I have been asked to modify an existing SD driver to support more than one instance of the hardware. There are 3 slots on the evaluation board and 2 of the slots have the same hardware device in them. When I load the driver my spio_probe function gets called once (I expected twice). So I assume that is some address or bus pointer that I need to include when doing register reads and writes to distinguish which hardware I am talking to.

I would really appreciate some help knowing how to get two call backs to my spio_probe function, or how to register two devices on the SD bus.

Thanks,
M-

Normally for any pluggable bus there is a bus driver which can walk the bus and find devices. It then calls the appropriate device driver for each device found. The device driver creates a device instance and configures the device. The PCI bus driver, for example, uses the vendor/device ID to select which device driver to call. For PCI, this is only done at boot time unless you have hotplug support, which requires leaving room in the device tables for devices found after boot.

I don't recognize spio (special-purpose I/O?) or your use of SD (sd is SCSI Disk). I assume these are your proprietary devices. Most likely you need to trigger the bus driver somehow to scan the bus for devices after you load your driver. A SCSI controller (bus) driver uses the obscure syntax "echo '- - -' > /sys/class/scsi_host/host0/scan" to trigger a scan for new disks attached to host adapter 0. This should be documented for your bus driver.