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path: root/drivers/spi/spi.c
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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>
2016-02-17spi: core: Use %zu for printing 'size_t' typeFabio Estevam
Use %zu for printing 'size_t' type in order to fix the following build warning on ARM64: drivers/spi/spi.c: In function '__spi_split_transfer_maxsize': drivers/spi/spi.c:2278:2: warning: format '%i' expects argument of type 'int', but argument 4 has type 'size_t' [-Wformat=] Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Martin Sperl <kernel@martin.sperl.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-15spi: core: Staticize __spi_split_transfer_maxsize()Fabio Estevam
__spi_split_transfer_maxsize() can be made static as it is only used in this file. This fixes the following sparse warning: drivers/spi/spi.c:2266:5: warning: symbol '__spi_split_transfer_maxsize' was not declared. Should it be static? Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-12spi: checking for NULL instead of IS_ERRDan Carpenter
spi_replace_transfers() returns error pointers on error, it never returns NULL. Fixes: d9f121227281 ('spi: core: add spi_split_transfers_maxsize') Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-09spi: introduce accelerated read support for spi flash devicesVignesh R
In addition to providing direct access to SPI bus, some spi controller hardwares (like ti-qspi) provide special port (like memory mapped port) that are optimized to improve SPI flash read performance. This means the controller can automatically send the SPI signals required to read data from the SPI flash device. For this, SPI controller needs to know flash specific information like read command to use, dummy bytes and address width. Introduce spi_flash_read() interface to support accelerated read over SPI flash devices. SPI master drivers can implement this callback to support interfaces such as memory mapped read etc. m25p80 flash driver and other flash drivers can call this make use of such interfaces. The interface should only be used with SPI flashes and cannot be used with other SPI devices. Signed-off-by: Vignesh R <vigneshr@ti.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-09spi: core: add spi_split_transfers_maxsizeMartin Sperl
Add spi_split_transfers_maxsize method that splits spi_transfers transparently into multiple transfers that are below the given max-size. This makes use of the spi_res framework via spi_replace_transfers to allocate/free the extra transfers as well as reverting back the changes applied while processing the spi_message. Signed-off-by: Martin Sperl <kernel@martin.sperl.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-09spi: core: add spi_replace_transfers methodMartin Sperl
Add the spi_replace_transfers method that can get used to replace some spi_transfers from a spi_message with other transfers. Signed-off-by: Martin Sperl <kernel@martin.sperl.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-09spi: core: added spi_resource managementMartin Sperl
SPI resource management framework used while processing a spi_message via the spi-core. The basic idea is taken from devres, but as the allocation may happen fairly frequently, some provisioning (in the form of an unused spi_device pointer argument to spi_res_alloc) has been made so that at a later stage we may implement reuse objects allocated earlier avoiding the repeated allocation by keeping a cache of objects that we can reuse. This framework can get used for: * rewriting spi_messages * to fullfill alignment requirements of the spi_master HW * to fullfill transfer length requirements (e.g: transfers need to be less than 64k) * consolidate spi_messages with multiple transfers into a single transfer when the total transfer length is below a threshold. * reimplement spi_unmap_buf without explicitly needing to check if it has been mapped Signed-off-by: Martin Sperl <kernel@martin.sperl.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-02-09spi: Let drivers translate ACPI DeviceSelection to suitable Linux chip selectMika Westerberg
In Windows it is up to the SPI host controller driver to handle the ACPI DeviceSelection as it likes. The SPI core does not take any part in it. This is different in Linux because we always expect to have chip select in range of 0 .. master->num_chipselect - 1. In order to support this in Linux we need a way to allow the driver to translate between ACPI DeviceSelection field and Linux chip select number so provide a new optional hook ->fw_translate_cs() that can be used by a driver to handle translation and call this hook if set during SPI slave ACPI enumeration. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-01-13Merge tag 'spi-v4.5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi Pull spi updates from Mark Brown: "A quiet release for SPI, not even many driver updates: - Add a dummy loopback driver for use in exercising framework features during development. - Move the test utilities to tools/ and add support for transferring data to and from a file instead of stdin and stdout to spidev_test. - Support for Mediatek MT2701 and Renesas AG5 deices" * tag 'spi-v4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (69 commits) spi: loopback: fix typo in MODULE_PARM_DESC spi: sun4i: Prevent chip-select from being activated twice before a transfer spi: loopback-test: spi_check_rx_ranges can get always done spi: loopback-test: rename method spi_test_fill_tx to spi_test_fill_pattern spi: loopback-test: write rx pattern also when running without tx_buf spi: fsl-espi: expose maximum transfer size limit spi: expose master transfer size limitation. spi: zynq: use to_platform_device() spi: cadence: use to_platform_device() spi: mediatek: Add spi support for mt2701 IC spi: mediatek: merge all identical compat to mtk_common_compat spi: mtk: Add bindings for mediatek MT2701 soc platform spi: mediatek: Prevent overflows in FIFO transfers spi: s3c64xx: Remove unused platform_device_id entries spi: use to_spi_device spi: dw: Use SPI_TMOD_TR rather than magic const 0 to set tmode spi: imx: defer spi initialization, if DMA engine is spi: imx: return error from dma channel request spi: imx: enable loopback only for ECSPI controller family spi: imx: fix loopback mode setup after controller reset ...
2016-01-11Merge remote-tracking branches 'spi/topic/overlay', 'spi/topic/pxa2xx', ↵Mark Brown
'spi/topic/s3c64xx', 'spi/topic/sh-msiof' and 'spi/topic/spidev' into spi-next
2016-01-11Merge remote-tracking branch 'spi/topic/core' into spi-nextMark Brown
2016-01-01ACPI / spi: attach GPIO IRQ from ACPI description to SPI deviceChristophe RICARD
spi->irq was ignoring GpioInt property setting it to -1. acpi_dev_gpio_irq_get returns and configure the slave IRQ according to the ACPI slave node description. It is now inline with devicetree behavior. Acked-by: Mark Brown <broonie@kernel.org> Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-23spi: use to_spi_deviceGeliang Tang
Use to_spi_device() instead of open-coding it. Signed-off-by: Geliang Tang <geliangtang@163.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-12-16Merge remote-tracking branch 'spi/fix/core' into spi-linusMark Brown
2015-12-16spi: fix parent-device reference leakJohan Hovold
Fix parent-device reference leak due to SPI-core taking an unnecessary reference to the parent when allocating the master structure, a reference that was never released. Note that driver core takes its own reference to the parent when the master device is registered. Fixes: 49dce689ad4e ("spi doesn't need class_device") Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Mark Brown <broonie@kernel.org> Cc: stable@vger.kernel.org
2015-12-01spi: Mark instantiated device nodes with OF_POPULATEGeert Uytterhoeven
Mark (and unmark) device nodes with the POPULATE flag as appropriate. This is required to avoid multi probing when enabling and populating SPI buses in DT overlays. Based on commit 4f001fd30145a6a8 ("i2c: Mark instantiated device nodes with OF_POPULATE"). Suggested-by: Mark Brown <broonie@kernel.org> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-12-01spi: Uninline spi_unregister_device()Geert Uytterhoeven
Uninline spi_unregister_device() in preparation of adding more code to it. Add kerneldoc documentation while we're at it. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-11-30Merge remote-tracking branches 'spi/fix/bcm63xx', 'spi/fix/doc', ↵Mark Brown
'spi/fix/mediatek' and 'spi/fix/pl022' into spi-linus
2015-11-27spi: bugfix: spi_message.transfer_length does not get resetMartin Sperl
When submitting an identical spi_message multiple times via spi_sync the spi_message.frame_length does not get reset to 0 in __spi_validate before adding up all spi_transfer.len resulting in frame_length > actual_length on all but the first spi_sync call. Signed-off-by: Martin Sperl <kernel@martin.sperl.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-11-10spi: Add missing kerneldoc description for parameterThierry Reding
Commit ca5d24854210 ("spi: Add THIS_MODULE to spi_driver in SPI core") adds the new __spi_register_driver() function, but keeps the kerneldoc for the spi_register_driver() function in place and forgets to add the description for the new owner parameter. Signed-off-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-11-04Merge remote-tracking branches 'spi/topic/omap-100k', ↵Mark Brown
'spi/topic/omap-uwire', 'spi/topic/owner', 'spi/topic/pxa' and 'spi/topic/pxa2xx' into spi-next
2015-11-04Merge remote-tracking branch 'spi/topic/doc' into spi-nextMark Brown
2015-11-04Merge remote-tracking branch 'spi/topic/core' into spi-nextMark Brown
2015-11-04Merge remote-tracking branch 'spi/fix/core' into spi-linusMark Brown
2015-10-28spi: Add THIS_MODULE to spi_driver in SPI coreAndrew F. Davis
Add spi_register_driver helper macro that adds THIS_MODULE to spi_driver for the registering driver. We rename and modify the existing spi_register_driver to enable this. Signed-off-by: Andrew F. Davis <afd@ti.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-28spi: Setup the master controller driver before setting the chipselectFranklin S Cooper Jr
SPI controllers may need to be properly setup before chip selects can be used. Therefore, wait until the spi controller has a chance to perform their setup procedure before trying to use the chip select. This also insures that the chip selects pins are in a good state before asseting them which otherwise may cause confusion. Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com> Tested-by: Grygorii Strashko <grygorii.strashko@ti.com> Tested-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-24spi: fix kernel-doc warnings about missing return desc in spi.cJavier Martinez Canillas
When building docs with make htmldocs, warnings about not having a description for the return value are reported, i.e: warning: No description found for return value of 'spi_register_driver' Fix these by following the kernel-doc conventions explained in Documentation/kernel-doc-nano-HOWTO.txt. Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-24Merge branches 'topic/core' and 'topic/stats' of ↵Mark Brown
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-doc
2015-10-21spi: core: use gpio_is_valid() helperAndy Shevchenko
Check if GPIO pin is valid by API helper function. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-16spi: core: propagate return code of __spi_validate_bits_per_word()Andy Shevchenko
Propagate the actual return code of __spi_validate_bits_per_word() in spi_setup(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-12spi: Map SPI OF client IRQ at probe timeJon Hunter
Currently the IRQs for SPI client devices, registered via device-tree, are mapped when the client devices are registered. If the corresponding irq-chip has not been probed yet, then the probing of the client device will fail and will not be retried. Resolve this by mapping the IRQ at probe time and allow the probe to be deferred if the IRQ is not yet available. If of_irq_get() returns an error that is not -EPROBE_DEFER, then assume that the SPI client does not have an IRQ and set the IRQ number to zero (which is equivalent to irq_of_parse_and_map()). This is based on some inputs from Thierry Reding <treding@nvidia.com>. Cc: Thierry Reding <treding@nvidia.com> Cc: Tomeu Vizoso <tomeu.vizoso@collabora.com> Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-09-19spi: add transfer histogram statistics via sysfsMartin Sperl
report transfer sizes as a histogram via the following files: /sys/class/spi_master/spi*/statistics/transfer_bytes_histo_* /sys/class/spi_master/spi*/spi*.*/statistics/transfer_bytes_histo_* Signed-off-by: Martin Sperl <kernel@martin.sperl.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-09-16Merge tag 'v4.3-rc1' into spi-fix-docMark Brown
Linux 4.3-rc1
2015-09-06spi: Fix documentation of spi_alloc_master()Guenter Roeck
Actually, spi_master_put() after spi_alloc_master() must _not_ be followed by kfree(). The memory is already freed with the call to spi_master_put() through spi_master_class, which registers a release function. Calling both spi_master_put() and kfree() results in often nasty (and delayed) crashes elsewhere in the kernel, often in the networking stack. This reverts commit eb4af0f5349235df2e4a5057a72fc8962d00308a. Link to patch and concerns: https://lkml.org/lkml/2012/9/3/269 or http://lkml.iu.edu/hypermail/linux/kernel/1209.0/00790.html Alexey Klimov: This revert becomes valid after 94c69f765f1b4a658d96905ec59928e3e3e07e6a when spi-imx.c has been fixed and there is no need to call kfree() so comment for spi_alloc_master() should be fixed. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Alexey Klimov <alexey.klimov@linaro.org> Signed-off-by: Mark Brown <broonie@kernel.org> Cc: stable@vger.kernel.org
2015-08-31Merge remote-tracking branches 'spi/topic/s3c64xx', 'spi/topic/sg', ↵Mark Brown
'spi/topic/sh-msiof', 'spi/topic/spidev' and 'spi/topic/stats' into spi-next
2015-08-31Merge remote-tracking branch 'spi/topic/dma' into spi-nextMark Brown
2015-08-26spi: check bits_per_word in spi_setupStefan Brüns
This allows drivers for devices connected via SPI to check if the controller supports a given bits_per_word value during setup. Currently any BPW value is accepted durings setup, and transfers are rejected later. Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-08-21spi: Fall back to master maximum speed if no slave speed specifiedMark Brown
If a slave appears with no maximum transfer speed specified fall back to using the maximum for the master instead. It's questionable if we should let slaves do this but let's be defensive. Signed-off-by: Mark Brown <broonie@kernel.org>
2015-07-24spi: support spi without dma channel to use can_dma()Leilk Liu
For spi without dma channel and use can_dma(), it can use master->dev for struct device. Signed-off-by: Leilk Liu <leilk.liu@mediatek.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-07-07spi: expose spi_master and spi_device statistics via sysfsMartin Sperl
per spi-master statistics accessible as: /sys/class/spi_master/spi*/statistics/* per spi-device statistics accessible via: /sys/class/spi_master/spi*/spi*.*/statistics/* The following statistics are exposed as separate "files" inside these directories: * messages number of spi_messages * transfers number of spi_transfers * bytes number of bytes transferred * bytes_rx number of bytes transmitted * bytes_tx number of bytes received * errors number of errors encounterd * timedout number of messages that have timed out * spi_async number of spi_messages submitted using spi_async * spi_sync number of spi_messages submitted using spi_sync * spi_sync_immediate number of spi_messages submitted using spi_sync, that are handled immediately without a context switch to the spi_pump worker-thread Signed-off-by: Martin Sperl <kernel@martin.sperl.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-07-07spi: Fix per-page mapping of unaligned vmalloc-ed bufferAndrew Gabbasov
spi_map_buf() processes mapping of vmalloc-ed buffers in a special way, making mapping of every page separately. However, if the buffer is not aligned to page boundary (e.g. sub-array in a vmalloc-ed array), it fills the scatter table with page-size unaligned pieces, that cross page boundaries. This is incorrect and can, for example, cause memory corruption and various crashes when working with ubifs on spi-nor chips (though those drivers are themselves buggy in that they should be providing DMAable memory to the SPI framework). Fix this by using proper scatter table size and intra-page buffer lengths, so that the whole buffer splits into separate scatter table entries on page boundaries. Signed-off-by: Andrew Gabbasov <andrew_gabbasov@mentor.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-06-02spi: restore rx/tx_buf in case of unset CONFIG_HAS_DMAMartin Sperl
The case where spi_master sets the flags SPI_MASTER_MUST_RX/TX while CONFIG_HAS_DMA is unset (which is unlikley) together with a driver that reuses spi_messages with rx/tx_buff set to NULL, can result in: * data disclosure over the SPI (for tx_buf == NULL) * memory corruption (for rx_buf == NULL) This happenes when dummy_rx/dummy_tx are changing address due to krealloc or free and an allocation of the memory by a different part of the kernel. Signed-off-by: Martin Sperl <kernel@martin.sperl.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-05-11spi: fix race freeing dummy_tx/rx before it is unmappedMartin Sperl
Fix a race (with some kernel configurations) where a queued master->pump_messages runs and frees dummy_tx/rx before spi_unmap_msg is running (or is finished). This results in the following messages: BUG: Bad page state in process page:db7ba030 count:0 mapcount:0 mapping: (null) index:0x0 flags: 0x200(arch_1) page dumped because: PAGE_FLAGS_CHECK_AT_PREP flag set ... Reported-by: Noralf Trønnes <noralf@tronnes.org> Suggested-by: Noralf Trønnes <noralf@tronnes.org> Tested-by: Noralf Trønnes <noralf@tronnes.org> Signed-off-by: Martin Sperl <kernel@martin.sperl.org> Signed-off-by: Mark Brown <broonie@kernel.org> Cc: stable@vger.kernel.org
2015-04-16spi: check tx_buf and rx_buf in spi_unmap_msgRobin Gong
Some spi device drivers use the same tx_buf and rx_buf repeatly for better performance such as driver/input/touchsreen/ads7846.c, but spi core grab tx_buf /rx_buf of transfer and set them as dummy_tx/dummy_rx once they are NULL. Thus, in the second time the tx_buf/rx_buf will be replaced by dummy_tx/dummy_rx and the data which produced by the last tx or rx may be wrongly sent to the device or handled by the upper level protocol. This patch just keep the orignal value of tx_buf/rx_buf if they are NULL after this transfer processed. Signed-off-by: Robin Gong <b38343@freescale.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-04-11Merge remote-tracking branches 'spi/topic/omap-100k', ↵Mark Brown
'spi/topic/omap-uwire', 'spi/topic/pl022', 'spi/topic/pm' and 'spi/topic/pxa2xx' into spi-next