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path: root/drivers/spi/spi-bitbang.c
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2015-10-05spi: bitbang: switch to the generic implementation of transfer_one_messageHeiner Kallweit
Change the bitbang driver to use the generic implementation of transfer_one_message. This simplifies the bitbang driver code and provides benefits like the statistics in the generic implementation. Successfully tested on a IMX6-based system (spi-imx) and on a MIPS-based router (OpenWRT with spi-ath79). Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2015-10-05spi: bitbang: remove unneeded checkHeiner Kallweit
Remove an unneeded check. The SPI core (__spi_validate) takes care that these fields are always populated. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.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>
2015-04-18spi: bitbang: Make setup_transfer() callback optionalPelle Nilsson
Some controller drivers have no need of this callback (spi-altera even causes a NULL pointer dereference because it doesn't register the callback, falsely assuming that it is already optional). Fixes: 30af9b558a56 ("spi/bitbang: Drop empty setup() functions") Signed-off-by: Pelle Nilsson <per.nilsson@xelmo.com> Reviewed-by: Ezequiel Garcia <ezequiel.garcia@vanguardiasur.com.ar> Signed-off-by: Mark Brown <broonie@kernel.org>
2014-12-22spi: Remove FSF mailing addressesJarkko Nikula
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2014-03-30Merge remote-tracking branches 'spi/topic/imx', 'spi/topic/init', ↵Mark Brown
'spi/topic/mpc512x-psc', 'spi/topic/mpc52xx', 'spi/topic/mxs', 'spi/topic/nuc900', 'spi/topic/oc-tiny' and 'spi/topic/octeon' into spi-next
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>
2014-02-03spi: delete non-required instances of include <linux/init.h>Paul Gortmaker
None of these files are actually using any __init type directives and hence don't need to include <linux/init.h>. Most are just a left over from __devinit and __cpuinit removal, or simply due to code getting copied from one driver to the next. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-10-14spi: bitbang: Fix checkpatch issueJingoo Han
Fix the following checkpatch warnings WARNING: sizeof *cs should be sizeof(*cs) WARNING: please, no space before tabs WARNING: space prohibited between function name and open parenthesis '(' WARNING: line over 80 characters Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-10-07spi: bitbang: Let spi_bitbang_start() take a reference to masterAxel Lin
Many drivers that use bitbang library have a leak on probe error paths. This is because once a spi_master_get() call succeeds, we need an additional spi_master_put() call to free the memory. Fix this issue by moving the code taking a reference to master to spi_bitbang_start(), so spi_bitbang_start() will take a reference to master on success. With this change, the caller is responsible for calling spi_bitbang_stop() to decrement the reference and spi_master_put() as counterpart of spi_alloc_master() to prevent a memory leak. So now we have below patten for drivers using bitbang library: probe: spi_alloc_master -> Init reference count to 1 spi_bitbang_start -> Increment reference count remove: spi_bitbang_stop -> Decrement reference count spi_master_put -> Decrement reference count (reference count reaches 0) Fixup all users accordingly. Signed-off-by: Axel Lin <axel.lin@ingics.com> Suggested-by: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de> Acked-by: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-09-06Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree from Jiri Kosina: "The usual trivial updates all over the tree -- mostly typo fixes and documentation updates" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (52 commits) doc: Documentation/cputopology.txt fix typo treewide: Convert retrun typos to return Fix comment typo for init_cma_reserved_pageblock Documentation/trace: Correcting and extending tracepoint documentation mm/hotplug: fix a typo in Documentation/memory-hotplug.txt power: Documentation: Update s2ram link doc: fix a typo in Documentation/00-INDEX Documentation/printk-formats.txt: No casts needed for u64/s64 doc: Fix typo "is is" in Documentations treewide: Fix printks with 0x%# zram: doc fixes Documentation/kmemcheck: update kmemcheck documentation doc: documentation/hwspinlock.txt fix typo PM / Hibernate: add section for resume options doc: filesystems : Fix typo in Documentations/filesystems scsi/megaraid fixed several typos in comments ppc: init_32: Fix error typo "CONFIG_START_KERNEL" treewide: Add __GFP_NOWARN to k.alloc calls with v.alloc fallbacks page_isolation: Fix a comment typo in test_pages_isolated() doc: fix a typo about irq affinity ...
2013-08-20spi/bitbang: trivial: fix doubled word "use"Uwe Kleine-König
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-08-15spi: bitbang: Remove unused tmp variableAxel Lin
Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-08-09spi/bitbang: don't error out if there is no setup callback providedUwe Kleine-König
It's perfectly valid not to have a setup callback when the probe routine does all the needed things. So don't even check for this case and trust the caller. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Mark Brown <broonie@linaro.org>
2013-07-17spi: spi-bitbang: Fix conversion of spi_bitbang_transfer_one()Fabio Estevam
Since commit 2025172e3 (spi/bitbang: Use core message pump), the following kernel crash is seen: Unable to handle kernel NULL pointer dereference at virtual address 0000000d pgd = 80004000 [0000000d] *pgd=00000000 Internal error: Oops: 5 [#1] SMP ARM Modules linked in: CPU: 1 PID: 48 Comm: spi32766 Not tainted 3.11.0-rc1+ #4 task: bfa3e580 ti: bfb90000 task.ti: bfb90000 PC is at spi_bitbang_transfer_one+0x50/0x248 LR is at spi_bitbang_transfer_one+0x20/0x248 ... ,and also the following build warning: drivers/spi/spi-bitbang.c: In function 'spi_bitbang_start': drivers/spi/spi-bitbang.c:436:31: warning: assignment from incompatible pointer type [enabled by default] In order to fix it, we need to change the first parameter of spi_bitbang_transfer_one() to 'struct spi_master *master'. Tested on a mx6qsabrelite by succesfully probing a SPI NOR flash. Signed-off-by: Fabio Estevam <fabio.estevam@freescale.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: Factor out message transfer from message pump loopMark Brown
In order to make it easier to convert to transfer_one_message() lift the code that does the actual message transfer out of the work function that implements the message pump. This should have no functional impact, it's just a simple code motion patch. 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>
2013-02-05Merge branch 'broonie/spi-next' of ↵Grant Likely
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/misc.git Minor features and bug fixes for PXA, OMAP and GPIO deivce drivers and a cosmetic change to the bitbang driver. Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2013-02-05spi: remove check for bits_per_word on transfer from low level driverLaxman Dewangan
The spi core make sure that each transfer structure have the proper setting for bits_per_word before calling low level transfer APIs. Hence it is no more require to check again in low level driver for this field whether this is set correct or not. Removing such code from low level driver. The txx9 change also removes a test for bits_per_word set to 0, and forcing it to 8 in that case. This can also be removed now since spi_setup() ensures spi->bits_per_word is not zero. if (!spi->bits_per_word) spi->bits_per_word = 8; Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2013-01-14spi: bitbang: simplify pointer arithmeticsGuennadi Liakhovetski
Add a pointer variable to make spi_bitbang_start() look simpler. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2012-11-14spi/bitbang: (cosmetic) simplify list manipulationGuennadi Liakhovetski
Use a proper list iterator instead of an open-coded loop and remove a superfluous list head initialisation. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-11-14spi/bitbang: avoid needless loop flow manipulationsGuennadi Liakhovetski
This patch makes a loop look cleaner by replacing a "break" and a "continue" in its body by a single "if". Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-10-31spi: Add module.h to implicit users in drivers/spiPaul Gortmaker
We are clipping down the presence of module.h, since it was everywhere. If you really need it, you better call it out, as per this changeset. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-06-06spi: reorganize driversGrant Likely
Sort the SPI makefile and enforce the naming convention spi_*.c for spi drivers. This change also rolls the contents of atmel_spi.h into the .c file since there is only one user of that particular include file. v2: - Use 'spi-' prefix instead of 'spi_' to match what seems to be be the predominant pattern for subsystem prefixes. - Clean up filenames in Kconfig and header comment blocks Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Linus Walleij <linus.walleij@linaro.org>