| Message ID | 1552025622-15582-4-git-send-email-chunfeng.yun@mediatek.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | add USB Type-B connector driver | expand |
On Fri, Mar 8, 2019 at 8:14 AM Chunfeng Yun <chunfeng.yun@mediatek.com> wrote: > > Add usb_role_switch_get_by_node() to make easier to get > usb_role_switch by node which register it. > It's useful when there is not device_connection registered > between two drivers and only knows the node which register > usb_role_switch. > +static int __switch_match_node(struct device *dev, const void *node) > +{ > + return dev->parent->of_node == (const struct device_node *)node; > +} Hmm... Shouldn't be slightly better to compare fwnode instead?
Hi, On Fri, 2019-03-08 at 08:52 +0200, Andy Shevchenko wrote: > On Fri, Mar 8, 2019 at 8:14 AM Chunfeng Yun <chunfeng.yun@mediatek.com> wrote: > > > > Add usb_role_switch_get_by_node() to make easier to get > > usb_role_switch by node which register it. > > It's useful when there is not device_connection registered > > between two drivers and only knows the node which register > > usb_role_switch. > > > +static int __switch_match_node(struct device *dev, const void *node) > > +{ > > + return dev->parent->of_node == (const struct device_node *)node; > > +} > > Hmm... Shouldn't be slightly better to compare fwnode instead? > Using fwnode is indeed suitable for more cases, I find that there are many functions named xx_by_node using node, but not fwnode, is there any rules about choice between device_node and fwnode_handle? Thanks
diff --git a/drivers/usb/roles/class.c b/drivers/usb/roles/class.c index 99116af07f1d..284b19856dc4 100644 --- a/drivers/usb/roles/class.c +++ b/drivers/usb/roles/class.c @@ -11,6 +11,7 @@ #include <linux/device.h> #include <linux/module.h> #include <linux/mutex.h> +#include <linux/of.h> #include <linux/slab.h> static struct class *role_class; @@ -121,6 +122,35 @@ struct usb_role_switch *usb_role_switch_get(struct device *dev) } EXPORT_SYMBOL_GPL(usb_role_switch_get); +static int __switch_match_node(struct device *dev, const void *node) +{ + return dev->parent->of_node == (const struct device_node *)node; +} + +/** + * usb_role_switch_get_by_node - Find USB role switch by it's parent node + * @node: The node that register USB role switch + * + * Finds and returns role switch registered by @node. The reference count + * for the found switch is incremented. + */ +struct usb_role_switch *usb_role_switch_get_by_node(struct device_node *node) +{ + struct usb_role_switch *sw; + struct device *dev; + + dev = class_find_device(role_class, NULL, node, + __switch_match_node); + 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(usb_role_switch_get_by_node); + /** * 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 edc51be4a77c..056498b83dee 100644 --- a/include/linux/usb/role.h +++ b/include/linux/usb/role.h @@ -42,6 +42,7 @@ struct usb_role_switch_desc { 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 *usb_role_switch_get_by_node(struct device_node *node); struct usb_role_switch *usb_role_switch_get(struct device *dev); void usb_role_switch_put(struct usb_role_switch *sw);
Add usb_role_switch_get_by_node() to make easier to get usb_role_switch by node which register it. It's useful when there is not device_connection registered between two drivers and only knows the node which register usb_role_switch. Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com> --- drivers/usb/roles/class.c | 30 ++++++++++++++++++++++++++++++ include/linux/usb/role.h | 1 + 2 files changed, 31 insertions(+)