The driver already won't initialize a channel with a circular buffer;
the check in pl08x_prep_channel_resources() sees to that. Remove
circular buffer support for the time being.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The tasklet always is initialized with a non-NULL data argument. It
is not possible for it to be called with a NULL data argument (unless
something is very wrong in the tasklet code - in which case lots of
stuff will break). Therefore, as plchan can never be NULL, remove
this unnecessary BUG check.
In pl08x_tasklet(), we've already dereferenced plchan->at, so it can't
be NULL here. Remove this unnecessary BUG check.
pl08x_fill_llis_for_desc() and pl08x_free_txd() are always called with
a non-NULL txd argument - either as a consequence of the code paths or
as a result of other checks already in place. We don't need to repeat
the non-NULL check in these functions.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
We don't need to include linux/pci.h as we aren't a PCI driver. We
aren't doing any processor specific functions, so asm/processor.h is
not required. asm/cacheflush.h shouldn't be used, we have the DMA API
for this. DMA interfaces aren't required as we're only implementing
the dmaengine API and not a platform-private DMA API.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
A driver which emits both decimal and hex numbers in its printk
creates confusion as to what is what. Prefix hex numbers with 0x.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Include the revision number of the PL08x primecell in the boot-time
printk to allow proper identification of the peripheral. Reformat
the announcement printk format reflect what we do for other primecell
drivers - generally "PLXXX revX at 0xNNNNNNNN irq X".
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Explain the two flow control methods which the PL08x implements, along
with the problem which peripheral flow control presents. This helps
people understand why we are unable to use these DMA controllers with
(eg) the MMCI.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
drivers/dma/amba-pl08x.c:1895:40: warning: Unknown escape '%'
drivers/dma/amba-pl08x.c:1903:40: warning: Unknown escape '%'
drivers/dma/amba-pl08x.c:513:6: warning: symbol 'pl08x_choose_master_bus' was not declared. Should it be static?
drivers/dma/amba-pl08x.c:604:5: warning: symbol 'pl08x_fill_llis_for_desc' was not declared. Should it be static?
drivers/dma/amba-pl08x.c:1442:32: warning: symbol 'pl08x_prep_slave_sg' was not declared. Should it be static?
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Trying to disable a tasklet while holding a spinlock which the tasklet
will take is a recipe for deadlock - tasklet_disable() will wait for the
tasklet to finish running, which it will never do. In any case, there
is not a corresponding tasklet_enable(), so once the tasklet is disabled,
it will never run again until reboot.
It's safe to just remove the tasklet_disable() as we remove all current
and pending descriptors before releasing this spinlock. This means that
the tasklet will find no remaining work if it subsequently runs.
The only remaining issue is that the callback for an already submitted
txd may be in progress, or even called after terminate_all() returns.
There's not much that can be done about that as waiting for the callback
to complete before returning will also lead to deadlocks.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
pl08x_issue_pending() returns with the spinlock locked and interrupts
disabled if the channel is waiting for a physical DMA to become free.
This is wrong - especially as pl08x_issue_pending() is an API function
as it leads to deadlocks. Fix it to always return with the spinlock
unlocked.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
If we fail to allocate the LLI, the prep_* function will return NULL.
However, the TXD we allocated will not be placed on any list, nor
will it be freed - we'll just drop all references to it. Make sure
we free it rather than leaking TXDs.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Tasklets are run from an interruptible context. The slave DMA functions
can be called from within IRQ handlers. Taking the spinlock without
disabling interrupts allows an interrupt handler to run, which may try
to take the spinlock again, resulting in deadlock. Fix this by using
the irqsave spinlocks.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The last_issued variable uses an atomic type, which is only
incremented inside a protected region, and then read. Everywhere else
only reads the value, so it isn't using atomic_t correctly, and it
doesn't even need to. Moreover, the DMA engine code provides us with
a variable for this already - chan.cookie. Use chan.cookie instead.
Also, avoid negative dma_cookie_t values - negative returns from
tx_submit() mean failure, yet in reality we always succeed. Restart
from cookie 1, just like other DMA engine drivers do.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
If maxburst was passed in as zero, we would overflow the burst_sizes[]
array. Fix this by checking for this condition, and defaulting to
single transfer 'bursts'.
Improve the readability of the loop using a for() loop rather than
a while() loop with the iterator initialized far from the loop.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Correct mis-spellings in comments and printk strings.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Product codenames are OK, but once an actual product name is available,
it should be referenced as well.
http://ark.intel.com/chipset.aspx?familyID=52499
Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx: (48 commits)
DMAENGINE: move COH901318 to arch_initcall
dma: imx-dma: fix signedness bug
dma/timberdale: simplify conditional
ste_dma40: remove channel_type
ste_dma40: remove enum for endianess
ste_dma40: remove TIM_FOR_LINK option
ste_dma40: move mode_opt to separate config
ste_dma40: move channel mode to a separate field
ste_dma40: move priority to separate field
ste_dma40: add variable to indicate valid dma_cfg
async_tx: make async_tx channel switching opt-in
move async raid6 test to lib/Kconfig.debug
dmaengine: Add Freescale i.MX1/21/27 DMA driver
intel_mid_dma: change the slave interface
intel_mid_dma: fix the WARN_ONs
intel_mid_dma: Add sg list support to DMA driver
intel_mid_dma: Allow DMAC2 to share interrupt
intel_mid_dma: Allow IRQ sharing
intel_mid_dma: Add runtime PM support
DMAENGINE: define a dummy filter function for ste_dma40
...
NULL-terminating pci_device_id in pch_dma.c and scx200_acb.c
for appying MODULE_DEVICE_TABLE (to publish modalias-es).
Signed-off-by: Dzianis Kahanovich <mahatma@eu.by>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
After moving the PL022 driver to subsys_initcall() due to the need
of having stuff like regulators on the other end of the SPI link,
I noticed that the COH901318 DMA engine will get probed before
the DMA engine, so move it to an arch_initcall().
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
mxdmac->channel was unsigned, so check (imxdmac->channel < 0) for
failed imx_dma_request_by_prio() made no sence. Explicitly check
signed values.
Also, fix uninitialzed use of ret.
Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl:
vfs: make no_llseek the default
vfs: don't use BKL in default_llseek
llseek: automatically add .llseek fop
libfs: use generic_file_llseek for simple_attr
mac80211: disallow seeks in minstrel debug code
lirc: make chardev nonseekable
viotape: use noop_llseek
raw: use explicit llseek file operations
ibmasmfs: use generic_file_llseek
spufs: use llseek in all file operations
arm/omap: use generic_file_llseek in iommu_debug
lkdtm: use generic_file_llseek in debugfs
net/wireless: use generic_file_llseek in debugfs
drm: use noop_llseek
Simplify: ((a && b) || (!a && !b)) => (a == b)
Signed-off-by: Nicolas Kaiser <nikai@nikai.net>
Acked-by: Jack Stone <jwjstone@fastmail.fm>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
A bool will suffice. The default is little endian.
Acked-by: Jonas Aaberg <jonas.aberg@stericsson.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Defaults are "basic mode" for physical channels, and "logical source
logical destination" for logical channels.
Acked-by: Jonas Aaberg <jonas.aberg@stericsson.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
And keep it logical by default.
Acked-by: Jonas Aaberg <jonas.aberg@stericsson.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
And keep it low priority by default.
Acked-by: Jonas Aaberg <jonas.aberg@stericsson.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Since we want to reduce the amount of required channel
configuration and remove channel_type, don't depend on it
to indicate whether the configuration is valid.
Acked-by: Jonas Aaberg <jonas.aberg@stericsson.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.
The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.
New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time. Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.
The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.
Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.
Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.
===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
// but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{
<+...
nonseekable_open(...)
...+>
}
@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{
<+...
(
nonseekable_open(...)
|
nested_open(...)
)
...+>
}
@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}
@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}
@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}
@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}
@ fops0 @
identifier fops;
@@
struct file_operations fops = {
...
};
@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
.llseek = llseek_f,
...
};
@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
.read = read_f,
...
};
@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
.write = write_f,
...
};
@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
.open = open_f,
...
};
// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
... .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};
@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
... .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};
// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
... .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};
// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};
// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};
@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+ .llseek = default_llseek, /* write accesses f_pos */
};
// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////
@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
.write = write_f,
.read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};
@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};
@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};
@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>
Commit 0793448 "DMAENGINE: generic channel status v2" changed the interface for
how dma channel progress is retrieved. It inadvertently exported an internal
helper function ioat_tx_status() instead of ioat_dma_tx_status(). The latter
polls the hardware to get the latest completion state, while the helper just
evaluates the current state without touching hardware. The effect is that we
end up waiting for completion timeouts or descriptor allocation errors before
the completion state is updated.
iperf (before fix):
[SUM] 0.0-41.3 sec 364 MBytes 73.9 Mbits/sec
iperf (after fix):
[SUM] 0.0- 4.5 sec 499 MBytes 940 Mbits/sec
This is a regression starting with 2.6.35.
Cc: <stable@kernel.org>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Jesse Brandeburg <jesse.brandeburg@intel.com>
Cc: Linus Walleij <linus.walleij@stericsson.com>
Cc: Maciej Sosnowski <maciej.sosnowski@intel.com>
Reported-by: Richard Scobie <richard@sauce.co.nz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The majority of drivers in drivers/dma/ will never establish cross
channel operation chains and do not need the extra overhead in struct
dma_async_tx_descriptor. Make channel switching opt-in by default.
Cc: Anatolij Gustschin <agust@denx.de>
Cc: Ira Snyder <iws@ovro.caltech.edu>
Cc: Linus Walleij <linus.walleij@stericsson.com>
Cc: Saeed Bishara <saeed@marvell.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This driver is currently implemented as a user to the old i.MX
DMA API. This allows us to convert each user of the old API to
the dmaengine API one by one. Once this is done the old DMA
driver can be merged into the i.MX dmaengine driver.
V2: remove some debug leftovers and unused variables
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In 2.6.36 kernel, dma slave control command was introduced,
this patch changes the intel-mid-dma driver to this
new kernel slave interface
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Moved the WARN_ON to BUG_ON, as WARN_ON if hit,
can cause null pointer derefrences
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
For a very high speed DMA various periphral devices need
scatter-gather list support. The DMA hardware support link list items.
This list can be circular also (adding new flag DMA_PREP_CIRCULAR_LIST)
Right now this flag is in driver header and should be moved to
dmaengine header file eventually
Signed-off-by: Ramesh Babu K V <ramesh.b.k.v@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Allow DMAC2 to share interrupt since exclusive interrupt line
for mrst DMAC2 is not provided on other platforms.
Signed-off-by: Yong Wang <yong.y.wang@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
intel_mid_dma driver allows interrupt sharing. Thus it needs
to check whether IRQ source is the DMA controller and return
the appropriate IRQ return.
Signed-off-by: Yong Wang <yong.y.wang@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This patch adds runtime PM support in this dma driver
for 4 PCI Controllers
Whenever the driver is idle (no channels grabbed), it
can go to low power state
It also adds the PCI suspend and resume support
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Remove obsolete pre_transfer hook in stedma40_chan_cfg. The
intent of this hook is merely to handle burst size
compensation for ux500 variant MMCI. Remove obsolete stedma40_set_psize
since it is only called from pre_transfer. DMAEngine device_control
replaces the functionality of stedma40_set_psize.
Signed-off-by: Per Forlin <per.forlin@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Set burst for physical or logical channels respectively.
Convert the values in dma_cfg to dma reg bits
for physical or logical channels.
Signed-off-by: Per Forlin <per.forlin@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Fix some leaks of allocated descriptors in error paths.
Acked-by: Jonas Aaberg <jonas.aberg@stericsson.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Fix desc_get to alloc a descriptor from the cache if the ones in the
list are waiting for the ack. Also, memzero the descriptor when
allocated from the list to ensure all fields are cleared.
Acked-by: Jonas Aaberg <jonas.aberg@stericsson.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
clk_get returns an ERR_PTR.
Acked-by: Jonas Aaberg <jonas.aberg@stericsson.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The value in the array, not the index, specifies the channel to be
disabled.
Acked-by: Jonas Aaberg <jonas.aberg@stericsson.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Now that the DMAEngine API has support for scatterlist to scatterlist
copy, implement support for the STE DMA40 DMA controller.
Cc: Linus Walleij <linus.ml.walleij@gmail.com>
Acked-by: Per Fridén <per.friden@stericsson.com>
Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Now that the generic DMAEngine API has support for scatterlist to
scatterlist copying, the device_prep_slave_sg() portion of the
DMA_SLAVE API is no longer necessary and has been removed.
However, the device_control() portion of the DMA_SLAVE API is still
useful to control device specific parameters, such as externally
controlled DMA transfers and maximum burst length.
A special dma_ctrl_cmd has been added to enable externally controlled
DMA transfers. This is currently specific to the Freescale DMA
controller, but can easily be made generic when another user is found.
Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Now that the DMAEngine API has support for scatterlist to scatterlist
copy, implement support for the Freescale DMA controller.
Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This adds support for scatterlist to scatterlist DMA transfers. A
similar interface is exposed by the fsldma driver (through the DMA_SLAVE
API) and by the ste_dma40 driver (through an exported function).
This patch paves the way for making this type of copy operation a part
of the generic DMAEngine API. Futher patches will add support in
individual drivers.
Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This patch adds support for the Freescale i.MX SDMA engine.
The SDMA engine is a scatter/gather DMA engine which is implemented
as a seperate coprocessor. SDMA needs its own firmware which is
requested using the standard request_firmware mechanism. The firmware
has different entry points for each peripheral type, so drivers
have to pass the peripheral type to the DMA engine which in turn
picks the correct firmware entry point from a table contained in
the firmware image itself.
The original Freescale code also supports support for transfering
data to the internal SRAM which needs different entry points to
the firmware. Support for this is currently not implemented. Also,
support for the ASRC (asymmetric sample rate converter) is skipped.
I took a very simple approach to implement dmaengine support. Only
a single descriptor is statically assigned to a each channel. This
means that transfers can't be queued up but only a single transfer
is in progress. This simplifies implementation a lot and is sufficient
for the usual device/memory transfers.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Linus Walleij <linus.ml.walleij@gmail.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Cyclic transfers are useful for audio where a single buffer divided
in periods has to be transfered endlessly until stopped. After being
prepared the transfer is started using the dma_async_descriptor->tx_submit
function. dma_async_descriptor->callback is called after each period.
The transfer is stopped using the DMA_TERMINATE_ALL callback.
While being used for cyclic transfers the channel cannot be used
for other transfer types.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
