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path: root/drivers/dma/dmaengine.c
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2020-02-03dmaengine: Cleanups for the slave <-> channel symlink supportPeter Ujfalusi
No need to use goto to jump over the return chan ? chan : ERR_PTR(-EPROBE_DEFER); We can just revert the check and return right there. Do not fail the channel request if the chan->name allocation fails, but print a warning about it. Change the dev_err to dev_warn if sysfs_create_link() fails as it is not fatal. Only attempt to remove the DMA_SLAVE_NAME symlink if it is created - or it was attempted to be created. Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/20200131093859.3311-2-peter.ujfalusi@ti.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-03dmaengine: fix null ptr check for __dma_async_device_channel_register()Dave Jiang
Add check to pointer after assignment before accessing members. Fixes: d2fb0a043838: ("dmaengine: break out channel registration") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/158049351973.45445.3291586905226032744.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-01-30dmaengine: Fix return value for dma_request_chan() in case of failureMarek Szyprowski
Commit 71723a96b8b1 ("dmaengine: Create symlinks between DMA channels and slaves") changed the dma_request_chan() function flow in such a way that it always returns EPROBE_DEFER in case of channels that cannot be found. This break the operation of the devices which have optional DMA channels as it puts their drivers in endless deferred probe loop. Fix this by propagating the proper error value. Fixes: 71723a96b8b1 ("dmaengine: Create symlinks between DMA channels and slaves") Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/20200130070834.17537-1-m.szyprowski@samsung.com [vkoul: fix typo in patch title] Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-01-24dmaengine: Create symlinks between DMA channels and slavesGeert Uytterhoeven
Currently it is not easy to find out which DMA channels are in use, and which slave devices are using which channels. Fix this by creating two symlinks between the DMA channel and the actual slave device when a channel is requested: 1. A "slave" symlink from DMA channel to slave device, 2. A "dma:<name>" symlink slave device to DMA channel. When the channel is released, the symlinks are removed again. The latter requires keeping track of the slave device and the channel name in the dma_chan structure. Note that this is limited to channel request functions for requesting an exclusive slave channel that take a device pointer (dma_request_chan() and dma_request_slave_channel*()). Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Link: https://lore.kernel.org/r/20200117153056.31363-1-geert+renesas@glider.be Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-01-24dmaengine: add support to dynamic register/unregister of channelsDave Jiang
With the channel registration routines broken out, now add support code to allow independent registering and unregistering of channels in a hotplug fashion. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/157965023364.73301.7821862091077299040.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-01-24dmaengine: break out channel registrationDave Jiang
In preparation for dynamic channel registration, the code segment that does the channel registration is broken out to its own function. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/157965022778.73301.8929944324898985438.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-01-21dmaengine: Remove dma_device_satisfies_mask() wrapperGeert Uytterhoeven
Commit aa1e6f1a385eb2b0 ("dmaengine: kill struct dma_client and supporting infrastructure") removed the last user of the dma_device_satisfies_mask() wrapper. Remove the wrapper, and rename __dma_device_satisfies_mask() to dma_device_satisfies_mask(), to get rid of one more function starting with a double underscore. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/20200121093311.28639-2-geert+renesas@glider.be Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-01-21dmaengine: Add metadata_ops for dma_async_tx_descriptorPeter Ujfalusi
The metadata is best described as side band data or parameters traveling alongside the data DMAd by the DMA engine. It is data which is understood by the peripheral and the peripheral driver only, the DMA engine see it only as data block and it is not interpreting it in any way. The metadata can be different per descriptor as it is a parameter for the data being transferred. If the DMA supports per descriptor metadata it can implement the attach, get_ptr/set_len callbacks. Client drivers must only use either attach or get_ptr/set_len to avoid misconfiguration. Client driver can check if a given metadata mode is supported by the channel during probe time with dmaengine_is_metadata_mode_supported(chan, DESC_METADATA_CLIENT); dmaengine_is_metadata_mode_supported(chan, DESC_METADATA_ENGINE); and based on this information can use either mode. Wrappers are also added for the metadata_ops. To be used in DESC_METADATA_CLIENT mode: dmaengine_desc_attach_metadata() To be used in DESC_METADATA_ENGINE mode: dmaengine_desc_get_metadata_ptr() dmaengine_desc_set_metadata_len() Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Reviewed-by: Tero Kristo <t-kristo@ti.com> Tested-by: Keerthy <j-keerthy@ti.com> Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com> Link: https://lore.kernel.org/r/20191223110458.30766-5-peter.ujfalusi@ti.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-12-26dmaengine: print more meaningful error messageVinod Koul
error log for dma_channel_table_init() failure pointed a mere "initialization failure", which is not very helpful message, so print additional details like function name and error code. Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-12-26dmaengine: move module_/dma_device_put() after route freeVinod Koul
We call dma_device_put() and module_put() after invoking .device_free_chan_resources callback, but we should also take care of router devices and invoke this after .route_free callback. So move it after .route_free Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-12-24dmaengine: Add reference counting to dma_device structLogan Gunthorpe
Adding a reference count helps drivers to properly implement the unbind while in use case. References are taken and put every time a channel is allocated or freed. Once the final reference is put, the device is removed from the dma_device_list and a release callback function is called to signal the driver to free the memory. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Link: https://lore.kernel.org/r/20191216190120.21374-5-logang@deltatee.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-12-24dmaengine: Move dma_channel_rebalance() infrastructure up in codeLogan Gunthorpe
So it can be called by a release function which is needed higher up in the code. No functional changes intended. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Link: https://lore.kernel.org/r/20191216190120.21374-4-logang@deltatee.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-12-24dmaengine: Call module_put() after device_free_chan_resources()Logan Gunthorpe
The module reference is taken to ensure the callbacks still exist when they are called. If the channel holds the last reference to the module, the module can disappear before device_free_chan_resources() is called and would cause a call into free'd memory. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Link: https://lore.kernel.org/r/20191216190120.21374-3-logang@deltatee.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-12-24dmaengine: Store module owner in dma_device structLogan Gunthorpe
dma_chan_to_owner() dereferences the driver from the struct device to obtain the owner and call module_[get|put](). However, if the backing device is unbound before the dma_device is unregistered, the driver will be cleared and this will cause a NULL pointer dereference. Instead, store a pointer to the owner module in the dma_device struct so the module reference can be properly put when the channel is put, even if the backing device was destroyed first. This change helps to support a safer unbind of DMA engines. If the dma_device is unregistered in the driver's remove function, there's no guarantee that there are no existing clients and a users action may trigger the WARN_ONCE in dma_async_device_unregister() which is unlikely to leave the system in a consistent state. Instead, a better approach is to allow the backing driver to go away and fail any subsequent requests to it. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Link: https://lore.kernel.org/r/20191216190120.21374-2-logang@deltatee.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-07-17Merge tag 'dmaengine-5.3-rc1' of git://git.infradead.org/users/vkoul/slave-dmaLinus Torvalds
Pull dmaengine updates from Vinod Koul: - Add support in dmaengine core to do device node checks for DT devices and update bunch of drivers to use that and remove open coding from drivers - New driver/driver support for new hardware, namely: - MediaTek UART APDMA - Freescale i.mx7ulp edma2 - Synopsys eDMA IP core version 0 - Allwinner H6 DMA - Updates to axi-dma and support for interleaved cyclic transfers - Greg's debugfs return value check removals on drivers - Updates to stm32-dma, hsu, dw, pl330, tegra drivers * tag 'dmaengine-5.3-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (68 commits) dmaengine: Revert "dmaengine: fsl-edma: add i.mx7ulp edma2 version support" dmaengine: at_xdmac: check for non-empty xfers_list before invoking callback Documentation: dmaengine: clean up description of dmatest usage dmaengine: tegra210-adma: remove PM_CLK dependency dmaengine: fsl-edma: add i.mx7ulp edma2 version support dt-bindings: dma: fsl-edma: add new i.mx7ulp-edma dmaengine: fsl-edma-common: version check for v2 instead dmaengine: fsl-edma-common: move dmamux register to another single function dmaengine: fsl-edma: add drvdata for fsl-edma dmaengine: Revert "dmaengine: fsl-edma: support little endian for edma driver" dmaengine: rcar-dmac: Reject zero-length slave DMA requests dmaengine: dw: Enable iDMA 32-bit on Intel Elkhart Lake dmaengine: dw-edma: fix semicolon.cocci warnings dmaengine: sh: usb-dmac: Use [] to denote a flexible array member dmaengine: dmatest: timeout value of -1 should specify infinite wait dmaengine: dw: Distinguish ->remove() between DW and iDMA 32-bit dmaengine: fsl-edma: support little endian for edma driver dmaengine: hsu: Revert "set HSU_CH_MTSR to memory width" dmagengine: pl330: add code to get reset property dt-bindings: pl330: document the optional resets property ...
2019-06-10dmaengine: Grammar s/the its/its/, s/need/needs/Geert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-05-27dmaengine: Add matching device node validation in __dma_request_channel()Baolin Wang
When user try to request one DMA channel by __dma_request_channel(), it won't validate if it is the correct DMA device to request, that will lead each DMA engine driver to validate the correct device node in their filter function if it is necessary. Thus we can add the matching device node validation in the DMA engine core, to remove all of device node validation in the drivers. Tested-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Signed-off-by: Baolin Wang <baolin.wang@linaro.org> Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-05-21treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 7Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details the full gnu general public license is included in this distribution in the file called copying extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 9 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Steve Winslow <swinslow@gmail.com> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Jilayne Lovejoy <opensource@jilayne.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190519154041.244154651@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-05mm: replace all open encodings for NUMA_NO_NODEAnshuman Khandual
Patch series "Replace all open encodings for NUMA_NO_NODE", v3. All these places for replacement were found by running the following grep patterns on the entire kernel code. Please let me know if this might have missed some instances. This might also have replaced some false positives. I will appreciate suggestions, inputs and review. 1. git grep "nid == -1" 2. git grep "node == -1" 3. git grep "nid = -1" 4. git grep "node = -1" This patch (of 2): At present there are multiple places where invalid node number is encoded as -1. Even though implicitly understood it is always better to have macros in there. Replace these open encodings for an invalid node number with the global macro NUMA_NO_NODE. This helps remove NUMA related assumptions like 'invalid node' from various places redirecting them to a common definition. Link: http://lkml.kernel.org/r/1545127933-10711-2-git-send-email-anshuman.khandual@arm.com Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> [ixgbe] Acked-by: Jens Axboe <axboe@kernel.dk> [mtip32xx] Acked-by: Vinod Koul <vkoul@kernel.org> [dmaengine.c] Acked-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc] Acked-by: Doug Ledford <dledford@redhat.com> [drivers/infiniband] Cc: Joseph Qi <jiangqi903@gmail.com> Cc: Hans Verkuil <hverkuil@xs4all.nl> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-08-26Merge branch 'ida-4.19' of git://git.infradead.org/users/willy/linux-daxLinus Torvalds
Pull IDA updates from Matthew Wilcox: "A better IDA API: id = ida_alloc(ida, GFP_xxx); ida_free(ida, id); rather than the cumbersome ida_simple_get(), ida_simple_remove(). The new IDA API is similar to ida_simple_get() but better named. The internal restructuring of the IDA code removes the bitmap preallocation nonsense. I hope the net -200 lines of code is convincing" * 'ida-4.19' of git://git.infradead.org/users/willy/linux-dax: (29 commits) ida: Change ida_get_new_above to return the id ida: Remove old API test_ida: check_ida_destroy and check_ida_alloc test_ida: Convert check_ida_conv to new API test_ida: Move ida_check_max test_ida: Move ida_check_leaf idr-test: Convert ida_check_nomem to new API ida: Start new test_ida module target/iscsi: Allocate session IDs from an IDA iscsi target: fix session creation failure handling drm/vmwgfx: Convert to new IDA API dmaengine: Convert to new IDA API ppc: Convert vas ID allocation to new IDA API media: Convert entity ID allocation to new IDA API ppc: Convert mmu context allocation to new IDA API Convert net_namespace to new IDA API cb710: Convert to new IDA API rsxx: Convert to new IDA API osd: Convert to new IDA API sd: Convert to new IDA API ...
2018-08-21dmaengine: Convert to new IDA APIMatthew Wilcox
Simpler and shorter code. Signed-off-by: Matthew Wilcox <willy@infradead.org> Acked-by: Vinod Koul <vkoul@kernel.org>
2018-07-30dmaengine: add a new helper dmaenginem_async_device_registerHuang Shijie
This patch adds the dmaenginem_async_device_register for DMA code. Use the Devres to call the release for the DMA engine driver. Signed-off-by: Huang Shijie <sjhuang@iluvatar.ai> Signed-off-by: Vinod Koul <vkoul@kernel.org>
2018-07-25dmaengine: dma_request_chan_by_mask() to handle deferred probingPeter Ujfalusi
If there are no DMA devices registered yet, return with EPROBE_DEFER similarly to the case when requesting a slave channel. Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Signed-off-by: Vinod Koul <vkoul@kernel.org>
2018-07-09dmaengine: add support for reporting pause and resume separatelyMarek Szyprowski
'cmd_pause' DMA channel capability means that respective DMA engine supports both pausing and resuming given DMA channel. However, in some cases it is important to know if DMA channel can be paused without the need to resume it. This is a typical requirement for proper residue reading on transfer timeout in UART drivers. There are also some DMA engines with limited hardware, which doesn't really support resuming. Reporting pause and resume capabilities separately allows UART drivers to properly check for the really required capabilities and operate in DMA mode also in systems with limited DMA hardware. On the other hand drivers, which rely on full channel suspend/resume support, should now check for both 'pause' and 'resume' features. Existing clients of dma_get_slave_caps() have been checked and the only driver which rely on proper channel resuming is soc-generic-dmaengine-pcm driver, which has been updated to check the newly added capability. Existing 'cmd_pause' now only indicates that DMA engine support pausing given DMA channel. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Mark Brown <broonie@kernel.org> Signed-off-by: Vinod Koul <vkoul@kernel.org>
2018-06-15fix a series of Documentation/ broken file name referencesMauro Carvalho Chehab
As files move around, their previous links break. Fix the references for them. Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Acked-by: Jonathan Corbet <corbet@lwn.net>
2017-08-28dmaengine: remove BUG_ON while registering devicesVinod Koul
DMAengine core has BUG_ON to check for mandatory operations and ones based on capabilities, but they use BUG_ON, so remove and move to error returns and logging the errors gracefully Acked-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-08-22dmaengine: remove DMA_SG as it is dead code in kernelDave Jiang
There are no in kernel consumers for DMA_SG op. Removing operation, dead code, and test code in dmatest. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Cc: Gary Hook <gary.hook@amd.com> Cc: Ludovic Desroches <ludovic.desroches@microchip.com> Cc: Kedareswara rao Appana <appana.durga.rao@xilinx.com> Cc: Li Yang <leoyang.li@nxp.com> Cc: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-03-14dmaengine: Fix array index out of bounds warning in __get_unmap_pool()Matthias Kaehlcke
This fixes the following warning when building with clang and CONFIG_DMA_ENGINE_RAID=n : drivers/dma/dmaengine.c:1102:11: error: array index 2 is past the end of the array (which contains 1 element) [-Werror,-Warray-bounds] return &unmap_pool[2]; ^ ~ drivers/dma/dmaengine.c:1083:1: note: array 'unmap_pool' declared here static struct dmaengine_unmap_pool unmap_pool[] = { ^ drivers/dma/dmaengine.c:1104:11: error: array index 3 is past the end of the array (which contains 1 element) [-Werror,-Warray-bounds] return &unmap_pool[3]; ^ ~ drivers/dma/dmaengine.c:1083:1: note: array 'unmap_pool' declared here static struct dmaengine_unmap_pool unmap_pool[] = { Signed-off-by: Matthias Kaehlcke <mka@chromium.org> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-01-02dmaengine: Convert ID allocation to an IDAMatthew Wilcox
dmaengine currently uses an IDR to allocate DMA IDs, but it only needs to know whether IDs are in use or not; the ID to pointer functionality of the IDR is unused. That means it can use the more space-efficient IDA. Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-08-22dmaengine: device must have at least one channelViresh Kumar
The DMA device can't be registered if it doesn't have any channels registered at all. Moreover, it leads to memory leak and is reported by kmemleak as (on 3.10 kernel, and same shall happen on mainline): unreferenced object 0xffffffc09e597240 (size 64): comm "swapper/0", pid 1, jiffies 4294877736 (age 7060.280s) hex dump (first 32 bytes): 00 00 00 00 c0 ff ff ff 30 00 00 ff 00 00 00 ff ........0....... 00 00 00 ff 00 00 00 ff 00 00 00 ff 00 00 00 ff ................ backtrace: [<ffffffc0003079ec>] create_object+0x148/0x2a0 [<ffffffc000cc150c>] kmemleak_alloc+0x80/0xbc [<ffffffc000303a7c>] kmem_cache_alloc_trace+0x120/0x1ac [<ffffffc00054771c>] dma_async_device_register+0x160/0x46c [<ffffffc000548958>] foo_probe+0x1a0/0x264 [<ffffffc0005d6658>] platform_drv_probe+0x14/0x20 [<ffffffc0005d50cc>] driver_probe_device+0x160/0x374 [<ffffffc0005d538c>] __driver_attach+0x60/0x90 [<ffffffc0005d3e78>] bus_for_each_dev+0x7c/0xb0 [<ffffffc0005d4a0c>] driver_attach+0x1c/0x28 [<ffffffc0005d459c>] bus_add_driver+0x124/0x248 [<ffffffc0005d59cc>] driver_register+0x90/0x110 [<ffffffc0005d6bf4>] platform_driver_register+0x58/0x64 [<ffffffc00142a70c>] foo_driver_init+0x10/0x1c [<ffffffc000200878>] do_one_initcall+0xac/0x148 [<ffffffc00140096c>] kernel_init_freeable+0x1a0/0x258 Return -ENODEV from dma_async_device_register() on such a case. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-05-17Merge branch 'topic/core' into for-linusVinod Koul
2016-05-14dmaengine: core: Use IS_ENABLED() instead of checking for built-in or moduleJavier Martinez Canillas
The IS_ENABLED() macro checks if a Kconfig symbol has been enabled either built-in or as a module, use that macro instead of open coding the same. Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-05-12dmaengine: slave means at least one of DMA_SLAVE, DMA_CYCLICAndy Shevchenko
When check for capabilities recognize slave support by either DMA_SLAVE or DMA_CYCLIC bit set. If we don't do that the user can't get a normally worked DMA support for engines that doesn't have one of the mentioned bits set. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-04-13dmaengine: core: Revert back to pr_debug in __dma_request_channel()Jarkko Nikula
Commit ef859312c3a1 ("dmaengine: core: Use dev_ functions for debug and error prints") wasn't quite right in __dma_request_channel() by claiming that all pr_ prints have valid DMA channel pointer. Obviously it is not true as __dma_request_channel() is looking for a channel and returns NULL if it does not find it. Prevent this potential NULL pointer dereference by reverting back to pr_debug(). Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-04-05dmaengine: add DMA_CYCLIC to dma_get_slave_capsVinod Koul
dma_get_slave_caps() API only checked for slave capability where we use slave capabilities for cyclic dma operations as well, so we should add the cyclic case here too. Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-04-04dmaengine: core: Use dev_ functions for debug and error printsJarkko Nikula
According to dmaengine kerneldoc the struct dma_chan has always a non-NULL pointer to DMA device and a test in dma_async_device_register() validates that DMA device must also point to struct device. All pr_ prints except one in dma_channel_table_init() have valid DMA channel or DMA device pointer available which allow convert them to use dev_ functions and thus able to show the associated DMA device. Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-02-09dmaengine: core: expose max burst capability to clientsShawn Lin
This patch add max_burst to dma_get_slave_caps for clients to get the burst capability of slave dma controller. Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> Signed-off-by: Caesar Wang <wxt@rock-chips.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-01-06Merge branch 'topic/async' into for-linusVinod Koul
2016-01-06Merge branch 'topic/univ_api' into for-linusVinod Koul
2015-12-18dmaengine: core: Introduce new, universal API to request a channelPeter Ujfalusi
The two API function can cover most, if not all current APIs used to request a channel. With minimal effort dmaengine drivers, platforms and dmaengine user drivers can be converted to use the two function. struct dma_chan *dma_request_chan_by_mask(const dma_cap_mask_t *mask); To request any channel matching with the requested capabilities, can be used to request channel for memcpy, memset, xor, etc where no hardware synchronization is needed. struct dma_chan *dma_request_chan(struct device *dev, const char *name); To request a slave channel. The dma_request_chan() will try to find the channel via DT, ACPI or in case if the kernel booted in non DT/ACPI mode it will use a filter lookup table and retrieves the needed information from the dma_slave_map provided by the DMA drivers. This legacy mode needs changes in platform code, in dmaengine drivers and finally the dmaengine user drivers can be converted: For each dmaengine driver an array of DMA device, slave and the parameter for the filter function needs to be added: static const struct dma_slave_map da830_edma_map[] = { { "davinci-mcasp.0", "rx", EDMA_FILTER_PARAM(0, 0) }, { "davinci-mcasp.0", "tx", EDMA_FILTER_PARAM(0, 1) }, { "davinci-mcasp.1", "rx", EDMA_FILTER_PARAM(0, 2) }, { "davinci-mcasp.1", "tx", EDMA_FILTER_PARAM(0, 3) }, { "davinci-mcasp.2", "rx", EDMA_FILTER_PARAM(0, 4) }, { "davinci-mcasp.2", "tx", EDMA_FILTER_PARAM(0, 5) }, { "spi_davinci.0", "rx", EDMA_FILTER_PARAM(0, 14) }, { "spi_davinci.0", "tx", EDMA_FILTER_PARAM(0, 15) }, { "da830-mmc.0", "rx", EDMA_FILTER_PARAM(0, 16) }, { "da830-mmc.0", "tx", EDMA_FILTER_PARAM(0, 17) }, { "spi_davinci.1", "rx", EDMA_FILTER_PARAM(0, 18) }, { "spi_davinci.1", "tx", EDMA_FILTER_PARAM(0, 19) }, }; This information is going to be needed by the dmaengine driver, so modification to the platform_data is needed, and the driver map should be added to the pdata of the DMA driver: da8xx_edma0_pdata.slave_map = da830_edma_map; da8xx_edma0_pdata.slavecnt = ARRAY_SIZE(da830_edma_map); The DMA driver then needs to configure the needed device -> filter_fn mapping before it registers with dma_async_device_register() : ecc->dma_slave.filter_map.map = info->slave_map; ecc->dma_slave.filter_map.mapcnt = info->slavecnt; ecc->dma_slave.filter_map.fn = edma_filter_fn; When neither DT or ACPI lookup is available the dma_request_chan() will try to match the requester's device name with the filter_map's list of device names, when a match found it will use the information from the dma_slave_map to get the channel with the dma_get_channel() internal function. Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-12-18dmaengine: core: Move and merge the code paths using private_candidatePeter Ujfalusi
Channel matching with private_candidate() is used in two paths, the error checking is slightly different in them and they are duplicating code also. Move the code under find_candidate() to provide consistent execution and going to allow us to reuse this mode of channel lookup later. Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-12-18dmaengine: core: Skip mask matching when it is not provided to private_candidatePeter Ujfalusi
If mask is NULL skip the mask matching against the DMA device capabilities. Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-11-16dmaengine: enable DMA_CTRL_REUSERobert Jarzmik
In the current state, the capability of transfer reuse can neither be set by a slave dmaengine driver, nor used by a client driver, because the capability is not available to dma_get_slave_caps(). Fix this by adding a way to declare the capability. Fixes: 272420214d26 ("dmaengine: Add DMA_CTRL_REUSE") Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-11-16dmaengine: Add transfer termination synchronization supportLars-Peter Clausen
The DMAengine API has a long standing race condition that is inherent to the API itself. Calling dmaengine_terminate_all() is supposed to stop and abort any pending or active transfers that have previously been submitted. Unfortunately it is possible that this operation races against a currently running (or with some drivers also scheduled) completion callback. Since the API allows dmaengine_terminate_all() to be called from atomic context as well as from within a completion callback it is not possible to synchronize to the execution of the completion callback from within dmaengine_terminate_all() itself. This means that a user of the DMAengine API does not know when it is safe to free resources used in the completion callback, which can result in a use-after-free race condition. This patch addresses the issue by introducing an explicit synchronization primitive to the DMAengine API called dmaengine_synchronize(). The existing dmaengine_terminate_all() is deprecated in favor of dmaengine_terminate_sync() and dmaengine_terminate_async(). The former aborts all pending and active transfers and synchronizes to the current context, meaning it will wait until all running completion callbacks have finished. This means it is only possible to call this function from non-atomic context. The later function does not synchronize, but can still be used in atomic context or from within a complete callback. It has to be followed up by dmaengine_synchronize() before a client can free the resources used in a completion callback. In addition to this the semantics of the device_terminate_all() callback are slightly relaxed by this patch. It is now OK for a driver to only schedule the termination of the active transfer, but does not necessarily have to wait until the DMA controller has completely stopped. The driver must ensure though that the controller has stopped and no longer accesses any memory when the device_synchronize() callback returns. This was in part done since most drivers do not pay attention to this anyway at the moment and to emphasize that this needs to be done when the device_synchronize() callback is implemented. But it also helps with implementing support for devices where stopping the controller can require operations that may sleep. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-11-10Merge tag 'dmaengine-4.4-rc1' of git://git.infradead.org/users/vkoul/slave-dmaLinus Torvalds
Pull dmaengine updates from Vinod Koul: "This time we have a very typical update which is mostly fixes and updates to drivers and no new drivers. - the biggest change is coming from Peter for edma cleanup which even caused some last minute regression, things seem settled now - idma64 and dw updates - iotdma updates - module autoload fixes for various drivers - scatter gather support for hdmac" * tag 'dmaengine-4.4-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (77 commits) dmaengine: edma: Add dummy driver skeleton for edma3-tptc Revert "ARM: DTS: am33xx: Use the new DT bindings for the eDMA3" Revert "ARM: DTS: am437x: Use the new DT bindings for the eDMA3" dmaengine: dw: some Intel devices has no memcpy support dmaengine: dw: platform: provide platform data for Intel dmaengine: dw: don't override platform data with autocfg dmaengine: hdmac: Add scatter-gathered memset support dmaengine: hdmac: factorise memset descriptor allocation dmaengine: virt-dma: Fix kernel-doc annotations ARM: DTS: am437x: Use the new DT bindings for the eDMA3 ARM: DTS: am33xx: Use the new DT bindings for the eDMA3 dmaengine: edma: New device tree binding dmaengine: Kconfig: edma: Select TI_DMA_CROSSBAR in case of ARCH_OMAP dmaengine: ti-dma-crossbar: Add support for crossbar on AM33xx/AM43xx dmaengine: edma: Merge the of parsing functions dmaengine: edma: Do not allocate memory for edma_rsv_info in case of DT boot dmaengine: edma: Refactor the dma device and channel struct initialization dmaengine: edma: Get qDMA channel information from HW also dmaengine: edma: Merge map_dmach_to_queue into assign_channel_eventq dmaengine: edma: Correct PaRAM access function names (_parm_ to _param_) ...
2015-09-30dmaengine: fix balance of privatecntPeter Ujfalusi
dma_release_channel() decrements privatecnt counter and almost all dma_get* function increments it with the exception of dma_get_slave_channel(). In most cases this does not cause issue since normally the channel is not requested and released, but if a driver requests DMA channel via dma_get_slave_channel() and releases the channel the privatecnt will be unbalanced and this will prevent for example getting channel for memcpy. Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-09-21dmaengine: drop null test before destroy functionsJulia Lawall
Remove unneeded NULL test. The semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression x; @@ -if (x != NULL) \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x); // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-08-17dmaengine: fix balance of privatecnt inc/dec operationsRobert Baldyga
This patch increments privatecnt value and set DMA_PRIVATE in device caps in dma_request_slave_channel() function. This is needed to keep privatecnt increment/decrement balance. As function dma_release_channel() decrements privatecnt counter, we need to increment it when channel is requested. Otherwise privatecnt drops into negatives after few dma_release_channel() calls. Reported-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Robert Baldyga <r.baldyga@samsung.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-06-29Merge tag 'dmaengine-4.2-rc1' of git://git.infradead.org/users/vkoul/slave-dmaLinus Torvalds
Pull dmaengine updates from Vinod Koul: "This time we have support for few new devices, few new features and odd fixes spread thru the subsystem. New devices added: - support for CSRatlas7 dma controller - Allwinner H3(sun8i) controller - TI DMA crossbar driver on DRA7x - new pxa driver New features added: - memset support is bought back now that we have a user in xdmac controller - interleaved transfers support different source and destination strides - supporting DMA routers and configuration thru DT - support for reusing descriptors - xdmac memset and interleaved transfer support - hdmac support for interleaved transfers - omap-dma support for memcpy Others: - Constify platform_device_id - mv_xor fixes and improvements" * tag 'dmaengine-4.2-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (46 commits) dmaengine: xgene: fix file permission dmaengine: fsl-edma: clear pending interrupts on initialization dmaengine: xdmac: Add memset support Documentation: dmaengine: document DMA_CTRL_ACK dmaengine: virt-dma: don't always free descriptor upon completion dmaengine: Revert "drivers/dma: remove unused support for MEMSET operations" dmaengine: hdmac: Implement interleaved transfers dmaengine: Move icg helpers to global header dmaengine: mv_xor: improve descriptors list handling and reduce locking dmaengine: mv_xor: Enlarge descriptor pool size dmaengine: mv_xor: add support for a38x command in descriptor mode dmaengine: mv_xor: Rename function for consistent naming dmaengine: mv_xor: bug fix for racing condition in descriptors cleanup dmaengine: pl330: fix wording in mcbufsz message dmaengine: sirf: add CSRatlas7 SoC support dmaengine: xgene-dma: Fix "incorrect type in assignement" warnings dmaengine: fix kernel-doc documentation dmaengine: pxa_dma: add support for legacy transition dmaengine: pxa_dma: add debug information dmaengine: pxa: add pxa dmaengine driver ...
2015-06-25Merge branch 'topic/omap' into for-linusVinod Koul