These patches change the behavior of the `COMEDI_BUFINFO` ioctl, which is used to manage buffer positions for a previously set up asynchronous acquisition command. It is used instead of the read and write file operations when the buffer has been mmapped. Patches 1 to 4 are fairly innocuous. Patches 5 to 8 change the error handling when the asynchronous command is no longer running, allow the subdevice to become "non-busy" automatically in more cases (causing subsequent calls to return `-EINVAL`), and report abnormal command termination with return value `-EPIPE` (which also makes the subdevice become non-busy). 1) staging: comedi: COMEDI_BUFINFO: get amount freed, not amount allocated 2) staging: comedi: COMEDI_BUFINFO: force bytes_read or bytes_written to 0 3) staging: comedi: COMEDI_BUFINFO: update buffer before becoming non-busy 4) staging: comedi: COMEDI_BUFINFO: force bytes_written to 0 if stopped 5) staging: comedi: COMEDI_BUFINFO: return error if no active command 6) staging: comedi: COMEDI_BUFINFO: become non-busy even if bytes_read is 0 7) staging: comedi: COMEDI_BUFINFO: return -EPIPE for abnormal read 8) staging: comedi: COMEDI_BUFINFO: terminate "write" command when stopped drivers/staging/comedi/comedi_fops.c | 84 +++++++++++++++++++----------------- 1 file changed, 44 insertions(+), 40 deletions(-) _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
