based Lenovo Yoga 530), and this version
contains many other improvements.

Signed-off-by: Elie Morisse <syniurge@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-03-25 15:21:17 +01:00
Jarkko Nikula 5cd1c56c42 i2c: i801: Add support for Intel Comet Lake
Add PCI ID for Intel Comet Lake PCH.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-03-20 17:42:23 +01:00
Wolfram Sang bb6bdd51c8 i2c: gpio: fault-injector: add 'inject_panic' injector
Add a fault injector simulating a Kernel panic happening after starting
a transfer. Read the docs for its usage.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-23 10:34:08 +01:00
Wolfram Sang 63e57b6f19 i2c: gpio: fault-injector: add 'lose_arbitration' injector
Add a fault injector simulating 'arbitration lost' from multi-master
setups. Read the docs for its usage.

A helper function for future fault injectors using SCL interrupts is
created to achieve this.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-23 10:33:51 +01:00
Wolfram Sang 05bd07280d i2c: gpio: fault-injector: better SPHINX style in docs
We don't use SPHINX currently in I2C documentation; but preparing the
I2C fault injector docs already is a good idea since it makes it easier
to read. Especially as new stuff is going to be added soon.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-05 14:19:55 +01:00
Wolfram Sang 9ac6cb5fbb i2c: add suspended flag and accessors for i2c adapters
A few drivers open code the handling of suspended adapters. It could be
handled by the core, though, to ensure generic handling. This patch adds
the flag and accessor functions. The usage of these helpers is optional,
though. See the kerneldoc in this patch. Using the new flag, we now
reject further transfers if the adapter is already marked suspended.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-01-08 21:01:07 +01:00
Ajay Gupta c71bcdcb42 i2c: add i2c bus driver for NVIDIA GPU
Latest NVIDIA GPU card has USB Type-C interface. There is a
Type-C controller which can be accessed over I2C.

This driver adds I2C bus driver to communicate with Type-C controller.
I2C client driver will be part of USB Type-C UCSI driver.

Signed-off-by: Ajay Gupta <ajayg@nvidia.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
[wsa: kept Makefile sorting]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-11-09 17:46:43 +01:00
Wolfram Sang 82fe39a6bc i2c: refactor function to release a DMA safe buffer
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>
2018-08-30 23:13:15 +02:00
Peter Korsgaard 5d3a01a228 i2c: ocores: update my email address
The old @sunsite.dk address is no longer active, so update the references.

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-24 14:46:43 +02:00
Mika Westerberg 0bff2a8610 i2c: i801: Add support for Intel Ice Lake
Intel Ice Lake has the same SMBus host controller than Intel Cannon
Lake. Add the PCI ID to the drivers list of supported devices.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
[jarkko.nikula@linux.intel.com: Add entries to Documentation and Kconfig]
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-03 23:26:44 +02:00
Jarkko Nikula 80d943ab19 i2c: i801: Consolidate chipset names in documentation and Kconfig
Make list of supported chipsets a little bit shorter by consolidating
names that belong to the same family.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-03 23:19:36 +02:00
Wolfram Sang bbe899700a i2c: gpio: fault-injector: add incomplete_write_byte
Add another injector for an incomplete transfer. As mentioned in the
docs, this one is important to check bus recovery algorithms with it.
Otherwise random data may be sent to devices!

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-03 23:09:36 +02:00
Wolfram Sang 16d55daa56 i2c: gpio: fault-injector: refactor incomplete transfer
Make the incomplete_transfer routine reusable, so we can add other test
cases with different patterns later. Prepare the docs for that, too.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-03 23:09:01 +02:00
Linus Torvalds 9bca19a01d Merge branch 'i2c/for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:

 - mainly feature additions to drivers (stm32f7, qup, xlp9xx, mlxcpld, ...)

 - conversion to use the i2c_8bit_addr_from_msg macro consistently

 - move includes to platform_data

 - core updates to allow the (still in review) I3C subsystem to connect

 - and the regular share of smaller driver updates

* 'i2c/for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (68 commits)
  i2c: qup: fix building without CONFIG_ACPI
  i2c: tegra: Remove suspend-resume
  i2c: imx-lpi2c: Switch to SPDX identifier
  i2c: mxs: Switch to SPDX identifier
  i2c: busses: make use of i2c_8bit_addr_from_msg
  i2c: algos: make use of i2c_8bit_addr_from_msg
  i2c: rcar: document R8A77980 bindings
  i2c: qup: Add command-line parameter to override SCL frequency
  i2c: qup: Correct duty cycle for FM and FM+
  i2c: qup: Add support for Fast Mode Plus
  i2c: qup: add probe path for Centriq ACPI devices
  i2c: robotfuzz-osif: drop pointless test
  i2c: robotfuzz-osif: remove pointless local variable
  i2c: rk3x: Don't print visible virtual mapping MMIO address
  i2c: opal: don't check number of messages in the driver
  i2c: ibm_iic: don't check number of messages in the driver
  i2c: imx: Switch to SPDX identifier
  i2c: mux: pca954x: merge calls to of_match_device and of_device_get_match_data
  i2c: mux: demux-pinctrl: use proper parent device for demux adapter
  i2c: mux: improve error message for failed symlink
  ...
2018-06-14 16:21:46 +09:00
Federico Vaga a0ccb6b54b i2c: ocores: update HDL sources URL
The URL is broken. This patch fixes it.

Signed-off-by: Federico Vaga <federico.vaga@vaga.pv.it>
[wsa: shortened the URL a bit]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-05-29 20:14:32 +02:00
Wolfram Sang 3d8b7a4ea3 Merge branch 'i2c/platform_data-immutable' into i2c/for-4.18 2018-05-17 16:29:19 +02:00
Wolfram Sang 985ecf0037 i2c: ocores: move header to platform_data
This header only contains platform_data. Move it to the proper directory.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Lee Jones <lee.jones@linaro.org>
2018-05-17 16:27:57 +02:00
Wolfram Sang 62ea22c495 i2c: mux: gpio: move header to platform_data
This header only contains platform_data. Move it to the proper directory.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Peter Korsgaard <peter.korsgaard@barco.com>
2018-05-17 16:27:52 +02:00
Michael Shych 27aaa8ad5a i2c: mlxcpld: Add capability register description to documentation
It adds capability register description to documentation.

Signed-off-by: Michael Shych <michaelsh@mellanox.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-30 10:39:29 +02:00
Sam Hansen 40d802cb66 Documentation/i2c: adopt kernel commenting style in examples
The example I2C code is rewritten to adopt the preferred kernel block
commenting style.

Signed-off-by: Sam Hansen <hansens@google.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-18 10:09:44 +02:00
Sam Hansen b50cb3eaf7 Documentation/i2c: sync docs with current state of i2c-tools
Currently, Documentation/i2c/dev-interface describes the use of
i2c_smbus_* helper routines as static inlined functions provided by
linux/i2c-dev.h.  Work has been done to refactor the linux/i2c-dev.h file
in the i2c-tools project out into its own library.  As a result, these
docs have become stale.

This patch corrects the discrepancy and directs the reader to the
i2c-tools project for more information.

Signed-off-by: Sam Hansen <hansens@google.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-18 10:09:15 +02:00
Sam Hansen 675edea10b Documentation/i2c: whitespace cleanup
This strips trailing whitespace in Documentation/i2c/dev-interface.

Signed-off-by: Sam Hansen <hansens@google.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-18 10:07:59 +02:00
Jarkko Nikula 1540779883 i2c: i801: Add missing documentation entries for Braswell and Kaby Lake
Commits adding PCI IDs for Intel Braswell and Kaby Lake PCH-H lacked the
respective Kconfig and Documentation/i2c/busses/i2c-i801 change. Add
them now.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-02-21 09:17:20 +01:00
Linus Torvalds 4141cf676b Merge branch 'i2c/for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
 "I2C has the following changes for you:

   - new flag to mark DMA safe buffers in i2c_msg. Also, some
     infrastructure around it. And docs.

   - huge refactoring of the at24 driver led by the new maintainer
     Bartosz

   - update I2C bus recovery to send STOP after recovery

   - conversion from gpio to gpiod for I2C bus recovery

   - adding a fault-injector to the i2c-gpio driver

   - lots of small driver improvements, and bigger ones to
     i2c-sh_mobile"

* 'i2c/for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (99 commits)
  i2c: mv64xxx: Add myself as maintainer for this driver
  i2c: mv64xxx: Fix clock resource by adding an optional bus clock
  i2c: mv64xxx: Remove useless test before clk_disable_unprepare
  i2c: mxs: use true and false for boolean values
  i2c: meson: update doc description to fix build warnings
  i2c: meson: add configurable divider factors
  dt-bindings: i2c: update documentation for the Meson-AXG
  i2c: imx-lpi2c: add runtime pm support
  i2c: rcar: fix some trivial typos in comments
  i2c: davinci: fix the cpufreq transition
  i2c: rk3x: add proper kerneldoc header
  i2c: rk3x: account for const type of of_device_id.data
  i2c: acorn: remove outdated path from file header
  i2c: acorn: add MODULE_LICENSE tag
  i2c: rcar: implement bus recovery
  i2c: send STOP after successful bus recovery
  i2c: ensure SDA is released in recovery if SDA is controllable
  i2c: add 'set_sda' to bus_recovery_info
  i2c: add identifier in declarations for i2c_bus_recovery
  i2c: make kerneldoc about bus recovery more precise
  ...
2018-02-04 10:57:43 -08:00
Cengiz C 91b28aeb17 i2c: update i2c-dev.h warning in documentation
`Documentation/i2c/dev-interface` gives examples for accessing i2c from
userspace.

There's a note that warns developers about the two `i2c-dev.h` header
files which were shipped with the kernel and i2c-tools separately.

However, following i2c-tools commits suggest that the header files are now
identical (in functionality) and `i2c_*` helper functions are now defined
in a separate header called `i2c/smbus.h`, which is distributed with
i2c-tools:

commit 652619121974 ("Minimize differences with kernel flavor")
commit 93caf007f4cb ("Move SMBus helper functions to include/i2c/smbus.h")

Thus, I've converted the warning paragraph into a historical note and
updated the suggested header files.

Signed-off-by: Cengiz Can <cengizc@gmail.com>
Cc: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2017-12-21 13:39:30 -07:00
Wolfram Sang d4e01186ae i2c: add docs to clarify DMA handling
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-12-03 21:24:59 +01:00
Wolfram Sang 14911c6f48 i2c: gpio: add fault injector
Add fault injection capabilities to the i2c-gpio driver. When connected
to another I2C bus, it can create unusual states which the other I2C bus
master driver needs to handle. Only for debugging!

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2017-12-03 20:33:29 +01:00
Jarkko Nikula cb09d943c7 i2c: i801: Add support for Intel Cedar Fork
Add PCI ID for Intel Cedar Fork PCH.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-10-05 14:44:56 +02:00
Peter Rosin 234fa0ad4e i2c: Documentation: i2c-topology: mention recent driver additions
Specifically mention what drivers are mux-locked and parent-locked.

Signed-off-by: Peter Rosin <peda@axentia.se>
2017-08-22 08:36:57 +02:00
Srinivas Pandruvada 09a1de04d5 i2c: i801: Add support for Intel Cannon Lake
Added SMBUS PCI Ids for SMBUS for Cannon Lake PCH.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
[jarkko.nikula@linux.intel.com: Add entries to Documentation and Kconfig.
Cover Cannon Lake-H too]
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-06-19 16:17:41 +02:00
Wolfram Sang 984b292333 docs: i2c: dev-interface: adapt to new filenames of the i2c core
The I2C core files were renamed, adapt the textfile to it.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-05-31 21:01:05 +02:00
Mika Westerberg 9827f9eb79 i2c: i801: Add support for Intel Gemini Lake
Intel Gemini Lake has the same SMBus host controller than Intel Broxton.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-02-09 17:39:16 +01:00
Peter Rosin 6b66a6f27e i2c: i2c-mux-gpio: rename i2c-gpio-mux to i2c-mux-gpio
The rename did the wrong thing for this documentation file all those
years ago. Fix that as well as the neglected rename of the platform
data structure.

Fixes: e7065e20d9 ("i2c: Rename last mux driver to standard pattern")
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-02-09 17:01:47 +01:00
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
Vadim Pasternak 6bec23bff9 i2c: mlxcpld: add master driver for mellanox systems
Device driver for Mellanox I2C controller logic, implemented in Lattice
CPLD device.
Device supports:
 - Master mode
 - One physical bus
 - Polling mode

The Kconfig currently controlling compilation of this code is:
drivers/i2c/busses/Kconfig:config I2C_MLXCPLD

Signed-off-by: Michael Shych <michaelsh@mellanox.com>
Signed-off-by: Vadim Pasternak <vadimp@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-24 16:21:42 +01:00
Peter Rosin f10a59eb8c i2c: Documentation: i2c-topology: fix minor whitespace nit
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-10 21:18:56 +01:00
Wolfram Sang 30851a7c21 Documentation: i2c: slave-interface: add note for driver development
Make it clear that adding slave support shall not disable master
functionality. We can have both, so we should.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-08 16:57:14 +02:00
Wolfram Sang b4cdaf32ce Documentation: i2c: slave: give proper example for pm usage
pm_runtime_forbid was the wrong knob, this is the better one.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-07-23 22:04:20 +02:00
Wolfram Sang 38fa8afff0 Documentation: i2c: slave: describe buffer problems a bit better
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-07-23 22:00:58 +02:00
Benjamin Tissoires e456cd37bc i2c: smbus: add SMBus Host Notify support
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>
2016-06-17 13:24:05 +02:00
Peter Rosin 1cf79db28e [media] rtl2832: change the i2c gate to be mux-locked
The root i2c adapter lock is then no longer held by the i2c mux during
accesses behind the i2c gate, and such accesses need to take that lock
just like any other ordinary i2c accesses do.

So, declare the i2c gate mux-locked, and zap the regmap overrides
that makes the i2c accesses unlocked and use plain old regmap
accesses. This also removes the need for the regmap wrappers used by
rtl2832_sdr, so deconvolute the code further and provide the regmap
handle directly instead of the wrapper functions.

Tested-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-05-04 22:40:02 +02:00
Antti Palosaari e6d7ffcdf1 [media] si2168: change the i2c gate to be mux-locked
The root i2c adapter lock is then no longer held by the i2c mux during
accesses behind the i2c gate, and such accesses need to take that lock
just like any other ordinary i2c accesses do.

So, declare the i2c gate mux-locked, and zap the code that makes the
i2c accesses unlocked. But add a mutex so that firmware commands are
still serialized.

Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-05-04 22:39:31 +02:00
Peter Rosin 1ffcfaf195 iio: imu: inv_mpu6050: change the i2c gate to be mux-locked
The root i2c adapter lock is then no longer held by the i2c mux during
accesses behind the i2c gate, and such accesses need to take that lock
just like any other ordinary i2c accesses do.

So, declare the i2c gate mux-locked, and zap the code that makes the
unlocked i2c accesses and just use ordinary regmap_write accesses.

This also happens to fix the deadlock described in
http://patchwork.ozlabs.org/patch/584776/ authored by
Adriana Reus <adriana.reus@intel.com> and submitted by
Daniel Baluta <daniel.baluta@intel.com>

----------8<----------
iio: imu: inv_mpu6050: Fix deadlock between i2c adapter lock and mpu lock

This deadlock occurs if the accel/gyro and the sensor on the auxiliary
I2C (in my setup it's an ak8975) are working at the same time.

Scenario:

      T1					T2
     ====				       ====
inv_mpu6050_read_fifo                  aux sensor op (eg. ak8975_read_raw)
        |                                     |
mutex_lock(&indio_dev->mlock)           i2c_transfer
        |                                     |
i2c transaction                         i2c adapter lock
        |                                     |
i2c adapter lock                        i2c_mux_master_xfer
                                              |
                                        inv_mpu6050_select_bypass
                                              |
                                        mutex_lock(&indio_dev->mlock)

When we operate on an mpu sensor the order of locking is mpu lock
followed by the i2c adapter lock. However, when we operate the auxiliary
sensor the order of locking is the other way around.

...
----------8<----------

The reason this patch fixes the deadlock is that T2 does not grab the
i2c adapter lock until the very end (and grabs the newfangled i2c mux
lock where it previously grabbed the i2c adapter lock).

Acked-by: Jonathan Cameron <jic23@kernel.org>
Acked-by: Daniel Baluta <daniel.baluta@intel.com>
Tested-by: Crestez Dan Leonard <leonard.crestez@intel.com>
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-05-04 22:39:30 +02:00
Peter Rosin 2254d24aff i2c: mux: document i2c muxes and elaborate on parent-/mux-locked muxes
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-05-04 22:39:25 +02:00
Masanari Iida 2e049d6132 Doc: i2c: Fix typo in Documentation/i2c
This path fix spelling typos found in Documentation/i2c.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2016-02-10 13:12:14 -07:00
Alexandra Yates cdc5a3110e i2c: i801: add Intel Lewisburg device IDs
Adding Intel codename Lewisburg platform device IDs for SMBus.

Signed-off-by: Alexandra Yates <alexandra.yates@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-11-20 16:22:21 +01:00
Jarkko Nikula 2b630df721 i2c: i801: Document Intel DNV and Broxton
Add missing entries into i2c-i801 documentation and Kconfig about recently
added Intel DNV and Broxton.

Reported-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-26 15:52:59 +01:00