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path: root/drivers/spi/spi.c
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2017-11-10Merge remote-tracking branch 'spi/topic/core' into spi-nextMark Brown1-1/+3
2017-11-03spi: fix IDR collision on systems with both fixed and dynamic SPI bus numbersLucas Stach1-4/+9
On systems where some controllers get a dynamic ID assigned and some have a fixed number from DT, the current implemention might run into an IDR collision if the dynamic controllers gets probed first and get an IDR number, which is later requested by the controller with the fixed numbering. When this happens the fixed controller will fail to register with the SPI core. Fix this by skipping all known alias numbers when assigning the dynamic IDs. Fixes: 9b61e302210e (spi: Pick spi bus number from Linux idr or spi alias) Signed-off-by: Lucas Stach <l.stach@pengutronix.de> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-10-31spi: document odd controller reference handlingJohan Hovold1-1/+3
Document the fact that a reference to the controller is dropped as part of deregistration. This is an odd pattern as the reference is typically taken in __spi_alloc_controller() rather than spi_register_controller(). Most controller drivers gets it right these days and notably the device-managed interface relies on this behaviour. Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-10-31spi: fix use-after-free at controller deregistrationJohan Hovold1-2/+3
The controller is typically freed as part of device_unregister() so store the bus id before deregistration to avoid use-after-free when the id is later released. Fixes: 9b61e302210e ("spi: Pick spi bus number from Linux idr or spi alias") Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Mark Brown <broonie@kernel.org> Cc: stable <stable@vger.kernel.org>
2017-09-05Merge tag 'acpi-4.14-rc1' of ↵Linus Torvalds1-0/+32
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI updates from Rafael Wysocki: "These include a usual ACPICA code update (this time to upstream revision 20170728), a fix for a boot crash on some systems with Thunderbolt devices connected at boot time, a rework of the handling of PCI bridges when setting up device wakeup, new support for Apple device properties, support for DMA configurations reported via ACPI on ARM64, APEI-related updates, ACPI EC driver updates and assorted minor modifications in several places. Specifics: - Update the ACPICA code in the kernel to upstream revision 20170728 including: * Alias operator handling update (Bob Moore). * Deferred resolution of reference package elements (Bob Moore). * Support for the _DMA method in walk resources (Bob Moore). * Tables handling update and support for deferred table verification (Lv Zheng). * Update of SMMU models for IORT (Robin Murphy). * Compiler and disassembler updates (Alex James, Erik Schmauss, Ganapatrao Kulkarni, James Morse). * Tools updates (Erik Schmauss, Lv Zheng). * Assorted minor fixes and cleanups (Bob Moore, Kees Cook, Lv Zheng, Shao Ming). - Rework the initialization of non-wakeup GPEs with method handlers in order to address a boot crash on some systems with Thunderbolt devices connected at boot time where we miss an early hotplug event due to a delay in GPE enabling (Rafael Wysocki). - Rework the handling of PCI bridges when setting up ACPI-based device wakeup in order to avoid disabling wakeup for bridges prematurely (Rafael Wysocki). - Consolidate Apple DMI checks throughout the tree, add support for Apple device properties to the device properties framework and use these properties for the handling of I2C and SPI devices on Apple systems (Lukas Wunner). - Add support for _DMA to the ACPI-based device properties lookup code and make it possible to use the information from there to configure DMA regions on ARM64 systems (Lorenzo Pieralisi). - Fix several issues in the APEI code, add support for exporting the BERT error region over sysfs and update APEI MAINTAINERS entry with reviewers information (Borislav Petkov, Dongjiu Geng, Loc Ho, Punit Agrawal, Tony Luck, Yazen Ghannam). - Fix a potential initialization ordering issue in the ACPI EC driver and clean it up somewhat (Lv Zheng). - Update the ACPI SPCR driver to extend the existing XGENE 8250 workaround in it to a new platform (m400) and to work around an Xgene UART clock issue (Graeme Gregory). - Add a new utility function to the ACPI core to support using ACPI OEM ID / OEM Table ID / Revision for system identification in blacklisting or similar and switch over the existing code already using this information to this new interface (Toshi Kani). - Fix an xpower PMIC issue related to GPADC reads that always return 0 without extra pin manipulations (Hans de Goede). - Add statements to print debug messages in a couple of places in the ACPI core for easier diagnostics (Rafael Wysocki). - Clean up the ACPI processor driver slightly (Colin Ian King, Hanjun Guo). - Clean up the ACPI x86 boot code somewhat (Andy Shevchenko). - Add a quirk for Dell OptiPlex 9020M to the ACPI backlight driver (Alex Hung). - Assorted fixes, cleanups and updates related to ACPI (Amitoj Kaur Chawla, Bhumika Goyal, Frank Rowand, Jean Delvare, Punit Agrawal, Ronald Tschalär, Sumeet Pawnikar)" * tag 'acpi-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (75 commits) ACPI / APEI: Suppress message if HEST not present intel_pstate: convert to use acpi_match_platform_list() ACPI / blacklist: add acpi_match_platform_list() ACPI, APEI, EINJ: Subtract any matching Register Region from Trigger resources ACPI: make device_attribute const ACPI / sysfs: Extend ACPI sysfs to provide access to boot error region ACPI: APEI: fix the wrong iteration of generic error status block ACPI / processor: make function acpi_processor_check_duplicates() static ACPI / EC: Clean up EC GPE mask flag ACPI: EC: Fix possible issues related to EC initialization order ACPI / PM: Add debug statements to acpi_pm_notify_handler() ACPI: Add debug statements to acpi_global_event_handler() ACPI / scan: Enable GPEs before scanning the namespace ACPICA: Make it possible to enable runtime GPEs earlier ACPICA: Dispatch active GPEs at init time ACPI: SPCR: work around clock issue on xgene UART ACPI: SPCR: extend XGENE 8250 workaround to m400 ACPI / LPSS: Don't abort ACPI scan on missing mem resource mailbox: pcc: Drop uninformative output during boot ACPI/IORT: Add IORT named component memory address limits ...
2017-09-04Merge remote-tracking branches 'spi/topic/cadence', 'spi/topic/dt', ↵Mark Brown1-16/+11
'spi/topic/ep93xx' and 'spi/topic/falcon' into spi-next
2017-08-17spi: Kernel coding style fixesSuniel Mahesh1-17/+12
Earlier commit: "spi: Pick spi bus number from Linux idr or spi alias" (SHA1:9b61e302210eba55768962f2f11e96bb508c2408) has introduced some checkpatch issues. As pointed by Lukas Wunner this patch does the following: - remove whitespaces - fix warnings, suspect code indent for conditional statements - fix errors, code indent should use tabs - remove spaces at the start of the line Signed-off-by: Suniel Mahesh <sunil.m@techveda.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-08-16spi: Pick spi bus number from Linux idr or spi aliasSuniel Mahesh1-15/+56
Modify existing code, for automatically picking the spi bus number based on Linux idr scheme as mentioned in FIXME. This patch does the following: (a) Remove the now unnecessary code which was allocating bus numbers using ATOMIC_INIT and atomic_dec_return macros. (b) If we have an alias, pick the bus number from alias ID (c) Convert to linux idr interface Signed-off-by: Suniel Mahesh <sunil.m@techveda.org> Signed-off-by: Karthik Tummala <karthik@techveda.org> Tested-by: Karthik Tummala <karthik@techveda.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-08-07spi: use of_property_read_bool()Sergei Shtylyov1-5/+5
Use a bit more compact of_property_read_bool() calls instead of the of_find_property() calls -- symmetrically with the of_property_read_u32() calls already done in of_spi_parse_dt(). Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-08-03spi: Use Apple device properties in absence of ACPI resourcesLukas Wunner1-0/+32
MacBooks and MacBook Pros introduced since 2015 return empty _CRS data for SPI slaves, causing device initialization to fail. Most of the information that would normally be conveyed via _CRS is available through ACPI device properties instead, so take advantage of them. The meaning and appropriate usage of the device properties was reverse engineered by Ronald Tschalär and carried over from these commits authored by him: https://github.com/cb22/macbook12-spi-driver/commit/9a416d699ef4 https://github.com/cb22/macbook12-spi-driver/commit/0c34936ed9a1 According to Ronald, the device properties have the following meaning: spiSclkPeriod /* period in ns */ spiWordSize /* in number of bits */ spiBitOrder /* 1 = MSB_FIRST, 0 = LSB_FIRST */ spiSPO /* clock polarity: 0 = low, 1 = high */ spiSPH /* clock phase: 0 = first, 1 = second */ spiCSDelay /* delay between cs and receive on reads in 10 us */ resetA2RUsec /* active-to-receive delay? */ resetRecUsec /* receive delay? */ Reported-by: Leif Liddy <leif.liddy@gmail.com> Tested-by: Ronald Tschalär <ronald@innovation.ch> Acked-by: Mark Brown <broonie@kernel.org> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-07-26spi: core: Propagate error code of add_uevent_var()Andy Shevchenko1-2/+1
add_uevent_var() can fail, let caller know about this. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-07-19spi: Convert to using %pOF instead of full_nameRob Herring1-16/+11
Now that we have a custom printf format specifier, convert users of full_name to use %pOF instead. This is preparation to remove storing of the full path string for each node. Signed-off-by: Rob Herring <robh@kernel.org> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-06-13spi: Generalize SPI "master" to "controller"Geert Uytterhoeven1-539/+542
Now struct spi_master is used for both SPI master and slave controllers, it makes sense to rename it to struct spi_controller, and replace "master" by "controller" where appropriate. For now this conversion is done for SPI core infrastructure only. Wrappers are provided for backwards compatibility, until all SPI drivers have been converted. Noteworthy details: - SPI_MASTER_GPIO_SS is retained, as it only makes sense for SPI master controllers, - spi_busnum_to_master() is retained, as it looks up masters only, - A new field spi_device.controller is added, but spi_device.master is retained for compatibility (both are always initialized by spi_alloc_device()), - spi_flash_read() is used by SPI masters only. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-06-13Merge branches 'topic/core', 'topic/slave' and 'fix/doc' of ↵Mark Brown1-25/+156
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-master
2017-05-26spi: core: Add support for registering SPI slave controllersGeert Uytterhoeven1-24/+155
Add support for registering SPI slave controllers using the existing SPI master framework: - SPI slave controllers must use spi_alloc_slave() instead of spi_alloc_master(), and should provide an additional callback "slave_abort" to abort an ongoing SPI transfer request, - SPI slave controllers are added to a new "spi_slave" device class, - SPI slave handlers can be bound to the SPI slave device represented by an SPI slave controller using a DT child node named "slave", - Alternatively, (un)binding an SPI slave handler to the SPI slave device represented by an SPI slave controller can be done by (un)registering the slave device through a sysfs virtual file named "slave". From the point of view of an SPI slave protocol handler, an SPI slave controller looks almost like an ordinary SPI master controller. The only exception is that a transfer request will block on the remote SPI master, and may be cancelled using spi_slave_abort(). Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-05-14spi: core: Replace S_IRUGO permissions by 0444Geert Uytterhoeven1-2/+2
Octal permissions are preferred over symbolic permissions. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-05-14spi: core: Fix devm_spi_register_master() function name in kerneldocGeert Uytterhoeven1-1/+1
Fixes: 666d5b4c742ba666 ("spi: core: Add devm_spi_register_master()") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-04-26Merge remote-tracking branches 'spi/topic/ti-qspi' and 'spi/topic/xlp' into ↵Mark Brown1-1/+1
spi-next
2017-04-26Merge remote-tracking branches 'spi/topic/devprop', 'spi/topic/fsl', ↵Mark Brown1-5/+29
'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 Brown1-1/+1
2017-04-21spi: Add can_dma like interface for spi_flash_readVignesh R1-1/+1
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 Mehrtens1-1/+1
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 Torokhov1-1/+1
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 Torokhov1-4/+28
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 Molnar1-0/+1
<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 Torvalds1-1/+3
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 Brown1-24/+36
'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 Brown1-4/+4
2017-02-07spi: acpi: Initialize modalias from of_compatibleDan O'Donovan1-1/+3
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 Hovold1-2/+6
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 Kurtz1-4/+4
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 Elfring1-1/+1
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 Uytterhoeven1-24/+36
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 Brown1-2/+8
'spi/topic/fsl-dspi' and 'spi/topic/fsl-espi' into spi-next
2016-12-12Merge remote-tracking branch 'spi/topic/dma' into spi-nextMark Brown1-2/+5
2016-12-12Merge remote-tracking branch 'spi/topic/core' into spi-nextMark Brown1-2/+7
2016-11-22spi: use sg_next for walking through the allocated scatterlist tableJuan Gutierrez1-2/+5
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 Kurtz1-2/+8
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 Ramsauer1-1/+4
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 Thayer1-2/+7
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 Mladek1-9/+9
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 Thayer1-2/+7
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 Brown1-3/+14
2016-09-06Merge remote-tracking branches 'spi/fix/lock', 'spi/fix/maintainers', ↵Mark Brown1-2/+8
'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 Wu1-2/+6
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 R1-3/+14
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 Brown1-0/+2
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 Torvalds1-20/+46
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 Brown1-20/+18
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 Purdila1-7/+93
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>
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-23 04:47:06 +0000