hi
The USB controller in our SOC can support otg/ehci/udc, and there is a
PHY around the controller. It means that when we want to enable otg or
ehci or udc, we have to enable the PHY.
Then i want to add a PHY driver, but the PHY does not bind to OTG. It
means that if we want only udc fucntion, we still need the phy. The
struct usb_phy has a pointer to usb_otg. To make use of the phy
driver, can i have the following callings?
1. write a phy driver, and initialize phy->init and phy->shutdown.
Then in probe function invoke usb_add_phy(phy, USB_PHY_TYPE_USB2)
2. in the udc driver
in probe function, call usb_get_phy(USB_PHY_TYPE_USB2), and when
want to start udc, call phy->init() to initialize the PHY, and when
want to stop udc, call phy->shutdown to shutdown the phy
when udc is started, and usally we will check whether phy->otg is
NULL or not, if it is not NULL, invoke otg_set_peripheral to set the
OTG to be device-B. It means that if we have otg enabled, the phy->otg
will not be NULL, otherwise we only have udc supported.
3. in the otg driver
in the probe function, initialize the otg(struct usb_otg), then
call usb_get_phy(USB_PHY_TYPE_USB2), and set phy->otg = otg.
4. in the ehci driver
in the probe function, call usb_get_phy(USB_PHY_TYPE_USB2), and
when want to enable ehci, call phy->init first.
when start ehci, we will check whether phy->otg is NULL or not, if
it is not NULL, invoke otg_set_host to make otg be host-A.
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
