Hi, On 03/07/2017 01:43 AM, Yuyang Du wrote:
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There is also other side, the protocol. Probably we won't be able to handle this using exiting protocol messages. At first glance I see at least one reason: Documentation/usb/usbip_protocol.txt: USBIP_RET_SUBMIT: Reply for submitting an URB Offset | Length | Value | Description -----------+--------+------------+--------------------------------------------------- 0 | 4 | 0x00000003 | command -----------+--------+------------+--------------------------------------------------- 4 | 4 | | seqnum: URB sequence number -----------+--------+------------+--------------------------------------------------- 8 | 4 | | devid -----------+--------+------------+--------------------------------------------------- 0xC | 4 | | direction: 0: USBIP_DIR_OUT | | | 1: USBIP_DIR_IN -----------+--------+------------+--------------------------------------------------- 0x10 | 4 | | ep: endpoint number -----------+--------+------------+--------------------------------------------------- 0x14 | 4 | | status: zero for successful URB transaction, | | | otherwise some kind of error happened. -----------+--------+------------+--------------------------------------------------- 0x18 | 4 | n | actual_length: number of URB data bytes -----------+--------+------------+--------------------------------------------------- 0x1C | 4 | | start_frame: for an ISO frame the actually | | | selected frame for transmit. -----------+--------+------------+--------------------------------------------------- 0x20 | 4 | | number_of_packets -----------+--------+------------+--------------------------------------------------- 0x24 | 4 | | error_count -----------+--------+------------+--------------------------------------------------- 0x28 | 8 | | setup: data bytes for USB setup, filled with | | | zeros if not used -----------+--------+------------+--------------------------------------------------- 0x30 | n | | URB data bytes. For ISO transfers the padding | | | between each ISO packets is not transmitted. As you see we have a field for devid, direction and ep but we don't have a field for stream id.Then, as Oliver pointed out, if we don't need bulk streams transfer type, the current protocol should work fine, right?
Yeah it should or at least for now I don't see any obvious reason why it could not work.
Cheers, -- Krzysztof Opasiak Samsung R&D Institute Poland Samsung Electronics -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
