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2019-06-08docs: fix broken documentation linksMauro Carvalho Chehab
Mostly due to x86 and acpi conversion, several documentation links are still pointing to the old file. Fix them. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Reviewed-by: Wolfram Sang <wsa@the-dreams.de> Reviewed-by: Sven Van Asbroeck <TheSven73@gmail.com> Reviewed-by: Bhupesh Sharma <bhsharma@redhat.com> Acked-by: Mark Brown <broonie@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-05-03i2c-piix4: Add Hygon Dhyana SMBus supportPu Wen
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>
2019-05-03Merge branch 'i2c-mux/for-next' of https://github.com/peda-r/i2c-mux into ↵Wolfram Sang
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.
2019-03-25i2c: Add drivers for the AMD PCIe MP2 I2C controllerElie Morisse
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>
2019-03-20i2c: i801: Add support for Intel Comet LakeJarkko Nikula
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>
2019-02-23i2c: gpio: fault-injector: add 'inject_panic' injectorWolfram Sang
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>
2019-02-23i2c: gpio: fault-injector: add 'lose_arbitration' injectorWolfram Sang
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>
2019-02-05i2c: gpio: fault-injector: better SPHINX style in docsWolfram Sang
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>
2019-01-08i2c: add suspended flag and accessors for i2c adaptersWolfram Sang
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>
2018-11-09i2c: add i2c bus driver for NVIDIA GPUAjay Gupta
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>
2018-08-30i2c: refactor function to release a DMA safe bufferWolfram Sang
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>
2018-08-24i2c: ocores: update my email addressPeter Korsgaard
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>
2018-07-03i2c: i801: Add support for Intel Ice LakeMika Westerberg
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>
2018-07-03i2c: i801: Consolidate chipset names in documentation and KconfigJarkko Nikula
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>
2018-07-03i2c: gpio: fault-injector: add incomplete_write_byteWolfram Sang
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>
2018-07-03i2c: gpio: fault-injector: refactor incomplete transferWolfram Sang
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>
2018-06-14Merge branch 'i2c/for-4.18' of ↵Linus Torvalds
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 ...
2018-05-29i2c: ocores: update HDL sources URLFederico Vaga
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>
2018-05-17Merge branch 'i2c/platform_data-immutable' into i2c/for-4.18Wolfram Sang
2018-05-17i2c: ocores: move header to platform_dataWolfram Sang
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>
2018-05-17i2c: mux: gpio: move header to platform_dataWolfram Sang
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>
2018-04-30i2c: mlxcpld: Add capability register description to documentationMichael Shych
It adds capability register description to documentation. Signed-off-by: Michael Shych <michaelsh@mellanox.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-18Documentation/i2c: adopt kernel commenting style in examplesSam Hansen
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>
2018-04-18Documentation/i2c: sync docs with current state of i2c-toolsSam Hansen
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>
2018-04-18Documentation/i2c: whitespace cleanupSam Hansen
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>
2018-02-21i2c: i801: Add missing documentation entries for Braswell and Kaby LakeJarkko Nikula
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>
2018-02-04Merge branch 'i2c/for-4.16' of ↵Linus Torvalds
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 ...
2017-12-21i2c: update i2c-dev.h warning in documentationCengiz C
`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>
2017-12-03i2c: add docs to clarify DMA handlingWolfram Sang
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>
2017-12-03i2c: gpio: add fault injectorWolfram Sang
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>
2017-10-05i2c: i801: Add support for Intel Cedar ForkJarkko Nikula
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>
2017-08-22i2c: Documentation: i2c-topology: mention recent driver additionsPeter Rosin
Specifically mention what drivers are mux-locked and parent-locked. Signed-off-by: Peter Rosin <peda@axentia.se>
2017-06-19i2c: i801: Add support for Intel Cannon LakeSrinivas Pandruvada
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>
2017-05-31docs: i2c: dev-interface: adapt to new filenames of the i2c coreWolfram Sang
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>
2017-02-09i2c: i801: Add support for Intel Gemini LakeMika Westerberg
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>
2017-02-09i2c: i2c-mux-gpio: rename i2c-gpio-mux to i2c-mux-gpioPeter Rosin
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: e7065e20d9a6 ("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>
2016-12-15Merge branch 'i2c/for-4.10' of ↵Linus Torvalds
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 ...
2016-11-24i2c: use an IRQ to report Host Notify events, not alertBenjamin Tissoires
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>
2016-11-24i2c: mlxcpld: add master driver for mellanox systemsVadim Pasternak
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>
2016-11-10i2c: Documentation: i2c-topology: fix minor whitespace nitPeter Rosin
Signed-off-by: Peter Rosin <peda@axentia.se> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-08Documentation: i2c: slave-interface: add note for driver developmentWolfram Sang
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>
2016-07-23Documentation: i2c: slave: give proper example for pm usageWolfram Sang
pm_runtime_forbid was the wrong knob, this is the better one. Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-07-23Documentation: i2c: slave: describe buffer problems a bit betterWolfram Sang
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-06-17i2c: smbus: add SMBus Host Notify supportBenjamin Tissoires
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>
2016-05-04[media] rtl2832: change the i2c gate to be mux-lockedPeter Rosin
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[media] si2168: change the i2c gate to be mux-lockedAntti Palosaari
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>
2016-05-04iio: imu: inv_mpu6050: change the i2c gate to be mux-lockedPeter Rosin
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>
2016-05-04i2c: mux: document i2c muxes and elaborate on parent-/mux-locked muxesPeter Rosin
Signed-off-by: Peter Rosin <peda@axentia.se> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-02-10Doc: i2c: Fix typo in Documentation/i2cMasanari Iida
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>
2015-11-20i2c: i801: add Intel Lewisburg device IDsAlexandra Yates
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>