diff options
author | Kannappan R <r.kannappan@intel.com> | 2025-02-20 16:13:39 +0200 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-02-21 10:45:32 +0100 |
commit | c749f058b4371430a8338e1ca72b9ae38fef613b (patch) | |
tree | 7379b9e1ac873df7b977772c99d8217ac446cec5 /include/linux/usb.h | |
parent | 0a86e49acfbb4f97ba86f05eb250f4c65c8bec0d (diff) |
USB: core: Add eUSB2 descriptor and parsing in USB core
Add support for the 'eUSB2 Isochronous Endpoint Companion Descriptor'
introduced in the recent USB 2.0 specification 'USB 2.0 Double Isochronous
IN Bandwidth' ECN.
It allows embedded USB2 (eUSB2) devices to report and use higher bandwidths
for isochronous IN transfers in order to support higher camera resolutions
on the lid of laptops and tablets with minimal change to the USB2 protocol.
The motivation for expanding USB 2.0 is further clarified in an additional
Embedded USB2 version 2.0 (eUSB2v2) supplement to the USB 2.0
specification. It points out this is optimized for performance, power and
cost by using the USB 2.0 low-voltage, power efficient PHY and half-duplex
link for the asymmetric camera bandwidth needs, avoiding the costly and
complex full-duplex USB 3.x symmetric link and gigabit receivers.
eUSB2 devices that support the higher isochronous IN bandwidth and the new
descriptor can be identified by their device descriptor bcdUSB value of
0x0220
Co-developed-by: Amardeep Rai <amardeep.rai@intel.com>
Signed-off-by: Amardeep Rai <amardeep.rai@intel.com>
Signed-off-by: Kannappan R <r.kannappan@intel.com>
Co-developed-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20250220141339.1939448-1-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/linux/usb.h')
-rw-r--r-- | include/linux/usb.h | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/include/linux/usb.h b/include/linux/usb.h index cfa8005e24f9..b46738701f8d 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -51,6 +51,7 @@ struct ep_device; * @desc: descriptor for this endpoint, wMaxPacketSize in native byteorder * @ss_ep_comp: SuperSpeed companion descriptor for this endpoint * @ssp_isoc_ep_comp: SuperSpeedPlus isoc companion descriptor for this endpoint + * @eusb2_isoc_ep_comp: eUSB2 isoc companion descriptor for this endpoint * @urb_list: urbs queued to this endpoint; maintained by usbcore * @hcpriv: for use by HCD; typically holds hardware dma queue head (QH) * with one or more transfer descriptors (TDs) per urb @@ -64,9 +65,10 @@ struct ep_device; * descriptor within an active interface in a given USB configuration. */ struct usb_host_endpoint { - struct usb_endpoint_descriptor desc; - struct usb_ss_ep_comp_descriptor ss_ep_comp; - struct usb_ssp_isoc_ep_comp_descriptor ssp_isoc_ep_comp; + struct usb_endpoint_descriptor desc; + struct usb_ss_ep_comp_descriptor ss_ep_comp; + struct usb_ssp_isoc_ep_comp_descriptor ssp_isoc_ep_comp; + struct usb_eusb2_isoc_ep_comp_descriptor eusb2_isoc_ep_comp; struct list_head urb_list; void *hcpriv; struct ep_device *ep_dev; /* For sysfs info */ |