diff options
Diffstat (limited to 'Documentation/s390')
| -rw-r--r-- | Documentation/s390/driver-model.txt | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/Documentation/s390/driver-model.txt b/Documentation/s390/driver-model.txt index df09758bf3f..efb674eda4d 100644 --- a/Documentation/s390/driver-model.txt +++ b/Documentation/s390/driver-model.txt @@ -16,10 +16,12 @@ devices/ - 0.0.0000/0.0.0815/ - 0.0.0001/0.0.4711/ - 0.0.0002/ + - 0.1.0000/0.1.1234/ ... -In this example, device 0815 is accessed via subchannel 0, device 4711 via -subchannel 1, and subchannel 2 is a non-I/O subchannel. +In this example, device 0815 is accessed via subchannel 0 in subchannel set 0, +device 4711 via subchannel 1 in subchannel set 0, and subchannel 2 is a non-I/O +subchannel. Device 1234 is accessed via subchannel 0 in subchannel set 1. You should address a ccw device via its bus id (e.g. 0.0.4711); the device can be found under bus/ccw/devices/. @@ -97,7 +99,7 @@ is not available to the device driver. Each driver should declare in a MODULE_DEVICE_TABLE into which CU types/models and/or device types/models it is interested. This information can later be found -found in the struct ccw_device_id fields: +in the struct ccw_device_id fields: struct ccw_device_id { __u16 match_flags; @@ -208,6 +210,11 @@ Each ccwgroup device also provides an 'ungroup' attribute to destroy the device again (only when offline). This is a generic ccwgroup mechanism (the driver does not need to implement anything beyond normal removal routines). +A ccw device which is a member of a ccwgroup device carries a pointer to the +ccwgroup device in the driver_data of its device struct. This field must not be +touched by the driver - it should use the ccwgroup device's driver_data for its +private data. + To implement a ccwgroup driver, please refer to include/asm/ccwgroup.h. Keep in mind that most drivers will need to implement both a ccwgroup and a ccw driver (unless you have a meta ccw driver, like cu3088 for lcs and ctc). @@ -230,6 +237,8 @@ status - Can be 'online' or 'offline'. a channel path the user knows to be online, but the machine hasn't created a machine check for. +type - The physical type of the channel path. + 3. System devices ----------------- |