DESCRIPTIONThe driver provides support for all SCSI devices of the environmental services class that are attached to the system through a supported SCSI Host Adapter, as well as emulated support for SAF-TE (SCSI Accessible Fault Tolerant Enclosures). The environmental services class generally are enclosure devices that provide environmental information such as number of power supplies (and state), temperature, device slots, and so on.
A SCSI Host adapter must also be separately configured into the system before a SCSI Environmental Services device can be configured.
KERNEL CONFIGURATIONIt is only necessary to explicitly configure one device; data structures are dynamically allocated as devices are found on the SCSI bus.
A separate option, SES_ENABLE_PASSTHROUGH may be specified to allow the driver to perform functions on devices of other classes that claim to also support functionality.
IOCTLSThe following ioctl(2) calls apply to devices. They are defined in the header file In cam/scsi/scsi_ses.h (q.v.).
- Used to find out how many objects are driven by this particular device instance.
- Read, from the kernel, an array of SES objects which contains the object identifier, which subenclosure it is in, and the type of the object.
- Get the overall enclosure status.
- Set the overall enclosure status.
- Get the status of a particular object.
- Set the status of a particular object.
- Get the associated help text for an object (not yet implemented). devices often have descriptive text for an object which can tell you things like location (e.g., "left power supply").
- Initialize the enclosure.
EXAMPLE USAGEThe files contained in In usr/share/examples/ses show simple mechanisms for how to use these interfaces, as well as a very stupid simple monitoring daemon.
- /dev/ses N
- The Nth SES device.
DIAGNOSTICSWhen the kernel is configured with DEBUG enabled, the first open to an SES device will spit out overall enclosure parameters to the console.
HISTORYThe driver was written for the CAM SCSI subsystem by Matthew Jacob. This is a functional equivalent of a similar driver available in Solaris, Release 7.