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path: root/drivers/dma
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2009-03-28Merge branch 'origin' into develRussell King
Conflicts: sound/soc/pxa/pxa2xx-i2s.c
2009-03-24dma: struct device - replace bus_id with dev_name(), dev_set_name()Kay Sievers
Cc: Dan Williams <dan.j.williams@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
2009-03-13MX31 clkdev supportSascha Hauer
This patch adds clkdev support for i.MX31. This is done in a similar way done previously for i.MX27 Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
2009-03-08Merge branch 'fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx * 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx: dmatest: fix use after free in dmatest_exit ipu_idmac: fix spinlock type iop-adma, mv_xor: fix mem leak on self-test setup failure fsldma: fix off by one in dma_halt I/OAT: fail self-test if callback test reaches timeout I/OAT: update driver version and copyright dates I/OAT: list usage cleanup I/OAT: set tcp_dma_copybreak to 256k for I/OAT ver.3 I/OAT: cancel watchdog before dma remove I/OAT: fail initialization on zero channels detection I/OAT: do not set DCACTRL_CMPL_WRITE_ENABLE for I/OAT ver.3 I/OAT: add verification for proper APICID_TAG_MAP setting by BIOS dmaengine: update kerneldoc
2009-03-04dmatest: fix use after free in dmatest_exitDan Williams
dmatest_cleanup_chanel will free dtc, so grab ->chan before it goes away and use it to do the release. Reported-by: Thierry Reding <thierry.reding@avionic-design.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-04ipu_idmac: fix spinlock typeLuotao Fu
fix a probably accidently dropped reference operator while calling spin_unlock_restore to an ipu lock. Signed-off-by: Luotao Fu <l.fu@pengutronix.de> Cc: Guennadi Liakhovetski <lg@denx.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-04iop-adma, mv_xor: fix mem leak on self-test setup failureRoel Kluin
iop_adma_zero_sum_self_test has the brackets in the wrong place for the setup failure deallocation path. This error was duplicated in mv_xor_xor_self_test. Signed-off-by: Roel Kluin <roel.kluin@gmail.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-04fsldma: fix off by one in dma_haltDan Williams
Prevent dev_err from firing even if we successfully detected 'dma-idle' before the full 1ms timeout has elapsed. Acked-by: Roel Kluin <roel.kluin@gmail.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-04I/OAT: fail self-test if callback test reaches timeoutDan Williams
If we miss interrupts in the self test then fail registration of this channel as it is unsuitable for use as a public channel. Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-04I/OAT: update driver version and copyright datesMaciej Sosnowski
Together with new fixes update driver version and extend copyright dates ranges. Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Shannon Nelson <shannon.nelson@intel.com> Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-04I/OAT: list usage cleanupEric Sesterhenn
Trivial cleanup, list_del(); list_add_tail() is equivalent to list_move_tail(). Semantic patch for coccinelle can be found at www.cccmz.de/~snakebyte/list_move_tail.spatch Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de> Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Shannon Nelson <shannon.nelson@intel.com> Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-04I/OAT: set tcp_dma_copybreak to 256k for I/OAT ver.3Maciej Sosnowski
Upcoming server platforms from Intel based on the Nehalem performance have significantly improved CPU based copy performance. However, the DMA engine can still be effective at higher I/O sizes for TCP traffic and at this time copybreak should be set to 256k for TCP traffic only. Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Shannon Nelson <shannon.nelson@intel.com> Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-04I/OAT: cancel watchdog before dma removeMaciej Sosnowski
Channel watchdog should be canceled before the rest of dma remove stuff. Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Shannon Nelson <shannon.nelson@intel.com> Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-04I/OAT: fail initialization on zero channels detectionMaciej Sosnowski
On some systems with I/OAT ver.2 when DCA is disabled in BIOS situations have been observed that zero DMA channels are detected instead of four. To avoid kernel panic driver should fail gracefully with appropriate message. Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Shannon Nelson <shannon.nelson@intel.com> Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-04I/OAT: do not set DCACTRL_CMPL_WRITE_ENABLE for I/OAT ver.3Maciej Sosnowski
Flag DCACTRL_CMPL_WRITE_ENABLE is valid only for I/OAT ver.2 so it should not be set for I/OAT ver.3. Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Shannon Nelson <shannon.nelson@intel.com> Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-04I/OAT: add verification for proper APICID_TAG_MAP setting by BIOSMaciej Sosnowski
BIOS versions for systems with I/OAT ver.2 have been found which fail to program APICID_TAG_MAP for DCA. The ioatdma driver should recognize incorrectly set APICID_TAG_MAP and disable DCA in that case. Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Shannon Nelson <shannon.nelson@intel.com> Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-03[ARM] fix lots of ARM __devexit sillynessRussell King
`iop_adma_remove' referenced in section `.data' of drivers/built-in.o: defined in discarded section `.devexit.text' of drivers/built-in.o `mv_xor_remove' referenced in section `.data' of drivers/built-in.o: defined in discarded section `.devexit.text' of drivers/built-in.o `mv64xxx_i2c_unmap_regs' referenced in section `.devinit.text' of drivers/built-in.o: defined in discarded section `.devexit.text' of drivers/built-in.o `mv64xxx_i2c_remove' referenced in section `.data' of drivers/built-in.o: defined in discarded section `.devexit.text' of drivers/built-in.o `orion_nand_remove' referenced in section `.data' of drivers/built-in.o: defined in discarded section `.devexit.text' of drivers/built-in.o `pxafb_remove' referenced in section `.data' of drivers/built-in.o: defined in discarded section `.devexit.text' of drivers/built-in.o Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-02-18atmel-mci: fix initialization of dma slave dataDan Williams
The conversion of atmel-mci to dma_request_channel missed the initialization of the channel dma_slave information. The filter_fn passed to dma_request_channel is responsible for initializing the channel's private data. This implementation has the additional benefit of enabling a generic client-channel data passing mechanism. Reviewed-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-19i.MX31: Image Processing Unit DMA and IRQ driversGuennadi Liakhovetski
i.MX3x SoCs contain an Image Processing Unit, consisting of a Control Module (CM), Display Interface (DI), Synchronous Display Controller (SDC), Asynchronous Display Controller (ADC), Image Converter (IC), Post-Filter (PF), Camera Sensor Interface (CSI), and an Image DMA Controller (IDMAC). CM contains, among other blocks, an Interrupt Generator (IG) and a Clock and Reset Control Unit (CRCU). This driver serves IDMAC and IG. They are supported over dmaengine and irq-chip APIs respectively. IDMAC is a specialised DMA controller, its DMA channels cannot be used for general-purpose operations, even though it might be possible to configure a memory-to-memory channel for memcpy operation. This driver will not work with generic dmaengine clients, clients, wishing to use it must use respective wrapper structures, they also must specify which channels they require, as channels are hard-wired to specific IPU functions. Acked-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Guennadi Liakhovetski <lg@denx.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-19dmaengine: kill some dubious WARN_ONCEsDan Williams
dma_find_channel and dma_issue_pending_all are good places to warn about improper api usage. However, warning correctly means synchronizing with dma_list_mutex, i.e. too much overhead for these fast-path calls. Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-15fsldma: print correct IRQ on mpc83xxPeter Korsgaard
The mpc83xx variant uses a shared IRQ for all channels, so the individual channel nodes don't have an interrupt property. Fix the code to print the controller IRQ instead if there isn't any for the channel. Acked-by: Timur Tabi <timur@freescale.com> Acked-by: Li Yang <leoli@freescale.com> Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-14fsldma: check for NO_IRQ in fsl_dma_chan_remove()Peter Korsgaard
There's no per-channel IRQ on mpc83xx, so only call free_irq if we have one. Acked-by: Timur Tabi <timur@freescale.com> Acked-by: Li Yang <leoli@freescale.com> Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-13dmatest: Use custom map/unmap for destination bufferAtsushi Nemoto
The dmatest driver should use DMA_BIDIRECTIONAL on the destination buffer to ensure that the poison values are written to RAM and not just written to cache and discarded. Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-12fsldma: use a valid 'device' for dma_pool_createDan Williams
The dmaengine sysfs implementation was fixed to support proper lifetime rules which means that the current: new_fsl_chan->dev = &new_fsl_chan->common.dev->device; ...retrieves a NULL pointer because new_fsl_chan->common.dev has not been allocated at this point. So, set new_fsl_chan->dev to a valid device. Cc: Li Yang <leoli@freescale.com> Cc: Zhang Wei <zw@zh-kernel.org> Reported-by: Ira Snyder <iws@ovro.caltech.edu> Tested-by: Ira Snyder <iws@ovro.caltech.edu> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-12dmaengine: fix dependency chainingYuri Tikhonov
In dmaengine we track the dependencies between the descriptors using the 'next' pointers of the structure. These pointers are set to NULL as soon as the corresponding descriptor has been submitted to the channel (in dma_run_dependencies()). But, the first 'next' in chain is still remaining set, regardless the fact, that tx->next has been already submitted. This may lead to multiple submissions of the same descriptor. This patch fixes this. Actually, some previous implementation of the xxx_run_dependencies() function already had this fix in place. The fdb..0eaf3 commit, beside the correct things, broke this. Cc: <stable@kernel.org> Signed-off-by: Yuri Tikhonov <yur@emcraft.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06ioat: fix self test for multi-channel caseDan Williams
In the multiple device case we need to re-arm the completion and protect against concurrent self-tests. The printk from the test callback is removed as it can arbitrarily delay completion of the test. Cc: <stable@kernel.org> Cc: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: bump initcall level to arch_initcallDan Williams
There are dmaengine users that would like to register dma devices at subsys_initcall time to ensure channels are available by device_initcall time. Cc: Maciej Sosnowski <maciej.sosnowski@intel.com> Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Cc: Nicolas Ferre <nicolas.ferre@atmel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: advertise all channels on a device to dma_filter_fnDan Williams
Allow dma_filter_fn routines to disambiguate multiple channels on a device rather than assuming that all channels on a device are equal. Cc: Maciej Sosnowski <maciej.sosnowski@intel.com> Reported-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: use idr for registering dma device numbersDan Williams
This brings some predictability to dma device numbers, i.e. an rmmod/insmod cycle may now result in /sys/class/dma/dma0chan0 being restored rather than /sys/class/dma/dma1chan0 appearing. Cc: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: add a release for dma class devices and dependent infrastructureDan Williams
Resolves: WARNING: at drivers/base/core.c:122 device_release+0x4d/0x52() Device 'dma0chan0' does not have a release() function, it is broken and must be fixed. The dma_chan_dev object is introduced to gear-match sysfs kobject and dmaengine channel lifetimes. When a channel is removed access to the sysfs entries return -ENODEV until the kobject can be released. The bulk of the change is updates to existing code to handle the extra layer of indirection between a dma_chan and its struct device. Reported-by: Alexander Beregalov <a.beregalov@gmail.com> Acked-by: Stephen Hemminger <shemminger@vyatta.com> Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06ioat: do not perform removal actions at shutdownDan Williams
Unregistering services should only happen at "remove" time. This prevents the device from being unregistered while dmaengine clients are still active. Also, the comment on ioat_remove is stale since removal is prevented while a channel may be in use. Reported-by: Alexander Beregalov <a.beregalov@gmail.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06iop-adma: enable module removalDan Williams
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06iop-adma: kill debug BUG_ONDan Williams
This BUG_ON caught problems in early development but now it is in the way as it invalidly triggers when trying to remove the module. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06iop-adma: let devm do its job, don't duplicate freeDan Williams
No need to free stuff that the devm infrastructure will take care of... Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: kill enum dma_state_clientDan Williams
DMA_NAK is now useless. We can just use a bool instead. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: remove 'bigref' infrastructureDan Williams
Reference counting is done at the module level so clients need not worry that a channel will leave while they are actively using dmaengine. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: kill struct dma_client and supporting infrastructureDan Williams
All users have been converted to either the general-purpose allocator, dma_find_channel, or dma_request_channel. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: replace dma_async_client_register with dmaengine_getDan Williams
Now that clients no longer need to be notified of channel arrival dma_async_client_register can simply increment the dmaengine_ref_count. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06atmel-mci: convert to dma_request_channel and down-level dma_slaveDan Williams
dma_request_channel provides an exclusive channel, so we no longer need to pass slave data through dmaengine. Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmatest: convert to dma_request_channelDan Williams
Replace the client registration infrastructure with a custom loop to poll for channels. Once dma_request_channel returns NULL stop asking for channels. A userspace side effect of this change if that loading the dmatest module before loading a dma driver will result in no channels being found, previously dmatest would get a callback. To facilitate testing in the built-in case dmatest_init is marked as a late_initcall. Another side effect is that channels under test can not be used for any other purpose. Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: introduce dma_request_channel and private channelsDan Williams
This interface is primarily for device-to-memory clients which need to search for dma channels with platform-specific characteristics. The prototype is: struct dma_chan *dma_request_channel(dma_cap_mask_t mask, dma_filter_fn filter_fn, void *filter_param); When the optional 'filter_fn' parameter is set to NULL dma_request_channel simply returns the first channel that satisfies the capability mask. Otherwise, when the mask parameter is insufficient for specifying the necessary channel, the filter_fn routine can be used to disposition the available channels in the system. The filter_fn routine is called once for each free channel in the system. Upon seeing a suitable channel filter_fn returns DMA_ACK which flags that channel to be the return value from dma_request_channel. A channel allocated via this interface is exclusive to the caller, until dma_release_channel() is called. To ensure that all channels are not consumed by the general-purpose allocator the DMA_PRIVATE capability is provided to exclude a dma_device from general-purpose (memory-to-memory) consideration. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: provide a common 'issue_pending_all' implementationDan Williams
async_tx and net_dma each have open-coded versions of issue_pending_all, so provide a common routine in dmaengine. The implementation needs to walk the global device list, so implement rcu to allow dma_issue_pending_all to run lockless. Clients protect themselves from channel removal events by holding a dmaengine reference. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: centralize channel allocation, introduce dma_find_channelDan Williams
Allowing multiple clients to each define their own channel allocation scheme quickly leads to a pathological situation. For memory-to-memory offload all clients can share a central allocator. This simply moves the existing async_tx allocator to dmaengine with minimal fixups: * async_tx.c:get_chan_ref_by_cap --> dmaengine.c:nth_chan * async_tx.c:async_tx_rebalance --> dmaengine.c:dma_channel_rebalance * split out common code from async_tx.c:__async_tx_find_channel --> dma_find_channel Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06dmaengine: up-level reference counting to the module levelDan Williams
Simply, if a client wants any dmaengine channel then prevent all dmaengine modules from being removed. Once the clients are done re-enable module removal. Why?, beyond reducing complication: 1/ Tracking reference counts per-transaction in an efficient manner, as is currently done, requires a complicated scheme to avoid cache-line bouncing effects. 2/ Per-transaction ref-counting gives the false impression that a dma-driver can be gracefully removed ahead of its user (net, md, or dma-slave) 3/ None of the in-tree dma-drivers talk to hot pluggable hardware, but if such an engine were built one day we still would not need to notify clients of remove events. The driver can simply return NULL to a ->prep() request, something that is much easier for a client to handle. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-05dmaengine: remove dependency on async_txDan Williams
async_tx.ko is a consumer of dma channels. A circular dependency arises if modules in drivers/dma rely on common code in async_tx.ko. It prevents either module from being unloaded. Move dma_wait_for_async_tx and async_tx_run_dependencies to dmaeninge.o where they should have been from the beginning. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-12-08async_xor: dma_map destination DMA_BIDIRECTIONALDan Williams
Mapping the destination multiple times is a misuse of the dma-api. Since the destination may be reused as a source, ensure that it is only mapped once and that it is mapped bidirectionally. This appears to add ugliness on the unmap side in that it always reads back the destination address from the descriptor, but gcc can determine that dma_unmap is a nop and not emit the code that calculates its arguments. Cc: <stable@kernel.org> Cc: Saeed Bishara <saeed@marvell.com> Acked-by: Yuri Tikhonov <yur@emcraft.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-12-03dmaengine: protect 'id' from concurrent registrationsDan Williams
There is a possibility to have two devices registered with the same id. Cc: <stable@kernel.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-12-03ioat: wait for self-test completionDan Williams
As part of the ioat_dma self-test it performs a printk from a completion callback. Depending on the system console configuration this output can take longer than a millisecond causing the self-test to fail. Introduce a completion with a generous timeout to mitigate this failure. Cc: <stable@kernel.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-11-11dmaengine: struct device - replace bus_id with dev_name(), dev_set_name()Kay Sievers
Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-11-11iop-adma: use iop_paranoia() for debug BUG_ONsDan Williams
Now that the critical read back to flush the next descriptor address is fixed we can downgrade some BUG_ONs that need only be enabled when testing changes to the driver. Signed-off-by: Dan Williams <dan.j.williams@intel.com>