From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chunfeng Yun Subject: [v3 PATCH 4/6] usb: roles: add API to get usb_role_switch by node Date: Wed, 3 Apr 2019 10:09:12 +0800 Message-ID: <1554257354-7440-5-git-send-email-chunfeng.yun@mediatek.com> References: <1554257354-7440-1-git-send-email-chunfeng.yun@mediatek.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <1554257354-7440-1-git-send-email-chunfeng.yun@mediatek.com> Sender: linux-kernel-owner@vger.kernel.org To: Rob Herring , Greg Kroah-Hartman , Heikki Krogerus Cc: Mark Rutland , Chunfeng Yun , Matthias Brugger , Adam Thomson , Li Jun , Badhri Jagan Sridharan , Hans de Goede , Andy Shevchenko , Min Guo , Alan Stern , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org List-Id: devicetree@vger.kernel.org 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 --- 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 | 31 +++++++++++++++++++++++++++++++ include/linux/usb/role.h | 2 ++ 2 files changed, 33 insertions(+) diff --git a/drivers/usb/roles/class.c b/drivers/usb/roles/class.c index f45d8df5cfb8..5ecb57f8960b 100644 --- a/drivers/usb/roles/class.c +++ b/drivers/usb/roles/class.c @@ -12,6 +12,7 @@ #include #include #include +#include #include static struct class *role_class; @@ -135,6 +136,36 @@ struct usb_role_switch *usb_role_switch_get(struct device *dev) } EXPORT_SYMBOL_GPL(usb_role_switch_get); +static int __switch_match_fwnode(struct device *dev, const void *fwnode) +{ + return dev_fwnode(dev->parent) == (const struct fwnode_handle *)fwnode; +} + +/** + * 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_match_fwnode); + 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 c05ffa6abda9..d21cd55d9e45 100644 --- a/include/linux/usb/role.h +++ b/include/linux/usb/role.h @@ -46,6 +46,8 @@ 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 *usb_role_switch_get(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, -- 2.20.1