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path: root/include/linux/spi/spi_bitbang.h
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2019-04-08spi: bitbang: Introduce spi_bitbang_init()Andrey Smirnov
Move all of the code doing struct spi_bitbang initialization, so that it can be paired with devm_spi_register_master() in order to avoid having to call spi_bitbang_stop() explicitly. Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com> Cc: Mark Brown <broonie@kernel.org> Cc: Chris Healy <cphealy@gmail.com> Cc: linux-spi@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Mark Brown <broonie@kernel.org>
2018-08-01spi: spi-gpio: add SPI_3WIRE supportLorenzo Bianconi
Add SPI_3WIRE support to spi-gpio controller introducing set_line_direction function pointer in spi_bitbang data structure. Spi-gpio controller has been tested using hts221 temp/rh iio sensor running in 3wire mode and lsm6dsm running in 4wire mode Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2018-08-01spi: add flags parameter to txrx_word function pointersLorenzo Bianconi
Add the capability to specify the flag parameter used in bitbang_txrx_be_cpha{0,1} through the txrx_word function pointers of spi_bitbang data structure. That feature will be used to add spi-3wire support to the spi-gpio controller Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2018-07-18spi: spi-bitbang: change flags from u8 to u16David Lechner
This changes the data type of the flags field in struct spi_bitbang from u8 to u16. This matches the size of the mode field of struct spi_device where these flags are also used. This is done in preparation of adding a new SPI mode flag that will be used with this field that would otherwise not fit in 8 bits. Signed-off-by: David Lechner <david@lechnology.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-09-17spi: bitbang: Replace spinlock by mutexNicolas Boichat
chipselect (in the case of spi-gpio: spi_gpio_chipselect, which calls gpiod_set_raw_value_cansleep) can sleep, so we should not hold a spinlock while calling it from spi_bitbang_setup. This issue was introduced by this commit, which converted spi-gpio to cansleep variants: d9dda5a191 "spi: spi-gpio: Use 'cansleep' variants to access GPIO" Replacing the lock variable by a mutex fixes the issue: This is safe as all instances where the lock is used are called from contexts that can sleep. Finally, update spi-ppc4xx and and spi-s3c24xx to use mutex functions, as they directly hold the lock for similar purpose. Signed-off-by: Nicolas Boichat <drinkcat@chromium.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2014-03-29spi: bitbang: Make spi_bitbang_stop() return voidAxel Lin
spi_bitbang_stop() never fails, so make it return void. Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-07-17spi/bitbang: Use core message pumpMark Brown
Convert drivers using bitbang to use the core mesasge pump infrastructure, saving some code and meaning that these drivers get to take advantage of work done on improving the core implementation. Signed-off-by: Mark Brown <broonie@linaro.org>
2013-07-15spi/bitbang: Unexport spi_bitbang_transfer()Mark Brown
Currently no drivers use the ability to override spi_bitbang_transfer() and if any started this would make it harder to convert the bitbang code to use transfer_one_message() so remove the export in order to prevent anyone starting. Signed-off-by: Mark Brown <broonie@linaro.org>
2010-05-25spi: move bitbang txrx utility functions to private headerhartleys
A number of files in drivers/spi fail checkincludes.pl due to the double include of <linux/spi/spi_bitbang.h>. The first include is needed to get the struct spi_bitbang definition and the spi_bitbang_* function prototypes. The second include happens after defining EXPAND_BITBANG_TXRX to get the inlined bitbang_txrx_* utility functions. The <linux/spi/spi_bitbang.h> header is also included by a number of other spi drivers, as well as some arch/ code, in order to use struct spi_bitbang and the associated functions. To fix the double include, and remove any potential confusion about it, move the inlined bitbang_txrx_* functions to a new private header in drivers/spi and also remove the need to define EXPAND_BITBANG_TXRX. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2009-11-09tree-wide: fix typos "selct" + "slect" -> "select"Uwe Kleine-König
This patch was generated by git grep -E -i -l 's(le|el)ct' | xargs -r perl -p -i -e 's/([Ss])(le|el)ct/$1elect/ with only skipping net/netfilter/xt_SECMARK.c and include/linux/netfilter/xt_SECMARK.h which have a struct member called selctx. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-02-20spi_bitbang: add more lowlevel function documentationMichael Buesch
This adds more documentation of the lowlevel API to avoid future bugs. Signed-off-by: Michael Buesch <mb@bu3sch.de> Acked-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-30spi: fix compile errorFernando Luis Vazquez Cao
Fix compile error below: LD drivers/spi/built-in.o CC [M] drivers/spi/spi_gpio.o In file included from drivers/spi/spi_gpio.c:26: include/linux/spi/spi_bitbang.h:23: error: field `work' has incomplete type make[2]: *** [drivers/spi/spi_gpio.o] Error 1 make[1]: *** [drivers/spi] Error 2 make: *** [drivers] Error 2 Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-17SPI controller drivers: check for unsupported modesDavid Brownell
Minor SPI controller driver updates: make the setup() methods reject spi->mode bits they don't support, by masking aginst the inverse of bits they *do* support. This insures against misbehavior later when new mode bits get added. Most controllers can't support SPI_LSB_FIRST; more handle SPI_CS_HIGH. Support for all four SPI clock/transfer modes is routine. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-16[PATCH] spi: destroy workqueue after spi_unregister_masterChris Lesiak
Fix a bug in the cleanup of an spi_bitbang bus. The workqueue associated with the bus was destroyed before the call to spi_unregister_master. That meant that spi devices on that bus would be unable to do IO in their remove method. The shutdown flag should have been able to prevent a segfault, but was never getting set. By waiting to destroy the workqueue until after the master is unregistered, devices are able to do IO in their remove methods. An added benefit is that neither the shutdown flag nor a wait for the queue of messages to empty is needed. Signed-off-by: Chris Lesiak <chris.lesiak@licor.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12[PATCH] SPI cleanup() method param becomes non-constHans-Peter Nilsson
I'd like to assign NULL to kfree()d members of a structure. I can't do that without ugly casting (see the PXA patch) when the structure pointed to is const-qualified. I don't really see a reason why the cleanup method isn't allowed to alter the object it should clean up. :-) No, I didn't test the PXA patch, but I verified that the NULL-assignment doesn't stop me from doing rmmod/insmodding my own spi_bitbang-based driver. Signed-off-by: Hans-Peter Nilsson <hp@axis.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-05-16[PATCH] SPI: Renamed bitbang_transfer_setup to spi_bitbang_setup_transfer ↵Kumar Gala
and export it Renamed bitbang_transfer_setup to follow convention of other exported symbols from spi-bitbang. Exported spi_bitbang_setup_transfer to allow users of spi-bitbang to use the function in their own setup_transfer. Signed-off-by: Kumar Gala <galak@kernel.crashing.org> Cc: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-05-16[PATCH] SPI: per-transfer overrides for wordsize and clockingImre Deak
Some protocols (like one for some bitmap displays) require different clock speed or word size settings for each transfer in an SPI message. This adds those parameters to struct spi_transfer. They are to be used when they are nonzero; otherwise the defaults from spi_device are to be used. The patch also adds a setup_transfer callback to spi_bitbang, uses it for messages that use those overrides, and implements it so that the pure bitbanging code can help resolve any questions about how it should work. Signed-off-by: Imre Deak <imre.deak@nokia.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-13[PATCH] spi: use linked lists rather than an arrayVitaly Wool
This makes the SPI core and its users access transfers in the SPI message structure as linked list not as an array, as discussed on LKML. From: David Brownell <dbrownell@users.sourceforge.net> Updates including doc, bugfixes to the list code, add spi_message_add_tail(). Plus, initialize things _before_ grabbing the locks in some cases (in case it grows more expensive). This also merges some bitbang updates of mine that didn't yet make it into the mm tree. Signed-off-by: Vitaly Wool <vwool@ru.mvista.com> Signed-off-by: Dmitry Pervushin <dpervushin@gmail.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-13[PATCH] spi: add spi_bitbang driverDavid Brownell
This adds a bitbanging spi master, hooking up to board/adapter-specific glue code which knows how to set and read the signals (gpios etc). This code kicks in after the glue code creates a platform_device with the right platform_data. That data includes I/O loops, which will usually come from expanding an inline function (provided in the header). One goal is that the I/O loops should be easily optimized down to a few GPIO register accesses, in common cases, for speed and minimized overhead. This understands all the currently defined protocol tweaking options in the SPI framework, and might eventually serve as as reference implementation. - different word sizes (1..32 bits) - differing clock rates - SPI modes differing by CPOL (affecting chip select and I/O loops) - SPI modes differing by CPHA (affecting I/O loops) - delays (usecs) after transfers - temporarily deselecting chips in mid-transfer A lot of hardware could work with this framework, though common types of controller can't reach peak performance without switching to a driver structure that supports pipelining of transfers (e.g. DMA queues) and maybe controllers (e.g. IRQ driven). Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>