Hi Hans,
On Wed, Sep 13, 2017 at 09:57:52AM +0200, Hans Verkuil wrote:
> The subject still has the 'interger' typo.
>
> On 09/12/2017 03:41 PM, Sakari Ailus wrote:
> > v4l2_fwnode_reference_parse_int_prop() will find an fwnode such that under
> > the device's own fwnode, it will follow child fwnodes with the given
> > property -- value pair and return the resulting fwnode.
>
> As suggested before: 'property-value' is easier to read than ' -- '.
Oops. I must have missed some of your comments while making changes.
Apologies for that.
>
> >
> > Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> > ---
> > drivers/media/v4l2-core/v4l2-fwnode.c | 145 ++++++++++++++++++++++++++++++++++
> > 1 file changed, 145 insertions(+)
> >
> > diff --git a/drivers/media/v4l2-core/v4l2-fwnode.c b/drivers/media/v4l2-core/v4l2-fwnode.c
> > index a32473f95be1..a07599a8f647 100644
> > --- a/drivers/media/v4l2-core/v4l2-fwnode.c
> > +++ b/drivers/media/v4l2-core/v4l2-fwnode.c
> > @@ -567,6 +567,151 @@ static int v4l2_fwnode_reference_parse(
> > return ret;
> > }
> >
> > +/*
> > + * v4l2_fwnode_reference_get_int_prop - parse a reference with integer
> > + * arguments
> > + * @dev: struct device pointer
> > + * @notifier: notifier for @dev
> > + * @prop: the name of the property
>
> @index is not documented.
Fixed.
>
> > + * @props: the array of integer property names
> > + * @nprops: the number of integer properties
>
> properties -> property names in @props
Fixed.
>
> > + *
> > + * Find fwnodes referred to by a property @prop, then under that iteratively
> > + * follow each child node which has a property the value matches the integer
>
> "the value" -> "whose value" or "with a value that"
>
> At least, I think that's what you mean here.
>
> How is @props/@nprops used?
>
> > + * argument at an index.
>
> I assume this should be "the @index"?
Um, no. This is the index to the @props array. I'll clarify the
documentation for this function.
>
> > + *
> > + * Return: 0 on success
> > + * -ENOENT if no entries (or the property itself) were found
> > + * -EINVAL if property parsing otherwisefailed
>
> Missing space before "failed"
Fixed.
>
> > + * -ENOMEM if memory allocation failed
> > + */
> > +static struct fwnode_handle *v4l2_fwnode_reference_get_int_prop(
> > + struct fwnode_handle *fwnode, const char *prop, unsigned int index,
> > + const char **props, unsigned int nprops)
> > +{
> > + struct fwnode_reference_args fwnode_args;
> > + unsigned int *args = fwnode_args.args;
> > + struct fwnode_handle *child;
> > + int ret;
> > +
> > + /*
> > + * Obtain remote fwnode as well as the integer arguments.
> > + *
> > + * To-do: handle -ENODATA when "device property: Align return
> > + * codes of acpi_fwnode_get_reference_with_args" is merged.
> > + */
> > + ret = fwnode_property_get_reference_args(fwnode, prop, NULL, nprops,
> > + index, &fwnode_args);
> > + if (ret)
> > + return ERR_PTR(ret == -ENODATA ? -ENOENT : ret);
> > +
> > + /*
> > + * Find a node in the tree under the referred fwnode corresponding the
>
> the -> to the
Fixed.
>
> > + * integer arguments.
> > + */
> > + fwnode = fwnode_args.fwnode;
> > + while (nprops) {
>
> This can be 'while (nprops--) {'.
Changed.
>
> > + u32 val;
> > +
> > + /* Loop over all child nodes under fwnode. */
> > + fwnode_for_each_child_node(fwnode, child) {
> > + if (fwnode_property_read_u32(child, *props, &val))
> > + continue;
> > +
> > + /* Found property, see if its value matches. */
> > + if (val == *args)
> > + break;
> > + }
> > +
> > + fwnode_handle_put(fwnode);
> > +
> > + /* No property found; return an error here. */
> > + if (!child) {
> > + fwnode = ERR_PTR(-ENOENT);
> > + break;
> > + }
> > +
> > + props++;
> > + args++;
> > + fwnode = child;
> > + nprops--;
> > + }
> > +
> > + return fwnode;
> > +}
>
> You really need to add an ACPI example as comment for this source code.
I can copy the relevant portions of the LED flash example, and remove them
once the example is merged to mainline. That example really doesn't belong
here though.
>
> I still don't understand the code. I know you pointed me to an example,
> but I can't remember/find what it was. Either copy the example here or
> point to the file containing the example (copying is best IMHO).
:-)
--
Sakari Ailus
e-mail: sakari.ailus@xxxxxx
