663c30d082
The USB 3.0 bus specification added an "Endpoint Companion" descriptor that is supposed to follow all SuperSpeed Endpoint descriptors. This descriptor is used to extend the bus protocol to allow more packets to be sent to an endpoint per "microframe". The word microframe was removed from the USB 3.0 specification because the host controller does not send Start Of Frame (SOF) symbols down the USB 3.0 wires. The descriptor defines a bMaxBurst field, which indicates the number of packets of wMaxPacketSize that a SuperSpeed device can send or recieve in a service interval. All non-control endpoints may set this value as high as 16 packets (bMaxBurst = 15). The descriptor also allows isochronous endpoints to further specify that they can send and receive multiple bursts per service interval. The bmAttributes allows them to specify a "Mult" of up to 3 (bmAttributes = 2). Bulk endpoints use bmAttributes to report the number of "Streams" they support. This was an extension of the endpoint pipe concept to allow multiple mass storage device commands to be outstanding for one bulk endpoint at a time. This should allow USB 3.0 mass storage devices to support SCSI command queueing. Bulk endpoints can say they support up to 2^16 (65,536) streams. The information in the endpoint companion descriptor must be stored with the other device, config, interface, and endpoint descriptors because the host controller needs to access them quickly, and we need to install some default values if a SuperSpeed device doesn't provide an endpoint companion descriptor. Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> |
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| acpi | ||
| asm-generic | ||
| crypto | ||
| drm | ||
| keys | ||
| linux | ||
| math-emu | ||
| media | ||
| mtd | ||
| net | ||
| pcmcia | ||
| rdma | ||
| rxrpc | ||
| scsi | ||
| sound | ||
| trace | ||
| video | ||
| xen | ||
| Kbuild | ||