Commit Graph

189 Commits

Author SHA1 Message Date
Andy Shevchenko 5d7e816e44 dmaengine: Save few bytes and increase readability of dma_request_chan()
Split IS_ERR_OR_NULL() check followed by additional conditional
to two simple conditionals. This increases readability and saves memory:

Function                                     old     new   delta
dma_request_chan                             700     697      -3
Total: Before=10224, After=10221, chg -0.03%

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200828144519.14483-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-09-03 12:22:35 +05:30
Peter Ujfalusi 7547dbd3b1 dmaengine: Mark dma_request_slave_channel() deprecated
New drivers should use dma_request_chan() instead
dma_request_slave_channel()

dma_request_slave_channel() is a simple wrapper for dma_request_chan()
eating up the error code for channel request failure and makes deferred
probing impossible.

Move the dma_request_slave_channel() into the header as inline function,
mark it as deprecated.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20200828110507.22407-1-peter.ujfalusi@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-09-03 12:21:03 +05:30
Serge Semin 3b6d694eb3 dmaengine: Introduce DMA-device device_caps callback
There are DMA devices (like ours version of Synopsys DW DMAC) which have
DMA capabilities non-uniformly redistributed between the device channels.
In order to provide a way of exposing the channel-specific parameters to
the DMA engine consumers, we introduce a new DMA-device callback. In case
if provided it gets called from the dma_get_slave_caps() method and is
able to override the generic DMA-device capabilities.

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200723005848.31907-6-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-07-27 14:30:55 +05:30
Serge Semin b1b40b8fe7 dmaengine: Introduce max SG burst capability
Some devices may lack the support of the hardware accelerated SG list
entries automatic walking through and execution. In this case a burden of
the SG list traversal and DMA engine re-initialization lies on the
DMA engine driver (normally implemented by using a DMA transfer completion
IRQ to recharge the DMA device with a next SG list entry). But such
solution may not be suitable for some DMA consumers. In particular SPI
devices need both Tx and Rx DMA channels work synchronously in order
to avoid the Rx FIFO overflow. In case if Rx DMA channel is paused for
some time while the Tx DMA channel works implicitly pulling data into the
Rx FIFO, the later will be eventually overflown, which will cause the data
loss. So if SG list entries aren't automatically fetched by the DMA
engine, but are one-by-one manually selected for execution in the
ISRs/deferred work/etc., such problem will eventually happen due to the
non-deterministic latencies of the service execution.

In order to let the DMA consumer know about the DMA device capabilities
regarding the hardware accelerated SG list traversal we introduce the
max_sg_burst capability. It is supposed to be initialized by the DMA engine
driver with 0 if there is no limitation of the number of SG entries
atomically executed and with non-zero value if there is such constraints,
so the upper limit is determined by the number set to the property.

Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200723005848.31907-5-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-07-27 14:30:54 +05:30
Serge Semin d97758e048 dmaengine: Introduce min burst length capability
Some hardware aside from default 0/1 may have greater minimum burst
transactions length constraints. Here we introduce the DMA device
and slave capability, which if required can be initialized by the DMA
engine driver with the device-specific value.

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200723005848.31907-4-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-07-27 14:30:54 +05:30
Linus Torvalds c90e7945e3 dmaengine updates for v5.8-rc1
Bunch of updates to drivers like dmatest, dw-edma, ioat,
 mmp-tdma and k3-udma along with Renesas binding update to json-schema
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Merge tag 'dmaengine-5.8-rc1' of git://git.infradead.org/users/vkoul/slave-dma

Pull dmaengine updates from Vinod Koul:
 "A fairly small dmaengine update which includes mostly driver updates
  (dmatest, dw-edma, ioat, mmp-tdma and k3-udma) along with Renesas
  binding update to json-schema"

* tag 'dmaengine-5.8-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (39 commits)
  dmaengine: imx-sdma: initialize all script addresses
  dmaengine: ti: k3-udma: Use proper return code in alloc_chan_resources
  dmaengine: ti: k3-udma: Remove udma_chan.in_ring_cnt
  dmaengine: ti: k3-udma: Add missing dma_sync call for rx flush descriptor
  dmaengine: at_xdmac: Replace zero-length array with flexible-array
  dmaengine: at_hdmac: Replace zero-length array with flexible-array
  dmaengine: qcom: bam_dma: Replace zero-length array with flexible-array
  dmaengine: ti: k3-udma: Use PTR_ERR_OR_ZERO() to simplify code
  dmaengine: moxart-dma: Drop pointless static qualifier in moxart_probe()
  dmaengine: sf-pdma: Simplify the error handling path in 'sf_pdma_probe()'
  dmaengine: qcom_hidma: use true,false for bool variable
  dmaengine: dw-edma: support local dma device transfer semantics
  dmaengine: Fix doc strings to satisfy validation script
  dmaengine: Include dmaengine.h into dmaengine.c
  dmaengine: dmatest: Describe members of struct dmatest_info
  dmaengine: dmatest: Describe members of struct dmatest_params
  dmaengine: dmatest: Allow negative timeout value to specify infinite wait
  Revert "dmaengine: dmatest: timeout value of -1 should specify infinite wait"
  dmaengine: stm32-dma: direct mode support through device tree
  dt-bindings: dma: add direct mode support through device tree in stm32-dma
  ...
2020-06-10 11:03:04 -07:00
Andy Shevchenko 9872e23d68 dmaengine: Fix doc strings to satisfy validation script
The validation kernel doc script complains about undescribed
function parameters

.../dmaengine.c:155: warning: Function parameter or member 'dev' not descr ibed in 'dev_to_dma_chan'
.../dmaengine.c:251: warning: cannot understand function prototype: 'dma_cap_mask_t dma_cap_mask_all; '
.../dmaengine.c:257: warning: cannot understand function prototype: 'struct dma_chan_tbl_ent '
.../dmaengine.c:264: warning: cannot understand function prototype: 'struct dma_chan_tbl_ent __percpu *channel_table[DMA_TX_TYPE_END]; '
.../dmaengine.c:304: warning: Function parameter or member 'chan' not described in 'dma_chan_is_local'
.../dmaengine.c:304: warning: Function parameter or member 'cpu' not described in 'dma_chan_is_local'
.../dmaengine.c:414: warning: Function parameter or member 'chan' not described in 'balance_ref_count'
.../dmaengine.c:447: warning: Function parameter or member 'chan' not described in 'dma_chan_get'
.../dmaengine.c:494: warning: Function parameter or member 'chan' not described in 'dma_chan_put'

Add descriptions to the function parameters and in some cases update
existing text as well.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200429122151.50989-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-05-04 10:58:03 +05:30
Andy Shevchenko 833d88f3fd dmaengine: Include dmaengine.h into dmaengine.c
Compiler is not happy about non-static functions due to missed inclusion

.../dmaengine.c:682:18: warning: no previous prototype for ‘dma_get_slave_channel’ [-Wmissing-prototypes]
  682 | struct dma_chan *dma_get_slave_channel(struct dma_chan *chan)
      |                  ^~~~~~~~~~~~~~~~~~~~~
.../dmaengine.c:713:18: warning: no previous prototype for ‘dma_get_any_slave_channel’ [-Wmissing-prototypes]
  713 | struct dma_chan *dma_get_any_slave_channel(struct dma_device *device)
      |                  ^~~~~~~~~~~~~~~~~~~~~~~~~

Include missed header to satisfy compiler.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200429122151.50989-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-05-04 10:58:03 +05:30
Dave Jiang 0821009445 dmaengine: fix channel index enumeration
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: e81274cd6b ("dmaengine: add support to dynamic register/unregister of channels")

Reported-by: Yixin Zhang <yixin.zhang@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Tested-by: Yixin Zhang <yixin.zhang@intel.com>
Link: https://lore.kernel.org/r/158679961260.7674.8485924270472851852.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-04-27 21:26:23 +05:30
Linus Torvalds e964f1e04a dmaengine updates for v5.7-rc1
- 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
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Merge tag 'dmaengine-5.7-rc1' of git://git.infradead.org/users/vkoul/slave-dma

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)
  ...
2020-04-02 16:04:42 -07:00
Peter Ujfalusi 26cf132de6 dmaengine: Create debug directories for DMA devices
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 <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20200306142839.17910-4-peter.ujfalusi@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-03-11 14:56:14 +05:30
Peter Ujfalusi e937cc1dd7 dmaengine: Add basic debugfs support
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 <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20200306142839.17910-2-peter.ujfalusi@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-03-11 14:55:10 +05:30
Vinod Koul f91da3bd21 dmaengine: move .device_release missing log warning to debug level
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 <vkoul@kernel.org>
2020-03-11 14:42:59 +05:30
Peter Ujfalusi bad83565ea dmaengine: Cleanups for the slave <-> channel symlink support
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 <peter.ujfalusi@ti.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200131093859.3311-2-peter.ujfalusi@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-03 09:49:20 +05:30
Dave Jiang 5429b51f60 dmaengine: fix null ptr check for __dma_async_device_channel_register()
Add check to pointer after assignment before accessing members.

Fixes: d2fb0a043838: ("dmaengine: break out channel registration")

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/158049351973.45445.3291586905226032744.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-02-03 09:47:54 +05:30
Marek Szyprowski 474809a28e dmaengine: Fix return value for dma_request_chan() in case of failure
Commit 71723a96b8 ("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: 71723a96b8 ("dmaengine: Create symlinks between DMA channels and slaves")
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200130070834.17537-1-m.szyprowski@samsung.com
[vkoul: fix typo in patch title]
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-01-30 13:53:53 +05:30
Geert Uytterhoeven 71723a96b8 dmaengine: Create symlinks between DMA channels and slaves
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:<name>" 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 <geert+renesas@glider.be>
Tested-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Link: https://lore.kernel.org/r/20200117153056.31363-1-geert+renesas@glider.be
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-01-24 11:41:32 +05:30
Dave Jiang e81274cd6b dmaengine: add support to dynamic register/unregister of channels
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 <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/157965023364.73301.7821862091077299040.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-01-24 11:18:45 +05:30
Dave Jiang d2fb0a0438 dmaengine: break out channel registration
In preparation for dynamic channel registration, the code segment that
does the channel registration is broken out to its own function.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/157965022778.73301.8929944324898985438.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-01-24 11:18:45 +05:30
Geert Uytterhoeven 69b1189ba2 dmaengine: Remove dma_device_satisfies_mask() wrapper
Commit aa1e6f1a38 ("dmaengine: kill struct dma_client and
supporting infrastructure") removed the last user of the
dma_device_satisfies_mask() wrapper.

Remove the wrapper, and rename __dma_device_satisfies_mask() to
dma_device_satisfies_mask(), to get rid of one more function starting
with a double underscore.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20200121093311.28639-2-geert+renesas@glider.be
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-01-21 15:05:28 +05:30
Peter Ujfalusi 4db8fd32ed dmaengine: Add metadata_ops for dma_async_tx_descriptor
The metadata is best described as side band data or parameters traveling
alongside the data DMAd by the DMA engine. It is data
which is understood by the peripheral and the peripheral driver only, the
DMA engine see it only as data block and it is not interpreting it in any
way.

The metadata can be different per descriptor as it is a parameter for the
data being transferred.

If the DMA supports per descriptor metadata it can implement the attach,
get_ptr/set_len callbacks.

Client drivers must only use either attach or get_ptr/set_len to avoid
misconfiguration.

Client driver can check if a given metadata mode is supported by the
channel during probe time with
dmaengine_is_metadata_mode_supported(chan, DESC_METADATA_CLIENT);
dmaengine_is_metadata_mode_supported(chan, DESC_METADATA_ENGINE);

and based on this information can use either mode.

Wrappers are also added for the metadata_ops.

To be used in DESC_METADATA_CLIENT mode:
dmaengine_desc_attach_metadata()

To be used in DESC_METADATA_ENGINE mode:
dmaengine_desc_get_metadata_ptr()
dmaengine_desc_set_metadata_len()

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: Tero Kristo <t-kristo@ti.com>
Tested-by: Keerthy <j-keerthy@ti.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Link: https://lore.kernel.org/r/20191223110458.30766-5-peter.ujfalusi@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2020-01-21 11:06:12 +05:30
Vinod Koul 08baca4280 dmaengine: print more meaningful error message
error log for dma_channel_table_init() failure pointed a mere
"initialization failure", which is not very helpful message, so print
additional details like function name and error code.

Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-12-26 10:04:18 +05:30
Vinod Koul 83c77940db dmaengine: move module_/dma_device_put() after route free
We call dma_device_put() and module_put() after invoking
.device_free_chan_resources callback, but we should also take care of
router devices and invoke this after .route_free callback. So move it
after .route_free

Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-12-26 10:03:55 +05:30
Logan Gunthorpe 8ad342a863 dmaengine: Add reference counting to dma_device struct
Adding a reference count helps drivers to properly implement the unbind
while in use case.

References are taken and put every time a channel is allocated or freed.

Once the final reference is put, the device is removed from the
dma_device_list and a release callback function is called to signal
the driver to free the memory.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Link: https://lore.kernel.org/r/20191216190120.21374-5-logang@deltatee.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-12-24 10:18:32 +05:30
Logan Gunthorpe 11a0fd2b3b dmaengine: Move dma_channel_rebalance() infrastructure up in code
So it can be called by a release function which is needed higher up in
the code. No functional changes intended.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Link: https://lore.kernel.org/r/20191216190120.21374-4-logang@deltatee.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-12-24 10:18:32 +05:30
Logan Gunthorpe 686607106f dmaengine: Call module_put() after device_free_chan_resources()
The module reference is taken to ensure the callbacks still exist
when they are called. If the channel holds the last reference to the
module, the module can disappear before device_free_chan_resources() is
called and would cause a call into free'd memory.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Link: https://lore.kernel.org/r/20191216190120.21374-3-logang@deltatee.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-12-24 10:18:32 +05:30
Logan Gunthorpe dae7a589c1 dmaengine: Store module owner in dma_device struct
dma_chan_to_owner() dereferences the driver from the struct device to
obtain the owner and call module_[get|put](). However, if the backing
device is unbound before the dma_device is unregistered, the driver
will be cleared and this will cause a NULL pointer dereference.

Instead, store a pointer to the owner module in the dma_device struct
so the module reference can be properly put when the channel is put, even
if the backing device was destroyed first.

This change helps to support a safer unbind of DMA engines.
If the dma_device is unregistered in the driver's remove function,
there's no guarantee that there are no existing clients and a users
action may trigger the WARN_ONCE in dma_async_device_unregister()
which is unlikely to leave the system in a consistent state.
Instead, a better approach is to allow the backing driver to go away
and fail any subsequent requests to it.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Link: https://lore.kernel.org/r/20191216190120.21374-2-logang@deltatee.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-12-24 10:18:32 +05:30
Linus Torvalds 47ebe00b68 dmaengine updates for v5.3-rc1
- Add support in dmaengine core to do device node checks for DT devices and
    update bunch of drivers to use that and remove open coding from drivers
  - New driver/driver support for new hardware, namely:
    - MediaTek UART APDMA
    - Freescale i.mx7ulp edma2
    - Synopsys eDMA IP core version 0
    - Allwinner H6 DMA
  - Updates to axi-dma and support for interleaved cyclic transfers
  - Greg's debugfs return value check removals on drivers
  - Updates to stm32-dma, hsu, dw, pl330, tegra drivers
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Merge tag 'dmaengine-5.3-rc1' of git://git.infradead.org/users/vkoul/slave-dma

Pull dmaengine updates from Vinod Koul:

 - Add support in dmaengine core to do device node checks for DT devices
   and update bunch of drivers to use that and remove open coding from
   drivers

 - New driver/driver support for new hardware, namely:
     - MediaTek UART APDMA
     - Freescale i.mx7ulp edma2
     - Synopsys eDMA IP core version 0
     - Allwinner H6 DMA

 - Updates to axi-dma and support for interleaved cyclic transfers

 - Greg's debugfs return value check removals on drivers

 - Updates to stm32-dma, hsu, dw, pl330, tegra drivers

* tag 'dmaengine-5.3-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (68 commits)
  dmaengine: Revert "dmaengine: fsl-edma: add i.mx7ulp edma2 version support"
  dmaengine: at_xdmac: check for non-empty xfers_list before invoking callback
  Documentation: dmaengine: clean up description of dmatest usage
  dmaengine: tegra210-adma: remove PM_CLK dependency
  dmaengine: fsl-edma: add i.mx7ulp edma2 version support
  dt-bindings: dma: fsl-edma: add new i.mx7ulp-edma
  dmaengine: fsl-edma-common: version check for v2 instead
  dmaengine: fsl-edma-common: move dmamux register to another single function
  dmaengine: fsl-edma: add drvdata for fsl-edma
  dmaengine: Revert "dmaengine: fsl-edma: support little endian for edma driver"
  dmaengine: rcar-dmac: Reject zero-length slave DMA requests
  dmaengine: dw: Enable iDMA 32-bit on Intel Elkhart Lake
  dmaengine: dw-edma: fix semicolon.cocci warnings
  dmaengine: sh: usb-dmac: Use [] to denote a flexible array member
  dmaengine: dmatest: timeout value of -1 should specify infinite wait
  dmaengine: dw: Distinguish ->remove() between DW and iDMA 32-bit
  dmaengine: fsl-edma: support little endian for edma driver
  dmaengine: hsu: Revert "set HSU_CH_MTSR to memory width"
  dmagengine: pl330: add code to get reset property
  dt-bindings: pl330: document the optional resets property
  ...
2019-07-17 09:55:43 -07:00
Geert Uytterhoeven fe333389cc dmaengine: Grammar s/the its/its/, s/need/needs/
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-06-10 13:20:54 +05:30
Baolin Wang f5151311c3 dmaengine: Add matching device node validation in __dma_request_channel()
When user try to request one DMA channel by __dma_request_channel(), it won't
validate if it is the correct DMA device to request, that will lead each DMA
engine driver to validate the correct device node in their filter function
if it is necessary.

Thus we can add the matching device node validation in the DMA engine core,
to remove all of device node validation in the drivers.

Tested-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2019-05-27 11:23:52 +05:30
Thomas Gleixner 9ab65aff02 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 7
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details the full
  gnu general public license is included in this distribution in the
  file called copying

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 9 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Jilayne Lovejoy <opensource@jilayne.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190519154041.244154651@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 11:28:40 +02:00
Anshuman Khandual 98fa15f34c mm: replace all open encodings for NUMA_NO_NODE
Patch series "Replace all open encodings for NUMA_NO_NODE", v3.

All these places for replacement were found by running the following
grep patterns on the entire kernel code.  Please let me know if this
might have missed some instances.  This might also have replaced some
false positives.  I will appreciate suggestions, inputs and review.

1. git grep "nid == -1"
2. git grep "node == -1"
3. git grep "nid = -1"
4. git grep "node = -1"

This patch (of 2):

At present there are multiple places where invalid node number is
encoded as -1.  Even though implicitly understood it is always better to
have macros in there.  Replace these open encodings for an invalid node
number with the global macro NUMA_NO_NODE.  This helps remove NUMA
related assumptions like 'invalid node' from various places redirecting
them to a common definition.

Link: http://lkml.kernel.org/r/1545127933-10711-2-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>	[ixgbe]
Acked-by: Jens Axboe <axboe@kernel.dk>			[mtip32xx]
Acked-by: Vinod Koul <vkoul@kernel.org>			[dmaengine.c]
Acked-by: Michael Ellerman <mpe@ellerman.id.au>		[powerpc]
Acked-by: Doug Ledford <dledford@redhat.com>		[drivers/infiniband]
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Hans Verkuil <hverkuil@xs4all.nl>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-05 21:07:14 -08:00
Linus Torvalds aba16dc5cf Merge branch 'ida-4.19' of git://git.infradead.org/users/willy/linux-dax
Pull IDA updates from Matthew Wilcox:
 "A better IDA API:

      id = ida_alloc(ida, GFP_xxx);
      ida_free(ida, id);

  rather than the cumbersome ida_simple_get(), ida_simple_remove().

  The new IDA API is similar to ida_simple_get() but better named.  The
  internal restructuring of the IDA code removes the bitmap
  preallocation nonsense.

  I hope the net -200 lines of code is convincing"

* 'ida-4.19' of git://git.infradead.org/users/willy/linux-dax: (29 commits)
  ida: Change ida_get_new_above to return the id
  ida: Remove old API
  test_ida: check_ida_destroy and check_ida_alloc
  test_ida: Convert check_ida_conv to new API
  test_ida: Move ida_check_max
  test_ida: Move ida_check_leaf
  idr-test: Convert ida_check_nomem to new API
  ida: Start new test_ida module
  target/iscsi: Allocate session IDs from an IDA
  iscsi target: fix session creation failure handling
  drm/vmwgfx: Convert to new IDA API
  dmaengine: Convert to new IDA API
  ppc: Convert vas ID allocation to new IDA API
  media: Convert entity ID allocation to new IDA API
  ppc: Convert mmu context allocation to new IDA API
  Convert net_namespace to new IDA API
  cb710: Convert to new IDA API
  rsxx: Convert to new IDA API
  osd: Convert to new IDA API
  sd: Convert to new IDA API
  ...
2018-08-26 11:48:42 -07:00
Matthew Wilcox 485258b448 dmaengine: Convert to new IDA API
Simpler and shorter code.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
Acked-by: Vinod Koul <vkoul@kernel.org>
2018-08-21 23:54:19 -04:00
Huang Shijie f39b948dbe dmaengine: add a new helper dmaenginem_async_device_register
This patch adds the dmaenginem_async_device_register for DMA code.
Use the Devres to call the release for the DMA engine driver.

Signed-off-by: Huang Shijie <sjhuang@iluvatar.ai>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2018-07-30 10:50:22 +05:30
Peter Ujfalusi ec8ca8e3b4 dmaengine: dma_request_chan_by_mask() to handle deferred probing
If there are no DMA devices registered yet, return with EPROBE_DEFER
similarly to the case when requesting a slave channel.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2018-07-25 18:04:15 +05:30
Marek Szyprowski d8095f94e1 dmaengine: add support for reporting pause and resume separately
'cmd_pause' DMA channel capability means that respective DMA engine
supports both pausing and resuming given DMA channel. However, in some
cases it is important to know if DMA channel can be paused without the
need to resume it. This is a typical requirement for proper residue
reading on transfer timeout in UART drivers. There are also some DMA
engines with limited hardware, which doesn't really support resuming.

Reporting pause and resume capabilities separately allows UART drivers to
properly check for the really required capabilities and operate in DMA
mode also in systems with limited DMA hardware. On the other hand drivers,
which rely on full channel suspend/resume support, should now check for
both 'pause' and 'resume' features.

Existing clients of dma_get_slave_caps() have been checked and the only
driver which rely on proper channel resuming is soc-generic-dmaengine-pcm
driver, which has been updated to check the newly added capability.
Existing 'cmd_pause' now only indicates that DMA engine support pausing
given DMA channel.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2018-07-09 22:59:04 +05:30
Mauro Carvalho Chehab 44348e8ac1 fix a series of Documentation/ broken file name references
As files move around, their previous links break. Fix the
references for them.

Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Jonathan Corbet <corbet@lwn.net>
2018-06-15 18:10:01 -03:00
Vinod Koul 3eeb515636 dmaengine: remove BUG_ON while registering devices
DMAengine core has BUG_ON to check for mandatory operations and ones based
on capabilities, but they use BUG_ON, so remove and move to error returns
and logging the errors gracefully

Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-08-28 09:39:46 +05:30
Dave Jiang c678fa6634 dmaengine: remove DMA_SG as it is dead code in kernel
There are no in kernel consumers for DMA_SG op. Removing operation,
dead code, and test code in dmatest.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Gary Hook <gary.hook@amd.com>
Cc: Ludovic Desroches <ludovic.desroches@microchip.com>
Cc: Kedareswara rao Appana <appana.durga.rao@xilinx.com>
Cc: Li Yang <leoyang.li@nxp.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-08-22 09:22:11 +05:30
Matthias Kaehlcke 23f963e91f dmaengine: Fix array index out of bounds warning in __get_unmap_pool()
This fixes the following warning when building with clang and
CONFIG_DMA_ENGINE_RAID=n :

drivers/dma/dmaengine.c:1102:11: error: array index 2 is past the end of the array (which contains 1 element) [-Werror,-Warray-bounds]
                return &unmap_pool[2];
                        ^          ~
drivers/dma/dmaengine.c:1083:1: note: array 'unmap_pool' declared here
static struct dmaengine_unmap_pool unmap_pool[] = {
^
drivers/dma/dmaengine.c:1104:11: error: array index 3 is past the end of the array (which contains 1 element) [-Werror,-Warray-bounds]
                return &unmap_pool[3];
                        ^          ~
drivers/dma/dmaengine.c:1083:1: note: array 'unmap_pool' declared here
static struct dmaengine_unmap_pool unmap_pool[] = {

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-03-14 10:11:27 +05:30
Matthew Wilcox adc064cd9f dmaengine: Convert ID allocation to an IDA
dmaengine currently uses an IDR to allocate DMA IDs, but it only needs
to know whether IDs are in use or not; the ID to pointer functionality
of the IDR is unused.  That means it can use the more space-efficient IDA.

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-01-02 09:46:32 +05:30
Viresh Kumar 76d7b84bfa dmaengine: device must have at least one channel
The DMA device can't be registered if it doesn't have any channels
registered at all. Moreover, it leads to memory leak and is reported by
kmemleak as (on 3.10 kernel, and same shall happen on mainline):

unreferenced object 0xffffffc09e597240 (size 64):
  comm "swapper/0", pid 1, jiffies 4294877736 (age 7060.280s)
  hex dump (first 32 bytes):
    00 00 00 00 c0 ff ff ff 30 00 00 ff 00 00 00 ff  ........0.......
    00 00 00 ff 00 00 00 ff 00 00 00 ff 00 00 00 ff  ................
  backtrace:
    [<ffffffc0003079ec>] create_object+0x148/0x2a0
    [<ffffffc000cc150c>] kmemleak_alloc+0x80/0xbc
    [<ffffffc000303a7c>] kmem_cache_alloc_trace+0x120/0x1ac
    [<ffffffc00054771c>] dma_async_device_register+0x160/0x46c
    [<ffffffc000548958>] foo_probe+0x1a0/0x264
    [<ffffffc0005d6658>] platform_drv_probe+0x14/0x20
    [<ffffffc0005d50cc>] driver_probe_device+0x160/0x374
    [<ffffffc0005d538c>] __driver_attach+0x60/0x90
    [<ffffffc0005d3e78>] bus_for_each_dev+0x7c/0xb0
    [<ffffffc0005d4a0c>] driver_attach+0x1c/0x28
    [<ffffffc0005d459c>] bus_add_driver+0x124/0x248
    [<ffffffc0005d59cc>] driver_register+0x90/0x110
    [<ffffffc0005d6bf4>] platform_driver_register+0x58/0x64
    [<ffffffc00142a70c>] foo_driver_init+0x10/0x1c
    [<ffffffc000200878>] do_one_initcall+0xac/0x148
    [<ffffffc00140096c>] kernel_init_freeable+0x1a0/0x258

Return -ENODEV from dma_async_device_register() on such a case.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-08-22 11:49:07 +05:30
Vinod Koul a365c96854 Merge branch 'topic/core' into for-linus 2016-05-17 10:13:40 +05:30
Javier Martinez Canillas d57d3a48ca dmaengine: core: Use IS_ENABLED() instead of checking for built-in or module
The IS_ENABLED() macro checks if a Kconfig symbol has been enabled either
built-in or as a module, use that macro instead of open coding the same.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-05-14 13:32:03 +05:30
Andy Shevchenko dd4e91d538 dmaengine: slave means at least one of DMA_SLAVE, DMA_CYCLIC
When check for capabilities recognize slave support by either DMA_SLAVE or
DMA_CYCLIC bit set. If we don't do that the user can't get a normally worked
DMA support for engines that doesn't have one of the mentioned bits set.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-05-12 11:14:56 +05:30
Jarkko Nikula 4c4d7f8785 dmaengine: core: Revert back to pr_debug in __dma_request_channel()
Commit ef859312c3 ("dmaengine: core: Use dev_ functions for debug and
error prints") wasn't quite right in __dma_request_channel() by claiming
that all pr_ prints have valid DMA channel pointer. Obviously it is not
true as __dma_request_channel() is looking for a channel and returns NULL
if it does not find it.

Prevent this potential NULL pointer dereference by reverting back to
pr_debug().

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-04-13 21:09:21 +05:30
Vinod Koul b2d8984f3e dmaengine: add DMA_CYCLIC to dma_get_slave_caps
dma_get_slave_caps() API only checked for slave capability where
we use slave capabilities for cyclic dma operations as well, so we
should add the cyclic case here too.

Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-04-05 15:31:33 -07:00
Jarkko Nikula ef859312c3 dmaengine: core: Use dev_ functions for debug and error prints
According to dmaengine kerneldoc the struct dma_chan has always a non-NULL
pointer to DMA device and a test in dma_async_device_register()
validates that DMA device must also point to struct device.

All pr_ prints except one in dma_channel_table_init() have valid DMA
channel or DMA device pointer available which allow convert them to use
dev_ functions and thus able to show the associated DMA device.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-04-04 06:19:06 -07:00
Shawn Lin 6d5bbed30f dmaengine: core: expose max burst capability to clients
This patch add max_burst to dma_get_slave_caps for clients
to get the burst capability of slave dma controller.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Caesar Wang <wxt@rock-chips.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2016-02-09 09:01:41 +05:30