litmus-rt.git/drivers/dma, branch test

dmaengine: Fix choppy sound because of unimplemented resume

2015-06-12T09:52:26+00:00

Some drivers implement only pause operation (no resuming). Example is
pl330 where pause is needed for getting residuum. pl330 does not support
resume operation, transfer must be stopped after pause.

However for slaves this is exposed always as "pause and resume" which
introduces subtle errors on Odroid U3 board (Exynos4412 with pl330).
After adding pause function to pl330 driver the audio playback
(utilizing DMA) gets choppy after some time (approximately 24 hours).

Fix this by exposing "cmd_pause" if and only if pause and resume are
implemented.

Signed-off-by: Krzysztof Kozlowski 
Reported-by: gabriel@unseen.is
Reported-by: Marek Szyprowski 
Cc: 
Fixes: 88987d2c7534 ("dmaengine: pl330: add DMA_PAUSE feature")
Acked-by: Maxime Ripard 
Signed-off-by: Vinod Koul

dmaengine: at_xdmac: rework slave configuration part

2015-06-08T10:57:09+00:00

Rework slave configuration part in order to more report wrong errors
about the configuration.
Only maxburst and addr width values are checked when doing the slave
configuration. The validity of the channel configuration is done at
prepare time.

Signed-off-by: Ludovic Desroches 
Cc: stable@vger.kernel.org # 4.0 and later
Signed-off-by: Vinod Koul

dmaengine: at_xdmac: lock fixes

2015-06-08T10:57:09+00:00

Using _bh variant for spin locks causes this kind of warning:
Starting logging: ------------[ cut here ]------------
WARNING: CPU: 0 PID: 3 at /ssd_drive/linux/kernel/softirq.c:151
__local_bh_enable_ip+0xe8/0xf4()
Modules linked in:
CPU: 0 PID: 3 Comm: ksoftirqd/0 Not tainted 4.1.0-rc2+ #94
Hardware name: Atmel SAMA5
[] (unwind_backtrace) from [] (show_stack+0x10/0x14)
[] (show_stack) from []
(warn_slowpath_common+0x80/0xac)
[] (warn_slowpath_common) from []
(warn_slowpath_null+0x1c/0x24)
[] (warn_slowpath_null) from []
(__local_bh_enable_ip+0xe8/0xf4)
[] (__local_bh_enable_ip) from []
(at_xdmac_device_terminate_all+0xf4/0x100)
[] (at_xdmac_device_terminate_all) from []
(atmel_complete_tx_dma+0x34/0xf4)
[] (atmel_complete_tx_dma) from []
(at_xdmac_tasklet+0x14c/0x1ac)
[] (at_xdmac_tasklet) from []
(tasklet_action+0x68/0xb4)
[] (tasklet_action) from []
(__do_softirq+0xfc/0x238)
[] (__do_softirq) from [] (run_ksoftirqd+0x28/0x34)
[] (run_ksoftirqd) from []
(smpboot_thread_fn+0x138/0x18c)
[] (smpboot_thread_fn) from [] (kthread+0xdc/0xf0)
[] (kthread) from [] (ret_from_fork+0x14/0x34)
---[ end trace b57b14a99c1d8812 ]---

It comes from the fact that devices can called some code from the DMA
controller with irq disabled. _bh variant is not intended to be used in
this case since it can enable irqs. Switch to irqsave/irqrestore variant to
avoid this situation.

Signed-off-by: Ludovic Desroches 
Cc: stable@vger.kernel.org # 4.0 and later
Signed-off-by: Vinod Koul

dmaengine: hsu: Fix memory leak when stopping a running transfer

2015-06-02T13:03:08+00:00

The vd->node is removed from the lists when the transfer started so the
vchan_get_all_descriptors() will not find it. This results memory leak.

Signed-off-by: Peter Ujfalusi 
[andy: fix the typo to prevent a compilation error]
Signed-off-by: Andy Shevchenko 
Signed-off-by: Vinod Koul

dmaengine: pl330: Fix hang on dmaengine_terminate_all on certain boards

2015-05-22T12:31:03+00:00

The pl330 device could hang infinitely on certain boards when DMA
channels are terminated.

It was caused by lack of runtime resume when executing
pl330_terminate_all() which calls the _stop() function. _stop() accesses
device register and can loop infinitely while checking for device state.

The hang was confirmed by Dinh Nguyen on Altera SOCFPGA Cyclone V
board during boot. It can be also triggered with:

$ echo 1 > /sys/module/dmatest/parameters/iterations
$ echo dma1chan0 > /sys/module/dmatest/parameters/channel
$ echo 1 > /sys/module/dmatest/parameters/run
$ sleep 1
$ cat /sys/module/dmatest/parameters/run

Reported-by: Dinh Nguyen 
Signed-off-by: Krzysztof Kozlowski 
Fixes: ae43b3289186 ("ARM: 8202/1: dmaengine: pl330: Add runtime Power Management support v12")
Cc: 
Tested-by: Dinh Nguyen 
Signed-off-by: Vinod Koul

dmaengine: increment privatecnt when using dma_get_any_slave_channel

2015-04-29T11:17:57+00:00

Channels allocated via dma_get_any_slave_channel were not increasing
the counter tracking private allocations.  When these channels were
released, privatecnt may erroneously fall to zero.  The DMA device
would then lose its DMA_PRIVATE cap and fail to allocate future private
channels (via private_candidate) as any allocations still outstanding
would incorrectly be seen as public allocations.

Signed-off-by: Christopher Freeman 
Signed-off-by: Vinod Koul

dmaengine: xgene: Set hardware dependency

2015-04-27T03:06:02+00:00

The xgene-dma driver is only useful on X-Gene SoC.

Signed-off-by: Jean Delvare 
Cc: Rameshwar Prasad Sahu 
Cc: Loc Ho 
Cc: Vinod Koul 
Signed-off-by: Vinod Koul

dmaengine: usb-dmac: Protect PM-only functions to kill warning

2015-04-27T03:06:02+00:00

If CONFIG_PM=n:

    drivers/dma/sh/usb-dmac.c:677: warning: ‘usb_dmac_runtime_suspend’ defined but not used
    drivers/dma/sh/usb-dmac.c:688: warning: ‘usb_dmac_runtime_resume’ defined but not used

Protect the unused functions by #ifdef CONFIG_PM to fix this.

Signed-off-by: Geert Uytterhoeven 
Signed-off-by: Vinod Koul

Merge branch 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma

2015-04-24T16:49:37+00:00

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
  ...

dmaengine: hsu: don't prompt for hsu_core part

2015-04-22T16:28:32+00:00

HSU_DMA is selected by the HSU_DMA_PCI driver, this should be user selected
so remove the user prompt for this

Signed-off-by: Vinod Koul 
Signed-off-by: Linus Torvalds