[v3,0/6] add USB Type-B GPIO connector driver
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Message ID 1554257354-7440-1-git-send-email-chunfeng.yun@mediatek.com
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  • add USB Type-B GPIO connector driver
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Chunfeng Yun April 3, 2019, 2:09 a.m. UTC
Because the USB Connector is introduced and the requirement of
usb-connector.txt binding, the old way using extcon to support
USB Dual-Role switch is now deprecated, meanwhile there is no
available common driver when use Type-B connector, typically
using an input GPIO to detect USB ID pin.
This patch series introduce a Type-B GPIO connector driver and try
to replace the function provided by extcon-usb-gpio driver.

v3 changes:
  1. add GPIO direction, and use fixed-regulator for GPIO controlled
    VBUS regulator suggested by Rob;
  2. rebuild fwnode_usb_role_switch_get() suggested by Andy and Heikki
  3. treat the type-B connector as a virtual device;
  4. change file name of driver again
  5. select USB_ROLE_SWITCH in mtu3/Kconfig suggested by Heikki
  6. rename ssusb_mode_manual_switch() to ssusb_mode_switch()

v2 changes:
 1. make binding clear, and add a extra compatible suggested by Hans

Chunfeng Yun (6):
  dt-bindings: connector: add optional properties for Type-B
  dt-bindings: usb: add binding for Type-B GPIO connector driver
  dt-bindings: usb: mtu3: add properties about USB Role Switch
  usb: roles: add API to get usb_role_switch by node
  usb: roles: add USB Type-B GPIO connector driver
  usb: mtu3: register a USB Role Switch for dual role mode

 .../bindings/connector/usb-connector.txt      |  14 +
 .../devicetree/bindings/usb/mediatek,mtu3.txt |  10 +-
 .../bindings/usb/typeb-conn-gpio.txt          |  49 +++
 drivers/usb/mtu3/Kconfig                      |   1 +
 drivers/usb/mtu3/mtu3.h                       |   5 +
 drivers/usb/mtu3/mtu3_debugfs.c               |   4 +-
 drivers/usb/mtu3/mtu3_dr.c                    |  47 ++-
 drivers/usb/mtu3/mtu3_dr.h                    |   6 +-
 drivers/usb/mtu3/mtu3_plat.c                  |   3 +-
 drivers/usb/roles/Kconfig                     |  11 +
 drivers/usb/roles/Makefile                    |   1 +
 drivers/usb/roles/class.c                     |  31 ++
 drivers/usb/roles/typeb-conn-gpio.c           | 301 ++++++++++++++++++
 include/linux/usb/role.h                      |   2 +
 14 files changed, 476 insertions(+), 9 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/usb/typeb-conn-gpio.txt
 create mode 100644 drivers/usb/roles/typeb-conn-gpio.c

Comments

Linus Walleij April 4, 2019, 4:35 p.m. UTC | #1
On Wed, Apr 3, 2019 at 9:09 AM Chunfeng Yun <chunfeng.yun@mediatek.com> wrote:

> Due to the requirement of usb-connector.txt binding, the old way
> using extcon to support USB Dual-Role switch is now deprecated
> when use Type-B connector.
> This patch introduces a driver of Type-B connector which typically
> uses an input GPIO to detect USB ID pin, and try to replace the
> function provided by extcon-usb-gpio driver
>
> Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
(...)
> +#include <linux/gpio.h>

If you need this include in a consumer, something is wrong. Just delete it,

> +       info->id_gpiod = devm_gpiod_get_from_of_node(
> +                               dev, child, "id-gpios", 0, GPIOD_IN, "idpin");

This is OK if the child does not have any Linux device (struct platform_device
etc) created from it. Is this the case?

Yours,
Linus Walleij
Chunfeng Yun April 8, 2019, 8:14 a.m. UTC | #2
Hi,
On Thu, 2019-04-04 at 23:35 +0700, Linus Walleij wrote:
> On Wed, Apr 3, 2019 at 9:09 AM Chunfeng Yun <chunfeng.yun@mediatek.com> wrote:
> 
> > Due to the requirement of usb-connector.txt binding, the old way
> > using extcon to support USB Dual-Role switch is now deprecated
> > when use Type-B connector.
> > This patch introduces a driver of Type-B connector which typically
> > uses an input GPIO to detect USB ID pin, and try to replace the
> > function provided by extcon-usb-gpio driver
> >
> > Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
> (...)
> > +#include <linux/gpio.h>
> 
> If you need this include in a consumer, something is wrong. Just delete it,
Ok
> 
> > +       info->id_gpiod = devm_gpiod_get_from_of_node(
> > +                               dev, child, "id-gpios", 0, GPIOD_IN, "idpin");
> 
> This is OK if the child does not have any Linux device (struct platform_device
> etc) created from it. Is this the case?
Yes, it is.

Thanks

> 
> Yours,
> Linus Walleij
Heikki Krogerus April 10, 2019, 10:22 a.m. UTC | #3
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,
Heikki Krogerus April 10, 2019, 10:24 a.m. UTC | #4
On Wed, Apr 03, 2019 at 10:09:14AM +0800, Chunfeng Yun wrote:
> +static int ssusb_role_sw_register(struct otg_switch_mtk *otg_sx)
> +{
> +	struct usb_role_switch_desc role_sx_desc = { 0 };
> +	struct ssusb_mtk *ssusb =
> +		container_of(otg_sx, struct ssusb_mtk, otg_switch);
> +
> +	if (!otg_sx->role_sw_used)
> +		return 0;
> +
> +	role_sx_desc.set = ssusb_role_sw_set;
> +	role_sx_desc.get = ssusb_role_sw_get;

        role_sw_desc.fwnode = dev_fwnode(ssusb->dev);

> +	otg_sx->role_sw = usb_role_switch_register(ssusb->dev, &role_sx_desc);
> +
> +	return PTR_ERR_OR_ZERO(otg_sx->role_sw);
> +}

thanks,
Chunfeng Yun April 11, 2019, 1:05 a.m. UTC | #5
On Wed, 2019-04-10 at 13:24 +0300, Heikki Krogerus wrote:
> On Wed, Apr 03, 2019 at 10:09:14AM +0800, Chunfeng Yun wrote:
> > +static int ssusb_role_sw_register(struct otg_switch_mtk *otg_sx)
> > +{
> > +	struct usb_role_switch_desc role_sx_desc = { 0 };
> > +	struct ssusb_mtk *ssusb =
> > +		container_of(otg_sx, struct ssusb_mtk, otg_switch);
> > +
> > +	if (!otg_sx->role_sw_used)
> > +		return 0;
> > +
> > +	role_sx_desc.set = ssusb_role_sw_set;
> > +	role_sx_desc.get = ssusb_role_sw_get;
> 
>         role_sw_desc.fwnode = dev_fwnode(ssusb->dev);
Ok, thanks

> 
> > +	otg_sx->role_sw = usb_role_switch_register(ssusb->dev, &role_sx_desc);
> > +
> > +	return PTR_ERR_OR_ZERO(otg_sx->role_sw);
> > +}
> 
> thanks,
>
Chunfeng Yun April 11, 2019, 3:11 a.m. UTC | #6
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,
>