diff options
Diffstat (limited to 'drivers/staging/vme/vme_api.txt')
| -rw-r--r-- | drivers/staging/vme/vme_api.txt | 60 |
1 files changed, 30 insertions, 30 deletions
diff --git a/drivers/staging/vme/vme_api.txt b/drivers/staging/vme/vme_api.txt index 03f48134706..53abf7e7cb4 100644 --- a/drivers/staging/vme/vme_api.txt +++ b/drivers/staging/vme/vme_api.txt @@ -18,24 +18,37 @@ registration function. The structure is as follows: struct vme_driver { struct list_head node; - char *name; - const struct vme_device_id *bind_table; - int (*probe) (struct vme_dev *); - int (*remove) (struct vme_dev *); - void (*shutdown) (void); - struct device_driver driver; + const char *name; + int (*match)(struct vme_dev *); + int (*probe)(struct vme_dev *); + int (*remove)(struct vme_dev *); + void (*shutdown)(void); + struct device_driver driver; + struct list_head devices; + unsigned int ndev; }; -At the minimum, the '.name', '.probe' and '.bind_table' elements of this -structure should be correctly set. The '.name' element is a pointer to a string -holding the device driver's name. The '.probe' element should contain a pointer -to the probe routine. +At the minimum, the '.name', '.match' and '.probe' elements of this structure +should be correctly set. The '.name' element is a pointer to a string holding +the device driver's name. -The arguments of the probe routine are as follows: +The '.match' function allows controlling the number of devices that need to +be registered. The match function should return 1 if a device should be +probed and 0 otherwise. This example match function (from vme_user.c) limits +the number of devices probed to one: - probe(struct vme_dev *dev); + #define USER_BUS_MAX 1 + ... + static int vme_user_match(struct vme_dev *vdev) + { + if (vdev->id.num >= USER_BUS_MAX) + return 0; + return 1; + } -The device structure looks like the following: +The '.probe' element should contain a pointer to the probe routine. The +probe routine is passed a 'struct vme_dev' pointer as an argument. The +'struct vme_dev' structure looks like the following: struct vme_dev { struct vme_device_id id; @@ -49,25 +62,12 @@ contains information useful for the probe function: struct vme_device_id { int bus; int slot; + int num; }; -'bus' is the number of the bus the device being probed is on. 'slot' refers -to the specific slot on the VME bus. - -The '.bind_table' is a pointer to an array of type 'vme_device_id': - - struct vme_device_id { - int bus; - int slot; - }; - -Each structure in this array should provide a bus and slot number where the core -should probe, using the driver's probe routine, for a device on the specified -VME bus. - -The VME subsystem supports a single VME driver per 'slot'. There are considered -to be 32 slots per bus, one for each slot-ID as defined in the ANSI/VITA 1-1994 -specification and are analogious to the physical slots on the VME backplane. +Here, 'bus' is the number of the bus the device being probed is on. 'slot' +refers to the specific slot on the VME bus. The 'num' field refers to the +sequential device ID for this specific driver. A function is also provided to unregister the driver from the VME core and is usually called from the device driver's exit routine: |