CDROM: Fix START STOP UNIT preventing drive use #234
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This fixes an issue where Macs on reboot would stop the drive and never try to restart it. This also matches observed behavior on a Matshita drive, which would just spin down in response to this command and continue to indicate a good response to TEST UNIT READY as long as a disk was in the drive.
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I wonder if the same issue might affect harddrive emulation also? |
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This fixes an issue I observed where two different Macs would issue a START STOP UNIT with LoEj=0,Start=0 to stop a virtual CD-ROM drive during restart but never try to reinitialize the drive afterwards. This makes it look like the device has "disappeared" until it is power cycled.
I also tested this on a modern Linux system using
sg3_utilsagainst an older Matshita drive. Executing START STOP UNIT as above the unit would just spin down in response and continue to indicate a good condition to TEST UNIT READY as long as a disk was in the drive. Media commands issued while in this state would cause it to spin back up again without a matching START STOP UNIT command with Start=1.To be candid, I'm not 100% confident that the above tests are robust: there may be a re-initialization issue for the device during bus reset or a Linux driver interfering with the utility tests.