On 10/11/16 18:57, Spencer E Olson wrote:
On Thu, 2016-11-10 at 16:29 +0000, Ian Abbott wrote:
On 12/10/16 12:05, Spencer E. Olson wrote:
+ * Base of abstracted NI names.
+ * The first 16 bits of *_arg are reserved for channel selection.
+ * Since we only actually need the first 4 or 5 bits for all register values on
+ * NI select registers anyways, we'll identify all values >= (1<<15) as being 
an
+ * abstracted NI signal/terminal name.
+ * These values are also used/returned by INSN_DEVICE_CONFIG_TEST_ROUTE,
+ * INSN_DEVICE_CONFIG_CONNECT_ROUTE, INSN_DEVICE_CONFIG_DISCONNECT_ROUTE,
+ * and INSN_DEVICE_CONFIG_GET_ROUTES.
+ */
+#define NI_NAMES_BASE  BIT(15)


comedi.h is intended to be moved to uapi/linux/comedi.h, and the BIT(n)
macro cannot be used there.  On the other hand, writing `(1U << 15)`
encourages people to submit patches to change it back to `BIT(15)`. So a
`0x8000u` works well here.

So, out of curiosity, will this mean that the userland comedilib library
might in the future be able to directly reference the kernel version of
comedi.h instead of us needing the keep these in sync manually?

That would mean that comedilib and comedi applications could only be built if the kernel headers include linux/comedi.h, so probably not.

--
-=( Ian Abbott @ MEV Ltd.    E-mail: <abbo...@mev.co.uk> )=-
-=(                          Web: http://www.mev.co.uk/  )=-
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