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2015-01-30i2c: sh_mobile: terminate DMA reads properlyWolfram Sang1-1/+11
DMA read requests could miss proper termination, so two more bytes would have been read via PIO overwriting the end of the buffer with wrong data. Make DMA stop handling more readable while we are here. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-26i2c: Only include slave support if selectedJean Delvare2-0/+3
Make the slave support depend on CONFIG_I2C_SLAVE. Otherwise it gets included unconditionally, even when it is not needed. I2C bus drivers which implement slave support must select I2C_SLAVE. Signed-off-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-24i2c: s3c2410: fix ABBA deadlock by keeping clock preparedPaul Osmialowski1-6/+17
This patch solves deadlock between clock prepare mutex and regmap mutex reported by Tomasz Figa in [1] by implementing solution from [2]: "always leave the clock of the i2c controller in a prepared state". [1] https://lkml.org/lkml/2014/7/2/171 [2] https://lkml.org/lkml/2014/7/2/207 On each i2c transfer handled by s3c24xx_i2c_xfer(), clk_prepare_enable() was called, which calls clk_prepare() then clk_enable(). clk_prepare() takes prepare_lock mutex before proceeding. Note that i2c transfer functions are invoked from many places in kernel, typically with some other additional lock held. It may happen that function on CPU1 (e.g. regmap_update_bits()) has taken a mutex (i.e. regmap lock mutex) then it attempts i2c communication in order to proceed (so it needs to obtain clock related prepare_lock mutex during transfer preparation stage due to clk_prepare() call). At the same time other task on CPU0 wants to operate on clock (e.g. to (un)prepare clock for some other reason) so it has taken prepare_lock mutex. CPU0: CPU1: clk_disable_unused() regulator_disable() clk_prepare_lock() map->lock(map->lock_arg) regmap_read() s3c24xx_i2c_xfer() map->lock(map->lock_arg) clk_prepare_lock() Implemented solution from [2] leaves i2c clock prepared. Preparation is done in s3c24xx_i2c_probe() function. Without this patch, it is immediately unprepared by clk_disable_unprepare() call. I've replaced this call with clk_disable() and I've added clk_unprepare() call in s3c24xx_i2c_remove(). The s3c24xx_i2c_xfer() function now uses clk_enable() instead of clk_prepare_enable() (and clk_disable() instead of clk_unprepare_disable()). Signed-off-by: Paul Osmialowski <p.osmialowsk@samsung.com> Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2015-01-24i2c: slave-eeprom: fix boundary check when using sysfsWolfram Sang1-2/+2
Due to a copy&paste error, the last byte of the shared memory was not accessible via sysfs. Reported-by: Debora Grosse <debora@mds.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-20Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linuxLinus Torvalds3-189/+252
Pull more i2c updates from Wolfram Sang: "Included are two bugfixes needing some bigger refactoring (sh_mobile: deferred probe with DMA, mv64xxx: fix offload support) and one deprecated driver removal I thought would go in via ppc but I misunderstood. It has a proper ack from BenH" * 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: i2c: sh_mobile: fix uninitialized var when debug is enabled macintosh: therm_pm72: delete deprecated driver i2c: sh_mobile: I2C_SH_MOBILE should depend on HAS_DMA i2c: sh_mobile: rework deferred probing i2c: sh_mobile: refactor DMA setup i2c: mv64xxx: rework offload support to fix several problems i2c: mv64xxx: use BIT() macro for register value definitions
2014-12-20i2c: sh_mobile: fix uninitialized var when debug is enabledWolfram Sang1-0/+1
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-19Merge tag 'powerpc-3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linuxLinus Torvalds3-0/+306
Pull second batch of powerpc updates from Michael Ellerman: "The highlight is the series that reworks the idle management on powernv, which allows us to use deeper idle states on those machines. There's the fix from Anton for the "BUG at kernel/smpboot.c:134!" problem. An i2c driver for powernv. This is acked by Wolfram Sang, and he asked that we take it through the powerpc tree. A fix for audit from rgb at Red Hat, acked by Paul Moore who is one of the audit maintainers. A patch from Ben to export the symbol map of our OPAL firmware as a sysfs file, so that tools can use it. Also some CXL fixes, a couple of powerpc perf fixes, a fix for smt-enabled, and the patch to add __force to get_user() so we can use bitwise types" * tag 'powerpc-3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: powerpc/powernv: Ignore smt-enabled on Power8 and later powerpc/uaccess: Allow get_user() with bitwise types powerpc/powernv: Expose OPAL firmware symbol map powernv/powerpc: Add winkle support for offline cpus powernv/cpuidle: Redesign idle states management powerpc/powernv: Enable Offline CPUs to enter deep idle states powerpc/powernv: Switch off MMU before entering nap/sleep/rvwinkle mode i2c: Driver to expose PowerNV platform i2c busses powerpc: add little endian flag to syscall_get_arch() power/perf/hv-24x7: Use kmem_cache_free() instead of kfree powerpc/perf/hv-24x7: Use per-cpu page buffer cxl: Unmap MMIO regions when detaching a context cxl: Add timeout to process element commands cxl: Change contexts_lock to a mutex to fix sleep while atomic bug powerpc: Secondary CPUs must set cpu_callin_map after setting active and online
2014-12-17i2c: sh_mobile: I2C_SH_MOBILE should depend on HAS_DMAGeert Uytterhoeven1-0/+1
If NO_DMA=y: drivers/built-in.o: In function `sh_mobile_i2c_dma_unmap': i2c-sh_mobile.c:(.text+0x60de42): undefined reference to `dma_unmap_single' drivers/built-in.o: In function `sh_mobile_i2c_xfer_dma': i2c-sh_mobile.c:(.text+0x60df22): undefined reference to `dma_map_single' i2c-sh_mobile.c:(.text+0x60df2e): undefined reference to `dma_mapping_error' Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-17i2c: sh_mobile: rework deferred probingWolfram Sang1-50/+48
DMA is opt-in for this driver. So, we can't use deferred probing for requesting DMA channels in probe, because our driver would get endlessly deferred if DMA support is compiled in AND the DMA driver is missing. Because we can't know when the DMA driver might show up, we always try again when a DMA transfer would be possible. The downside is that there is more overhead for setting up PIO transfers under the above scenario. But well, having DMA enabled and the proper DMA driver missing looks like a broken or test config anyhow. Reported-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-17i2c: sh_mobile: refactor DMA setupWolfram Sang1-19/+16
Refactor DMA setup to keep the errno so we can implement better deferred probe support in the next step. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-17i2c: mv64xxx: rework offload support to fix several problemsThomas Petazzoni1-120/+186
Originally, the I2C controller supported by the i2c-mv64xxx driver requires a lot of software support: an interrupt is generated at each step of an I2C transaction (after the start bit, after sending the address, etc.) and the driver is in charge of re-programming the I2C controller to do the next step of the I2C transaction. This explains the fairly complex state machine that the driver has. On Marvell Armada XP and later processors (Armada 375, 38x, etc.), the I2C controller was extended with a part called the "I2C Bridge", which allows to offload the I2C transaction completely to the hardware. Initial support for this mechanism was added in commit 930ab3d403a ("i2c: mv64xxx: Add I2C Transaction Generator support"). However, the implementation done in this commit has two related issues, which this commit fixes by completely changing how the offload implementation is done: * SMBus read transfers, where there is one write to select the register immediately followed in the same transaction by one read, were making the processor hang. This was easier visible on the Marvell Armada XP WRT1900AC platform using a driver for an I2C LED controller, or on other Armada XP platforms by using a simple 'i2cget' command to read an I2C EEPROM. * The implementation was based on the fact that the offload engine was re-programmed to transfer each message of an I2C xfer: this meant that each message sent with the offload engine was starting with a normal I2C start sequence. However, the I2C subsystem assumes that all messages belonging to the same xfer will use the so-called "repeated start" so that the entire I2C xfer is seen as one transfer by the I2C devices and cannot be interrupt by other I2C masters on the same bus. In fact, the "I2C Bridge" allows to offload three types of xfer: - xfer of one write message - xfer of one read message - xfer of one write message followed by one read message For all other situations, we have to fallback to not using the "I2C Bridge" in order to get proper I2C semantics. Therefore, this commit reworks the offload implementation to put it not at the message level, but at the xfer level: in the mv64xxx_i2c_xfer() function, we decide if the transaction can be offloaded (in which case it is handled by the mv64xxx_i2c_offload_xfer() function), or otherwise it is handled by the slow path (implemented in the existing mv64xxx_i2c_execute_msg()). This allows to simplify the state machine, which no longer needs to have any state related to the offload implementation: the offload implementation is now completely separated from the slow path (with the exception of the interrupt handler, of course). In summary: - mv64xxx_i2c_can_offload() will analyze an I2C xfer and decided of the "I2C Bridge" can be used to offload it or not. - mv64xxx_i2c_offload_xfer() will actually program the "I2C Bridge" to offload one xfer (of either one or two messages), and block using mv64xxx_i2c_wait_for_completion() until the xfer completes. - The interrupt handler mv64xxx_i2c_intr() is modified to push the offload related code to a separate function, mv64xxx_i2c_intr_offload(). It will take care of reading the received data if needed. This commit was tested on: - Armada XP OpenBlocks AX3-4 (EEPROM on I2C and RTC on I2C) - Armada XP WRT1900AC (LED controller on I2C) - Armada XP GP (EEPROM on I2C) Fixes: 930ab3d403ae ("i2c: mv64xxx: Add I2C Transaction Generator support") Cc: <stable@vger.kernel.org> # v3.12+ Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> [wsa: fixed checkpatch warnings] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-17i2c: mv64xxx: use BIT() macro for register value definitionsThomas Petazzoni1-11/+11
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-14Merge tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-coreLinus Torvalds52-52/+0
Pull driver core update from Greg KH: "Here's the set of driver core patches for 3.19-rc1. They are dominated by the removal of the .owner field in platform drivers. They touch a lot of files, but they are "simple" changes, just removing a line in a structure. Other than that, a few minor driver core and debugfs changes. There are some ath9k patches coming in through this tree that have been acked by the wireless maintainers as they relied on the debugfs changes. Everything has been in linux-next for a while" * tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits) Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries" fs: debugfs: add forward declaration for struct device type firmware class: Deletion of an unnecessary check before the function call "vunmap" firmware loader: fix hung task warning dump devcoredump: provide a one-way disable function device: Add dev_<level>_once variants ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries ath: use seq_file api for ath9k debugfs files debugfs: add helper function to create device related seq_file drivers/base: cacheinfo: remove noisy error boot message Revert "core: platform: add warning if driver has no owner" drivers: base: support cpu cache information interface to userspace via sysfs drivers: base: add cpu_device_create to support per-cpu devices topology: replace custom attribute macros with standard DEVICE_ATTR* cpumask: factor out show_cpumap into separate helper function driver core: Fix unbalanced device reference in drivers_probe driver core: fix race with userland in device_add() sysfs/kernfs: make read requests on pre-alloc files use the buffer. sysfs/kernfs: allow attributes to request write buffer be pre-allocated. fs: sysfs: return EGBIG on write if offset is larger than file size ...
2014-12-14Merge branch 'i2c/for-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linuxLinus Torvalds23-171/+3456
Pull i2c updates from Wolfram Sang: "For 3.19, the I2C subsystem has to offer special candy this time. Right in time for Christmas :) - I2C slave framework: finally, a generic mechanism for Linux being an I2C slave (if the bus driver supports that). Docs are still missing but will come later this cycle, the code is good enough to go. - I2C muxes represent their topology in sysfs much more detailed. This will help users to navigate around much easier. - irq population of i2c clients is now done at probe time, not device creation time, to have better support for deferred probing. - new drivers for Imagination SCB, Amlogic Meson - DMA support added for Freescale IMX, Renesas SHMobile - slightly bigger driver updates to OMAP, i801, AT91, and rk3x (mostly quirk handling, timing updates, and using better kernel interfaces) - eeprom driver can now write with byte-access (very slow, but OK to have) - and the bunch of smaller fixes, cleanups, ID updates..." * 'i2c/for-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (56 commits) i2c: sh_mobile: remove unneeded DMA mask i2c: rcar: add slave support i2c: slave-eeprom: add eeprom simulator driver i2c: core changes for slave support MAINTAINERS: add I2C dt bindings also to I2C realm i2c: designware: Fix falling time bindings doc i2c: davinci: switch to use platform_get_irq Documentation: i2c: Use PM ops instead of legacy suspend/resume i2c: sh_mobile: optimize irq entry i2c: pxa: add support for SCCB devices omap: i2c: don't check bus state IP rev3.3 and earlier i2c: s3c2410: Handle i2c sys_cfg register in i2c driver i2c: rk3x: add Kconfig dependency on COMMON_CLK i2c: omap: add notes related to i2c multimaster mode i2c: omap: don't reset controller if Arbitration Lost detected i2c: omap: implement workaround for handling invalid BB-bit values i2c: omap: cleanup register definitions i2c: rk3x: handle dynamic clock rate changes correctly i2c: at91: enable probe deferring on dma channel request i2c: at91: remove legacy DMA support ...
2014-12-14i2c: Driver to expose PowerNV platform i2c bussesNeelesh Gupta3-0/+306
The patch exposes the available i2c busses on the PowerNV platform to the kernel and implements the bus driver to support i2c and smbus commands. The driver uses the platform device infrastructure to probe the busses on the platform and registers them with the i2c driver framework. Signed-off-by: Neelesh Gupta <neelegup@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Wolfram Sang <wsa@the-dreams.de> (I2C part, excluding the bindings) Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-12-11i2c: sh_mobile: remove unneeded DMA maskWolfram Sang1-3/+0
We don't need the mask since we obtain the channels via DT. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-11i2c: rcar: add slave supportWolfram Sang1-9/+115
The first I2C slave provider using the new generic interface. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-11i2c: slave-eeprom: add eeprom simulator driverWolfram Sang3-0/+181
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>
2014-12-11i2c: core changes for slave supportWolfram Sang1-0/+49
Finally(!), make Linux support being an I2C slave. Most of the existing infrastructure is reused. We mainly add i2c_slave_register/unregister() calls which tells i2c bus drivers to activate the slave mode. Then, they also get a callback to report slave events to. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-11Merge tag 'devicetree-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/glikely/linuxLinus Torvalds1-45/+104
Pull devicetree changes from Grant Likely: "Lots of activity in the devicetree code for v3.18. Most of it is related to getting all of the overlay support code in place, but there are other important things in there. Highlights: - OF_RECONFIG notifiers for SPI, I2C and Platform devices. Those subsystems can now respond to live changes to the device tree. - CONFIG_OF_OVERLAY method for applying live changes to the device tree - Removal of the of_allnodes list. This used to be used to iterate over all the nodes in the device tree, but it is unnecessary because the same thing can be done by iterating over the list of child pointers. Getting rid of of_allnodes saves some memory and avoids the possibility of of_allnodes being sorted differently from the child lists. - Support for retrieving original DTB blob via sysfs. Needed by kexec. - More unittests - Documentation and minor bug fixes" * tag 'devicetree-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/glikely/linux: (42 commits) of: Delete unnecessary check before calling "of_node_put()" of: Drop ->next pointer from struct device_node spi: Check for spi_of_notifier when CONFIG_OF_DYNAMIC=y of: support passing console options with stdout-path of: add optional options parameter to of_find_node_by_path() of: Add bindings for chosen node, stdout-path of: Remove unneeded and incorrect MODULE_DEVICE_TABLE ARM: dt: fix up PL011 device tree bindings of: base, fix of_property_read_string_helper kernel-doc of: remove select of non-existant OF_DEVICE config symbol spi/of: Add OF notifier handler spi/of: Create new device registration method and accessors i2c/of: Add OF_RECONFIG notifier handler i2c/of: Factor out Devicetree registration code of/overlay: Add overlay unittests of/overlay: Introduce DT overlay support of/reconfig: Add OF_DYNAMIC notifier for platform_bus_type of/reconfig: Always use the same structure for notifiers of/reconfig: Add debug output for OF_RECONFIG notifiers of/reconfig: Add empty stubs for the of_reconfig methods ...
2014-12-10Merge tag 'pm+acpi-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pmLinus Torvalds4-4/+3
Pull ACPI and power management updates from Rafael Wysocki: "This time we have some more new material than we used to have during the last couple of development cycles. The most important part of it to me is the introduction of a unified interface for accessing device properties provided by platform firmware. It works with Device Trees and ACPI in a uniform way and drivers using it need not worry about where the properties come from as long as the platform firmware (either DT or ACPI) makes them available. It covers both devices and "bare" device node objects without struct device representation as that turns out to be necessary in some cases. This has been in the works for quite a few months (and development cycles) and has been approved by all of the relevant maintainers. On top of that, some drivers are switched over to the new interface (at25, leds-gpio, gpio_keys_polled) and some additional changes are made to the core GPIO subsystem to allow device drivers to manipulate GPIOs in the "canonical" way on platforms that provide GPIO information in their ACPI tables, but don't assign names to GPIO lines (in which case the driver needs to do that on the basis of what it knows about the device in question). That also has been approved by the GPIO core maintainers and the rfkill driver is now going to use it. Second is support for hardware P-states in the intel_pstate driver. It uses CPUID to detect whether or not the feature is supported by the processor in which case it will be enabled by default. However, it can be disabled entirely from the kernel command line if necessary. Next is support for a platform firmware interface based on ACPI operation regions used by the PMIC (Power Management Integrated Circuit) chips on the Intel Baytrail-T and Baytrail-T-CR platforms. That interface is used for manipulating power resources and for thermal management: sensor temperature reporting, trip point setting and so on. Also the ACPI core is now going to support the _DEP configuration information in a limited way. Basically, _DEP it supposed to reflect off-the-hierarchy dependencies between devices which may be very indirect, like when AML for one device accesses locations in an operation region handled by another device's driver (usually, the device depended on this way is a serial bus or GPIO controller). The support added this time is sufficient to make the ACPI battery driver work on Asus T100A, but it is general enough to be able to cover some other use cases in the future. Finally, we have a new cpufreq driver for the Loongson1B processor. In addition to the above, there are fixes and cleanups all over the place as usual and a traditional ACPICA update to a recent upstream release. As far as the fixes go, the ACPI LPSS (Low-power Subsystem) driver for Intel platforms should be able to handle power management of the DMA engine correctly, the cpufreq-dt driver should interact with the thermal subsystem in a better way and the ACPI backlight driver should handle some more corner cases, among other things. On top of the ACPICA update there are fixes for race conditions in the ACPICA's interrupt handling code which might lead to some random and strange looking failures on some systems. In the cleanups department the most visible part is the series of commits targeted at getting rid of the CONFIG_PM_RUNTIME configuration option. That was triggered by a discussion regarding the generic power domains code during which we realized that trying to support certain combinations of PM config options was painful and not really worth it, because nobody would use them in production anyway. For this reason, we decided to make CONFIG_PM_SLEEP select CONFIG_PM_RUNTIME and that lead to the conclusion that the latter became redundant and CONFIG_PM could be used instead of it. The material here makes that replacement in a major part of the tree, but there will be at least one more batch of that in the second part of the merge window. Specifics: - Support for retrieving device properties information from ACPI _DSD device configuration objects and a unified device properties interface for device drivers (and subsystems) on top of that. As stated above, this works with Device Trees and ACPI and allows device drivers to be written in a platform firmware (DT or ACPI) agnostic way. The at25, leds-gpio and gpio_keys_polled drivers are now going to use this new interface and the GPIO subsystem is additionally modified to allow device drivers to assign names to GPIO resources returned by ACPI _CRS objects (in case _DSD is not present or does not provide the expected data). The changes in this set are mostly from Mika Westerberg, Rafael J Wysocki, Aaron Lu, and Darren Hart with some fixes from others (Fabio Estevam, Geert Uytterhoeven). - Support for Hardware Managed Performance States (HWP) as described in Volume 3, section 14.4, of the Intel SDM in the intel_pstate driver. CPUID is used to detect whether or not the feature is supported by the processor. If supported, it will be enabled automatically unless the intel_pstate=no_hwp switch is present in the kernel command line. From Dirk Brandewie. - New Intel Broadwell-H ID for intel_pstate (Dirk Brandewie). - Support for firmware interface based on ACPI operation regions used by the PMIC chips on the Intel Baytrail-T and Baytrail-T-CR platforms for power resource control and thermal management (Aaron Lu). - Limited support for retrieving off-the-hierarchy dependencies between devices from ACPI _DEP device configuration objects and deferred probing support for the ACPI battery driver based on the _DEP information to make that driver work on Asus T100A (Lan Tianyu). - New cpufreq driver for the Loongson1B processor (Kelvin Cheung). - ACPICA update to upstream revision 20141107 which only affects tools (Bob Moore). - Fixes for race conditions in the ACPICA's interrupt handling code and in the ACPI code related to system suspend and resume (Lv Zheng and Rafael J Wysocki). - ACPI core fix for an RCU-related issue in the ioremap() regions management code that slowed down significantly after CPUs had been allowed to enter idle states even if they'd had RCU callbakcs queued and triggered some problems in certain proprietary graphics driver (and elsewhere). The fix replaces synchronize_rcu() in that code with synchronize_rcu_expedited() which makes the issue go away. From Konstantin Khlebnikov. - ACPI LPSS (Low-Power Subsystem) driver fix to handle power management of the DMA engine included into the LPSS correctly. The problem is that the DMA engine doesn't have ACPI PM support of its own and it simply is turned off when the last LPSS device having ACPI PM support goes into D3cold. To work around that, the PM domain used by the ACPI LPSS driver is redesigned so at least one device with ACPI PM support will be on as long as the DMA engine is in use. From Andy Shevchenko. - ACPI backlight driver fix to avoid using it on "Win8-compatible" systems where it doesn't work and where it was used by default by mistake (Aaron Lu). - Assorted minor ACPI core fixes and cleanups from Tomasz Nowicki, Sudeep Holla, Huang Rui, Hanjun Guo, Fabian Frederick, and Ashwin Chaugule (mostly related to the upcoming ARM64 support). - Intel RAPL (Running Average Power Limit) power capping driver fixes and improvements including new processor IDs (Jacob Pan). - Generic power domains modification to power up domains after attaching devices to them to meet the expectations of device drivers and bus types assuming devices to be accessible at probe time (Ulf Hansson). - Preliminary support for controlling device clocks from the generic power domains core code and modifications of the ARM/shmobile platform to use that feature (Ulf Hansson). - Assorted minor fixes and cleanups of the generic power domains core code (Ulf Hansson, Geert Uytterhoeven). - Assorted minor fixes and cleanups of the device clocks control code in the PM core (Geert Uytterhoeven, Grygorii Strashko). - Consolidation of device power management Kconfig options by making CONFIG_PM_SLEEP select CONFIG_PM_RUNTIME and removing the latter which is now redundant (Rafael J Wysocki and Kevin Hilman). That is the first batch of the changes needed for this purpose. - Core device runtime power management support code cleanup related to the execution of callbacks (Andrzej Hajda). - cpuidle ARM support improvements (Lorenzo Pieralisi). - cpuidle cleanup related to the CPUIDLE_FLAG_TIME_VALID flag and a new MAINTAINERS entry for ARM Exynos cpuidle (Daniel Lezcano and Bartlomiej Zolnierkiewicz). - New cpufreq driver callback (->ready) to be executed when the cpufreq core is ready to use a given policy object and cpufreq-dt driver modification to use that callback for cooling device registration (Viresh Kumar). - cpufreq core fixes and cleanups (Viresh Kumar, Vince Hsu, James Geboski, Tomeu Vizoso). - Assorted fixes and cleanups in the cpufreq-pcc, intel_pstate, cpufreq-dt, pxa2xx cpufreq drivers (Lenny Szubowicz, Ethan Zhao, Stefan Wahren, Petr Cvek). - OPP (Operating Performance Points) framework modification to allow OPPs to be removed too and update of a few cpufreq drivers (cpufreq-dt, exynos5440, imx6q, cpufreq) to remove OPPs (added during initialization) on driver removal (Viresh Kumar). - Hibernation core fixes and cleanups (Tina Ruchandani and Markus Elfring). - PM Kconfig fix related to CPU power management (Pankaj Dubey). - cpupower tool fix (Prarit Bhargava)" * tag 'pm+acpi-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (120 commits) i2c-omap / PM: Drop CONFIG_PM_RUNTIME from i2c-omap.c dmaengine / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM tools: cpupower: fix return checks for sysfs_get_idlestate_count() drivers: sh / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM e1000e / igb / PM: Eliminate CONFIG_PM_RUNTIME MMC / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM MFD / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM misc / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM media / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM input / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM leds: leds-gpio: Fix multiple instances registration without 'label' property iio / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM hsi / OMAP / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM i2c-hid / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM drm / exynos / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM gpio / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM hwrandom / exynos / PM: Use CONFIG_PM in #ifdef block / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM USB / PM: Drop CONFIG_PM_RUNTIME from the USB core PM: Merge the SET*_RUNTIME_PM_OPS() macros ...
2014-12-08Merge tag 'mfd-for-linus-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfdLinus Torvalds3-0/+273
Pull MFD updates from Lee Jones: "Changes to the core: - Honour PLATFORM_DEVID_NONE and PLATFORM_DEVID_AUTO dev IDs Changes to existing drivers: - IRQ additions/fixes; axp20x, da9063-core - Code simplification; i2c-dln2 - Regmap additions/fixes; max77693 - Error checking/handling improvements; dln2, db8500-prcmu - Bug fixes; dln2, wm8350-core - DT support/documentation; max77693, max77686, tps65217, twl4030-power, gpio-tc3589x - Decouple syscon interface from platform devices - Use MFD hotplug registration; rtsx_usb, viperboard, hid-sensor-hub - Regulator fixups; sec-core - Power Management additions/fixes; rts5227, tc6393xb - Remove relic/redundant code; ab8500-sysctrl, lpc_sch, max77693-private - Clean-up/coding style changes; tps65090 - Clk additions/fixes; tc6393xb, tc6387xb, t7l66xb - Add USB-SPI support; dln2 - Trivial changes; max14577, arizona-spi, lpc_sch, wm8997-tables, wm5102-tables wm5110-tables, axp20x, atmel-hlcdc, rtsx_pci New drivers/supported devices: - axp288 PMIC support added to axp20x - s2mps13 support added to sec-core - New support for Diolan DLN-2 - New support for atmel-hlcdc" * tag 'mfd-for-linus-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd: (55 commits) mfd: rtsx: Add func to split u32 into register mfd: atmel-hlcdc: Add Kconfig option description and name mfd: da9063: Get irq base dynamically before registering device mfd: max14577: Fix obvious typo in company name in copyright mfd: axp20x: Constify axp20x_acpi_match and rid unused warning mfd: t7l66xb: prepare/unprepare clocks mfd: tc6387xb: prepare/unprepare clocks mfd: dln2: add support for USB-SPI module mfd: wm5110: Add missing registers for AIF2 channels 3-6 mfd: tc3589x: get rid of static base mfd: arizona: Document HP_CTRL_1L and HP_CTRL_1R registers mfd: wm8997: Mark INTERRUPT_STATUS_2_MASK as readable mfd: tc6393xb: Prepare/unprepare clocks mfd: tps65090: Fix bonkers indenting strategy mfd: tc6393xb: Fail ohci suspend if full state restore is required mfd: lpc_sch: Don't call mfd_remove_devices() mfd: wm8350-core: Fix probable mask then right shift defect mfd: ab8500-sysctrl: Drop ab8500_restart mfd: db8500-prcmu: Provide sane error path values mfd: db8500-prcmu: Check return of devm_ioremap for error ...
2014-12-08Merge branch 'pm-runtime'Rafael J. Wysocki3-4/+2
* pm-runtime: (25 commits) i2c-omap / PM: Drop CONFIG_PM_RUNTIME from i2c-omap.c dmaengine / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM drivers: sh / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM e1000e / igb / PM: Eliminate CONFIG_PM_RUNTIME MMC / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM MFD / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM misc / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM media / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM input / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM iio / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM hsi / OMAP / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM i2c-hid / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM drm / exynos / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM gpio / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM hwrandom / exynos / PM: Use CONFIG_PM in #ifdef block / PM: Replace CONFIG_PM_RUNTIME with CONFIG_PM USB / PM: Drop CONFIG_PM_RUNTIME from the USB core PM: Merge the SET*_RUNTIME_PM_OPS() macros PM / Kconfig: Do not select PM directly from Kconfig files PCI / PM: Drop CONFIG_PM_RUNTIME from the PCI core ...
2014-12-08Merge branches 'acpi-scan', 'acpi-pm', 'acpi-lpss' and 'acpi-processor'Rafael J. Wysocki1-0/+1
* acpi-scan: ACPI: Add _DEP support to fix battery issue on Asus T100TA * acpi-pm: ACPI / sleep: Drain outstanding events after disabling multiple GPEs ACPI / PM: Fixed a typo in a comment * acpi-lpss: dmaengine: dw: enable runtime PM ACPI / LPSS: introduce a 'proxy' device to power on LPSS for DMA ACPI / LPSS: allow to use specific PM domain during ->probe() ACPI / LPSS: add all LPSS devices to the specific power domain * acpi-processor: ACPI / cpuidle: avoid assigning signed errno to acpi_status ACPI / processor: remove unused variabled from acpi_processor_power structure ACPI / processor: Update the comments in processor.h
2014-12-05i2c-omap / PM: Drop CONFIG_PM_RUNTIME from i2c-omap.cRafael J. Wysocki1-2/+0
After commit b2b49ccbdd54 (PM: Kconfig: Set PM_RUNTIME if PM_SLEEP is selected) PM_RUNTIME is always set if PM is set, so some #ifdef blocks depending on CONFIG_PM_RUNTIME may be dropped now. Do that in drivers/i2c/busses/i2c-omap.c. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-04i2c: cadence: Set the hardware time-out register to maximum valueVishnu Motghare1-0/+11
Cadence I2C controller has bug wherein it generates invalid read transactions after timeout in master receiver mode. This driver does not use the HW timeout and this interrupt is disabled but the feature itself cannot be disabled. Hence, this patch writes the maximum value (0xFF) to this register. This is one of the workarounds to this bug and it will not avoid the issue completely but reduces the chances of error. Signed-off-by: Vishnu Motghare <vishnum@xilinx.com> Signed-off-by: Harini Katakam <harinik@xilinx.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2014-12-04i2c: davinci: generate STP always when NACK is receivedGrygorii Strashko1-5/+3
According to I2C specification the NACK should be handled as follows: "When SDA remains HIGH during this ninth clock pulse, this is defined as the Not Acknowledge signal. The master can then generate either a STOP condition to abort the transfer, or a repeated START condition to start a new transfer." [I2C spec Rev. 6, 3.1.6: http://www.nxp.com/documents/user_manual/UM10204.pdf] Currently the Davinci i2c driver interrupts the transfer on receipt of a NACK but fails to send a STOP in some situations and so makes the bus stuck until next I2C IP reset (idle/enable). For example, the issue will happen during SMBus read transfer which consists from two i2c messages write command/address and read data: S Slave Address Wr A Command Code A Sr Slave Address Rd A D1..Dn A P <--- write -----------------------> <--- read ---------------------> The I2C client device will send NACK if it can't recognize "Command Code" and it's expected from I2C master to generate STP in this case. But now, Davinci i2C driver will just exit with -EREMOTEIO and STP will not be generated. Hence, fix it by generating Stop condition (STP) always when NACK is received. This patch fixes Davinci I2C in the same way it was done for OMAP I2C commit cda2109a26eb ("i2c: omap: query STP always when NACK is received"). Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reported-by: Hein Tibosch <hein_tibosch@yahoo.es> Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2014-12-04i2c: davinci: switch to use platform_get_irqGrygorii Strashko1-8/+12
Switch Davinci I2C driver to use platform_get_irq(), because it is not recommened to use platform_get_resource(pdev, IORESOURCE_IRQ, ..) for requesting IRQ resources any more, as they can be not ready yet in case of DT-boot. Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-04i2c: sh_mobile: optimize irq entryWolfram Sang1-5/+4
We can simply pass the pointer to the private structure to the irq routine instead of passing the platform device and looking up its driver_data. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-04PM: Merge the SET*_RUNTIME_PM_OPS() macrosRafael J. Wysocki2-2/+2
The SET_PM_RUNTIME_PM_OPS() and SET_RUNTIME_PM_OPS() macros are identical except that one of them is not empty for CONFIG_PM set, while the other one is not empty for CONFIG_PM_RUNTIME set, respectively. However, after commit b2b49ccbdd54 (PM: Kconfig: Set PM_RUNTIME if PM_SLEEP is selected) PM_RUNTIME is always set if PM is set, so one of these macros is now redundant. For this reason, replace SET_PM_RUNTIME_PM_OPS() with SET_RUNTIME_PM_OPS() everywhere and redefine the SET_PM_RUNTIME_PM_OPS symbol as SET_RUNTIME_PM_OPS in case new code is starting to use the macro being removed here. Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-25i2c: pxa: add support for SCCB devicesPetr Cvek1-7/+12
Add support for SCCB by implementing I2C_M_IGNORE_NAK and I2C_M_STOP flags and advertising functionality flag I2C_FUNC_PROTOCOL_MANGLING. Also fixed missing functionality flag I2C_FUNC_NOSTART. Signed-off-by: Petr Cvek <petr.cvek@tul.cz> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-25omap: i2c: don't check bus state IP rev3.3 and earlierAlexander Kochetkov1-3/+5
Commit 0f5768bf894f ("i2c: omap: implement workaround for handling invalid BB-bit values") introduce the error result in boot test fault on OMAP3530 boards. The patch fix the error (disable i2c bus test for OMAP3530). Reported-by: Kevin Hilman <khilman@kernel.org> Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com> Fixes: 0f5768bf894f ("i2c: omap: implement workaround for handling invalid BB-bit values") Tested-by: Tony Lindgren <tony@atomide.com> Tested-by: Kevin Hilman <khilman@linaro.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-25i2c/of: Add OF_RECONFIG notifier handlerPantelis Antoniou1-0/+52
CONFIG_OF_DYNAMIC enables runtime changes to the device tree which in turn may trigger addition or removal of devices from Linux. Add an OF_RECONFIG notifier handler to receive tree change events and to creating or destroy i2c devices as required. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> [grant.likely: clean up #ifdefs and drop unneeded error handling] Signed-off-by: Grant Likely <grant.likely@linaro.org> Reviewed-by: Wolfram Sang <wsa@the-dreams.de> Cc: Rob Herring <robh+dt@kernel.org> Cc: linux-i2c@vger.kernel.org
2014-11-25i2c/of: Factor out Devicetree registration codePantelis Antoniou1-45/+52
Dynamically inserting i2c client device nodes requires the use of a single device registration method. Factor out the loop body of of_i2c_register_devices() so that it can be called for individual device_nodes instead of for all the children of a node. Note: The diff of this commit looks far more complicated than it actually is due the indentation being changed for a large block of code. When viewed using the diff -w flag to ignore whitespace changes it can be seen that the change is actually quite simple. Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> [grant.likely: Made new function static and removed changes to header] Signed-off-by: Grant Likely <grant.likely@linaro.org> Reviewed-by: Wolfram Sang <wsa@the-dreams.de> Cc: Rob Herring <robh+dt@kernel.org> Cc: linux-i2c@vger.kernel.org
2014-11-24i2c: s3c2410: Handle i2c sys_cfg register in i2c driverPankaj Dubey1-0/+29
Let's handle i2c interrupt re-configuration in i2c driver. This will help us in removing some soc specific checks from machine files and will help in removing static iomapping of SYS register in exynos.c Also handle saving and restoring of SYS_I2C_CFG register during suspend and resume of i2c driver. Signed-off-by: Pankaj Dubey <pankaj.dubey@samsung.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-24i2c: rk3x: add Kconfig dependency on COMMON_CLKMax Schwarz1-1/+1
Now that we are using the clk notifier framework we get compile errors without COMMON_CLK. But the driver fails to probe without COMMON_CLK anyways, so just add that as a Kconfig dependency. Signed-off-by: Max Schwarz <max.schwarz@online.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-24ACPI: Add _DEP support to fix battery issue on Asus T100TALan Tianyu1-0/+1
ACPI 5.0 introduces _DEP (Operation Region Dependencies) to designate device objects that OSPM should assign a higher priority in start ordering due to future operation region accesses. On Asus T100TA, ACPI battery info are read from a I2C slave device via I2C operation region. Before I2C operation region handler is installed, battery _STA always returns 0. There is a _DEP method of designating start order under battery device node. This patch is to implement _DEP feature to fix battery issue on the Asus T100TA. Introducing acpi_dep_list and adding dep_unmet count in struct acpi_device. During ACPI namespace scan, create struct acpi_dep_data for a valid pair of master (device pointed to by _DEP)/ slave(device with _DEP), record master's and slave's ACPI handle in it and put it into acpi_dep_list. The dep_unmet count will increase by one if there is a device under its _DEP. Driver's probe() should return EPROBE_DEFER when find dep_unmet is larger than 0. When I2C operation region handler is installed, remove all struct acpi_dep_data on the acpi_dep_list whose master is pointed to I2C host controller and decrease slave's dep_unmet. When dep_unmet decreases to 0, all _DEP conditions are met and then do acpi_bus_attach() for the device in order to resolve battery _STA issue on the Asus T100TA. Link: https://bugzilla.kernel.org/show_bug.cgi?id=69011 Tested-by: Jan-Michael Brummer <jan.brummer@tabos.org> Tested-by: Adam Williamson <adamw@happyassassin.net> Tested-by: Michael Shigorin <shigorin@gmail.com> Acked-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-23i2c: omap: add notes related to i2c multimaster modeAlexander Kochetkov1-1/+11
No functional changes. Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com> Reviewed-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-23i2c: omap: don't reset controller if Arbitration Lost detectedAlexander Kochetkov1-2/+4
Arbitration Lost is an expected situation in a multimaster environment. I2C controller (IP) correctly detect and report AL. The only one visible reason for resetting IP in the AL case is to avoid advisory 1.94 (omap3) and errata i595 (omap4): "I2C: After an Arbitration is Lost the Module Incorrectly Starts the Next Transfer". Errata workaround states: "The MST and STT bits inside I2C_CON should be set to 1 at the same moment (avoid setting the MST bit to 1 while STT = 0)." The driver never set MST and STT bits separately and doesn't create condition for errata. So the reset is not necessary. Also corrected return value for AL to -EAGAIN. Tested on Beagleboard XM C. Tested on BBB and AM437x Starter Kit by Felipe Balbi. Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com> Tested-by: Felipe Balbi <balbi@ti.com> Reviewed-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-23i2c: omap: implement workaround for handling invalid BB-bit valuesAlexander Kochetkov1-0/+103
In a multimaster environment, after IP software reset, BB-bit value doesn't correspond to the current bus state. It may happen what BB-bit will be 0, while the bus is busy due to another I2C master activity. Any transfer started when BB=0 and bus is busy wouldn't be completed by IP and results in controller timeout. More over, in some cases IP could interrupt another master's transfer and corrupt data on wire. The commit implement method allowing to prevent IP from entering into "controller timeout" state and from "data corruption" state. The one drawback is the need to wait for 10ms before the first transfer. Tested on Beagleboard XM C. Tested on BBB and AM437x Starter Kit by Felipe Balbi. Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com> Tested-by: Felipe Balbi <balbi@ti.com> Reviewed-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-23i2c: omap: cleanup register definitionsAlexander Kochetkov1-3/+7
Delete STAT_AD0 mask as unrelated to current IP (omap1?). Delete DEBUG conditional around SYSTEST masks group. Add SYSTEST functional mode masks for SCL and SDA. Add STAT_BF mask. Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com> Tested-by: Felipe Balbi <balbi@ti.com> Reviewed-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-23i2c: rk3x: handle dynamic clock rate changes correctlyMax Schwarz1-35/+118
The i2c input clock can change dynamically, e.g. on the RK3066 where pclk_i2c0 and pclk_i2c1 are connected to the armclk, which changes rate on cpu frequency scaling. Until now, we incorrectly called clk_get_rate() while holding the i2c->lock in rk3x_i2c_xfer() to adapt to clock rate changes. Thanks to Huang Tao for reporting this issue. Do it properly now using the clk notifier framework. The callback logic was taken from i2c-cadence.c. Also rename all misleading "i2c_rate" variables to "clk_rate", as they describe the *input* clk rate. Signed-off-by: Max Schwarz <max.schwarz@online.de> Tested-by: Doug Anderson <dianders@chromium.org> on RK3288 Reviewed-by: Doug Anderson <dianders@chromium.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-23i2c: at91: enable probe deferring on dma channel requestLudovic Desroches1-11/+14
If dma controller is not probed, defer i2c probe. Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-22i2c: omap: fix i207 errata handlingAlexander Kochetkov1-3/+5
commit 6d9939f651419a63e091105663821f9c7d3fec37 (i2c: omap: split out [XR]DR and [XR]RDY) changed the way how errata i207 (I2C: RDR Flag May Be Incorrectly Set) get handled. 6d9939f6514 code doesn't correspond to workaround provided by errata. According to errata ISR must filter out spurious RDR before data read not after. ISR must read RXSTAT to get number of bytes available to read. Because RDR could be set while there could no data in the receive FIFO. Restored pre 6d9939f6514 way of handling errata. Found by code review. Real impact haven't seen. Tested on Beagleboard XM C. Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com> Fixes: 6d9939f651419a63e09110 i2c: omap: split out [XR]DR and [XR]RDY Tested-by: Felipe Balbi <balbi@ti.com> Reviewed-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-21i2c: at91: remove legacy DMA supportArnd Bergmann1-34/+3
Since at91sam9g45 is now DT-only, all DMA capable users of this driver are using the DT case, and the legacy support can be removed. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-21i2c: designware: prevent early stop on TX FIFO emptyAndrew Jackson1-1/+1
If the Designware core is configured with IC_EMPTYFIFO_HOLD_MASTER_EN set to zero, allowing the TX FIFO to become empty causes a STOP condition to be generated on the I2C bus. If the transmit FIFO threshold is set too high, an erroneous STOP condition can be generated on long transfers - particularly where the interrupt latency is extended. Signed-off-by: Andrew Jackson <Andrew.Jackson@arm.com> Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-21i2c: omap: fix NACK and Arbitration Lost irq handlingAlexander Kochetkov1-2/+0
commit 1d7afc95946487945cc7f5019b41255b72224b70 (i2c: omap: ack IRQ in parts) changed the interrupt handler to complete transfers without clearing XRDY (AL case) and ARDY (NACK case) flags. XRDY or ARDY interrupts will be fired again. As a result, ISR keep processing transfer after it was already complete (from the driver code point of view). A didn't see real impacts of the 1d7afc9, but it is really bad idea to have ISR running on user data after transfer was complete. It looks, what 1d7afc9 violate TI specs in what how AL and NACK should be handled (see Note 1, sprugn4r, Figure 17-31 and Figure 17-32). According to specs (if I understood correctly), in case of NACK and AL driver must reset NACK, AL, ARDY, RDR, and RRDY (Master Receive Mode), and NACK, AL, ARDY, and XDR (Master Transmitter Mode). All that is done down the code under the if condition: if (stat & (OMAP_I2C_STAT_ARDY | OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) ... The patch restore pre 1d7afc9 logic of handling NACK and AL interrupts, so no interrupts is fired after ISR informs the rest of driver what transfer complete. Note: instead of removing break under NACK case, we could just replace 'break' with 'continue' and allow NACK transfer to finish using ARDY event. I found that NACK and ARDY bits usually set together. That case confirm TI wiki: http://processors.wiki.ti.com/index.php/I2C_Tips#Detecting_and_handling_NACK In order if someone interested in the event traces for NACK and AL cases, I sent them to mailing list. Tested on Beagleboard XM C. Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com> Fixes: 1d7afc9 i2c: omap: ack IRQ in parts Cc: <stable@vger.kernel.org> # v3.7+ Acked-by: Felipe Balbi <balbi@ti.com> Tested-by: Aaro Koskinen <aaro.koskinen@iki.fi> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-19i2c: dln2: Simplify return flow for dln2_i2c_enableOctavian Purdila1-6/+1
This fixes the following kbuild test robot warning: >> drivers/i2c/busses/i2c-dln2.c:70:1-4: WARNING: end returns can be simplified if negative or 0 value Reported-by: kbuild test robot <fengguang.wu@intel.com> Reported-by: Julia Lawall <julia.lawall@lip6.fr> Signed-off-by: Octavian Purdila <octavian.purdila@intel.com> Acked-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Lee Jones <lee.jones@linaro.org>
2014-11-19i2c: sh_mobile: use proper device for mapping DMA memoryWolfram Sang1-9/+14
It should be the DMA device, not the platform device. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-19i2c: imx: simplify i2c_imx_dma_write() a littleWolfram Sang1-5/+1
Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Yao Yuan <yao.yuan@freescale.com>