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path: root/drivers/spi/spi.c
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2017-04-26Merge remote-tracking branches 'spi/topic/ti-qspi' and 'spi/topic/xlp' into ↵Mark Brown
spi-next
2017-04-26Merge remote-tracking branches 'spi/topic/devprop', 'spi/topic/fsl', ↵Mark Brown
'spi/topic/fsl-dspi', 'spi/topic/imx' and 'spi/topic/lantiq' into spi-next
2017-04-26Merge remote-tracking branch 'spi/topic/core' into spi-nextMark Brown
2017-04-21spi: Add can_dma like interface for spi_flash_readVignesh R
Add an interface analogous to ->can_dma() for spi_flash_read() interface. This will enable SPI controller drivers to inform SPI core when not to do DMA mappings. Signed-off-by: Vignesh R <vigneshr@ti.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-04-18spi: double time out toleranceHauke Mehrtens
The generic SPI code calculates how long the issued transfer would take and adds 100ms in addition to the timeout as tolerance. On my 500 MHz Lantiq Mips SoC I am getting timeouts from the SPI like this when the system boots up: m25p80 spi32766.4: SPI transfer timed out blk_update_request: I/O error, dev mtdblock3, sector 2 SQUASHFS error: squashfs_read_data failed to read block 0x6e After increasing the tolerance for the timeout to 200ms I haven't seen these SPI transfer time outs any more. The Lantiq SPI driver in use here has an extra work queue in between, which gets triggered when the controller send the last word and the hardware FIFOs used for reading and writing are only 8 words long. Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-03-06spi: allow registering empty spi_board_info listsDmitry Torokhov
Many boards form list of spi_board_info entries depending on config, and it is possible to end up with empty list. Do not report error in such cases. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-03-06spi: allow attaching device properties to SPI board infoDmitry Torokhov
Generic device properties support statically defined property sets. For them to be usable, we need to attach these property sets before devices are registered and probed. Allowing to attach property list to spi_board_info structure will allow non-ACPI non-DT boards switch to using generic properties and get rid of custom platform data. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar
<uapi/linux/sched/types.h> We are going to move scheduler ABI details to <uapi/linux/sched/types.h>, which will be used from a number of .c files. Create empty placeholder header that maps to <linux/types.h>. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-20Merge tag 'acpi-4.11-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI updates from Rafael Wysocki: "These update the ACPICA code in the kernel to upstream revision 20170119, which among other things updates copyright notices in all of the ACPICA files, fix a couple of issues in the ACPI EC and button drivers, fix modalias handling for non-discoverable devices with DT-compatible identification strings, add a suspend quirk for one platform and fix a message in the APEI code. Specifics: - Update of the ACPICA code in the kernel to upstream revision 20170119 including: + Fixes related to the handling of the bit width and bit offset fields in Generic Address Structure (Lv Zheng) + ACPI resources handling fix related to invalid resource descriptors (Bob Moore) + Fix to enable implicit result conversion for several ASL library functions (Bob Moore) + Support for method invocations as target operands in AML (Bob Moore) + Fix to use a correct operand type for DeRefOf() in some situations (Bob Moore) + Utilities updates (Bob Moore, Lv Zheng) + Disassembler/debugger updates (David Box, Lv Zheng) + Build fixes (Colin Ian King, Lv Zheng) + Update of copyright notices in all files (Bob Moore) - Fix for modalias handling for SPI and I2C devices with DT-compatible identification strings (Dan O'Donovan) - Fixes for the ACPI EC and button drivers (Lv Zheng) - ACPI processor handling fix related to CPU hotplug (online/offline) on x86 (Vitaly Kuznetsov) - Suspend quirk to save/restore NVS memory over S3 transitions for Lenovo G50-45 (Zhang Rui) - Message formatting fix for the ACPI APEI code (Colin Ian King)" * tag 'acpi-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (32 commits) ACPICA: Update version to 20170119 ACPICA: Tools: Update common signon, remove compilation bit width ACPICA: Source tree: Update copyright notices to 2017 ACPICA: Linuxize: Restore and fix Intel compiler build x86/ACPI: keep x86_cpu_to_acpiid mapping valid on CPU hotplug spi: acpi: Initialize modalias from of_compatible i2c: acpi: Initialize info.type from of_compatible ACPI / bus: Introduce acpi_of_modalias() equiv of of_modalias_node() ACPI: save NVS memory for Lenovo G50-45 ACPI, APEI, EINJ: fix malformed newline escape ACPI / button: Remove lid_init_state=method mode ACPI / button: Change default behavior to lid_init_state=open ACPI / EC: Use busy polling mode when GPE is not enabled ACPI / EC: Remove old CLEAR_ON_RESUME quirk ACPICA: Update version to 20161222 ACPICA: Parser: Update parse info table for some operators ACPICA: Fix a problem with recent extra support for control method invocations ACPICA: Parser: Allow method invocations as target operands ACPICA: Fix for implicit result conversion for the ToXXX functions ACPICA: Resources: Not a valid resource if buffer length too long ..
2017-02-19Merge remote-tracking branches 'spi/topic/rockchip', 'spi/topic/rspi', ↵Mark Brown
'spi/topic/s3c64xx', 'spi/topic/sh-msiof' and 'spi/topic/slave' into spi-next
2017-02-19Merge remote-tracking branch 'spi/topic/dma' into spi-nextMark Brown
2017-02-07spi: acpi: Initialize modalias from of_compatibleDan O'Donovan
When using devicetree spi_device.modalias is set to the compatible string with the vendor prefix removed. For SPI devices described via ACPI the spi_device.modalias string is initialized by acpi_device_hid. When using ACPI and DT ids this string ends up something like "PRP0001". Change acpi_register_spi_device to use the of_compatible property if present. This makes it easier to instantiate spi drivers through ACPI with DT ids. Signed-off-by: Dan O'Donovan <dan@emutex.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Acked-by: Mark Brown <broonie@kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-01-31spi: fix device-node leaksJohan Hovold
Make sure to release the device-node reference taken in of_register_spi_device() on errors and when deregistering the device. Fixes: 284b01897340 ("spi: Add OF binding support for SPI busses") Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-01-31spi: When no dma_chan map buffers with spi_master's parentDaniel Kurtz
Back before commit 1dccb598df54 ("arm64: simplify dma_get_ops"), for arm64, devices for which dma_ops were not explicitly set were automatically configured to use swiotlb_dma_ops, since this was hard-coded as the global "dma_ops" in arm64_dma_init(). Now that global "dma_ops" has been removed, all devices much have their dma_ops explicitly set by a call to arch_setup_dma_ops(), otherwise the device is assigned dummy_dma_ops, and thus calls to map_sg for such a device will fail (return 0). Mediatek SPI uses DMA but does not use a dma channel. Support for this was added by commit c37f45b5f1cd ("spi: support spi without dma channel to use can_dma()"), which uses the master_spi dev to DMA map buffers. The master_spi device is not a platform device, rather it is created in spi_alloc_device(), and therefore its dma_ops are never set. Therefore, when the mediatek SPI driver when it does DMA (for large SPI transactions > 32 bytes), SPI will use spi_map_buf()->dma_map_sg() to map the buffer for use in DMA. But dma_map_sg()->dma_map_sg_attrs() returns 0, because ops->map_sg is dummy_dma_ops->__dummy_map_sg, and hence spi_map_buf() returns -ENOMEM (-12). Fix this by using the real spi_master's parent device which should be a real physical device with DMA properties. Signed-off-by: Daniel Kurtz <djkurtz@chromium.org> Fixes: c37f45b5f1cd ("spi: support spi without dma channel to use can_dma()") Cc: Leilk Liu <leilk.liu@mediatek.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-01-17spi: Use kcalloc() in spi_register_board_info()Markus Elfring
A multiplication for the size determination of a memory allocation indicated that an array data structure should be processed. Thus reuse the corresponding function "kcalloc". This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-12-15spi: core: Extract of_spi_parse_dt()Geert Uytterhoeven
Extract the parsing of SPI slave-specific properties into its own function, so it can be reused later for SPI slave controllers. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-12-12Merge remote-tracking branches 'spi/topic/delay', 'spi/topic/dw', ↵Mark Brown
'spi/topic/fsl-dspi' and 'spi/topic/fsl-espi' into spi-next
2016-12-12Merge remote-tracking branch 'spi/topic/dma' into spi-nextMark Brown
2016-12-12Merge remote-tracking branch 'spi/topic/core' into spi-nextMark Brown
2016-11-22spi: use sg_next for walking through the allocated scatterlist tableJuan Gutierrez
A null dereference or Oops exception might occurs when reading at once the whole content of an spi-nor of big enough size that requires an scatterlist table that does not fit into one single page. The spi_map_buf function is ignoring the chained sg case by dereferenceing the scatterlist elements in an array fashion. This wrongly assumes that the allocation of the scatterlist elements are contiguous. This is true as long as the scatterlist table fits within a PAGE_SIZE. However, for allocation where the scatter table is bigger than that, the pages allocated by sg_alloc might not be contigous. The sg table can be properly walked by sg_next instead of using an array. Signed-off-by: Juan Gutierrez <juan.gutierrez@nxp.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-10-26spi: change post transfer udelay() to usleep_range() for long delaysDaniel Kurtz
The spi_transfer parameter delay_usecs allows specifying a time to wait after transferring a spi message. This wait can be quite long - some devices, such as some Chrome OS ECs, require as much as 2000 usecs after a SPI transaction, before it can respond. (cf: arch/arm64/boot/dts/nvidia/tegra132-norrin.dts: google,cros-ec-spi-msg-delay = <2000> ) Blocking a CPU for 2 msecs in a busy loop like this doesn't seem very friendly to other processes, so change the blocking delay to a sleep to allow other things to use this CPU (or so it can sleep). This should be safe to do, because: (a) A post-transaction delay like this is always specified as a minimum wait time (b) A delay here is most likely not very time sensitive, as it occurs after all data has been transferred (c) This delay occurs in a non-critical section of the spi worker thread so where it is safe to sleep. Two caveats: 1) To avoid penalizing short delays, still use udelay for delays < 10us. 2) usleep_range() very often picks the upper bound, an upper bounds 10% should be plenty. Signed-off-by: Daniel Kurtz <djkurtz@chromium.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-10-24spi: mark device nodes only in case of successful instantiationRalf Ramsauer
Instantiated SPI device nodes are marked with OF_POPULATE. This was introduced in bd6c164. On unloading, loaded device nodes will of course be unmarked. The problem are nodes that fail during initialisation: If a node fails, it won't be unloaded and hence not be unmarked. If a SPI driver module is unloaded and reloaded, it will skip nodes that failed before. Skip device nodes that are already populated and mark them only in case of success. Note that the same issue exists for I2C. Fixes: bd6c164 ("spi: Mark instantiated device nodes with OF_POPULATE") Signed-off-by: Ralf Ramsauer <ralf@ramses-pyramidenbau.de> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Signed-off-by: Mark Brown <broonie@kernel.org> Cc: stable@vger.kernel.org
2016-10-21spi: Add Flag to Enable Slave Select with GPIO Chip Select.Thor Thayer
Some SPI masters require slave selection before the transfer can begin [1]. The SPI framework currently selects the chip using either 1) the internal CS mechanism or 2) the GPIO CS, but not both. This patch adds a new master->flags define to indicate both the GPIO CS and the internal chip select mechanism should be used. Tested On: Altera CycloneV development kit Compile tested for build errors on x86_64 (allyesconfigs) [1] DesignWare dw_apb_ssi Databook, Version 3.20a (page 39) Signed-off-by: Thor Thayer <tthayer@opensource.altera.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-10-11kthread: kthread worker API cleanupPetr Mladek
A good practice is to prefix the names of functions by the name of the subsystem. The kthread worker API is a mix of classic kthreads and workqueues. Each worker has a dedicated kthread. It runs a generic function that process queued works. It is implemented as part of the kthread subsystem. This patch renames the existing kthread worker API to use the corresponding name from the workqueues API prefixed by kthread_: __init_kthread_worker() -> __kthread_init_worker() init_kthread_worker() -> kthread_init_worker() init_kthread_work() -> kthread_init_work() insert_kthread_work() -> kthread_insert_work() queue_kthread_work() -> kthread_queue_work() flush_kthread_work() -> kthread_flush_work() flush_kthread_worker() -> kthread_flush_worker() Note that the names of DEFINE_KTHREAD_WORK*() macros stay as they are. It is common that the "DEFINE_" prefix has precedence over the subsystem names. Note that INIT() macros and init() functions use different naming scheme. There is no good solution. There are several reasons for this solution: + "init" in the function names stands for the verb "initialize" aka "initialize worker". While "INIT" in the macro names stands for the noun "INITIALIZER" aka "worker initializer". + INIT() macros are used only in DEFINE() macros + init() functions are used close to the other kthread() functions. It looks much better if all the functions use the same scheme. + There will be also kthread_destroy_worker() that will be used close to kthread_cancel_work(). It is related to the init() function. Again it looks better if all functions use the same naming scheme. + there are several precedents for such init() function names, e.g. amd_iommu_init_device(), free_area_init_node(), jump_label_init_type(), regmap_init_mmio_clk(), + It is not an argument but it was inconsistent even before. [arnd@arndb.de: fix linux-next merge conflict] Link: http://lkml.kernel.org/r/20160908135724.1311726-1-arnd@arndb.de Link: http://lkml.kernel.org/r/1470754545-17632-3-git-send-email-pmladek@suse.com Suggested-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Petr Mladek <pmladek@suse.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Borislav Petkov <bp@suse.de> Cc: Michal Hocko <mhocko@suse.cz> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-11spi: Add Flag to Enable Slave Select with GPIO Chip Select.Thor Thayer
Some SPI masters require slave selection before the transfer can begin [1]. The SPI framework currently selects the chip using either 1) the internal CS mechanism or 2) the GPIO CS, but not both. This patch adds a new master->flags define to indicate both the GPIO CS and the internal chip select mechanism should be used. Tested On: Altera CycloneV development kit Compile tested for build errors on x86_64 (allyesconfigs) [1] DesignWare dw_apb_ssi Databook, Version 3.20a (page 39) Signed-off-by: Thor Thayer <tthayer@opensource.altera.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-09-30Merge remote-tracking branch 'spi/topic/dma' into spi-nextMark Brown
2016-09-06Merge remote-tracking branches 'spi/fix/lock', 'spi/fix/maintainers', ↵Mark Brown
'spi/fix/put', 'spi/fix/pxa2xx', 'spi/fix/sh-msiof' and 'spi/fix/timeout' into spi-linus
2016-09-03spi: Prevent unexpected SPI time out due to arithmetic overflowSien Wu
When reading SPI flash as MTD device, the transfer length is directly passed to the spi driver. If the requested data size exceeds 512KB, it will cause the time out calculation to overflow since transfer length is 32-bit unsigned integer. This issue is resolved by using 64-bit unsigned integer to perform the arithmetic. Signed-off-by: Sien Wu <sien.wu@ni.com> Acked-by: Brad Keryan <brad.keryan@ni.com> Acked-by: Gratian Crisan <gratian.crisan@ni.com> Acked-by: Brad Mouring <brad.mouring@ni.com> Natinst-ReviewBoard-ID 150232 Signed-off-by: Mark Brown <broonie@kernel.org>
2016-08-17spi: Add support to handle kmap'd buffers in spi_map_buf()Vignesh R
JFFS2 FS might sometime provide kmap'd buffers as destination buffers to read data from flash. Update spi_map_buf() function to generate sg_list for such buffers, so that SPI controllers drivers can use DMA to read data into such buffers. Signed-off-by: Vignesh R <vigneshr@ti.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-08-09spi: Drop io_mutex in error pathsMark Brown
A couple of error paths were missing drops of io_mutex. Reported-by: Julia Lawall <julia.lawall@lip6.fr> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-07-27Merge tag 'spi-v4.8' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi Pull spi updates from Mark Brown: "Quite a lot of cleanup and maintainence work going on this release in various drivers, and also a fix for a nasty locking issue in the core: - A fix for locking issues when external drivers explicitly locked the bus with spi_bus_lock() - we were using the same lock to both control access to the physical bus in multi-threaded I/O operations and exclude multiple callers. Confusion between these two caused us to have scenarios where we were dropping locks. These are fixed by splitting into two separate locks like should have been done originally, making everything much clearer and correct. - Support for DMA in spi_flash_read(). - Support for instantiating spidev on ACPI systems, including some test devices used in Windows validation. - Use of the core DMA mapping functionality in the McSPI driver. - Start of support for ThunderX SPI controllers, involving a very big set of changes to the Cavium driver. - Support for Braswell, Exynos 5433, Kaby Lake, Merrifield, RK3036, RK3228, RK3368 controllers" * tag 'spi-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (64 commits) spi: Split bus and I/O locking spi: octeon: Split driver into Octeon specific and common parts spi: octeon: Move include file from arch/mips to drivers/spi spi: octeon: Put register offsets into a struct spi: octeon: Store system clock freqency in struct octeon_spi spi: octeon: Convert driver to use readq()/writeq() functions spi: pic32-sqi: fixup wait_for_completion_timeout return handling spi: pic32: fixup wait_for_completion_timeout return handling spi: rockchip: limit transfers to (64K - 1) bytes spi: xilinx: Return IRQ_NONE if no interrupts were detected spi: xilinx: Handle errors from platform_get_irq() spi: s3c64xx: restore removed comments spi: s3c64xx: add Exynos5433 compatible for ioclk handling spi: s3c64xx: use error code from clk_prepare_enable() spi: s3c64xx: rename goto labels to meaningful names spi: s3c64xx: document the clocks and the clock-name property spi: s3c64xx: add exynos5433 spi compatible spi: s3c64xx: fix reference leak to master in s3c64xx_spi_remove() spi: spi-sh: Remove deprecated create_singlethread_workqueue spi: spi-topcliff-pch: Remove deprecated create_singlethread_workqueue ...
2016-07-25spi: Split bus and I/O lockingMark Brown
The current SPI code attempts to use bus_lock_mutex for two purposes. One is to implement spi_bus_lock() which grants exclusive access to the bus. The other is to serialize access to the physical hardware. This duplicate purpose causes confusion which leads to cases where access is not locked when a caller holds the bus lock mutex. Fix this by splitting out the I/O functionality into a new io_mutex. This means taking both mutexes in the DMA path, replacing the existing mutex with the new I/O one in the message pump (the mutex now always being taken in the message pump) and taking the bus lock mutex in spi_sync(), allowing __spi_sync() to have no mutex handling. While we're at it hoist the mutex further up the message pump before we power up the device so that all power up/down of the block is covered by it and there are no races with in-line pumping of messages. Reported-by: Rich Felker <dalias@libc.org> Tested-by: Rich Felker <dalias@libc.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-07-08spi / ACPI: add support for ACPI reconfigure notificationsOctavian Purdila
This patch adds supports for SPI device enumeration and removal via ACPI reconfiguration notifications that are send as a result of an ACPI table load or unload operation. The code is very similar with the device tree reconfiguration code with only small differences in the way we test and set the enumerated state of the device: * the equivalent of device tree's OF_POPULATED flag is the flags.visited field in the ACPI device and the following wrappers are used to manipulate it: acpi_device_enumerated(), acpi_device_set_enumerated() and acpi_device_clear_enumerated() * the device tree code checks of status of the OF_POPULATED flag to avoid trying to create duplicate Linux devices in two places: once when the controller is probed, and once when the reconfigure event is received; in the ACPI code the check is performed only once when the ACPI namespace is searched because this code path is invoked in both of the two mentioned cases The rest of the enumeration handling is similar with device tree: when the Linux device is unregistered the ACPI device is marked as not enumerated; also, when a device remove notification is received we check that the device is in the enumerated state before continuing with the removal of the Linux device. Signed-off-by: Octavian Purdila <octavian.purdila@intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Mark Brown <broonie@kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-08spi: Add DMA support for spi_flash_read()Vignesh R
Few SPI devices provide accelerated read interfaces to read from SPI-NOR flash devices. These hardwares also support DMA to transfer data from flash to memory either via mem-to-mem DMA or dedicated slave DMA channels. Hence, add support for DMA in order to improve throughput and reduce CPU load. Use spi_map_buf() to get sg table for the buffer and pass it to SPI driver. Signed-off-by: Vignesh R <vigneshr@ti.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-05-23Merge remote-tracking branch 'spi/topic/core' into spi-nextMark Brown
2016-05-04spi: Fix simple typo s/impelment/implementMoritz Fischer
This fixes a simple typo in one of the comments. Signed-off-by: Moritz Fischer <moritz.fischer@ettus.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-04-25spi: return error if kmap'd buffers passed to spi_map_buf()Vignesh R
Current spi_map_buf() implementation supports creates sg_table for vmalloc'd and kmalloc'd buffers. Therefore return error if kmap'd buffer (or any other buffer) is passed to spi_map_buf(). Signed-off-by: Vignesh R <vigneshr@ti.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-04-12spi: let SPI masters ignore their children for PMLinus Walleij
Let all SPI masters ignore their children: when it comes to power management: SPI children have no business doing keeping their parents awake: they are completely autonomous devices that just use their parent to talk, and the latter usecase must be power managed by the host itself on a per-message basis. Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-03-18spi: fix possible deadlock between internal bus locks and bus_lock_flagHeiko Stübner
External users may use spi_bus_lock to get exclusive access. This will also grab the bus_lock_mutex and may therefore result in a deadlock if __spi_pump_messages also tries to get the mutex. Therefore adapt spi_pump_messages as well as spi_sync to preset the bus_locked parameter according to the master->bus_lock_flag. Fixes: 49023d2e4ead ("spi: core: Fix deadlock when sending messages") Signed-off-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-03-11Merge remote-tracking branches 'spi/topic/lp8841', 'spi/topic/msg', ↵Mark Brown
'spi/topic/pl022' and 'spi/topic/pxa2xx' into spi-next
2016-03-11Merge remote-tracking branches 'spi/topic/doc', 'spi/topic/dw' and ↵Mark Brown
'spi/topic/flash' into spi-next
2016-03-11Merge remote-tracking branches 'spi/topic/acpi', 'spi/topic/axi-engine', ↵Mark Brown
'spi/topic/bcm2835' and 'spi/topic/bcm2835aux' into spi-next
2016-03-11Merge remote-tracking branch 'spi/topic/dma' into spi-nextMark Brown
2016-03-11spi: Add gfp parameter to kernel-doc to fix build warningJavier Martinez Canillas
The spi_split_transfers_maxsize() gfp parameter is missing in the function kernel-doc so building gives the following warning: .//drivers/spi/spi.c:2359: warning: No description found for parameter 'gfp' Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-03-09spi: respect the maximum segment size of DMA deviceAndy Shevchenko
The device which is actually does DMA may have a limitation of the maximum segment size. Respect this setting when preparing scatter-gather list. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-03-09spi: core: Fix deadlock when sending messagesJon Hunter
The function __spi_pump_messages() is called by spi_pump_messages() and __spi_sync(). The function __spi_sync() has an argument 'bus_locked' that indicates if it is called with the SPI bus mutex held or not. If 'bus_locked' is false then __spi_sync() will acquire the mutex itself. Commit 556351f14e74 ("spi: introduce accelerated read support for spi flash devices") made a change to acquire the SPI bus mutex within __spi_pump_messages(). However, this change did not check to see if the mutex is already held. If __spi_sync() is called with the mutex held (ie. 'bus_locked' is true), then a deadlock occurs when __spi_pump_messages() is called. Fix this deadlock by passing the 'bus_locked' state from __spi_sync() to __spi_pump_messages() and only acquire the mutex if not already held. In the case where __spi_pump_messages() is called from spi_pump_messages() it is assumed that the mutex is not held and so call __spi_pump_messages() with 'bus_locked' set to false. Finally, move the unlocking of the mutex to the end of the __spi_pump_messages() function to simplify the code and only call cond_resched() if there are no errors. Fixes: 556351f14e74 ("spi: introduce accelerated read support for spi flash devices") Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-22spi: make xmldocs warning caused by spi.cMasanari Iida
This patch fix following warnings while make xmldocs. .//drivers/spi/spi.c:2354: warning: Excess function parameter 'message' description in 'spi_split_transfers_maxsize' .//drivers/spi/spi.c:2354: warning: Excess function parameter 'max_size' description in 'spi_split_transfers_maxsize' Signed-off-by: Masanari Iida <standby24x7@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-18spi: Add cond_resched() in main message processing loopMark Brown
When a controller has only PIO support it is very likely that we will run into use cases where we spend a very large amount of time consuming CPU. Code that does this should call cond_resched() every once in a while to give other tasks more of a chance to run so do that in the main SPI loop, the overhead is negligable if it's not needed. Suggested-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-18spi: docbook: add missing parameter documentationMartin Sperl
Add missing docbook documentation for the gfp parameter in function spi_replace_transfers. Signed-off-by: Martin Sperl <kernel@martin.sperl.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-17spi: core: Use min_t(size_t,..)Fabio Estevam
Use min_t(size_t,..) in order to avoid the following build warning on ARM64: include/linux/kernel.h:754:17: warning: comparison of distinct pointer types lacks a cast (void) (&_min1 == &_min2); \ ^ drivers/spi/spi.c:2304:17: note: in expansion of macro 'min' xfers[0].len = min(maxsize, xfer[0].len); Suggested-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com> Acked-by: Martin Sperl <kernel@martin.sperl.org> Signed-off-by: Mark Brown <broonie@kernel.org>