staging: comedi: amplc_pci230: rewrite shared resource handling

Browse source

Some counter channels may be required for AI commands and AO commands.
Depending on how the commands are set up, it may not be possible to run
both at the same time, so we keep some state and code to find out if the
required resources are busy or not.

The existing code is a bit unwieldy - the code for claiming resources
involves two `for` loops for example.  Rewrite it to make it simpler.

The new code just has a bit-mask value for each shared resource (counter
channels), and an array indexed by resource "owners" (AI and AO
commands), so the code for claiming resources now just has a single loop
that checks that none of the other owners have claimed the wanted
resources.

Rename the functions involved, because the old names involving 'put' and
'get' suggested some sort of usage counting.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

...

This commit is contained in:

Ian Abbott 2014-09-01 12:03:54 +01:00 • committed by Greg Kroah-Hartman

parent 4b0ff3dc5e

commit beafb60389

1 changed files with 32 additions and 67 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

115

drivers/staging/comedi/drivers/amplc_pci230.c

View file