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* spi: Prevent adding devices below an unregistering controllerLukas Wunner2020-12-291-1/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit ddf75be47ca748f8b12d28ac64d624354fddf189 upstream CONFIG_OF_DYNAMIC and CONFIG_ACPI allow adding SPI devices at runtime using a DeviceTree overlay or DSDT patch. CONFIG_SPI_SLAVE allows the same via sysfs. But there are no precautions to prevent adding a device below a controller that's being removed. Such a device is unusable and may not even be able to unbind cleanly as it becomes inaccessible once the controller has been torn down. E.g. it is then impossible to quiesce the device's interrupt. of_spi_notify() and acpi_spi_notify() do hold a ref on the controller, but otherwise run lockless against spi_unregister_controller(). Fix by holding the spi_add_lock in spi_unregister_controller() and bailing out of spi_add_device() if the controller has been unregistered concurrently. Fixes: ce79d54ae447 ("spi/of: Add OF notifier handler") Signed-off-by: Lukas Wunner <lukas@wunner.de> Cc: stable@vger.kernel.org # v3.19+ Cc: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Octavian Purdila <octavian.purdila@intel.com> Cc: Pantelis Antoniou <pantelis.antoniou@konsulko.com> Link: https://lore.kernel.org/r/a8c3205088a969dc8410eec1eba9aface60f36af.1596451035.git.lukas@wunner.de Signed-off-by: Mark Brown <broonie@kernel.org> [sudip: adjust context] Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* spi: Introduce device-managed SPI controller allocationLukas Wunner2020-12-111-1/+53
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 5e844cc37a5cbaa460e68f9a989d321d63088a89 ] SPI driver probing currently comprises two steps, whereas removal comprises only one step: spi_alloc_master() spi_register_master() spi_unregister_master() That's because spi_unregister_master() calls device_unregister() instead of device_del(), thereby releasing the reference on the spi_master which was obtained by spi_alloc_master(). An SPI driver's private data is contained in the same memory allocation as the spi_master struct. Thus, once spi_unregister_master() has been called, the private data is inaccessible. But some drivers need to access it after spi_unregister_master() to perform further teardown steps. Introduce devm_spi_alloc_master(), which releases a reference on the spi_master struct only after the driver has unbound, thereby keeping the memory allocation accessible. Change spi_unregister_master() to not release a reference if the spi_master was allocated by the new devm function. The present commit is small enough to be backportable to stable. It allows fixing drivers which use the private data in their ->remove() hook after it's been freed. It also allows fixing drivers which neglect to release a reference on the spi_master in the probe error path. Long-term, most SPI drivers shall be moved over to the devm function introduced herein. The few that can't shall be changed in a treewide commit to explicitly release the last reference on the master. That commit shall amend spi_unregister_master() to no longer release a reference, thereby completing the migration. As a result, the behaviour will be less surprising and more consistent with subsystems such as IIO, which also includes the private data in the allocation of the generic iio_dev struct, but calls device_del() in iio_device_unregister(). Signed-off-by: Lukas Wunner <lukas@wunner.de> Link: https://lore.kernel.org/r/272bae2ef08abd21388c98e23729886663d19192.1605121038.git.lukas@wunner.de Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* spi: Fix controller unregister order harderLukas Wunner2020-12-111-2/+2
| | | | | | | | | | Commit c7e41e1caa71 sought to backport upstream commit 84855678add8 to the 4.9-stable tree but erroneously inserted a line at the wrong place. Fix it. Fixes: c7e41e1caa71 ("spi: Fix controller unregister order") Reported-by: yangerkun <yangerkun@huawei.com> Signed-off-by: Lukas Wunner <lukas@wunner.de>
* spi: Fix controller unregister orderLukas Wunner2020-06-201-1/+2
| | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 84855678add8aba927faf76bc2f130a40f94b6f7 ] When an SPI controller unregisters, it unbinds all its slave devices. For this, their drivers may need to access the SPI bus, e.g. to quiesce interrupts. However since commit ffbbdd21329f ("spi: create a message queueing infrastructure"), spi_destroy_queue() is executed before unbinding the slaves. It sets ctlr->running = false, thereby preventing SPI bus access and causing unbinding of slave devices to fail. Fix by unbinding slaves before calling spi_destroy_queue(). Fixes: ffbbdd21329f ("spi: create a message queueing infrastructure") Signed-off-by: Lukas Wunner <lukas@wunner.de> Cc: stable@vger.kernel.org # v3.4+ Cc: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/8aaf9d44c153fe233b17bc2dec4eb679898d7e7b.1589557526.git.lukas@wunner.de Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* spi: No need to assign dummy value in spi_unregister_controller()Andy Shevchenko2020-06-201-3/+1
| | | | | | | | | | | | | | | | [ Upstream commit ebc37af5e0a134355ea2b62ed4141458bdbd5389 ] The device_for_each_child() doesn't require the returned value to be checked. Thus, drop the dummy variable completely and have no warning anymore: drivers/spi/spi.c: In function ‘spi_unregister_controller’: drivers/spi/spi.c:2480:6: warning: variable ‘dummy’ set but not used [-Wunused-but-set-variable] int dummy; ^~~~~ Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* spi: Fix zero length xfer bugChris Lesiak2019-05-311-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 5442dcaa0d90fc376bdfc179a018931a8f43dea4 ] This fixes a bug for messages containing both zero length and unidirectional xfers. The function spi_map_msg will allocate dummy tx and/or rx buffers for use with unidirectional transfers when the hardware can only do a bidirectional transfer. That dummy buffer will be used in place of a NULL buffer even when the xfer length is 0. Then in the function __spi_map_msg, if he hardware can dma, the zero length xfer will have spi_map_buf called on the dummy buffer. Eventually, __sg_alloc_table is called and returns -EINVAL because nents == 0. This fix prevents the error by not using the dummy buffer when the xfer length is zero. Signed-off-by: Chris Lesiak <chris.lesiak@licor.com> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
* spi: Fix scatterlist elements size in spi_map_bufMaxime Chevallier2018-04-241-2/+8
| | | | | | | | | | | | | | | | | | | | | | | commit ce99319a182fe766be67f96338386f3ec73e321c upstream. When SPI transfers can be offloaded using DMA, the SPI core need to build a scatterlist to make sure that the buffer to be transferred is dma-able. This patch fixes the scatterlist entry size computation in the case where the maximum acceptable scatterlist entry supported by the DMA controller is less than PAGE_SIZE, when the buffer is vmalloced. For each entry, the actual size is given by the minimum between the desc_len (which is the max buffer size supported by the DMA controller) and the remaining buffer length until we cross a page boundary. Fixes: 65598c13fd66 ("spi: Fix per-page mapping of unaligned vmalloc-ed buffer") Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Signed-off-by: Mark Brown <broonie@kernel.org> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* spi: fix device-node leaksJohan Hovold2017-07-051-2/+6
| | | | | | | | | | | | | commit 8324147f38019865b29d03baf28412d2ec0bd828 upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* spi: When no dma_chan map buffers with spi_master's parentDaniel Kurtz2017-07-051-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 88b0aa544af58ce3be125a1845a227264ec9ab89 upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* spi: double time out toleranceHauke Mehrtens2017-06-291-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | commit 833bfade96561216aa2129516a5926a0326860a2 upstream. 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> Signed-off-by: Amit Pundir <amit.pundir@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* spi: mark device nodes only in case of successful instantiationRalf Ramsauer2016-10-241-1/+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
* kthread: kthread worker API cleanupPetr Mladek2016-10-111-9/+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>
* Merge remote-tracking branch 'spi/topic/dma' into spi-nextMark Brown2016-09-301-3/+14
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| * spi: Add support to handle kmap'd buffers in spi_map_buf()Vignesh R2016-08-171-3/+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>
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*---. \ Merge remote-tracking branches 'spi/fix/lock', 'spi/fix/maintainers', ↵Mark Brown2016-09-061-2/+8
|\ \ \ \ | |_|_|/ |/| | | | | | | 'spi/fix/put', 'spi/fix/pxa2xx', 'spi/fix/sh-msiof' and 'spi/fix/timeout' into spi-linus
| | | * spi: Prevent unexpected SPI time out due to arithmetic overflowSien Wu2016-09-031-2/+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>
| * | spi: Drop io_mutex in error pathsMark Brown2016-08-091-0/+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>
* | Merge tag 'spi-v4.8' of ↵Linus Torvalds2016-07-271-20/+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 ...
| * spi: Split bus and I/O lockingMark Brown2016-07-251-20/+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>
| * spi: Add DMA support for spi_flash_read()Vignesh R2016-06-081-0/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | spi / ACPI: add support for ACPI reconfigure notificationsOctavian Purdila2016-07-081-7/+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>
* Merge remote-tracking branch 'spi/topic/core' into spi-nextMark Brown2016-05-231-2/+5
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| * spi: Fix simple typo s/impelment/implementMoritz Fischer2016-05-041-1/+1
| | | | | | | | | | | | | | 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>
| * spi: return error if kmap'd buffers passed to spi_map_buf()Vignesh R2016-04-251-1/+3
| | | | | | | | | | | | | | | | | | 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>
| * spi: let SPI masters ignore their children for PMLinus Walleij2016-04-121-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | spi: fix possible deadlock between internal bus locks and bus_lock_flagHeiko Stübner2016-03-181-2/+2
|/ | | | | | | | | | | | | 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>
*---. Merge remote-tracking branches 'spi/topic/lp8841', 'spi/topic/msg', ↵Mark Brown2016-03-111-0/+336
|\ \ \ | | | | | | | | | | | | 'spi/topic/pl022' and 'spi/topic/pxa2xx' into spi-next
| | * | spi: Add gfp parameter to kernel-doc to fix build warningJavier Martinez Canillas2016-03-111-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| | * | spi: make xmldocs warning caused by spi.cMasanari Iida2016-02-221-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| | * | spi: docbook: add missing parameter documentationMartin Sperl2016-02-181-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| | * | spi: core: Use min_t(size_t,..)Fabio Estevam2016-02-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| | * | spi: core: Use %zu for printing 'size_t' typeFabio Estevam2016-02-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| | * | spi: core: Staticize __spi_split_transfer_maxsize()Fabio Estevam2016-02-151-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __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>
| | * | spi: checking for NULL instead of IS_ERRDan Carpenter2016-02-121-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| | * | spi: core: add spi_split_transfers_maxsizeMartin Sperl2016-02-091-0/+111
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| | * | spi: core: add spi_replace_transfers methodMartin Sperl2016-02-091-0/+132
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| | * | spi: core: added spi_resource managementMartin Sperl2016-02-091-0/+91
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
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*-. \ \ Merge remote-tracking branches 'spi/topic/doc', 'spi/topic/dw' and ↵Mark Brown2016-03-111-12/+17
|\ \ \ \ | | |/ / | |/| | | | | | 'spi/topic/flash' into spi-next
| | * | spi: core: Fix deadlock when sending messagesJon Hunter2016-03-091-12/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
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*-. | | | Merge remote-tracking branches 'spi/topic/acpi', 'spi/topic/axi-engine', ↵Mark Brown2016-03-111-1/+18
|\ \| | | | | |_|/ | |/| | | | | | 'spi/topic/bcm2835' and 'spi/topic/bcm2835aux' into spi-next
| * | | spi: Let drivers translate ACPI DeviceSelection to suitable Linux chip selectMika Westerberg2016-02-091-1/+18
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | Merge remote-tracking branch 'spi/topic/dma' into spi-nextMark Brown2016-03-111-3/+3
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| * | spi: respect the maximum segment size of DMA deviceAndy Shevchenko2016-03-091-3/+3
| |/ | | | | | | | | | | | | | | 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>
* | spi: Add cond_resched() in main message processing loopMark Brown2016-02-181-0/+3
| | | | | | | | | | | | | | | | | | | | | | 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>
* | spi: introduce accelerated read support for spi flash devicesVignesh R2016-02-091-0/+45
|/ | | | | | | | | | | | | | | | | | | | 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>
* Merge tag 'spi-v4.5' of ↵Linus Torvalds2016-01-131-2/+30
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| *-. Merge remote-tracking branches 'spi/topic/overlay', 'spi/topic/pxa2xx', ↵Mark Brown2016-01-111-0/+29
| |\ \ | | | | | | | | | | | | 'spi/topic/s3c64xx', 'spi/topic/sh-msiof' and 'spi/topic/spidev' into spi-next
| | * | spi: Mark instantiated device nodes with OF_POPULATEGeert Uytterhoeven2015-12-011-2/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| | * | spi: Uninline spi_unregister_device()Geert Uytterhoeven2015-12-011-0/+14
| | |/ | | | | | | | | | | | | | | | | | | | | | 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>
| * | Merge remote-tracking branch 'spi/topic/core' into spi-nextMark Brown2016-01-111-2/+1
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generated by cgit v1.2.3 (git 2.25.1) at 2024-11-29 12:37:21 +0000