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2018-08-30i2c: refactor function to release a DMA safe bufferWolfram Sang1-5/+6
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: remove deprecated attach_adapter callbackWolfram Sang1-10/+1
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>
2018-08-21Merge branch 'i2c/for-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linuxLinus Torvalds1-32/+53
Pull i2c updates from Wolfram Sang: - the core has now a lockless variant of i2c_smbus_xfer. Some open coded versions of this got removed in drivers. This also enables proper SCCB support in regmap. - locking got a more precise naming. i2c_{un}lock_adapter() had to go, and we know use i2c_lock_bus() consistently with flags like I2C_LOCK_ROOT_ADAPTER and I2C_LOCK_SEGMENT to avoid ambiguity. - the gpio fault injector got a new delicate testcase - the bus recovery procedure got fixed to handle the new testcase correctly - a new quirk flag for controllers not able to handle zero length messages together with driver updates to use it - new drivers: FSI bus attached I2C masters, GENI I2C controller, Owl family S900 - and a good set of driver improvements and bugfixes * 'i2c/for-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (77 commits) i2c: rcar: implement STOP and REP_START according to docs i2c: rcar: refactor private flags i2c: core: ACPI: Make acpi_gsb_i2c_read_bytes() check i2c_transfer return value i2c: core: ACPI: Properly set status byte to 0 for multi-byte writes dt-bindings: i2c: rcar: Add r8a774a1 support dt-bindings: i2c: sh_mobile: Add r8a774a1 support i2c: imx: Simplify stopped state tracking i2c: imx: Fix race condition in dma read i2c: pasemi: remove hardcoded bus numbers on smbus i2c: designware: Add SPDX license tag i2c: designware: Convert to use struct i2c_timings i2c: core: Parse SDA hold time from firmware i2c: designware-pcidrv: Mark expected switch fall-through i2c: amd8111: Mark expected switch fall-through i2c: sh_mobile: use core to detect 'no zero length read' quirk i2c: xlr: use core to detect 'no zero length' quirk i2c: rcar: use core to detect 'no zero length' quirk i2c: stu300: use core to detect 'no zero length' quirk i2c: pmcmsp: use core to detect 'no zero length' quirk i2c: mxs: use core to detect 'no zero length' quirk ...
2018-08-08i2c: core: Parse SDA hold time from firmwareAndy Shevchenko1-0/+2
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>
2018-08-04i2c: quirks: add zero length checksWolfram Sang1-0/+6
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>
2018-07-25i2c/mux, locking/core: Annotate the nested rt_mutex usagePeter Rosin1-1/+1
If an i2c topology has instances of nested muxes, then a lockdep splat is produced when when i2c_parent_lock_bus() is called. Here is an example: ============================================ WARNING: possible recursive locking detected -------------------------------------------- insmod/68159 is trying to acquire lock: (i2c_register_adapter#2){+.+.}, at: i2c_parent_lock_bus+0x32/0x50 [i2c_mux] but task is already holding lock: (i2c_register_adapter#2){+.+.}, at: i2c_parent_lock_bus+0x32/0x50 [i2c_mux] other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(i2c_register_adapter#2); lock(i2c_register_adapter#2); *** DEADLOCK *** May be due to missing lock nesting notation 1 lock held by insmod/68159: #0: (i2c_register_adapter#2){+.+.}, at: i2c_parent_lock_bus+0x32/0x50 [i2c_mux] stack backtrace: CPU: 13 PID: 68159 Comm: insmod Tainted: G O Call Trace: dump_stack+0x67/0x98 __lock_acquire+0x162e/0x1780 lock_acquire+0xba/0x200 rt_mutex_lock+0x44/0x60 i2c_parent_lock_bus+0x32/0x50 [i2c_mux] i2c_parent_lock_bus+0x3e/0x50 [i2c_mux] i2c_smbus_xfer+0xf0/0x700 i2c_smbus_read_byte+0x42/0x70 my2c_init+0xa2/0x1000 [my2c] do_one_initcall+0x51/0x192 do_init_module+0x62/0x216 load_module+0x20f9/0x2b50 SYSC_init_module+0x19a/0x1c0 SyS_init_module+0xe/0x10 do_syscall_64+0x6c/0x1a0 entry_SYSCALL_64_after_hwframe+0x42/0xb7 Reported-by: John Sperbeck <jsperbeck@google.com> Tested-by: John Sperbeck <jsperbeck@google.com> Signed-off-by: Peter Rosin <peda@axentia.se> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Deepa Dinamani <deepadinamani@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Chang <dpf@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: Wolfram Sang <wsa@the-dreams.de> Link: http://lkml.kernel.org/r/20180720083914.1950-3-peda@axentia.se Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-21i2c: recovery: make pin init look like STOPWolfram Sang1-9/+10
When we initialize the pins, make sure it looks like STOP by dividing the delay into halves. It shouldn't matter because SDA is expected to be held low by a device, but for super-safety, let's do it. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com> Reviewed-by: Peter Rosin <peda@axentia.se> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-17i2c: recovery: rename variable for easier understandingWolfram Sang1-7/+7
While refactoring the routine before, it occurred to me that this will make the code much easier to understand. 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>
2018-07-17i2c: recovery: add get_bus_free callbackWolfram Sang1-4/+23
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>
2018-07-17i2c: recovery: refactor recovery functionWolfram Sang1-18/+6
After exiting the while loop, we checked if recovery was successful and sent a STOP to the clients. Meanwhile however, we send a STOP after every pulse, so it is not needed after the loop. If we move the check for a free bus to the end of the while loop, we can shorten and simplify the logic. It is still ensured that at least one STOP will be sent to the wire even if SDA was not stuck low. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Peter Rosin <peda@axentia.se> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-17i2c: recovery: require either get_sda or set_sdaWolfram Sang1-1/+6
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>
2018-07-12i2c: recovery: if possible send STOP with recovery pulsesWolfram Sang1-1/+10
I2C clients may misunderstand recovery pulses if they can't read SDA to bail out early. In the worst case, as a write operation. To avoid that and if we can write SDA, try to send STOP to avoid the misinterpretation. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Peter Rosin <peda@axentia.se> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2018-06-14Merge branch 'i2c/for-4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linuxLinus Torvalds1-6/+4
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 ...
2018-05-22i2c: Retain info->of_node in i2c_new_device()Boris Brezillon1-2/+4
Currently, of_i2c_register_devices() is responsible for retaining info->of_node, but we're about to expose a function to parse I2C board info without registering the I2C device. We could possibly let this function retain ->of_node, but this approach is prone to reference leak since people will have to remember to call of_node_put() if something goes wrong between the OF node parsing and the registration step. Let's just retain the ->of_node in i2c_new_register() instead. Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-05-15i2c: Get rid of i2c_board_info->archdataBoris Brezillon1-4/+0
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>
2018-05-14i2c: Respect all error codes from dev_pm_domain_attach()Ulf Hansson1-1/+1
The limitation of being able to check only for -EPROBE_DEFER from dev_pm_domain_attach() has been removed. Hence let's respect all error codes and bail out accordingly. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-04-11i2c: add param sanity check to i2c_transfer()Ard Biesheuvel1-0/+3
The API docs describe i2c_transfer() as taking a pointer to an array of i2c_msg containing at least 1 entry, but leaves it to the individual drivers to sanity check the msgs and num parameters. Let's do this in core code instead. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> [wsa: changed '<= 0' to '< 1'] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-03i2c: Update i2c_trace_msg static key to modern apiDavidlohr Bueso1-6/+7
No changes in refcount semantics -- key init is false; replace static_key_slow_inc|dec with static_branch_inc|dec static_key_false with static_branch_unlikely Added a '_key' suffix to i2c_trace_msg, for better self documentation. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Reviewed-by: David Howells <dhowells@redhat.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-04-03i2c: fix parameter of trace_i2c_resultAhbong Chang1-1/+1
According to the event i2c_result defined in include/trace/events/i2c.h, the second parameter should be the number of messages instead of the ended loop index. The value of ended loop index is the same as ret. Signed-off-by: Ahbong Chang <cwahbong@google.com> Reviewed-by: Todd Poynor <toddpoynor@google.com> Reviewed-by: David Howells <dhowells@redhat.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-03-24i2c: make i2c_check_addr_validity() staticWolfram Sang1-1/+1
After previous refactoring, there is only one user in the same file left. Make the function static now. [wsa: added 'int' to bare 'unsigned'] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-03-17Merge branch 'i2c-mux/for-next' of https://github.com/peda-r/i2c-mux into i2c/for-4.17Wolfram Sang1-0/+33
"These patches verify the device id of the PCA984x mux chips using standardized (but rarely implemented) i2c device identification."
2018-03-06i2c: add i2c_get_device_id() to get the standard i2c device idPeter Rosin1-0/+33
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>
2018-03-05i2c: core: report OF style module alias for devices registered via OFJavier Martinez Canillas1-0/+8
The buses should honor the firmware interface used to register the device, but the I2C core reports a MODALIAS of the form i2c:<device> even for I2C devices registered via OF. This means that user-space will never get an OF stype uevent MODALIAS even when the drivers modules contain aliases exported from both the I2C and OF device ID tables. For example, an Atmel maXTouch Touchscreen registered by a DT node with compatible "atmel,maxtouch" has the following module alias: $ cat /sys/class/i2c-adapter/i2c-8/8-004b/modalias i2c:maxtouch So udev won't be able to auto-load a module for an OF-only device driver. Many OF-only drivers duplicate the OF device ID table entries in an I2C ID table only has a workaround for how the I2C core reports the module alias. This patch changes the I2C core to report an OF related MODALIAS uevent if the device was registered via OF. So for the previous example, after this patch, the reported MODALIAS for the Atmel maXTouch will be the following: $ cat /sys/class/i2c-adapter/i2c-8/8-004b/modalias of:NtrackpadT<NULL>Catmel,maxtouch NOTE: This patch may break out-of-tree drivers that were relying on this behavior, and only had an I2C device ID table even when the device was registered via OF. There are no remaining drivers in mainline that do this, but out-of-tree drivers have to be fixed and define a proper OF device ID table to have module auto-loading working. Signed-off-by: Javier Martinez Canillas <javierm@redhat.com> Tested-by: Dmitry Mastykin <mastichi@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-02-04Merge branch 'i2c/for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linuxLinus Torvalds1-116/+96
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 ...
2018-01-17i2c: core: decrease reference count of device node in i2c_unregister_deviceLixin Wang1-1/+5
Reference count of device node was increased in of_i2c_register_device, but without decreasing it in i2c_unregister_device. Then the added device node will never be released. Fix this by adding the of_node_put. Signed-off-by: Lixin Wang <alan.1.wang@nokia-sbell.com> Tested-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2018-01-16i2c: send STOP after successful bus recoveryWolfram Sang1-0/+12
If we managed to get a client release SDA again, send a STOP afterwards to make sure we have a consistent state on the bus again. 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>
2018-01-16i2c: ensure SDA is released in recovery if SDA is controllableWolfram Sang1-0/+2
If we have a function to control SDA, we should ensure that SDA is not held down by us. So, release the GPIO in this case. 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>
2018-01-16i2c: add 'set_sda' to bus_recovery_infoWolfram Sang1-1/+10
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>
2017-12-03i2c: refactor i2c_master_{send_recv}Wolfram Sang1-46/+18
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>
2017-12-03i2c: add helpers to ease DMA handlingWolfram Sang1-0/+46
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>
2017-11-28i2c: core: fix compile issue related to incorrect gpio headerPhil Reid1-1/+1
The correct header to include for the gpiod interface is <linux/gpio/consumer.h>. Fixes: 3991c5c80beaf7eb9 ("i2c: Switch to using gpiod interface for gpio bus recovery") 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>
2017-11-27i2c: remove legacy integer scl/sda gpio for recoveryPhil Reid1-76/+2
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>
2017-11-27i2c: Switch to using gpiod interface for gpio bus recoveryPhil Reid1-4/+17
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>
2017-11-02i2c: Make i2c_unregister_device() NULL-awareAndy Shevchenko1-2/+3
It's a common pattern to be NULL-aware when freeing resources. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-11-01Merge branch 'i2c/sbs-manager' into i2c/for-4.15Wolfram Sang1-0/+9
2017-10-28i2c: core: call of_i2c_setup_smbus_alert in i2c_register_adapterPhil Reid1-0/+9
Add a call to of_i2c_setup_smbus_alert when a i2c adapter is registered so the the smbalert driver can be registered. Signed-off-by: Phil Reid <preid@electromag.com.au> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-10-28i2c: generic recovery: check SCL before SDAClaudio Foellmi1-3/+7
Move the check for a stuck SCL before the check for a high SDA. This prevent false positives in the specific case that SDA is fine and SCL is stuck, which previously returned 0. Also check SDA again after the loop, if we can. Together, these changes should lead to a lot more failed recoveries being caught and returning error codes. Signed-off-by: Claudio Foellmi <claudio.foellmi@ergon.ch> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-10-27i2c: Allow overriding dev_name through board_infoHans de Goede1-2/+8
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>
2017-08-14i2c: core: Make comment about I2C table requirement to reflect the codeJavier Martinez Canillas1-2/+2
I2C drivers were required to have an I2C device ID table even if were for devices that would only be registered using a specific firmware interface (e.g: OF or ACPI). But commit da10c06a044b ("i2c: Make I2C ID tables non-mandatory for DT'ed devices") changed the I2C core to relax the requirement and allow drivers to avoid defining this table. Unfortunately it only took into account drivers for OF-only devices and forgot about ACPI-only ones, and this was fixed by commit c64ffff7a9d1 ("i2c: core: Allow empty id_table in ACPI case as well"). But the latter didn't update the original comment, so it doesn't reflect what the code does now. Signed-off-by: Javier Martinez Canillas <javierm@redhat.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-07-31i2c: core: Allow empty id_table in ACPI case as wellAndy Shevchenko1-0/+1
For now empty ID table is not allowed with ACPI and prevents driver to be probed. Add a check to allow empty ID table. This introduces a helper i2c_acpi_match_device(). Note, we rename some static function in i2c-core-acpi.c to distinguish with public API. Fixes: da10c06a044b ("i2c: Make I2C ID tables non-mandatory for DT'ed devices") Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Rajmohan Mani <rajmohan.mani@intel.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> [wsa: needed to get some drivers probed again] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-05-31i2c: reformat core-base file headerWolfram Sang1-21/+22
Finally, apply modern comment rules to the file header. The old style looked very non-Linuxish and challenged my eyes for some time now. I also added my own copyright for the period of me being the maintainer. Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-05-31i2c: remove unneeded includes from coreWolfram Sang1-2/+0
They seem like cruft to me. I couldn't find any evidence that something included from there is actually used. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-05-31i2c: break out ACPI support into separate fileWolfram Sang1-648/+0
Removes some ifdeffery. Also add the new file to the relevant MAINTAINERS section. Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-05-31i2c: break out OF support into separate fileWolfram Sang1-264/+1
Also removes some ifdeffery. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-05-31i2c: break out smbus support into separate fileWolfram Sang1-574/+0
Break out the exported SMBus functions and the emulation layer into a separate file. This also involved splitting up the tracing header into an I2C and an SMBus part. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-05-31i2c: break out slave support into separate fileWolfram Sang1-101/+1
Also removes some ifdeffery. Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-05-31i2c: rename core source file to allow refactorizationWolfram Sang1-0/+3831
The I2C core became quite huge and its monolithic structure makes maintenance hard. So, prepare to break out some functionality into separate files by renaming the source file. Note that we keep the resulting object name constant to avoid regressions. Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
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