kernel.git/drivers/dma/at_hdmac.c, branch linux-4.0.y

dmaengine: at_hdmac: Fix calculation of the residual bytes

2015-03-13T09:28:31Z

This patch fixes the following issues regarding to the calculation of the residue: 1. The residue is always calculated for the current transfer even if the cookie is associated to a pending transfer. 2. For scatter/gather DMA the calculation of the residue for the current transfer doesn't include the bytes of the child descriptors that are already transferred. It only calculates the difference between the transfer's total length minus the number of bytes that are already transferred for the current child descriptor. For example: There is a scatter/gather DMA transfer with a total length of 1 MByte. Getting the residue several times while the transfer is running shows something like that: 1: residue = 975584 2: residue = 1002766 3: residue = 992627 4: residue = 983767 5: residue = 985694 6: residue = 1008094 7: residue = 1009741 8: residue = 1011195 3. The driver stores the residue but never resets it when starting a new transfer. For example: If there are two subsequent DMA transfers. The first one with a total length of 1 MByte and the second one with a total length of 1 kByte. Getting the residue for both transfers shows something like that: transfer 1: residue = 975584 transfer 2: residue = 1048380 Changes from V1: * Fixed coding style of the multi-line comments. * Improved accuracy of the residue calculation when the transfer for the first descriptor is active. Changes from V2: * Member 'tx_width' of 'struct at_desc' restored, because the transfer width can't be derived from the source width when using "slave_sg". The transfer width is needed for the calculation of the residue if either the transfer of the first or the last descriptor is in progress. In the case of a "memory_to_memory_sg" transfer (part of this patch series) the transfer width of both descriptors may differ. Thus it is required to additionally set 'tx_width' of the last descriptor. * Added functions for multiply used calculations. Signed-off-by: Torsten Fleischer Acked-by: Nicolas Ferre Signed-off-by: Vinod Koul

dmaengine: at_hdmac: declare slave capabilities

2015-01-13T18:34:02Z

Declare slave capabilities to suppress "this driver doesn't support generic slave capabilities reporting" warning. Signed-off-by: Ludovic Desroches Acked-by: Maxime Ripard Acked-by: Nicolas Ferre Signed-off-by: Vinod Koul

dmaengine: hdmac: Split device_control

2014-12-22T06:58:57Z

Split the device_control callback of the Atmel HDMAC driver to make use of the newly introduced callbacks, that will eventually be used to retrieve slave capabilities. Signed-off-by: Maxime Ripard Acked-by: Nicolas Ferre Signed-off-by: Vinod Koul

dma: at_hdmac: fix invalid remaining bytes detection

2014-08-07T16:22:27Z

Found using smatch: drivers/dma/at_hdmac.c:299 atc_get_bytes_left() warn: unsigned 'atchan->remain_desc' is never less than zero. Signed-off-by: Alexandre Belloni Signed-off-by: Vinod Koul

dmaengine: Remove the context argument to the prep_dma_cyclic operation

2014-08-04T08:11:50Z

The argument is always set to NULL and never used. Remove it. Signed-off-by: Laurent Pinchart Signed-off-by: Vinod Koul

dmaengine: at_hdmac: use tasklet_kill in teardown

2014-03-17T13:03:43Z

As discussed in [1] the tasklet_disable is not a proper function for teardown. We need to ensure irq is disabled, followed by ensuring that don't schedule any more tasklets and then its safe to use tasklet_kill(). Here in at_hdmac driver we use free_irq() before tasklet_kill(). The free_irq() will ensure that the irq is disabled and also wait till all scheduled interrupts are executed by invoking synchronize_irq(). So we need to only do tasklet_kill() after invoking free_irq() [1]: http://lwn.net/Articles/588457/ Reported-by: Thomas Gleixner Acked-by: Nicolas Ferre Reviewed-by: Thomas Gleixner Signed-off-by: Vinod Koul

Merge commit 'dmaengine-3.13-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/dmaengine

2013-11-16T06:32:36Z

Pull dmaengine changes from Dan 1/ Bartlomiej and Dan finalized a rework of the dma address unmap implementation. 2/ In the course of testing 1/ a collection of enhancements to dmatest fell out. Notably basic performance statistics, and fixed / enhanced test control through new module parameters 'run', 'wait', 'noverify', and 'verbose'. Thanks to Andriy and Linus for their review. 3/ Testing the raid related corner cases of 1/ triggered bugs in the recently added 16-source operation support in the ioatdma driver. 4/ Some minor fixes / cleanups to mv_xor and ioatdma. Conflicts: drivers/dma/dmatest.c Signed-off-by: Vinod Koul

dmaengine: remove DMA unmap from drivers

2013-11-14T19:04:38Z

Remove support for DMA unmapping from drivers as it is no longer needed (DMA core code is now handling it). Cc: Vinod Koul Cc: Tomasz Figa Cc: Dave Jiang Signed-off-by: Bartlomiej Zolnierkiewicz Signed-off-by: Kyungmin Park [djbw: fix up chan2parent() unused warning in drivers/dma/dw/core.c] Signed-off-by: Dan Williams

dmaengine: prepare for generic 'unmap' data

2013-11-14T00:25:06Z

Add a hook for a common dma unmap implementation to enable removal of the per driver custom unmap code. (A reworked version of Bartlomiej Zolnierkiewicz's patches to remove the custom callbacks and the size increase of dma_async_tx_descriptor for drivers that don't care about raid). Cc: Vinod Koul Cc: Tomasz Figa Cc: Dave Jiang [bzolnier: prepare pl330 driver for adding missing unmap while at it] Signed-off-by: Bartlomiej Zolnierkiewicz Signed-off-by: Kyungmin Park Signed-off-by: Dan Williams

dmaengine: at_hdma: use DMA_COMPLETE for dma completion status

2013-10-25T05:45:55Z

Acked-by: Dan Williams Acked-by: Linus Walleij Acked-by: Nicolas Ferre Signed-off-by: Vinod Koul