1*4882a593SmuzhiyunWhat: /sys/bus/css/devices/.../type 2*4882a593SmuzhiyunDate: March 2008 3*4882a593SmuzhiyunContact: Cornelia Huck <cornelia.huck@de.ibm.com> 4*4882a593Smuzhiyun linux-s390@vger.kernel.org 5*4882a593SmuzhiyunDescription: Contains the subchannel type, as reported by the hardware. 6*4882a593Smuzhiyun This attribute is present for all subchannel types. 7*4882a593Smuzhiyun 8*4882a593SmuzhiyunWhat: /sys/bus/css/devices/.../modalias 9*4882a593SmuzhiyunDate: March 2008 10*4882a593SmuzhiyunContact: Cornelia Huck <cornelia.huck@de.ibm.com> 11*4882a593Smuzhiyun linux-s390@vger.kernel.org 12*4882a593SmuzhiyunDescription: Contains the module alias as reported with uevents. 13*4882a593Smuzhiyun It is of the format css:t<type> and present for all 14*4882a593Smuzhiyun subchannel types. 15*4882a593Smuzhiyun 16*4882a593SmuzhiyunWhat: /sys/bus/css/drivers/io_subchannel/.../chpids 17*4882a593SmuzhiyunDate: December 2002 18*4882a593SmuzhiyunContact: Cornelia Huck <cornelia.huck@de.ibm.com> 19*4882a593Smuzhiyun linux-s390@vger.kernel.org 20*4882a593SmuzhiyunDescription: Contains the ids of the channel paths used by this 21*4882a593Smuzhiyun subchannel, as reported by the channel subsystem 22*4882a593Smuzhiyun during subchannel recognition. 23*4882a593Smuzhiyun 24*4882a593Smuzhiyun Note: This is an I/O-subchannel specific attribute. 25*4882a593SmuzhiyunUsers: s390-tools, HAL 26*4882a593Smuzhiyun 27*4882a593SmuzhiyunWhat: /sys/bus/css/drivers/io_subchannel/.../pimpampom 28*4882a593SmuzhiyunDate: December 2002 29*4882a593SmuzhiyunContact: Cornelia Huck <cornelia.huck@de.ibm.com> 30*4882a593Smuzhiyun linux-s390@vger.kernel.org 31*4882a593SmuzhiyunDescription: Contains the PIM/PAM/POM values, as reported by the 32*4882a593Smuzhiyun channel subsystem when last queried by the common I/O 33*4882a593Smuzhiyun layer (this implies that this attribute is not necessarily 34*4882a593Smuzhiyun in sync with the values current in the channel subsystem). 35*4882a593Smuzhiyun 36*4882a593Smuzhiyun Note: This is an I/O-subchannel specific attribute. 37*4882a593SmuzhiyunUsers: s390-tools, HAL 38*4882a593Smuzhiyun 39*4882a593SmuzhiyunWhat: /sys/bus/css/devices/.../driver_override 40*4882a593SmuzhiyunDate: June 2019 41*4882a593SmuzhiyunContact: Cornelia Huck <cohuck@redhat.com> 42*4882a593Smuzhiyun linux-s390@vger.kernel.org 43*4882a593SmuzhiyunDescription: This file allows the driver for a device to be specified. When 44*4882a593Smuzhiyun specified, only a driver with a name matching the value written 45*4882a593Smuzhiyun to driver_override will have an opportunity to bind to the 46*4882a593Smuzhiyun device. The override is specified by writing a string to the 47*4882a593Smuzhiyun driver_override file (echo vfio-ccw > driver_override) and 48*4882a593Smuzhiyun may be cleared with an empty string (echo > driver_override). 49*4882a593Smuzhiyun This returns the device to standard matching rules binding. 50*4882a593Smuzhiyun Writing to driver_override does not automatically unbind the 51*4882a593Smuzhiyun device from its current driver or make any attempt to 52*4882a593Smuzhiyun automatically load the specified driver. If no driver with a 53*4882a593Smuzhiyun matching name is currently loaded in the kernel, the device 54*4882a593Smuzhiyun will not bind to any driver. This also allows devices to 55*4882a593Smuzhiyun opt-out of driver binding using a driver_override name such as 56*4882a593Smuzhiyun "none". Only a single driver may be specified in the override, 57*4882a593Smuzhiyun there is no support for parsing delimiters. 58*4882a593Smuzhiyun 59*4882a593Smuzhiyun Note that unlike the mechanism of the same name for pci, this 60*4882a593Smuzhiyun file does not allow to override basic matching rules. I.e., 61*4882a593Smuzhiyun the driver must still match the subchannel type of the device. 62