Hi Roger, 2016-08-01 21:23 GMT+09:00 Roger Quadros <rogerq@xxxxxx>: > Hi, > > On 09/06/16 12:32, Chanwoo Choi wrote: >> Hi, >> >> On 2016년 06월 09일 17:39, Krzysztof Kozlowski wrote: >>> >>> Hi, >>> >>> >>> On 06/09/2016 10:35 AM, Chanwoo Choi wrote: >>>> Hi, >>>> >>>> It is good to support USB_ID and USB_VBUS by extcon. >>>> >>>> But, >>>> there is some issue about adding the new cable type for >>>> both EXTCON_USB_ID and EXTCON_USB_VBUS >>>> >>>> I think that the ID and VBUS state are not cable type >>>> Instead, ID and VBUS state are the property of USB cable. >>>> >>>> So, I'd like to add the following function to support >>>> the property of each cable as following: >>>> The client driver can get the state of property by using >>>> the extcon_get_cable_property_state(). >>>> >>>> - int extcon_get_cable_property_state(struct extcon_dev *edev, >>>> unsigned int id, >>>> enum extcon_property property); >>>> - int extcon_set_cable_property_state(struct extcon_dev *edev, >>>> unsigned int id, >>>> enum extcon_property property, >>>> unsigned int state); >>>> >>>> For example, >>>> In extcon-usb-gpio.c, set state of property as follwoing: >>>> extcon_set_cable_property_state(edev, EXTCON_USB, EXTCON_USB_PROP_ID, 1); >>>> extcon_set_cable_property_state(edev, EXTCON_USB, EXTCON_USB_PROP_VBUS, 1); >>>> >>>> >>>> In the extcon client driver, get state of property as following: >>>> id_state = extcon_get_cable_property_state(edev, EXTCON_USB, EXTCON_USB_PROP_ID); >>>> vbus_state = extcon_get_cable_property_state(edev, EXTCON_USB, EXTCON_USB_PROP_VUBS); >>> >>> How one can receive notifications with this API? >> >> I think that the extcon don't support the notification only for property. >> When USB or USB_HOST cable state is changed, the client driver >> call the extcon_get_cable_property_state() to read the state of property. >> >> Namely, the property depend on the specific external connector. >> >>> >>> Last time you wrote, at the end of discussion: >>> http://thread.gmane.org/gmane.linux.kernel/1923192/focus=1923193 >>>> IMO, if some usb driver check both id and vbus pin at the same time, >>>> the usb driver can know the both id and vbus pin state through only >>> one notifier event. >>>> >>>> Also, >>>> If some usb driver want to know the state of id pin except of vbus state, >>>> when receiving following events, id pin is low. >>>> #define EXTCON_USB_ID_L_VBUS_L0 >>>> #define EXTCON_USB_ID_L_VBUS_H1 >>>> when receiving following events, id pin is high. >>>> #define EXTCON_USB_ID_H_VBUS_L2 >>>> #define EXTCON_USB_ID_H_VBUS_H3 >>>> Also, some usb driver would catch the vbus pin state with same method. >>>> >>>> But, it is just my opinion. We may use following notifier events for >>> each pin. >>>> We need to discuss it. >>>> #define EXTCON_USB_ID_LOW >>>> #define EXTCON_USB_ID_HIGH >>>> #define EXTCON_USB_VBUS_LOW >>>> #define EXTCON_USB_VBUS_HIGH >>> >>> ... all other participants agreed on that conclusion. So why change of >>> view point now? >> >> Unitl now, the extcon framework only handle the state of external connector(cable). >> - The state of external connector is either attached or detached. >> >> I think that ID and VBUS are not external connector(cable). >> The ID and VBUS are more appropriate as property than new type of external connector. >> > > Was there any conclusion on how we can support raw ID and VBUS events with extcon? The extcon will support the USB_ID and USB_VBUS as extcon property. I'm sending the patches[1] for extcon property. [1] https://lkml.org/lkml/2016/8/1/25 : [PATCH v2 0/6] extcon: Add the support for extcon type and property Thanks, Chanwoo Choi -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
