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Intel Tangier is known to have the HSU DMA IP as PCI device 00:05.0. The patch
adds the ID as found on Intel Edison board to the PCI device table.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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We want the tty/serial fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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We want the staging tree fixes that are upstream here as well to prevent
merge conflicts from people trying to clean up code.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Now that device_alloc_chan_resources handler in not mandatory, remove dummy
implementations
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Now that device_alloc_chan_resources handler in not mandatory, remove dummy
implementations
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Now that device_alloc_chan_resources handler in not mandatory, remove dummy
implementations
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Now that device_alloc_chan_resources handler in not mandatory, remove dummy
implementations
Acked-by: Zhangfei Gao <zhangfei.gao@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Now that device_alloc_chan_resources handler in not mandatory, remove dummy
implementations
Acked-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Now that device_alloc_chan_resources handler in not mandatory, remove dummy
implementations
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Now that device_alloc_chan_resources handler in not mandatory, remove dummy
implementations
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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The pl330_tx_status() function returns the desc->status if the
dma_cookie_status() call does indicate the cookie completed,
however the desc->status is not look directly compatible. Sparse
throws the following warning:
pl330.c:2262:35: warning: mixing different enum types
pl330.c:2262:35: int enum desc_status versus
pl330.c:2262:35: int enum dma_status
Attempt to fix this by adding a switch statement to turn the
desc->status into a dma_status.
Note, this has only been tested with the dmatest suite.
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
--
Vinod Koul <vinod.koul@intel.com>
Dan Williams <dan.j.williams@intel.com>
DMA List <dmaengine@vger.kernel.org>
Maxime Ripard <maxime.ripard@free-electrons.com>
Jassi Brar <jassisinghbrar@gmail.com>
Liviu Dudau <Liviu.Dudau@arm.com>
Linux ARM Kernel <linux-arm-kernel@lists.infradead.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Whilst running sparse on pl330 driver it was noticed there are
two functions that are not static but not exported to any other
users in the kernel.
Fix the following warnings by making 'pl330_pause' and the
'pl330_get_current_xferred_count' static:
pl330.c:2165:5: warning: symbol 'pl330_pause' was not declared. Should it be static?
pl330.c:2206:5: warning: symbol 'pl330_get_current_xferred_count' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
--
Vinod Koul <vinod.koul@intel.com>
Dan Williams <dan.j.williams@intel.com>
DMA List <dmaengine@vger.kernel.org>
Maxime Ripard <maxime.ripard@free-electrons.com>
Jassi Brar <jassisinghbrar@gmail.com>
Liviu Dudau <Liviu.Dudau@arm.com>
Linux ARM Kernel <linux-arm-kernel@lists.infradead.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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When running Xilinx Zynq in big-endian mode the pl330 driver
fails to pass the dmatest suite. To fix this, ensure all non
byte values are written in little endian.
As a note, the documentation does not mention if it will do
big-endian descriptor fetches, only that it will swap the
data in flight.
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
--
Vinod Koul <vinod.koul@intel.com>
Dan Williams <dan.j.williams@intel.com>
DMA List <dmaengine@vger.kernel.org>
Maxime Ripard <maxime.ripard@free-electrons.com>
Jassi Brar <jassisinghbrar@gmail.com>
Liviu Dudau <Liviu.Dudau@arm.com>
Linux ARM Kernel <linux-arm-kernel@lists.infradead.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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of_device_id is always used as const.
(See driver.of_match_table and open firmware functions)
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Ensure that clients can automatically configure themselves and avoid a
nasty warning at boot by providing capability information.
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Renesas R-Car sound (= rsnd) needs 2 DMAC which are called as
Audio DMAC (= 1st DMAC) and Audio DMAC peri peri (2nd DMAC).
And rsnd had assumed that 1st / 2nd DMACs are implemented as DMAEngine.
But, in result of DMA ML discussion, 2nd DMAC was concluded that it is
not a general purpose DMAC (2nd DMAC is for Device to Device inside
sound system). Additionally, current DMAEngine can't support Device to
Device, and we don't have correct DT bindings for it at this point.
So the easiest solution for it is that move it from DMAEngine to rsnd
driver.
Audio DMAC peri peri on DMAEngine is no longer needed. remove it.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Arnd Bergmann <arnd@arndb.de>
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Currently when version 3.1 of the mx6q SDMA firmware is used we get:
[ 0.392169] imx-sdma 20ec000.sdma: unknown firmware version
[ 0.399281] imx-sdma 20ec000.sdma: initialized
Add support for it.
Based on a patch from Shengjiu Wang from the internal FSL kernel.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Since the last and the only user of this driver is converted to use dw_dmac we
can remove driver from the tree.
Moreover, besides the driver is unmaintained a long time, it serves for the
DesignWare DMA IP, for which we have already driver in the tree.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
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This patch moves the xilinx_dma.h header file
to the include/linux/dma.
Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Free Software Foundation mailing address has been moved in the past and some
of the addresses here are outdated. Remove them from file headers since the
COPYING file in the kernel sources includes it.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Add register offset table entry for the newer (v1.7.0) version of the BAM IP
found on MSM8916. Update the DT bindings documentation.
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Tested-by: Ivan T. Ivanov <iivanov@mm-sol.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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The same error message is printed from different switch cases. Since both of
these jump into same error label we can move error print there and add a DMA
direction in order to make it easier to grep error from sources.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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The same error message is printed from different functions. Add a function
name to error message in order to make it easier to grep error from sources.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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The commit 9cade1a46c77 (dma: dw: split driver to library part and platform
code) introduced a separate platform driver but missed to add a
MODULE_ALIAS("platform:dw_dmac"); to that module.
The patch adds this to get driver loaded automatically if platform device is
registered.
Reported-by: "Blin, Jerome" <jerome.blin@intel.com>
Fixes: 9cade1a46c77 (dma: dw: split driver to library part and platform code)
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Below comments got from Page4724 of Reference Manual of i.mx6q:
http://cache.freescale.com/files/32bit/doc/ref_manual/IMX6DQRM.pdf
--"Static context mode should be used for the first channel called
after reset to ensure that the all context RAM for that channel is
initialized during the context SAVE phase when the channel is
done or yields. Subsequent calls to the same channel or
different channels may use any of the dynamic context modes.
This will ensure that all context locations for the bootload
channel are initialized, and prevent undefined values in context
RAM from being loaded during the context restore if the
channel is re-started later"
Unfortunately, the rule was broken by commit(5b28aa319bba96987316425a1131813d87cbab35)
.This patch just take them back.
Signed-off-by: Robin Gong <b38343@freescale.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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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 <torfl6749@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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This patch adds support for memory to memory scatter-gather transfers.
Changes from V1:
* Fixed coding style of the multi-line comments.
Changes from V2:
* Added setup of 'desc->tx_width' that is needed to calculate the
residue.
Signed-off-by: Torsten Fleischer <torfl6749@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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We want the staging fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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This resolves a merge issue in drivers/tty/serial/8250/8250_pci.c
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Current DMAEngine implementation of DT bindings can't support
DT subnode. This patch export symbols of of_dma_request_slave_channel()
for subnode DMA DT bingings.
ex)
rcar_sound: rcar_sound@ec500000 {
...
rcar_sound,dvc {
dvc0: dvc@0 {
dmas = <&audma0 0xbc>;
dma-names = "tx";
};
dvc1: dvc@1 {
dmas = <&audma0 0xbe>;
dma-names = "tx";
};
};
...
};
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
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The HSU DMA is developed to support High Speed UART controllers found in
particular on Intel MID platforms such as Intel Medfield.
The existing implementation is tighten to the drivers/tty/serial/mfd.c driver
and has a lot of disadvantages. Besides that we would like to get rid of the
old HS UART driver in regarding to extending the 8250 which supports generic
DMAEngine API. That's why the current driver has been developed.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Fix the dmaengine complaint about missing slave caps :
- declare the available bus widths
- declare the available transfer types
- declare the residue calculation type
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Remove double check on chan->desc.
Found by Coccinelle.
Signed-off-by: Tapasweni Pathak <tapaswenipathak@gmail.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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The commit fb93f520e (dmaengine: qcom_bam_dma: Generalize BAM
register offset calculations) wrongly populated base offsets
for event registers for bam v1.4.
Signed-off-by: Stanimir Varbanov <svarbanov@mm-sol.com>
Reviewed-by: Archit Taneja <architt@codeaurora.org>
Reviewed-by: Andy Gross <agross@codeaurora.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Since commit 7bced397510a ("net_dma: simple removal") removed the net_dma
support entirely, net_dma_find_channel has no users left. Remove the function
entirely.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Avoid the warning below triggered during dmaengine async device
registration.
WARNING: CPU: 1 PID: 1 at linux/drivers/dma/dmaengine.c:863
dma_async_device_register+0x2a8/0x4b8()
this driver doesn't support generic slave capabilities reporting
To do that fill mandatory .directions bit mask,
.src/dst_addr_widths and .residue_granularity dma_device fields
with appropriate values.
Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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BDX-DE IOATDMA reports incorrect DMACAP register for PQ related
ops. Ignoring those bits.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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When simplificating the channel configuration, the cyclic case has been
forgotten. It leads to use bad configuration causing many bugs.
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>
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When dma controller is not used by any user and set off,
we should disble interrupt handler, at least the interrupt
reset part, for some subsystem, e.g. ADSP, may use the
dma in its own logic, here reset the interrupt may make
this subsystem work abnormally.
Signed-off-by: Jie Yang <yang.jie@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Below are the refinements.
1. Set DMA abort bit when disabling dma channel. This will clear
the remaining data in dma FIFO, to fix channel-swap issue.
2. Read DMA HW pointer when updating DMA status. Previously dma
position is calculated by adding one period size in dma interrupt.
This is inaccurate/insufficient for some high-quality audio APP.
Since interrupt bottom half handler has variable schedule delay,
it causes big error when calculating sample delay. Read the actual
HW pointer and feedback can improve the accuracy.
3. Do some minor code clean.
Signed-off-by: Qiao Zhou <zhouqiao@marvell.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Fix spelling mistake, "aquire" -> "acquire" and missing newline (as
spotted by Joe Perches.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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During system reboot, the sh-dma-engine device may be runtime-suspended,
causing a crash:
Unhandled fault: imprecise external abort (0x1406) at 0x0002c02c
Internal error: : 1406 [#1] SMP ARM
...
PC is at sh_dmae_ctl_stop+0x28/0x64
LR is at sh_dmae_ctl_stop+0x24/0x64
If the sh-dma-engine is runtime-suspended, its module clock is turned
off, and its registers cannot be accessed.
To fix this, move the call to sh_dmae_ctl_stop(), which touches the
DMAOR register, to the sh_dmae_suspend() and sh_dmae_runtime_suspend()
callbacks. This makes PM operations more symmetric, as both
sh_dmae_resume() and sh_dmae_runtime_resume() already call sh_dmae_rst()
to re-initialize the DMAOR register.
Remove sh_dmae_shutdown(), as it became empty.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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This patch fixes checkpatch.pl error in file ste_dma40.c
ERROR: space required before the open parenthesis '('
Signed-off-by: Dilek Uzulmez <dilekuzulmez@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Some dma channels may be reserved for other purpose in other layer,
like secure driver in EL2/EL3. PDMA driver can see the interrupt
status, but it should not try to handle related interrupt, since it
doesn't belong to PDMA driver in kernel. These interrupts should be
handled by corresponding client/module.Otherwise, it will overwrite
illegal memory and cause unexpected issues, since pdma driver only
requests resources for pdma channels.
In PDMA driver, the reserved channels are at the end of total 32
channels. If we find interrupt bit index is not smaller than total
dma channels, we should ignore it.
Signed-off-by: Qiao Zhou <zhouqiao@marvell.com>
Acked-by: Zhangfei Gao <zhangfei.gao@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Calls tasklet_kill() in error path of the probe function were missing.
Add the same in error path.
Signed-off-by: Pramod Gurav <pramod.gurav@smartplayin.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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in dma_slave_config, which is incompatible with the way that the
dmaengine API normally works.
I've had a closer look at the existing code now and found that all
slave drivers that pass a slave_id in dma_slave_config for SH do that
right after passing the same ID into shdma_chan_filter, so we can just
rely on that. However, the various shdma drivers currently do not
remember the slave ID that was passed into the filter function when
used in non-DT mode and only check the value to find a matching channel,
unlike all other drivers.
There might still be drivers that are not part of the kernel that rely
on setting the slave_id to some other value, so to be on the safe side,
this adds another 'real_slave_id' field to shdma_chan that remembers
the ID and uses it when a driver passes a zero slave_id in dma_slave_config,
like most drivers do.
Eventually, the real_slave_id and slave_id fields should just get merged
into one field, but that requires other changes.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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Pull dmaengine updates from Vinod Koul:
"This update brings:
- the big cleanup up by Maxime for device control and slave
capabilities. This makes the API much cleaner.
- new IMG MDC driver by Andrew
- new Renesas R-Car Gen2 DMA Controller driver by Laurent along with
bunch of fixes on rcar drivers
- odd fixes and updates spread over driver"
* 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma: (130 commits)
dmaengine: pl330: add DMA_PAUSE feature
dmaengine: pl330: improve pl330_tx_status() function
dmaengine: rcar-dmac: Disable channel 0 when using IOMMU
dmaengine: rcar-dmac: Work around descriptor mode IOMMU errata
dmaengine: rcar-dmac: Allocate hardware descriptors with DMAC device
dmaengine: rcar-dmac: Fix oops due to unintialized list in error ISR
dmaengine: rcar-dmac: Fix spinlock issues in interrupt
dmaenegine: edma: fix sparse warnings
dmaengine: rcar-dmac: Fix uninitialized variable usage
dmaengine: shdmac: extend PM methods
dmaengine: shdmac: use SET_RUNTIME_PM_OPS()
dmaengine: pl330: fix bug that cause start the same descs in cyclic
dmaengine: at_xdmac: allow muliple dwidths when doing slave transfers
dmaengine: at_xdmac: simplify channel configuration stuff
dmaengine: at_xdmac: introduce save_cc field
dmaengine: at_xdmac: wait for in-progress transaction to complete after pausing a channel
ioat: fail self-test if wait_for_completion times out
dmaengine: dw: define DW_DMA_MAX_NR_MASTERS
dmaengine: dw: amend description of dma_dev field
dmatest: move src_off, dst_off, len inside loop
...
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git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC cleanups from Olof Johansson:
"This is a good healthy set of various code removals. Total net delta
is 8100 lines removed.
Among the larger cleanups are:
- Removal of old Samsung S3C DMA infrastructure by Arnd
- Removal of the non-DT version of the 'lager' board by Magnus Damm
- General stale code removal on OMAP and Davinci by Rickard Strandqvist
- Removal of non-DT support on am3517 platforms by Tony Lindgren
... plus several other cleanups of various platforms across the board"
* tag 'cleanup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (47 commits)
ARM: sirf: drop redundant function and marco declaration
arm: omap: specify PMUs are for ARMv7 CPUs
arm: shmobile: specify PMUs are for ARMv7 CPUs
arm: iop: specify PMUs are for XScale CPUs
arm: pxa: specify PMUs are for XScale CPUs
arm: realview: specify PMU types
ARM: SAMSUNG: remove unused DMA infrastructure
ARM: OMAP3: Add back Kconfig option MACH_OMAP3517EVM for ASoC
ARM: davinci: Remove CDCE949 driver
ARM: at91: remove useless at91rm9200_set_type()
ARM: at91: remove useless at91rm9200_dt_initialize()
ARM: at91: move debug-macro.S into the common space
ARM: at91: remove useless at91_sysirq_mask_rtx
ARM: at91: remove useless config MACH_AT91SAM9_DT
ARM: at91: remove useless config MACH_AT91RM9200_DT
ARM: at91: remove unused mach/memory.h
ARM: at91: remove useless header file includes
ARM: at91: remove unneeded header file
rtc: at91/Kconfig: remove useless options
ARM: at91/Documentation: add a README for Atmel SoCs
...
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DMA_PAUSE command is used for halting DMA transfer on chosen channel.
It can be useful when we want to safely read residue before terminating
all requests on channel. Otherwise there can be situation when some data
is transferred before channel termination but after reading residue,
which obviously results with data loss. To avoid this situation we can
pause channel, read residue and then terminate all requests.
This scenario is common, for example, in serial port drivers.
Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
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