Re: [PATCH 2/2] device property: add description of fwnode cases

From: Rafael J. Wysocki
Date: Thu Jan 07 2021 - 11:59:33 EST


On Thu, Jan 7, 2021 at 3:11 PM Heikki Krogerus
<heikki.krogerus@xxxxxxxxxxxxxxx> wrote:
>
> On Tue, Jan 05, 2021 at 05:11:46PM +0800, Bard Liao wrote:
> > There are only four valid fwnode cases which are
> > - primary --> secondary --> -ENODEV
> > - primary --> NULL
> > - secondary --> -ENODEV
> > - NULL
> >
> > dev->fwnode should be converted between the 4 cases above no matter
> > how/when set_primary_fwnode() and set_secondary_fwnode() are called.
> > Describe it in the code so people will keep it in mind.
> >
> > Signed-off-by: Bard Liao <yung-chuan.liao@xxxxxxxxxxxxxxx>
>
> Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
>
> > ---
> > drivers/base/core.c | 7 +++++++
> > 1 file changed, 7 insertions(+)
> >
> > diff --git a/drivers/base/core.c b/drivers/base/core.c
> > index 51b9545a050b..17eb14607074 100644
> > --- a/drivers/base/core.c
> > +++ b/drivers/base/core.c
> > @@ -4414,6 +4414,12 @@ static inline bool fwnode_is_primary(struct fwnode_handle *fwnode)
> > *
> > * Set the device's firmware node pointer to @fwnode, but if a secondary
> > * firmware node of the device is present, preserve it.
> > + *
> > + * Valid fwnode cases are:
> > + * - primary --> secondary --> -ENODEV
> > + * - primary --> NULL
> > + * - secondary --> -ENODEV
> > + * - NULL
> > */
> > void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode)
> > {
> > @@ -4432,6 +4438,7 @@ void set_primary_fwnode(struct device *dev, struct fwnode_handle *fwnode)
> > } else {
> > if (fwnode_is_primary(fn)) {
> > dev->fwnode = fn->secondary;
> > + /* Set fn->secondary = NULL to keep fn as a primary fwnode */
> > if (!(parent && fn == parent->fwnode))
> > fn->secondary = NULL;
> > } else {
> > --

Applied (with a minor edit in the new comment) along with the [1/2] as
5.11-rc material, thanks!