Step 1 in moving the IIO core out of staging.
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The below patch fixes some comments and some typos that I have found
while reading drivers/staging/iio/*
Signed-off-by: Justin P. Mattock <justinmattock@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Setup the buffer access functions in the buffer allocate function. There is no
need to let each driver handle this on its own.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
These callbacks are currently used by the individual buffer implementations to
ensure that the request_update callback is not issued while the buffer is in use.
But the core already provides sufficient measures to prevent this from happening
in the first place. So it is safe to remove them.
There is one functional change due to this patch. Since the buffer is no longer
marked as in use when the chrdev is opened, it is now possible to enable the
buffer while it is opened. This did not work before, because mark_param_change
did fail if the buffer was marked as in use.
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Right now we have a mark_param_change callback in the buffer access
functions struct, which should be called whenever the parameters (length,
bytes per datum) of the buffer change. But it is only called when the user
changes the buffer size, not when the bytes per datum change. Additionally each
buffer implementation already keeps track internally whether its parameters
have changed, making the call to mark_param_change after changing the buffer
length redundant. Since each buffer implementation knows best when one of its
parameters has changed just make tracking of this internal and drop the
mark_param_change callback.
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The sw_ring does not properly handle the case where the write pointer already
has wrapped around, the read pointer has not and the remaining buffer space at
the end is enough to fill the read buffer:
+-----------------------------------+
| | |##data##| |
+-----------------------------------+
write_p read_p
In this case the current code will copy all available data to the buffer and
as a result will write beyond the bounds of the buffer and cause a memory
corruption.
To address this issue this patch adds code to calculate the available buffer
space and makes sure that the number of bytes to copy does not exceed this
number. This allows the code which copies the data around to be simplified as
it only has to consider two cases: Read wraps around and read does not wrap
around.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
In all existing cases, the calls are coming from a location where
the indio_dev is already available.
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
No longer needed as we don't have drivers providing sysfs access
to buffered data.
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
There are no known reasons why userspace should want this value.
It can be established from the buffer description anyway.
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
They aren't always ring buffers, so just use buffer for all naming.
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Sorry all, this one is very invasive, though the driver changes are
just trivial interface fixes. Not all done yet.
V2 - bring the sca3000 with us.
V3 - fix ade7758 bugs in conversion.
V4 - add ad5933
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
It seemed like a good idea at the time, it wasn't.
The code with this in place is larger and more complex for
no real gain. Basically we've cleaned up the core around
it so much that this no longer makes sense.
Only really effects the lis3l02dq driver.
Signed-off-by: Jonathan Cameron <jic23@cam.acuk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
1) move a generic helper function out of ring_sw. It applies to other buffers as well.
2) Get rid of a lot of left over function definitions.
3) Move all the access functions into static structures.
4) Introduce and use a static structure for the setup functions, preenable etc.
Some driver conversions thanks to Michael Hennerich (pulled out of patches
that would otherwise sit after this).
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This element has been usused by the core for quite some time. sca3000 set it none the less
until the rewrite in the previous patch (and hence didn't work).
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Given we now only have one device we don't need the extra layer any more.
Hence this patch removes it.
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
part of sca3000 driver temporarily disabled (buffer won't run
anyway). This section is replaced later in this patch set.
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Whilst it is possible to output events to say buffers have passed
a particular level there are no obvious reasons to actually do so.
The upshot of this patch is that buffers will only ever have
one threshold turned on at a time.
For now sca3000 has it's ring buffer effectively disabled.
Fixed later in series.
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Change suggested by Arnd Bergmann, Related patch to remove
pointless (now) dead_offset parameter will have await
proper fix for the sca3000 driver. That depends on
some intermediate patches so may be a little while.
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The current interface is not as adaptable as it should be. Moving
this complexity into the implementations makes it easier to add
new implementations.
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Tested-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
In each case, the containing function is only called from one place, where
a spin lock is held.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@gfp exists@
identifier fn;
position p;
@@
fn(...) {
... when != spin_unlock
when any
GFP_KERNEL@p
... when any
}
@locked@
identifier gfp.fn;
@@
spin_lock(...)
... when != spin_unlock
fn(...)
@depends on locked@
position gfp.p;
@@
- GFP_KERNEL@p
+ GFP_ATOMIC
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Jonathan Cameron <jic23@cam.ac.uk>
Cc: Marek Lindner <lindner_marek@yahoo.de>
Cc: Martyn Welch <martyn.welch@ge.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Some confusion was caused by the ___iio_init_ring_buffer and equivalent
in ring_sw handling both init of spin locks etc and allocation and
of the actual buffer. This resulted in ring->use_lock being held
before it was initialized and actually during the initialization.
Some of the recent cleanups in the spin lock code seem to have triggered
the bug actually causing traceable crashes.
The following patch should fix this but hasn't been extensively tested
as of yet and there may well be some side effects I haven't thought of.
Just wanted to get this out there before anyone else runs into it!
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
This fixes some RT-triggered compile errors and typos.
Signed-off-by: Sven-Thorsten Dietrich <sdietrich@novell.com>
Acked-by: Marek Lindner <lindner_marek@yahoo.de>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Please note this ring buffer implementation is very much a
work in progress (and hence RFC). In it's current form
it is stable and reasonably efficient. There are a couple
of unlikely cases that will lead to more data being lost
that is strictly necessary. The target was for the case
of requiring regular sampling even during user space reads.
All comments welcome.
The intention is to make this only one of several
implementations with run time selection. For now there
is only one, so it is hard coded into the drivers using it.
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>