There exist systems with multiple DMA controllers with different
capabilities. For example, on some sh-mobile / rmobile systems there are
DMA controllers, whose channels can be configured to be used with
SD- and MMC-host controllers, serial ports etc. Besides there are also
DMA controllers, that can only be used for one special function, e.g.,
for USB. In such cases the DMA client filter function can just choose
to specify to the DMA driver, which channel it needs. Then the
.device_alloc_chan_resources() method of the DMA driver will check,
whether it can provide that dunction. If not, it will fail and the loop
in __dma_request_channel() will continue to the next DMA device, until
it finds a suitable one. This works fine with just one minor glitch:
the kernel logs error messages like

dmaengine: failed to get <channel name>: (-<error code>)

after each such non-critical failure. This patch lowers priority of
this message to the debug level.
Reported-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Tested-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Tested-by: NMagnus Damm <damm@opensource.se>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

The symbol 'ep93xx_dma_prep_dma_memcpy' is only used in this driver
and should be marked static.
Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Mika Westerberg <mika.westerberg@iki.fi>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Acked-by: NMika Westerberg <mika.westerberg@iki.fi>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

The ep93xx DMA controller has 10 independent memory to peripheral (M2P)
channels, and 2 dedicated memory to memory (M2M) channels. M2M channels can
also be used by SPI and IDE to perform DMA transfers to/from their memory
mapped FIFOs.

This driver supports both M2P and M2M channels with DMA_SLAVE, DMA_CYCLIC and
DMA_MEMCPY (M2M only) capabilities.
Signed-off-by: NMika Westerberg <mika.westerberg@iki.fi>
Signed-off-by: NRyan Mallon <rmallon@gmail.com>
Acked-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: NVinod Koul <vinod.koul@intel.com>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Anatolij Gustschin <agust@denx.de>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

The ep93xx DMA controller has 10 independent memory to peripheral (M2P)
channels, and 2 dedicated memory to memory (M2M) channels. M2M channels can
also be used by SPI and IDE to perform DMA transfers to/from their memory
mapped FIFOs.

This driver supports both M2P and M2M channels with DMA_SLAVE, DMA_CYCLIC and
DMA_MEMCPY (M2M only) capabilities.
Signed-off-by: NMika Westerberg <mika.westerberg@iki.fi>
Signed-off-by: NRyan Mallon <rmallon@gmail.com>
Acked-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: NVinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

A recent patch has introduced a regression, where repeating a memcpy
DMA test with shdma module unloading between them skips the DMA channel
configuration. Fix this regression by always configuring the channel
during its allocation.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

ISSUE: In case PCH_DMA with I2S communications with ch8~ch11, sometimes I2S data
is not send correctly.
CAUSE: The following patch I submitted before was not enough modification for
supporting DMA ch8~ch11. The modification for status register of ch8~11 was not
enough.

pch_dma: Support I2S for ML7213 IOH
author	Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
	Mon, 9 May 2011 07:09:38 +0000 (16:09 +0900)
committer	Vinod Koul <vinod.koul@intel.com>
	Mon, 9 May 2011 11:42:23 +0000 (16:42 +0530)
commit	194f5f27
tree	c9d4903ea02b18939a4f390956a48be1a3734517
parent	60092d0b

This patch fixes the issue.
We can confirm PCH_DMA with I2S communications with ch8~ch11 works well.
Signed-off-by: NTomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

The runtime PM changes introduce sh_dmae_rst() wrapping via the
runtime_resume helper, depending on dev_get_drvdata() to fetch the
platform data needed for the DMAOR initialization default at a time
where drvdata hasn't yet been established by the probe path, resulting
in general probe misery:

        Unable to handle kernel NULL pointer dereference at virtual address 000000c4
        pc = 8025adee
        *pde = 00000000
        Oops: 0000 [#1]
        Modules linked in:

        Pid : 1, Comm:           swapper
        CPU : 0                  Not tainted  (3.0.0-rc1-00012-g9436b4ab-dirty #1456)

        PC is at sh_dmae_rst+0x28/0x86
        PR is at sh_dmae_rst+0x22/0x86
        PC  : 8025adee SP  : 9e803d10 SR  : 400080f1 TEA : 000000c4
        R0  : 000000c4 R1  : 0000fff8 R2  : 00000000 R3  : 00000040
        R4  : 000000f0 R5  : 00000000 R6  : 00000000 R7  : 804f184c
        R8  : 00000000 R9  : 804dd0e8 R10 : 80283204 R11 : ffffffda
        R12 : 000000a0 R13 : 804dd18c R14 : 9e803d10
        MACH: 00000000 MACL: 00008f20 GBR : 00000000 PR  : 8025ade8

        Call trace:
        [<8025ae70>] sh_dmae_runtime_resume+0x24/0x34
        [<80283238>] pm_generic_runtime_resume+0x34/0x3c
        [<80283370>] rpm_callback+0x4a/0x7e
        [<80283efc>] rpm_resume+0x240/0x384
        [<80283f54>] rpm_resume+0x298/0x384
        [<8028428c>] __pm_runtime_resume+0x44/0x7c
        [<8038a358>] __ioremap_caller+0x0/0xec
        [<80284296>] __pm_runtime_resume+0x4e/0x7c
        [<8038a358>] __ioremap_caller+0x0/0xec
        [<80666254>] sh_dmae_probe+0x180/0x6a0
        [<802803ae>] platform_drv_probe+0x26/0x2e

Fix up the ordering accordingly.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

For certain system configurations a 5 usec udelay before checking I/OAT DMA
channel status is sometimes not sufficient, resulting in a false failure
status and unnecessary freeing of channel resources.  Conversely, for many
configurations 5 usec is longer than necessary.

Loop for up to 20 usec waiting for successful status before failing.
Signed-off-by: NDimitri Sivanich <sivanich@sgi.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Signed-off-by: NVinod Koul <vinod.koul@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

With the addition of a device platform mfd_cell pointer, MFD drivers
can go back to passing platform data back to their sub drivers.
This allows for an mfd_cell->mfd_data removal and thus keep the
sub drivers MFD agnostic. This is mostly needed for non MFD aware
sub drivers.
Acked-by: NRichard Röjfors <richard.rojfors@pelagicore.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Nobody is currently maintaining dw_dmac. We are using dw_dmac for SPEAr13xx and
are currently maintaining it. After discussing with Vinod, sending this patch to
update maintainer-ship of dw_dmac.
Signed-off-by: NViresh Kumar <viresh.kumar@st.com>
Acked-by: NHavard Skinnemoen <hskinnemoen@gmail.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Update SH_DMAC_MAX_CHANNELS to support the 20 DMA
channels included in the sh73a0 SY-DMAC hardware.
Signed-off-by: NMagnus Damm <damm@opensource.se>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Fix the shdma.c handing of SH_DMAC_MAX_CHANNELS
to avoid overwriting the chan_irq[] and chan_flag[]
arrays in the case of pdata->channel_num is larger
than SH_DMAC_MAX_CHANNELS.

With this patch applied up to SH_DMAC_MAX_CHANNELS
will be used by the shdma.c driver. If more channels
are available in the platform data the user will
be notified on the console.
Signed-off-by: NMagnus Damm <damm@opensource.se>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This patch makes the shdma.c driver allow slave operation
on DMA hardware mapped with a single I/O-memory window.

The dmae_set_dmars() function is adjusted to use the
first memory window in case of a missing DMARS window.

At probe() time the code is updated to enable DMA_SLAVE
only if slave information is passed with the platform data.
Signed-off-by: NMagnus Damm <damm@opensource.se>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

After discovering that wide use of prefetch on modern CPUs
could be a net loss instead of a win, net drivers which were
relying on the implicit inclusion of prefetch.h via the list
headers showed up in the resulting cleanup fallout.  Give
them an explicit include via the following $0.02 script.

 =========================================
 #!/bin/bash
 MANUAL=""
 for i in `git grep -l 'prefetch(.*)' .` ; do
 	grep -q '<linux/prefetch.h>' $i
 	if [ $? = 0 ] ; then
 		continue
 	fi

 	(	echo '?^#include <linux/?a'
 		echo '#include <linux/prefetch.h>'
 		echo .
 		echo w
 		echo q
 	) | ed -s $i > /dev/null 2>&1
 	if [ $? != 0 ]; then
 		echo $i needs manual fixup
 		MANUAL="$i $MANUAL"
 	fi
 done
 echo ------------------- 8\<----------------------
 echo vi $MANUAL
 =========================================
Signed-off-by: NPaul <paul.gortmaker@windriver.com>
[ Fixed up some incorrect #include placements, and added some
  non-network drivers and the fib_trie.c case    - Linus ]
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

List elements, deleted using list_del_rcu(), cannot be freed without
synchronising RCU. Further, the spinlock, used to protect the RCU
writer, is called in process context, so, we don't have to save flags.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This patch extends and fixes runtime power management in the shdma
driver to support powering down the DMA controller and adds support
for system-level suspend and resume.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Close multiple theoretical races, especially the one in
.device_free_chan_resources().
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Move the dmaengine subsystem up early in the drivers Makefile so
DMA is made available early to all drivers, just like e.g.
regulators. Now even regulators can use DMA on the same initlevel.
As a result we can bump the ste_dma40 and coh901318 dmaengine
drivers down one initlevel to subsys_init().
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Haavard's e-mail address at Atmel is no longer valid.
Signed-off-by: NJean Delvare <khali@linux-fr.org>
Acked-by: NHavard Skinnemoen <hskinnemoen@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Some peripherals like amba-pl011 needs pause to be implemented in DMA controller
drivers. This also returns correct status from dwc_tx_status() in case chan is
paused.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NViresh Kumar <viresh.kumar@st.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

dmaengine routines can be called from interrupt context and with interrupts
disabled.  Whereas spin_unlock_bh can't be called from such contexts. So this
patch converts all spin_*_bh routines to irqsave variants.

Also, spin_lock() used in tasklet is converted to irqsave variants, as tasklet
can be interrupted, and dma requests from such interruptions may also call
spin_lock.

Now, submission from callbacks are permitted as per dmaengine framework. So we
shouldn't hold any locks while calling callbacks. As locks were taken by parent
routines, so releasing them before calling callbacks doesn't look clean enough.
So, locks are taken inside all routine now, whereever they are required. And
dwc_descriptor_complete is always called without taking locks.
Signed-off-by: NViresh Kumar <viresh.kumar@st.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

If len passed in sg for slave_sg transfers is greater than DWC_MAX_COUNT, then
driver programmes controller incorrectly.  This patch adds code to handle this
situation by allocation more than one desc for same sg.
Signed-off-by: NViresh Kumar <viresh.kumar@st.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

If transfer status is !=DMA_SUCCESS, return total transfer len as residue,
instead of zero.
Signed-off-by: NViresh Kumar <viresh.kumar@st.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

If dmaengine_terminate_all() is called for dma channel, then it doesn't make
much sense to call registered callback routine. While in case of success or
failure it must be called.
Signed-off-by: NViresh Kumar <viresh.kumar@st.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

With the addition of the "pause" feature, an active wait was introduced
to check the "FIFO empty" event. This event was not always happening and
a timout contition was needed.
But, in some cases, this event depend on the peripheral connected to the
channel that is paused: FIFO becomes empty if the peripheral consumes data.
The timeout is pretty difficult to evaluate. Moreover, this check is not
needed.
In conclusion, it seems sensible to entirely remove the checking of
"FIFO empty" status when pausing.
Signed-off-by: NNicolas Ferre <nicolas.ferre@atmel.com>
[commit msg edited for grammer]
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Signed-off-by: NTomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Support new device OKI SEMICONDUCTOR ML7223 IOH(Input/Output Hub).
The ML7223 IOH is for MP(Media Phone) use.
The ML7223 is companion chip for Intel Atom E6xx series.
The ML7223 is completely compatible for Intel EG20T PCH.
Signed-off-by: NTomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Support I2S device for ML7213 IOH
Signed-off-by: NTomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Currently, Direct-Start mode(*) is enabled.
Our IOH's devices must not use this mode.
This causes unexpected behavior.
This patch deletes Direct-Start setting.
(*) This mode is used in order for CPU to generate the DMA request.
Signed-off-by: NTomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Fix checkpatch warnings.
Signed-off-by: NTomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Currently, even-channel number is set as tx direction and odd is set as rx.
However, though video-in uses ch6, the direction is not tx but rx.
This patch sets video-in's DMA direction correctly.
Signed-off-by: NTomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

A little function helps to chain descriptors:
it is already used in cyclic dma operations, now use it in memcpy and slave_sg
preparation functions.
Signed-off-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

Pause and resume controls are useful for audio devices. This also returns
correct status from atc_tx_status() in case chan is paused.

Idea from dw_dmac patch by Linus Walleij.
Signed-off-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

If transfer status is !=DMA_SUCCESS, return total transfer len as residue,
instead of zero.

Idea from dw_dmac patch by Viresh Kumar.
Signed-off-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

The compiler nowadays moans about possibly non-assigned variable.
Fix this by default-assigning 0.
Signed-off-by: NPhilippe Langlais <philippe.langlais@linaro.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

DMA controller has two AHB interfaces on the SOC internal
matrix.
It is more efficient to specialize each interface as the
access to memory can introduce latencies that are not compatible
with peripheral accesses requirements.
Signed-off-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>

There is no need to test if channel is enabled in tasklet:
- in error path, channel is disabled in interrupt routine
- in normal path, this test is performed in sub functions to report
a misuse of the engine.
Signed-off-by: NNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>