user/sven/linux.git/drivers/dma/dmaengine.c, branch v5.7

dmaengine: fix channel index enumeration

2020-04-27T15:56:23Z

When the channel register code was changed to allow hotplug operations, dynamic indexing wasn't taken into account. When channels are randomly plugged and unplugged out of order, the serial indexing breaks. Convert channel indexing to using IDA tracking in order to allow dynamic assignment. The previous code does not cause any regression bug for existing channel allocation besides idxd driver since the hotplug usage case is only used by idxd at this point. With this change, the chan->idr_ref is also not needed any longer. We can have a device with no channels registered due to hot plug. The channel device release code no longer should attempt to free the dma device id on the last channel release. Fixes: e81274cd6b52 ("dmaengine: add support to dynamic register/unregister of channels") Reported-by: Yixin Zhang Signed-off-by: Dave Jiang Tested-by: Yixin Zhang Link: https://lore.kernel.org/r/158679961260.7674.8485924270472851852.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul

Merge tag 'dmaengine-5.7-rc1' of git://git.infradead.org/users/vkoul/slave-dma

2020-04-02T23:04:42Z

Pull dmaengine updates from Vinod Koul: "Core: - Some code cleanup and optimization in core by Andy - Debugfs support for displaying dmaengine channels by Peter Drivers: - New driver for uniphier-xdmac controller - Updates to stm32 dma, mdma and dmamux drivers and PM support - More updates to idxd drivers - Bunch of changes in tegra-apb driver and cleaning up of pm functions - Bunch of spelling fixes and Replace zero-length array patches - Shutdown hook for fsl-dpaa2-qdma driver - Support for interleaved transfers for ti-edma and virtualization support for k3-dma driver - Support for reset and updates in xilinx_dma driver - Improvements and locking updates in at_hdma driver" * tag 'dmaengine-5.7-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (89 commits) dt-bindings: dma: renesas,usb-dmac: add r8a77961 support dmaengine: uniphier-xdmac: Remove redandant error log for platform_get_irq dmaengine: tegra-apb: Improve DMA synchronization dmaengine: tegra-apb: Don't save/restore IRQ flags in interrupt handler dmaengine: tegra-apb: mark PM functions as __maybe_unused dmaengine: fix spelling mistake "exceds" -> "exceeds" dmaengine: sprd: Set request pending flag when DMA controller is active dmaengine: ppc4xx: Use scnprintf() for avoiding potential buffer overflow dmaengine: idxd: remove global token limit check dmaengine: idxd: reflect shadow copy of traffic class programming dmaengine: idxd: Merge definition of dsa_batch_desc into dsa_hw_desc dmaengine: Create debug directories for DMA devices dmaengine: ti: k3-udma: Implement custom dbg_summary_show for debugfs dmaengine: Add basic debugfs support dmaengine: fsl-dpaa2-qdma: remove set but not used variable 'dpaa2_qdma' dmaengine: ti: edma: fix null dereference because of a typo in pointer name dmaengine: fsl-dpaa2-qdma: Adding shutdown hook dmaengine: uniphier-xdmac: Add UniPhier external DMA controller driver dt-bindings: dmaengine: Add UniPhier external DMA controller bindings dmaengine: ti: k3-udma: Implement support for atype (for virtualization) ...

dmaengine: Create debug directories for DMA devices

2020-03-11T09:26:14Z

Create a placeholder directory for each registered DMA device. DMA drivers can use the dmaengine_get_debugfs_root() call to get their debugfs root and can populate with custom files to aim debugging. Signed-off-by: Peter Ujfalusi Link: https://lore.kernel.org/r/20200306142839.17910-4-peter.ujfalusi@ti.com Signed-off-by: Vinod Koul

dmaengine: Add basic debugfs support

2020-03-11T09:25:10Z

Via the /sys/kernel/debug/dmaengine/summary users can get information about the DMA devices and the used channels. Example output on am654-evm with audio using two channels and after running dmatest on 4 channels: dma0 (285c0000.dma-controller): number of channels: 96 dma1 (31150000.dma-controller): number of channels: 267 dma1chan0 | 2b00000.mcasp:tx dma1chan1 | 2b00000.mcasp:rx dma1chan2 | in-use dma1chan3 | in-use dma1chan4 | in-use dma1chan5 | in-use For slave channels we can show the device and the channel name a given channel is requested. For non slave devices the only information we know is that the channel is in use. DMA drivers can implement the optional dbg_summary_show callback to provide controller specific information instead of the generic one. It is easy to extend the generic dmaengine_summary_show() to print additional information about the used channels. I have taken the idea from gpiolib and clk subsystems. Signed-off-by: Peter Ujfalusi Link: https://lore.kernel.org/r/20200306142839.17910-2-peter.ujfalusi@ti.com Signed-off-by: Vinod Koul

dmaengine: move .device_release missing log warning to debug level

2020-03-11T09:12:59Z

Dmaengine core warns the drivers registering for missing .device_release implementation. The warning is accurate for dmaengine controllers which hotplug but not for rest. So reduce this to a debug log. Link: https://lore.kernel.org/r/20200306135018.2286959-1-vkoul@kernel.org Signed-off-by: Vinod Koul

dmaengine: Cleanups for the slave <-> channel symlink support

2020-02-03T04:19:20Z

No need to use goto to jump over the return chan ? chan : ERR_PTR(-EPROBE_DEFER); We can just revert the check and return right there. Do not fail the channel request if the chan->name allocation fails, but print a warning about it. Change the dev_err to dev_warn if sysfs_create_link() fails as it is not fatal. Only attempt to remove the DMA_SLAVE_NAME symlink if it is created - or it was attempted to be created. Signed-off-by: Peter Ujfalusi Reviewed-by: Geert Uytterhoeven Link: https://lore.kernel.org/r/20200131093859.3311-2-peter.ujfalusi@ti.com Signed-off-by: Vinod Koul

dmaengine: fix null ptr check for __dma_async_device_channel_register()

2020-02-03T04:17:54Z

Add check to pointer after assignment before accessing members. Fixes: d2fb0a043838: ("dmaengine: break out channel registration") Reported-by: Dan Carpenter Signed-off-by: Dave Jiang Link: https://lore.kernel.org/r/158049351973.45445.3291586905226032744.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul

dmaengine: Fix return value for dma_request_chan() in case of failure

2020-01-30T08:23:53Z

Commit 71723a96b8b1 ("dmaengine: Create symlinks between DMA channels and slaves") changed the dma_request_chan() function flow in such a way that it always returns EPROBE_DEFER in case of channels that cannot be found. This break the operation of the devices which have optional DMA channels as it puts their drivers in endless deferred probe loop. Fix this by propagating the proper error value. Fixes: 71723a96b8b1 ("dmaengine: Create symlinks between DMA channels and slaves") Signed-off-by: Marek Szyprowski Reviewed-by: Geert Uytterhoeven Link: https://lore.kernel.org/r/20200130070834.17537-1-m.szyprowski@samsung.com [vkoul: fix typo in patch title] Signed-off-by: Vinod Koul

dmaengine: Create symlinks between DMA channels and slaves

2020-01-24T06:11:32Z

Currently it is not easy to find out which DMA channels are in use, and which slave devices are using which channels. Fix this by creating two symlinks between the DMA channel and the actual slave device when a channel is requested: 1. A "slave" symlink from DMA channel to slave device, 2. A "dma:" symlink slave device to DMA channel. When the channel is released, the symlinks are removed again. The latter requires keeping track of the slave device and the channel name in the dma_chan structure. Note that this is limited to channel request functions for requesting an exclusive slave channel that take a device pointer (dma_request_chan() and dma_request_slave_channel*()). Signed-off-by: Geert Uytterhoeven Tested-by: Niklas Söderlund Link: https://lore.kernel.org/r/20200117153056.31363-1-geert+renesas@glider.be Signed-off-by: Vinod Koul

dmaengine: add support to dynamic register/unregister of channels

2020-01-24T05:48:45Z

With the channel registration routines broken out, now add support code to allow independent registering and unregistering of channels in a hotplug fashion. Signed-off-by: Dave Jiang Link: https://lore.kernel.org/r/157965023364.73301.7821862091077299040.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul