Hi Biju, On Fri, 2019-04-26 at 07:02 +0000, Biju Das wrote: > Hi Chunfeng Yun, > > Thanks for the patch. > > > Subject: [PATCH v4 4/6] usb: roles: add API to get usb_role_switch by node > > > > Add fwnode_usb_role_switch_get() to make easier to get usb_role_switch > > by fwnode which register it. > > It's useful when there is not device_connection registered between two > > drivers and only knows the fwnode which register usb_role_switch. > > > > Signed-off-by: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx> > Tested-by: Biju Das <biju.das@xxxxxxxxxxxxxx> > > --- > > v4 changes: > > 1. use switch_fwnode_match() to find fwnode suggested by Heikki > > 2. this patch now depends on [1] > > > > [1] [v6,08/13] usb: roles: Introduce stubs for the exiting functions in role.h > > https://patchwork.kernel.org/patch/10909971/ > > > > v3 changes: > > 1. use fwnodes instead of node suggested by Andy > > 2. rebuild the API suggested by Heikki > > > > v2 no changes > > --- > > drivers/usb/roles/class.c | 25 +++++++++++++++++++++++++ > > include/linux/usb/role.h | 8 ++++++++ > > 2 files changed, 33 insertions(+) > > > > diff --git a/drivers/usb/roles/class.c b/drivers/usb/roles/class.c index > > f45d8df5cfb8..994fcb979795 100644 > > --- a/drivers/usb/roles/class.c > > +++ b/drivers/usb/roles/class.c > > @@ -12,6 +12,7 @@ > > #include <linux/device.h> > > #include <linux/module.h> > > #include <linux/mutex.h> > > +#include <linux/of.h> > > Is it required? Forgot to remove it after using fwnode instead of node, will remove it in next version Thanks a lot > > > #include <linux/slab.h> > > > > static struct class *role_class; > > @@ -135,6 +136,30 @@ struct usb_role_switch *usb_role_switch_get(struct > > device *dev) } EXPORT_SYMBOL_GPL(usb_role_switch_get); > > > > +/** > > + * fwnode_usb_role_switch_get - Find USB role switch by it's parent > > +fwnode > > + * @fwnode: The fwnode that register USB role switch > > + * > > + * Finds and returns role switch registered by @fwnode. The reference > > +count > > + * for the found switch is incremented. > > + */ > > +struct usb_role_switch * > > +fwnode_usb_role_switch_get(struct fwnode_handle *fwnode) { > > + struct usb_role_switch *sw; > > + struct device *dev; > > + > > + dev = class_find_device(role_class, NULL, fwnode, > > switch_fwnode_match); > > + if (!dev) > > + return ERR_PTR(-EPROBE_DEFER); > > + > > + sw = to_role_switch(dev); > > + WARN_ON(!try_module_get(sw->dev.parent->driver->owner)); > > + > > + return sw; > > +} > > +EXPORT_SYMBOL_GPL(fwnode_usb_role_switch_get); > > + > > /** > > * usb_role_switch_put - Release handle to a switch > > * @sw: USB Role Switch > > diff --git a/include/linux/usb/role.h b/include/linux/usb/role.h index > > da2b9641b877..35d460f9ec40 100644 > > --- a/include/linux/usb/role.h > > +++ b/include/linux/usb/role.h > > @@ -48,6 +48,8 @@ int usb_role_switch_set_role(struct usb_role_switch > > *sw, enum usb_role role); enum usb_role usb_role_switch_get_role(struct > > usb_role_switch *sw); struct usb_role_switch *c(struct > > device *dev); void usb_role_switch_put(struct usb_role_switch *sw); > > +struct usb_role_switch * > > +fwnode_usb_role_switch_get(struct fwnode_handle *fwnode); > > > struct usb_role_switch * > > usb_role_switch_register(struct device *parent, @@ -72,6 +74,12 @@ static > > inline struct usb_role_switch *usb_role_switch_get(struct device *dev) > > > > static inline void usb_role_switch_put(struct usb_role_switch *sw) { } > > > > +static inline struct usb_role_switch * > > +fwnode_usb_role_switch_get(struct fwnode_handle *fwnode) { > > + return ERR_PTR(-ENODEV); > > +} > > + > > > static inline struct usb_role_switch * > > usb_role_switch_register(struct device *parent, > > const struct usb_role_switch_desc *desc) > > -- > > 2.21.0 >