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2015-03-09i2c: i801: Remove i801_driver forward declarationJarkko Nikula
struct pci_driver i801_driver forward declaration is needed only for accessing the name field. Remove it and use dev_driver_string() instead. 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>
2015-03-09i2c: i801: Don't break user-visible stringsJarkko Nikula
It makes more difficult to grep these error prints from sources if they are split to multiple source lines. 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>
2015-03-07i2c: designware-baytrail: baytrail_i2c_acquire() might sleepAndy Shevchenko
This patch marks baytrail_i2c_acquire() that it might sleep. Also it chages while-loop to do-while and, though it is matter of taste, gives a chance to check one more time before report a timeout. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: David E. Box <david.e.box@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-03-07i2c: designware-baytrail: cross-check lock functionsAndy Shevchenko
It seems the idea behind the cross-check is to prevent acquire semaphore when there is no release callback and vice versa. Thus, patch fixes a typo. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: David E. Box <david.e.box@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-03-07i2c: designware-baytrail: fix sparse warningsAndy Shevchenko
There is no need to export functions that are used as the callbacks in the struct dw_i2c_dev. Otherwise we get the following warnings: drivers/i2c/busses/i2c-designware-baytrail.c:63:5: warning: symbol 'baytrail_i2c_acquire' was not declared. Should it be static? drivers/i2c/busses/i2c-designware-baytrail.c:114:6: warning: symbol 'baytrail_i2c_release' was not declared. Should it be static? While here, do few indentation fixes, remove i2c_dw_eval_lock_support() from functions exported to the modules and redundant assignment of local sem variable. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: David E. Box <david.e.box@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-03-07i2c: designware-baytrail: fix typo in error pathAndy Shevchenko
It seems we have same message for different return values in get_sem() and baytrail_i2c_acquire(). I suspect this is just a typo, so this patch fixes it. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: David E. Box <david.e.box@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-03-07i2c: designware-baytrail: describe magic numbersAndy Shevchenko
The patch converts hardcoded numerical constants to a named ones. While here, align the variable name in get_sem() and reset_semaphore(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: David E. Box <david.e.box@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-02-26mfd: cros_ec: Use fixed size arrays to transfer data with the ECJavier Martinez Canillas
The struct cros_ec_command will be used as an ioctl() argument for the API to control the ChromeOS EC from user-space. So the data structure has to be 64-bit safe to make it compatible between 32 and 64 avoiding the need for a compat ioctl interface. Since pointers are self-aligned to different byte boundaries, use fixed size arrays instead of pointers for transferring ingoing and outgoing data with the Embedded Controller. Also, re-arrange struct members by decreasing alignment requirements to reduce the needing padding size. Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk> Acked-by: Lee Jones <lee.jones@linaro.org> Tested-by: Gwendal Grignou <gwendal@chromium.org> Reviewed-by: Gwendal Grignou <gwendal@chromium.org> Signed-off-by: Olof Johansson <olof@lixom.net>
2015-02-21Merge branch 'i2c/for-3.20' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux Pull i2c updates from Wolfram Sang: "Summary: - legacy PM code removed from the core, there were no users anymore (thanks to Lars-Peter Clausen) - new driver for Broadcom iProc - bigger driver updates for designware, rk3x, cadence, ocores - a bunch of smaller updates and bugfixes" * 'i2c/for-3.20' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (31 commits) i2c: ocores: rework clk code to handle NULL cookie i2c: designware-baytrail: another fixup for proper Kconfig dependencies i2c: fix reference to functionality constants definition i2c: iproc: Add Broadcom iProc I2C Driver i2c: designware-pci: update Intel copyright line i2c: ocores: add common clock support i2c: hix5hd2: add COMPILE_TEST i2c: clarify comments about the dev_released completion i2c: ocores: fix clock-frequency binding usage i2c: tegra: Maintain CPU endianness i2c: designware-baytrail: use proper Kconfig dependencies i2c: designware: Do not calculate SCL timing parameters needlessly i2c: do not try to load modules for of-registered devices i2c: designware: Add Intel Baytrail PMIC I2C bus support i2c: designware: Add i2c bus locking support of: i2c: Add i2c-mux-idle-disconnect DT property to PCA954x mux driver i2c: designware: use {readl|writel}_relaxed instead of readl/writel i2c: designware-pci: no need to provide clk_khz i2c: designware-pci: remove Moorestown support i2c: imx: whitespace and checkpatch cleanup ...
2015-02-20i2c: ocores: rework clk code to handle NULL cookieWolfram Sang
For, !HAVE_CLK the clk API returns a NULL cookie. Rework the initialization code to handle that. If clk_get_rate() delivers 0, we use the fallback mechanisms. The patch is pretty easy when ignoring white space issues (git diff -b). Suggested-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Tested-by: Max Filippov <jcmvbkbc@gmail.com>
2015-02-19i2c: designware-baytrail: another fixup for proper Kconfig dependenciesWolfram Sang
IOSF_MBI is tristate. Baytrail driver isn't. Reported-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: David E. Box <david.e.box@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-02-17i2c: iproc: Add Broadcom iProc I2C DriverRay Jui
Add initial support to the Broadcom iProc I2C controller found in the iProc family of SoCs. The iProc I2C controller has separate internal TX and RX FIFOs, each has a size of 64 bytes. The iProc I2C controller supports two bus speeds including standard mode (100kHz) and fast mode (400kHz) Signed-off-by: Ray Jui <rjui@broadcom.com> Reviewed-by: Scott Branden <sbranden@broadcom.com> Reviewed-by: Kevin Cernekee <cernekee@chromium.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-02-17i2c: designware-pci: update Intel copyright lineAndy Shevchenko
While here, fix few indentations issues across the code. There is no functional change. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-02-05i2c: ocores: add common clock supportMax Filippov
Allow bus clock specification as a common clock handle. This makes this controller easier to use in a setup based on common clock framework. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-02-05i2c: hix5hd2: add COMPILE_TESTZhangfei Gao
Commit 9439eb3ab9d1ec ("asm-generic: io: implement relaxed accessor macros as conditional wrappers") has added {read,write}{b,w,l,q}_relaxed to include/asm-generic/io.h. So COMPILE_TEST can be added. Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-02-05i2c: ocores: fix clock-frequency binding usageMax Filippov
clock-frequency property is meant to control the bus frequency for i2c bus drivers, but it was incorrectly used to specify i2c controller input clock frequency. Introduce new attribute, opencores,ip-clock-frequency, that specifies i2c controller clock frequency and make clock-frequency attribute compatible with other i2c drivers. Maintain backwards compatibility in case opencores,ip-clock-frequency attribute is missing. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-30i2c: sh_mobile: terminate DMA reads properlyWolfram Sang
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 Delvare
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>
2015-01-26i2c: tegra: Maintain CPU endiannessDmitry Osipenko
Support CPU BE mode by adding endianness conversion for memcpy interactions. Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Acked-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-26i2c: designware-baytrail: use proper Kconfig dependenciesWolfram Sang
IOSF_MBI depends on PCI, so we should not select it but depend on it. This ensures also we compile on X86 only, other archs will break because of an arch specific include. Also depend on ACPI since this driver uses it. Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: David E. Box <david.e.box@linux.intel.com>
2015-01-26i2c: designware: Do not calculate SCL timing parameters needlesslyJarkko Nikula
Do SCL timing parameter calculation conditionally depending are custom parameters provided since calculated values will get instantly overwritten by provided parameters. Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-26i2c: designware: Add Intel Baytrail PMIC I2C bus supportDavid Box
This patch implements an I2C bus sharing mechanism between the host and platform hardware on select Intel BayTrail SoC platforms using the X-Powers AXP288 PMIC. On these platforms access to the PMIC must be shared with platform hardware. The hardware unit assumes full control of the I2C bus and the host must request access through a special semaphore. Hardware control of the bus also makes it necessary to disable runtime pm to avoid interfering with hardware transactions. Signed-off-by: David E. Box <david.e.box@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-26i2c: designware: Add i2c bus locking supportDavid Box
Adds support for acquiring and releasing a hardware bus lock in the i2c designware core transfer function. This is needed for i2c bus controllers that are shared with but not controlled by the kernel. Signed-off-by: David E. Box <david.e.box@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-24i2c: s3c2410: fix ABBA deadlock by keeping clock preparedPaul Osmialowski
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
2015-01-23i2c: designware: use {readl|writel}_relaxed instead of readl/writelJisheng Zhang
readl/writel is too expensive especially on Cortex A9 w/ outer L2 cache. This introduces i2c read/write delays on Marvell BG2/BG2Q SoCs when there are heavy L2 cache maintenance operations at the same time. The driver does not perform DMA, so it's safe to use the relaxed version. From another side, the relaxed io accessor macros are available on all architectures now, so we can use the relaxed versions instead. Signed-off-by: Jisheng Zhang <jszhang@marvell.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-23i2c: designware-pci: no need to provide clk_khzAndy Shevchenko
The clk_khz field makes sense only if SS counters are not provided. Since we provide them for Haswell and Baytrail explicitly we may omit the clk_khz parameter. Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-23i2c: designware-pci: remove Moorestown supportAndy Shevchenko
The Moorestown support bits were removed few years ago. This is a follow up to that changes. Suggested-by: David Cohen <david.a.cohen@linux.intel.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-22i2c: imx: whitespace and checkpatch cleanupPhilipp Zabel
This patch fixes up some whitespace issues and addresses a few checkpatch warnings. Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de> Acked-by: Fugang Duan <B38611@freescale.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-14i2c: imx: remove unused return value assignmentsPhilipp Zabel
The ret variable is set and never used in the error path of i2c_imx_dma_request. Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de> Acked-by: Fugang Duan <B38611@freescale.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-14i2c: cadence: Check for errata condition involving master receiveHarini Katakam
Cadence I2C controller has the following bugs: - completion indication is not given to the driver at the end of a read/receive transfer with HOLD bit set. - Invalid read transaction are generated on the bus when HW timeout condition occurs with HOLD bit set. As a result of the above, if a set of messages to be transferred with repeated start includes any message following a read message, completion is never indicated and timeout occurs. Hence a check is implemented to return -EOPNOTSUPP for such sequences. Signed-off-by: Harini Katakam <harinik@xilinx.com> Signed-off-by: Vishnu Motghare <vishnum@xilinx.com> [wsa: fixed some whitespaces] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-13i2c: imx: fix handling of wait_for_completion_timeout resultNicholas Mc Guire
wait_for_completion_timeout does not return negative values so "result" handling here should be simplified to cover the actually possible cases only. Signed-off-by: Nicholas Mc Guire <der.herr@hofr.at> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-13i2c: rk3x: Account for repeated start time requirementDoug Anderson
On Rockchip I2C the controller drops SDA low slightly too soon to meet the "repeated start" requirements. >From my own experimentation over a number of rates: - controller appears to drop SDA at .875x (7/8) programmed clk high. - controller appears to keep SCL high for 2x programmed clk high. The first rule isn't enough to meet tSU;STA requirements in Standard-mode on the system I tested on. The second rule is probably enough to meet tHD;STA requirements in nearly all cases (especially after accounting for the first), but it doesn't hurt to account for it anyway just in case. Even though the repeated start requirement only need to be accounted for during a small part of the transfer, we'll adjust the timings for the whole transfer to meet it. I believe that adjusting the timings in just the right place to switch things up for repeated start would require several extra interrupts and that doesn't seem terribly worth it. With this change and worst case rise/fall times, I see 100kHz i2c going to ~85kHz. With slightly optimized rise/fall (800ns / 50ns) I see i2c going to ~89kHz. Fast-mode isn't affected much because tSU;STA is shorter relative to tHD;STA there. As part of this change we needed to account for the SDA falling time. The specification indicates that this should be the same, but we'll follow Designware's lead and add a binding. Note that we deviate from Designware and assign the default SDA falling time to be the same as the SCL falling time, which is incredibly likely. Signed-off-by: Doug Anderson <dianders@chromium.org> [wsa: rebased to i2c/for-next] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-13i2c: rk3x: fix bug that cause measured high_ns doesn't meet I2C specificationaddy ke
The number of clock cycles to be written into the CLKDIV register that determines the I2C clk high phase includes the rise time. So to meet the timing requirements defined in the I2C specification which defines the minimal time SCL has to be high, the rise time has to taken into account. The same applies to the low phase with falling time. In my test on RK3288-Pink2 board, which is not an upstream board yet, if external pull-up resistor is 4.7K, rise_ns is about 700ns. So the measured high_ns is about 3900ns, which is less than 4000ns (the minimum high_ns in I2C specification for Standard-mode). To fix this bug min_low_ns should include fall time and min_high_ns should include rise time. This patch merged the patch from chromium project which can get the rise and fall times for signals from the device tree. This allows us to more accurately calculate timings. see: https://chromium-review.googlesource.com/#/c/232774/ Signed-off-by: Addy Ke <addy.ke@rock-chips.com> Reviewed-by: Doug Anderson <dianders@chromium.org> Tested-by: Doug Anderson <dianders@chromium.org> [wsa: fixed a typo in the docs] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-13i2c: cadence: Handle > 252 byte transfersHarini Katakam
The I2C controller sends a NACK to the slave when transfer size register reaches zero, irrespective of the hold bit. So, in order to handle transfers greater than 252 bytes, the transfer size register has to be maintained at a value >= 1. This patch implements the same. The interrupt status is cleared at the beginning of the isr instead of the end, to avoid missing any interrupts. Signed-off-by: Harini Katakam <harinik@xilinx.com> [wsa: added braces around else branch] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-13i2c: pmcmsp: remove dead codeWolfram Sang
CPPCHECK rightfully says: drivers/i2c/busses/i2c-pmcmsp.c:151: style: The function 'pmcmsptwi_reg_to_clock' is never used. Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-20Merge branch 'i2c/for-next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 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 Sang
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 ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux 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 Uytterhoeven
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 Sang
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 Sang
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 Petazzoni
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 Petazzoni
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 ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core 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 ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 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 Gupta
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 Sang
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 Sang
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>
2014-12-10Merge tag 'pm+acpi-3.19-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm 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 ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd 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 ...