When computing the residue we need two pieces of information: the current
descriptor and the remaining data of the current descriptor. To get
that information, we need to read consecutively two registers but we
can't do it in an atomic way. For that reason, we have to check manually
that current descriptor has not changed.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Suggested-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Reported-by: David Engraf <david.engraf@sysgo.com>
Tested-by: David Engraf <david.engraf@sysgo.com>
Fixes: e1f7c9eee707 ("dmaengine: at_xdmac: creation of the atmel
eXtended DMA Controller driver")
Cc: stable@vger.kernel.org #4.1 and later
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Pull dmaengine fixes from Vinod Koul:
 "Here is my second pull request for this window:

  A few driver fixes have piled up and one missed rcar bindings patch
  which got somehow lost in for-linus branch so cherry-picked that one.

  Fixes are for dw, at_hdmac, edma"

* tag 'dmaengine-fix-4.5-rc1' of git://git.infradead.org/users/vkoul/slave-dma:
  dmaengine: rcar-dmac: Document SoC specific bindings
  dmaengine: at_xdmac: fix resume for cyclic transfers
  dmaengine: dw: fix cyclic transfer callbacks
  dmaengine: dw: fix cyclic transfer setup
  dmaengine: edma: Fix paRAM slot allocation for entry channel 0

When having cyclic transfers, the channel was paused when performing
suspend but was not correctly resumed.

Signed-off-by: Songjun Wu <songjun.wu@atmel.com>
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Fixes: e1f7c9eee707 ("dmaengine: at_xdmac: creation of the atmel
eXtended DMA Controller driver")
Cc: <stable@vger.kernel.org> # 4.1 and later
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Pull dmaengine updates from Vinod Koul:
 "This round we have few new features, new driver and updates to few
  drivers.

  The new features to dmaengine core are:
   - Synchronized transfer termination API to terminate the dmaengine
     transfers in synchronized and async fashion as required by users.
     We have its user now in ALSA dmaengine lib, img, at_xdma, axi_dmac
     drivers.
   - Universal API for channel request and start consolidation of
     request flows.  It's user is ompa-dma driver.
   - Introduce reuse of descriptors and use in pxa_dma driver

  Add/Remove:
   - New STM32 DMA driver
   - Removal of unused R-Car HPB-DMAC driver

  Updates:
   - ti-dma-crossbar updates for supporting eDMA
   - tegra-apb pm updates
   - idma64
   - mv_xor updates
   - ste_dma updates"

* tag 'dmaengine-4.5-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (54 commits)
  dmaengine: mv_xor: add suspend/resume support
  dmaengine: mv_xor: de-duplicate mv_chan_set_mode*()
  dmaengine: mv_xor: remove mv_xor_chan->current_type field
  dmaengine: omap-dma: Add support for DMA filter mapping to slave devices
  dmaengine: edma: Add support for DMA filter mapping to slave devices
  dmaengine: core: Introduce new, universal API to request a channel
  dmaengine: core: Move and merge the code paths using private_candidate
  dmaengine: core: Skip mask matching when it is not provided to private_candidate
  dmaengine: mdc: Correct terminate_all handling
  dmaengine: edma: Add probe callback to edma_tptc_driver
  dmaengine: dw: fix potential memory leak in dw_dma_parse_dt()
  dmaengine: stm32-dma: Fix unchecked deference of chan->desc
  dmaengine: sh: Remove unused R-Car HPB-DMAC driver
  dmaengine: usb-dmac: Document SoC specific compatibility strings
  ste_dma40: Delete an unnecessary variable initialisation in d40_probe()
  ste_dma40: Delete another unnecessary check in d40_probe()
  ste_dma40: Delete an unnecessary check before the function call "kmem_cache_destroy"
  dmaengine: tegra-apb: Free interrupts before killing tasklets
  dmaengine: tegra-apb: Update driver to use GFP_NOWAIT
  dmaengine: tegra-apb: Only save channel state for those in use
  ...

This patch fixes at_xdmac_prep_dma_memcpy(). Indeed the data width field
of the Channel Configuration register was not updated properly in the
loop: the bits of the dwidth field were not cleared before adding their
new value.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Fixes: e1f7c9eee70 ("dmaengine: at_xdmac: creation of the atmel eXtended DMA Controller driver")
Cc: stable@vger.kernel.org #4.1 and later
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Calling synchronize_irq() right before free_irq() is quite useless. On one
hand the IRQ can easily fire again before free_irq() is entered, on the
other hand free_irq() itself calls synchronize_irq() internally (in a race
condition free way), before any state associated with the IRQ is freed.

Patch was generated using the following semantic patch:
// <smpl>
@@
expression irq;
@@
-synchronize_irq(irq);
 free_irq(irq, ...);
// </smpl>

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

When performing interleaved transfers with numf > 1, an extra line is
copied. The mbr.bc field is incremented once too often. The length of
the block is (BLEN+1) microblocks.

Signed-off-by: Sylvain ETIENNE <Sylvain.ETIENNE@ingenico.com>
Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Fixes: 4e5385784e69 ("dmaengine: at_xdmac: handle numf > 1")
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

The code was not in agreement with the comments.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Cc: stable@vger.kernel.org # 4.3 and later
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Fix typo in a macro which was not used until now. It explains why there
is no error at compilation time.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Fixes: e1f7c9eee707 "dmaengine: at_xdmac: creation of the atmel eXtended
DMA Controller driver"
Cc: stable@vger.kernel.org # 3.19 and later
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

When setting the channel configuration register, the perid field is not
set to 0 since it is useless for mem2mem transfers. Unfortunately, a
device has 0 as perid. It could cause spurious flags status because
the controller could mix some events from the two channels.
For that reason, use the highest perid value for mem2mem transfers since it
doesn't match the perid of other devices.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>