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path: root/drivers/dma/mmp_pdma.c
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2016-07-16dmaengine: mmp_pdma: explicitly freeup irqVinod Koul
dmaengine device should explicitly call devm_free_irq() when using devm_request_irq(). The irq is still ON when devices remove is executed and irq should be quiesced before remove is completed. Signed-off-by: Vinod Koul <vinod.koul@intel.com> Acked-by: Zhangfei Gao <zhangfei.gao@linaro.org>
2016-05-03dmaengine: mmp_pdma: Use dma_pool_zallocJulia Lawall
Dma_pool_zalloc combines dma_pool_alloc and memset 0. The semantic patch that makes this transformation is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression d,e; statement S; @@ d = - dma_pool_alloc + dma_pool_zalloc (...); if (!d) S - memset(d, 0, sizeof(*d)); // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-08-05dmaengine: Add an enum for the dmaengine alignment constraintsMaxime Ripard
Most drivers need to set constraints on the buffer alignment for async tx operations. However, even though it is documented, some drivers either use a defined constant that is not matching what the alignment variable expects (like DMA_BUSWIDTH_* constants) or fill the alignment in bytes instead of power of two. Add a new enum for these alignments that matches what the framework expects, and convert the drivers to it. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-04-24Merge branch 'for-linus' of git://git.infradead.org/users/vkoul/slave-dmaLinus Torvalds
Pull slave-dmaengine updates from Vinod Koul: - new drivers for: - Ingenic JZ4780 controller - APM X-Gene controller - Freescale RaidEngine device - Renesas USB Controller - remove device_alloc_chan_resources dummy handlers - sh driver cleanups for peri peri and related emmc and asoc patches as well - fixes and enhancements spread over the drivers * 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma: (59 commits) dmaengine: dw: don't prompt for DW_DMAC_CORE dmaengine: shdmac: avoid unused variable warnings dmaengine: fix platform_no_drv_owner.cocci warnings dmaengine: pch_dma: fix memory leak on failure path in pch_dma_probe() dmaengine: at_xdmac: unlock spin lock before return dmaengine: xgene: devm_ioremap() returns NULL on error dmaengine: xgene: buffer overflow in xgene_dma_init_channels() dmaengine: usb-dmac: Fix dereferencing freed memory 'desc' dmaengine: sa11x0: report slave capabilities to upper layers dmaengine: vdma: Fix compilation warnings dmaengine: fsl_raid: statify fsl_re_chan_probe dmaengine: Driver support for FSL RaidEngine device. dmaengine: xgene_dma_init_ring_mngr() can be static Documentation: dma: Add documentation for the APM X-Gene SoC DMA device DTS binding arm64: dts: Add APM X-Gene SoC DMA device and DMA clock DTS nodes dmaengine: Add support for APM X-Gene SoC DMA engine driver dmaengine: usb-dmac: Add Renesas USB DMA Controller (USB-DMAC) driver dmaengine: renesas,usb-dmac: Add device tree bindings documentation dmaengine: edma: fixed wrongly initialized data parameter to the edma callback dmaengine: ste_dma40: fix implicit conversion ...
2015-03-18dmaengine: constify of_device_id arrayFabian Frederick
of_device_id is always used as const. (See driver.of_match_table and open firmware functions) Signed-off-by: Fabian Frederick <fabf@skynet.be> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-03-05dmaengine: mmp_pdma: fix warning about slave capsRobert Jarzmik
Fix the dmaengine complaint about missing slave caps : - declare the available bus widths - declare the available transfer types - declare the residue calculation type Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-02-23dmaenegine: mmp-pdma: fix irq handler overwrite physical chan issueQiao Zhou
Some dma channels may be reserved for other purpose in other layer, like secure driver in EL2/EL3. PDMA driver can see the interrupt status, but it should not try to handle related interrupt, since it doesn't belong to PDMA driver in kernel. These interrupts should be handled by corresponding client/module.Otherwise, it will overwrite illegal memory and cause unexpected issues, since pdma driver only requests resources for pdma channels. In PDMA driver, the reserved channels are at the end of total 32 channels. If we find interrupt bit index is not smaller than total dma channels, we should ignore it. Signed-off-by: Qiao Zhou <zhouqiao@marvell.com> Acked-by: Zhangfei Gao <zhangfei.gao@linaro.org> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2014-12-22dmaengine: mmp-pdma: Split device_controlMaxime Ripard
Split the device_control callback of the Marvell MMP PDMA driver to make use of the newly introduced callbacks, that will eventually be used to retrieve slave capabilities. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2014-11-06dmaengine: Remove .owner field for driverKiran Padwal
There is no need to init .owner field. Based on the patch from Peter Griffin <peter.griffin@linaro.org> "mmc: remove .owner field for drivers using module_platform_driver" This patch removes the superflous .owner field for drivers which use the module_platform_driver API, as this is overriden in platform_driver_register anyway." Signed-off-by: Kiran Padwal <kiran.padwal@smartplayin.com> [for nvidia] Acked-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2014-08-04dmaengine: Remove the context argument to the prep_dma_cyclic operationLaurent Pinchart
The argument is always set to NULL and never used. Remove it. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2014-05-07dma: mmp_pdma: add support for residue reportingDaniel Mack
A channel can accommodate more than one transaction, each consisting of multiple descriptors, the last of which has the DCMD_ENDIRQEN bit set. In order to report the channel's residue, we hence have to walk the list of running descriptors, look for those which match the cookie, and then try to find the descriptor which defines upper and lower boundaries that embrace the current transport pointer. Once it is found, walk forward until we find the descriptor that tells us about the end of a transaction via a set DCMD_ENDIRQEN bit. Signed-off-by: Daniel Mack <zonque@gmail.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2014-05-02dma: mmp_pdma: Fix physical channel memory allocation sizeLaurent Pinchart
Use sizeof(*var) instead of sizeof(type) when calling devm_k*alloc(). This avoids using the wrong type as was done to allocate the physical channels array. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2014-05-02dma: mmp_pdma: Simplify access to channel drcmr valueLaurent Pinchart
As the physical channel and virtual channel point to each other, pchan->phy->vchan is always equal to pchan. Simplify the code accordingly. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2014-03-06dma: mmp_pdma: add IRQF_SHARED when request irqChao Xie
For some SOCes use mmp_pdma, they have several dma controllers sharing same irq. So add IRQF_SHARED to flag when request irq. It can make multiple controllers share the same irq. Signed-off-by: Chao Xie <chao.xie@marvell.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2014-01-29dmaengine: mmp_pdma: fix mismergeArnd Bergmann
The merge between 2b7f65b11d87f "mmp_pdma: Style neatening" and 8010dad55a0ab0 "dma: add dma_get_any_slave_channel(), for use in of_xlate()" caused a build error by leaving obsolete code in place: mmp_pdma.c: In function 'mmp_pdma_dma_xlate': mmp_pdma.c:909:31: error: 'candidate' undeclared mmp_pdma.c:912:3: error: label 'retry' used but not defined mmp_pdma.c:901:24: warning: unused variable 'c' [-Wunused-variable] This removes the extraneous lines. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2014-01-07Merge branch 'topic/of' into for-linusVinod Koul
Conflicts: drivers/dma/mmp_pdma.c Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-12-16mmp_pdma: Style neateningJoe Perches
Neaten code used as a template for other drivers. Make the code more consistent with kernel styles. o Convert #defines with (1<<foo) to BIT(foo) o Alignment wrapping o Logic inversions to put return at end of functions o Convert devm_kzalloc with multiply to devm_kcalloc o typo of Peripheral fix Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-12-10dma: add dma_get_any_slave_channel(), for use in of_xlate()Stephen Warren
mmp_pdma.c implements a custom of_xlate() function that is 95% identical to what Tegra will need. Create a function to implement the common part, so everyone doesn't just cut/paste the implementation. Cc: Dan Williams <dan.j.williams@intel.com> Cc: Vinod Koul <vinod.koul@intel.com> Cc: Lars-Peter Clausen <lars@metafoo.de> Cc: dmaengine@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-11-28dma: mmp_pdma: add missing platform_set_drvdata() in mmp_pdma_probe()Wei Yongjun
Add missing platform_set_drvdata() in mmp_pdma_probe(), otherwise calling platform_get_drvdata() in mmp_pdma_remove() returns NULL. Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-10-13dma: misc: remove deprecated IRQF_DISABLEDMichael Opdenacker
This patch proposes to remove the use of the IRQF_DISABLED flag It's a NOOP since 2.6.35 and it will be removed one day. Signed-off-by: Michael Opdenacker <michael.opdenacker@free-electrons.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-10-07dma: mmp_pdma: use list_move instead of list_del/list_addWei Yongjun
Using list_move() instead of list_del() + list_add(). Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-08-25dma: mmp_pdma: set DMA_PRIVATEDaniel Mack
As the driver now has its own xlate function and makes use of the dma_get_slave_channel(), we need to manually set the DMA_PRIVATE flags. Drivers which rely on of_dma_simple_xlate() do implicitly the same by going through __dma_request_channel(). Signed-off-by: Daniel Mack <zonque@gmail.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-08-25dma: mmp_pdma: add support for cyclic DMA descriptorsDaniel Mack
Provide a callback to prepare cyclic DMA transfers. This is for instance needed for audio channel transport. Signed-off-by: Daniel Mack <zonque@gmail.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-08-25dma: mmp_pdma: don't clear DCMD_ENDIRQEN at end of pending chainDaniel Mack
In order to fully support multiple transactions per channel, we need to assure we get an interrupt for each completed transaction. That flags bit is also our only way to tell at which descriptor a transaction ends. So, remove the manual clearing of that bit, and then inline the only remaining command that is left in append_pending_queue() for better readability. Signed-off-by: Daniel Mack <zonque@gmail.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-08-25dma: mmp_pdma: only complete one transaction from dma_do_tasklet()Daniel Mack
Currently, when an interrupt has occured for a channel, the tasklet worker code will only look at the very last entry in the running list and complete its cookie, and then dispose the entire running chain. Hence, the first transaction's cookie will never complete. In fact, the interrupt we should handle will be the one related to the first descriptor in the chain with the ENDIRQEN bit set, so complete the second transaction that is in fact still running. As a result, the driver can't currently handle multiple transactions on one chanel, and it's likely that no drivers exist that rely on this feature. Fix this by walking the running_chain and look for the first descriptor that has the interrupt-enable bit set. Only queue descriptors up to that point for completion handling, while leaving the rest intact. Also, only make the channel idle if the list is completely empty after such a cycle. Signed-off-by: Daniel Mack <zonque@gmail.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-08-14dma: mmp: simplify use of devm_ioremap_resourceJulia Lawall
Remove unneeded error handling on the result of a call to platform_get_resource when the value is passed to devm_ioremap_resource. A simplified version of the semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression pdev,res,n,e,e1; expression ret != 0; identifier l; @@ - res = platform_get_resource(pdev, IORESOURCE_MEM, n); ... when != res - if (res == NULL) { ... \(goto l;\|return ret;\) } ... when != res + res = platform_get_resource(pdev, IORESOURCE_MEM, n); e = devm_ioremap_resource(e1, res); // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-08-14dma: mmp_pdma: add support for byte-aligned transfersDaniel Mack
The PXA DMA controller has a DALGN register which allows for byte-aligned DMA transfers. Use it in case any of the transfer descriptors is not aligned to a mask of ~0x7. Signed-off-by: Daniel Mack <zonque@gmail.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-08-14dma: mmp_pdma: remove duplicate assignmentDaniel Mack
The DMA_SLAVE is currently set twice. Signed-off-by: Daniel Mack <zonque@gmail.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-08-14dma: mmp_pdma: print the number of channels at probe timeDaniel Mack
That helps check the provided runtime information. Signed-off-by: Daniel Mack <zonque@gmail.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-08-14dma: mmp_pdma: make the controller a DMA providerDaniel Mack
This patch makes the mmp_pdma controller able to provide DMA resources in DT environments by providing an dma xlate function. of_dma_simple_xlate() isn't used here, because if fails to handle multiple different DMA engines or several instances of the same controller. Instead, a private implementation is provided that makes use of the newly introduced dma_get_slave_channel() call. Signed-off-by: Daniel Mack <zonque@gmail.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-08-14dma: mmp_pdma: add filter functionDaniel Mack
PXA peripherals need to obtain specific DMA request ids which will eventually be stored in the DRCMR register. Currently, clients are expected to store that number inside the slave config block as slave_id, which is unfortunately incompatible with the way DMA resources are handled in DT environments. This patch adds a filter function which stores the filter parameter passed in by of-dma.c into the channel's drcmr register. For backward compatability, cfg->slave_id is still used if set to a non-zero value. Signed-off-by: Daniel Mack <zonque@gmail.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-08-14dma: mmp_pdma: fix maximum transfer lengthDaniel Mack
There's no reason for limiting the maximum transfer length to 0x1000. Take the actual bit mask instead; the PDMA is able to transfer chunks of up to SZ_8K - 1. Signed-off-by: Daniel Mack <zonque@gmail.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-08-14dma: mmp_pdma: refactor unlocking path in lookup_phy()Daniel Mack
As suggested by Ezequiel GarcĂ­a, release the spinlock at the end of the function only, and use a goto for the control flow. Just a minor cleanup. Signed-off-by: Daniel Mack <zonque@gmail.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-08-14dma: mmp_pdma: factor out DRCMR register calculationDaniel Mack
The exact same calculation is done twice, so let's factor it out to a macro. Signed-off-by: Daniel Mack <zonque@gmail.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-08-13dma: mmp_pdma: Staticize mmp_pdma_alloc_descriptor()Jingoo Han
mmp_pdma_alloc_descriptor() is used only in this file. Fix the following sparse warning: drivers/dma/mmp_pdma.c:359:25: warning: symbol 'mmp_pdma_alloc_descriptor' was not declared. Should it be static? Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-08-05dma: mmp_pdma: clear DRCMR when free a phy channelXiang Wang
In mmp pdma, phy channels are allocated/freed dynamically. The mapping from DMA request to DMA channel number in DRCMR should be cleared when a phy channel is freed. Otherwise conflicts will happen when: 1. A is using channel 2 and free it after finished, but A still maps to channel 2 in DRCMR of A. 2. Now another one B gets channel 2. So B maps to channel 2 too in DRCMR of B. In the datasheet, it is described that "Do not map two active requests to the same channel since it produces unpredictable results" and we can observe that during test. Signed-off-by: Xiang Wang <wangx@marvell.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-08-05dma: mmp_pdma: add protect when alloc/free phy channelsXiang Wang
In mmp pdma, phy channels are allocated/freed dynamically and frequently. But no proper protection is added. Conflict will happen when multi-users are requesting phy channels at the same time. Use spinlock to protect. Signed-off-by: Xiang Wang <wangx@marvell.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-08-05mmp_pdma: remove useless use of lockAndy Shevchenko
Accordingly to dma_cookie_status() description locking is not required. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-02-26Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dmaLinus Torvalds
Pull slave-dmaengine updates from Vinod Koul: "This is fairly big pull by my standards as I had missed last merge window. So we have the support for device tree for slave-dmaengine, large updates to dw_dmac driver from Andy for reusing on different architectures. Along with this we have fixes on bunch of the drivers" Fix up trivial conflicts, usually due to #include line movement next to each other. * 'next' of git://git.infradead.org/users/vkoul/slave-dma: (111 commits) Revert "ARM: SPEAr13xx: Pass DW DMAC platform data from DT" ARM: dts: pl330: Add #dma-cells for generic dma binding support DMA: PL330: Register the DMA controller with the generic DMA helpers DMA: PL330: Add xlate function DMA: PL330: Add new pl330 filter for DT case. dma: tegra20-apb-dma: remove unnecessary assignment edma: do not waste memory for dma_mask dma: coh901318: set residue only if dma is in progress dma: coh901318: avoid unbalanced locking dmaengine.h: remove redundant else keyword dma: of-dma: protect list write operation by spin_lock dmaengine: ste_dma40: do not remove descriptors for cyclic transfers dma: of-dma.c: fix memory leakage dw_dmac: apply default dma_mask if needed dmaengine: ioat - fix spare sparse complain dmaengine: move drivers/of/dma.c -> drivers/dma/of-dma.c ioatdma: fix race between updating ioat->head and IOAT_COMPLETION_PENDING dw_dmac: add support for Lynxpoint DMA controllers dw_dmac: return proper residue value dw_dmac: fill individual length of descriptor ...
2013-01-25dma: Convert to devm_ioremap_resource()Thierry Reding
Convert all uses of devm_request_and_ioremap() to the newly introduced devm_ioremap_resource() which provides more consistent error handling. devm_ioremap_resource() provides its own error messages so all explicit error messages can be removed from the failure code paths. Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de> Cc: Vinod Koul <vinod.koul@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-20dma: remove unnecessary null pointer check in mmp_pdma.cCong Ding
the pointer cfg is dereferenced in line 594, so it's no reason to check null again in line 620. Signed-off-by: Cong Ding <dinggnu@gmail.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-01-03Drivers: dma: remove __dev* attributes.Greg Kroah-Hartman
CONFIG_HOTPLUG is going away as an option. As a result, the __dev* markings need to be removed. This change removes the use of __devinit, __devexit_p, __devinitconst, and __devexit from these drivers. Based on patches originally written by Bill Pemberton, but redone by me in order to handle some of the coding style issues better, by hand. Cc: Bill Pemberton <wfp5p@virginia.edu> Cc: Viresh Kumar <viresh.linux@gmail.com> Cc: Dan Williams <djbw@fb.com> Cc: Vinod Koul <vinod.koul@intel.com> Cc: Barry Song <baohua.song@csr.com> Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Cc: Alexander Duyck <alexander.h.duyck@intel.com> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Jassi Brar <jassisinghbrar@gmail.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Bill Pemberton <wfp5p@virginia.edu> Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-28dma: remove use of __devinitBill Pemberton
CONFIG_HOTPLUG is going away as an option so __devinit is no longer needed. Signed-off-by: Bill Pemberton <wfp5p@virginia.edu> Cc: Li Yang <leoli@freescale.com> Cc: Zhang Wei <zw@zh-kernel.org> Cc: Barry Song <baohua.song@csr.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-11-28dma: remove use of __devexit_pBill Pemberton
CONFIG_HOTPLUG is going away as an option so __devexit_p is no longer needed. Signed-off-by: Bill Pemberton <wfp5p@virginia.edu> Acked-by: Barry Song <baohua.song@csr.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-14dmaengine: mmp-pdma supportZhangfei Gao
1. virtual channel vs. physical channel Virtual channel is managed by dmaengine Physical channel handling resource, such as irq Physical channel is alloced dynamically as descending priority, freed immediately when irq done. The availble highest priority physically channel will alwayes be alloced Issue pending list -> alloc highest dma physically channel available -> dma done -> free physically channel 2. list: running list & pending list submit: desc list -> pending list issue_pending_list: if (IDLE) pending list -> running list; free pending list (RUN) irq: free running list (IDLE) check pendlist -> pending list -> running list; free pending list (RUN) 3. irq: Each list generate one irq, calling callback One list may contain several desc chain, in such case, make sure only the last desc list generate irq. 4. async Submit will add desc chain to pending list, which can be multi-called If multi desc chain is submitted, only the last desc would generate irq -> call back If IDLE, issue_pending_list start pending_list, transforming pendlist to running list If RUN, irq will start pending list 5. test 5.1 pxa3xx_nand on pxa910 5.2 insmod dmatest.ko (threads_per_chan=y) By default drivers/dma/dmatest.c test every channel and test memcpy with 1 threads per channel Signed-off-by: Zhangfei Gao <zhangfei.gao@marvell.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>