Re: [PATCH v5 1/5] Implement an ioctl to support the USMTMC-USB488 READ_STATUS_BYTE operation.

Andy Shevchenko
2015-11-28T14:57:51Z

On Sat, Nov 28, 2015 at 1:55 PM, Dave Penkler <dpenkler@gmail.com> wrote:
> On Wed, Nov 25, 2015 at 10:38:39PM +0200, Andy Shevchenko wrote:
>> On Wed, Nov 25, 2015 at 11:18 AM, Dave Penkler <dpenkler@gmail.com> wrote:
>> > On Sun, Nov 22, 2015 at 12:32:41PM +0200, Andy Shevchenko wrote:
>> >> On Sun, Nov 22, 2015 at 11:19 AM, Dave Penkler <dpenkler@gmail.com> wrote:
>> >> > On Wed, Nov 18, 2015 at 11:55:27AM +0200, Andy Shevchenko wrote:
>> >> >> On Wed, Nov 18, 2015 at 10:37 AM, Dave Penkler <dpenkler@gmail.com> wrote:

Thank you for an update!

>> >> >> > + switch (status) {
>> >> >> > + case 0: /* SUCCESS */
>> >> >> > + if (data->iin_buffer[0] & 0x80) {
>> >> >> > + /* check for valid STB notification */
>> >> >> > + if ((data->iin_buffer[0] & 0x7f) > 1) {

How can I miss that there are two conditionals in a sequence and
moreover for the same data?!
That might explain the optimization done by compiler.

So, could it be transformed to simple one condition
if (data->iin_buffer[0] > 0x81 /* 129 */) {
?

--
With Best Regards,
Andy Shevchenko