staging: comedi: comedi_fc.h: begin migration to comedidev.h

"comedi_fc.h" contains a few inline functions used by the `do_cmdtest`
handler functions for comedi subdevices in several low-level comedi
drivers for checking asynchronous command trigger sources and arguments.
They all use the prefix `cfc_check_trigger_arg`.  Copy them over to
"../comedidev.h", but change the `cfc_` prefix to `comedi_`.  Change the
original functions in "comedi_fc.h" into simple wrappers for their
replacements.

Once the drivers have been changed to call the replacement functions,
"comedi_fc.h" can be removed.

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>

1 files changed, 78 insertions, 0 deletions

diff --git a/drivers/staging/comedi/comedidev.h b/drivers/staging/comedi/comedidev.h
index 4720dbcd0b38..dfab5a84b011 100644
--- a/drivers/staging/comedi/comedidev.h
+++ b/drivers/staging/comedi/comedidev.h
@@ -464,6 +464,84 @@ static inline unsigned int comedi_samples_to_bytes(struct comedi_subdevice *s,
 	return nsamples << comedi_sample_shift(s);
 }
 
+/**
+ * comedi_check_trigger_src() - trivially validate a comedi_cmd trigger source
+ * @src: pointer to the trigger source to validate
+ * @flags: bitmask of valid TRIG_* for the trigger
+ *
+ * This is used in "step 1" of the do_cmdtest functions of comedi drivers
+ * to vaildate the comedi_cmd triggers. The mask of the @src against the
+ * @flags allows the userspace comedilib to pass all the comedi_cmd
+ * triggers as TRIG_ANY and get back a bitmask of the valid trigger sources.
+ */
+static inline int comedi_check_trigger_src(unsigned int *src,
+					   unsigned int flags)
+{
+	unsigned int orig_src = *src;
+
+	*src = orig_src & flags;
+	if (*src == TRIG_INVALID || *src != orig_src)
+		return -EINVAL;
+	return 0;
+}
+
+/**
+ * comedi_check_trigger_is_unique() - make sure a trigger source is unique
+ * @src: the trigger source to check
+ */
+static inline int comedi_check_trigger_is_unique(unsigned int src)
+{
+	/* this test is true if more than one _src bit is set */
+	if ((src & (src - 1)) != 0)
+		return -EINVAL;
+	return 0;
+}
+
+/**
+ * comedi_check_trigger_arg_is() - trivially validate a trigger argument
+ * @arg: pointer to the trigger arg to validate
+ * @val: the value the argument should be
+ */
+static inline int comedi_check_trigger_arg_is(unsigned int *arg,
+					      unsigned int val)
+{
+	if (*arg != val) {
+		*arg = val;
+		return -EINVAL;
+	}
+	return 0;
+}
+
+/**
+ * comedi_check_trigger_arg_min() - trivially validate a trigger argument
+ * @arg: pointer to the trigger arg to validate
+ * @val: the minimum value the argument should be
+ */
+static inline int comedi_check_trigger_arg_min(unsigned int *arg,
+					       unsigned int val)
+{
+	if (*arg < val) {
+		*arg = val;
+		return -EINVAL;
+	}
+	return 0;
+}
+
+/**
+ * comedi_check_trigger_arg_max() - trivially validate a trigger argument
+ * @arg: pointer to the trigger arg to validate
+ * @val: the maximum value the argument should be
+ */
+static inline int comedi_check_trigger_arg_max(unsigned int *arg,
+					       unsigned int val)
+{
+	if (*arg > val) {
+		*arg = val;
+		return -EINVAL;
+	}
+	return 0;
+}
+
 /*
  * Must set dev->hw_dev if you wish to dma directly into comedi's buffer.
  * Also useful for retrieving a previously configured hardware device of