On Tuesday, November 04, 2014 11:09 AM, Ian Abbott wrote: > This series of patches adds a couple of ioctl codes to the Comedi core > to allow the current "read" and "write" subdevice to be changed after > opening the comedi device. The current read and write subdevice > information is stored in file private data allocated for the lifetime of > the file object, so the notion of current "read" and "write" subdevice > is local to the file object and does not alter anything in the main > control structure for the comedi device. An extra level of indirection > is now required to access the main control structure. > > I've tested the multiple "read" subdevice case using a modified version > of the "comedi_test" module (modifying it to clone the existing AI > subdevice), and a modified version of the "comedi_test" application > (part of the "comedilib" installation) modified to use the new ioctls. > There isn't any support in comedilib itself yet. > > 1) staging: comedi: prepare support for per-file read and write > subdevices > 2) staging: comedi: add ioctls to set per-file read and write subdevice > > drivers/staging/comedi/comedi.h | 2 + > drivers/staging/comedi/comedi_compat32.c | 2 + > drivers/staging/comedi/comedi_fops.c | 217 +++++++++++++++++++++++++++---- > 3 files changed, 196 insertions(+), 25 deletions(-) Ian, If I understand this correctly, the user can now open the "comediX" device which will give then access to the default dev->read_subdev and dev->write_subdev. They can then use the new ioctls to change the read/write subdevice and use them without having the open the "comediX_subdY" devices. If this is correct it seems like a good idea. Reviewed-by: H Hartley Sweeten <hsweeten@xxxxxxxxxxxxxxxxxxx> Also, does this mean we can get rid of comedi_alloc_subdevice_minor() and the "comediX_sudbY" stuff? Regards, Hartley _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
