Serial Bus Protocol (SBP-2) Unsolicited Status Register Is Not Supported (303382)

RESOLUTION

To work around this issue, SBP-2 device developers can try either of the following methods.

Method 1

Have the target device return the unsolicited status with the current outstanding request.

If a device normally writes a status to the Unsolicited Status Register, it needs to, instead, return the intended status in the current request being processed by the device at the time for an unsolicited status. The Sbp2port.sys driver then passes that return status up the 1394/storage stack in the normal return mechanism (that is, the IO status field), and any upper-layer drivers can process that return status and perform the appropriate task.

Method 2

Have the target device create a device-specific command that simulates the Unsolicited Status Register.

In this scenario, the specific vendor-supplied device driver sends an out-of-band status request, which the target device pends until status is available. After the device determines a need for an "unsolicited" status to be sent, it can complete this pending command. The device driver can then take the appropriate action regarding the "unsolicited" status.

Note that both of the preceding methods require the device firmware to be responsible for the implementation of the workaround.