[v3,4/6] usb: roles: add API to get usb_role_switch by node
diff mbox series

Message ID 1554257354-7440-5-git-send-email-chunfeng.yun@mediatek.com
State Superseded
Headers show
Series
  • add USB Type-B GPIO connector driver
Related show

Commit Message

Chunfeng Yun April 3, 2019, 2:09 a.m. UTC
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@mediatek.com>
---
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(+)

Comments

Heikki Krogerus April 10, 2019, 10:22 a.m. UTC | #1
On Wed, Apr 03, 2019 at 10:09:12AM +0800, Chunfeng Yun wrote:
> 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@mediatek.com>
> ---
> 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 <linux/device.h>
>  #include <linux/module.h>
>  #include <linux/mutex.h>
> +#include <linux/of.h>
>  #include <linux/slab.h>
>  
>  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;
> +}

I don't think this is actually needed. Why not just assign the
parent's fwnode for the mux as well?

I'll add an example to the patch 6/6 in this series.

> +/**
> + * 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);

So here you can then reuse switch_fwnode_match():

	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 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

thanks,
Chunfeng Yun April 11, 2019, 3:11 a.m. UTC | #2
On Wed, 2019-04-10 at 13:22 +0300, Heikki Krogerus wrote:
> On Wed, Apr 03, 2019 at 10:09:12AM +0800, Chunfeng Yun wrote:
> > 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@mediatek.com>
> > ---
> > 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 <linux/device.h>
> >  #include <linux/module.h>
> >  #include <linux/mutex.h>
> > +#include <linux/of.h>
> >  #include <linux/slab.h>
> >  
> >  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;
> > +}
> 
> I don't think this is actually needed. 
Yes, you are right

> Why not just assign the
> parent's fwnode for the mux as well?
will do it in next version

> 
> I'll add an example to the patch 6/6 in this series.
> 
> > +/**
> > + * 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);
> 
> So here you can then reuse switch_fwnode_match():
> 
> 	dev = class_find_device(role_class, NULL, fwnode, switch_fwnode_match);
I make a fast test, it works, thanks a lot Heikki

> 
> > +	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
> 
> thanks,
>

Patch
diff mbox series

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 <linux/device.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
+#include <linux/of.h>
 #include <linux/slab.h>
 
 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,