* Re: [PATCH 04/19] staging: comedi: adl_pci6208: document the register map of the device
2012-06-28 19:06 ` Dan Carpenter
@ 2012-06-28 19:56 ` Joe Perches
2012-06-28 19:57 ` H Hartley Sweeten
1 sibling, 0 replies; 4+ messages in thread
From: Joe Perches @ 2012-06-28 19:56 UTC (permalink / raw)
To: Dan Carpenter, Andy Whitcroft
Cc: H Hartley Sweeten, Linux Kernel, devel, fmhess, abbotti, gregkh,
Andrew Morton
On Thu, 2012-06-28 at 22:06 +0300, Dan Carpenter wrote:
> On Wed, Jun 27, 2012 at 02:56:43PM -0700, H Hartley Sweeten wrote:
> > Add defines for the register map of the device. These will be
> > used to clarify the code.
[]
> > diff --git a/drivers/staging/comedi/drivers/adl_pci6208.c b/drivers/staging/comedi/drivers/adl_pci6208.c
[]
> > @@ -53,6 +53,18 @@ References:
> > */
> > #include "../comedidev.h"
> >
> > +/*
> > + * PCI-6208/6216-GL register map
> > + */
> > +#define PCI6208_AO_CONTROL(x) (0x00 + (2 * (x)))
> > +#define PCI6208_AO_STATUS 0x00
> > +#define PCI6208_AO_STATUS_DATA_SEND (1 << 0)
> > +#define PCI6208_DIO 0x40
> > +#define PCI6208_DIO_DO_MASK (0x0f)
> > +#define PCI6208_DIO_DO_SHIFT (0)
> > +#define PCI6208_DIO_DI_MASK (0xf0)
> > +#define PCI6208_DIO_DI_SHIFT (4)
[]
> Does checkpatch.pl complain if you leave off these parenthesis?
checkpatch does not complain about those.
I also think parentheses around constants aren't necessary.
I think it's useful around the shifts and necessary
with the arithmetic.
It might be useful to add a (--strict?) test for those
extra parentheses.
Maybe something like:
scripts/checkpatch.pl | 5 +++++
1 files changed, 5 insertions(+), 0 deletions(-)
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index e5bd60f..b6b4d6b 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -2888,6 +2888,11 @@ sub process {
"Whitepspace after \\ makes next lines useless\n" . $herecurr);
}
+ if ($line =~ /^.\s*#\s*define\s+$Ident\s+\(\s*($Constant)\s*\)\s*$/) {
+ CHK("UNNECESSARY_PARENTHESIS",
+ "Unnecessary parenthesis in #define around constant $1\n" . $herecurr);
+ }
+
#warn if <asm/foo.h> is #included and <linux/foo.h> is available (uses RAW line)
if ($tree && $rawline =~ m{^.\s*\#\s*include\s*\<asm\/(.*)\.h\>}) {
my $file = "$1.h";
^ permalink raw reply related [flat|nested] 4+ messages in thread* RE: [PATCH 04/19] staging: comedi: adl_pci6208: document the register map of the device
2012-06-28 19:06 ` Dan Carpenter
2012-06-28 19:56 ` Joe Perches
@ 2012-06-28 19:57 ` H Hartley Sweeten
1 sibling, 0 replies; 4+ messages in thread
From: H Hartley Sweeten @ 2012-06-28 19:57 UTC (permalink / raw)
To: Dan Carpenter; +Cc: Linux Kernel, devel, fmhess, abbotti, gregkh
On Thursday, June 28, 2012 12:06 PM, Dan Carpenter wrote:
> On Wed, Jun 27, 2012 at 02:56:43PM -0700, H Hartley Sweeten wrote:
>> Add defines for the register map of the device. These will be
>> used to clarify the code.
>>
>> Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
>> Cc: Ian Abbott <abbotti@mev.co.uk>
>> Cc: Frank Mori Hess <fmhess@users.sourceforge.net>
>> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>> ---
>> drivers/staging/comedi/drivers/adl_pci6208.c | 12 ++++++++++++
>> 1 file changed, 12 insertions(+)
>>
>> diff --git a/drivers/staging/comedi/drivers/adl_pci6208.c b/drivers/staging/comedi/drivers/adl_pci6208.c
>> index f949d20..b6a8439 100644
>> --- a/drivers/staging/comedi/drivers/adl_pci6208.c
>> +++ b/drivers/staging/comedi/drivers/adl_pci6208.c
>> @@ -53,6 +53,18 @@ References:
>> */
>> #include "../comedidev.h"
>>
>> +/*
>> + * PCI-6208/6216-GL register map
>> + */
>> +#define PCI6208_AO_CONTROL(x) (0x00 + (2 * (x)))
>> +#define PCI6208_AO_STATUS 0x00
>> +#define PCI6208_AO_STATUS_DATA_SEND (1 << 0)
>> +#define PCI6208_DIO 0x40
>> +#define PCI6208_DIO_DO_MASK (0x0f)
>> +#define PCI6208_DIO_DO_SHIFT (0)
>> +#define PCI6208_DIO_DI_MASK (0xf0)
>> +#define PCI6208_DIO_DI_SHIFT (4)
>
> This series is nice and I'm not nacking anything, but really is it
> that useful to say:
> status = inw(dev->iobase + PCI6208_AO_STATUS);
> instead of just?:
> status = inw(dev->iobase);
Either would work.
But the '+ PCI6208_AO_STATUS' used in the function makes it
easily apparent that the 'status' register is being read without
having to go back and see what the assumed '+ 0' register is.
> I'm not sure what the 0x00 in PCI6208_AO_CONTROL represents. Some
> of these are not used like PCI6208_DIO_DI_SHIFT.
Sorry about that. Maybe there should be a comment.
The PCI-6208 has 8 separate "control" registers, one for each DAC output
(the PCI-6216 has 16). They are at offsets 0x00, 0x02, 0x04, ... 0x0e (0x1e for
The PCI-6216). The PCI6208_AO_CONTROL macro is used to calculate the
necessary offset based on the DAC channel. The original code used the
same open-coded logic.
The unused ones can be removed. When I created the patch that added
them I just added everything that might be useful from the manual for
the PCI-6208. I was quite sure what ones would end up un used.
> Does checkpatch.pl complain if you leave off these parenthesis? If
> so I will complain again to the checkpatch.pl people. Extra
> parenthesis are silly and there not used consistently. Only
> PCI6208_AO_CONTROL() and PCI6208_AO_STATUS_DATA_SEND() need
> paranthesis.
No, checkpatch.pl does not complain about the parenthesis either way.
I usually use the parenthesis in the 'bit' defines and not for the 'register'
defines. It helps my brain keep them separate... ;-)
But, they can be removed it needed.
> Again, I'm fine with this patch and the whole series. These are
> just comments.
Thanks for the comments!
Regards,
Hartley
^ permalink raw reply [flat|nested] 4+ messages in thread