Tim Waugh wrote:
> Here's a patch that adds an ioctl to lp for controlling the timeout on
> parport_write. Tuning this might give a performance boost to people using
> FIFO/DMA transfers.
Ew, in jiffies which count in HZ, which is not only architecture
dependent, it varies on the same architecture, including x86...
This is why some people are inventing "fake jiffies", to support old
APIs which depend on HZ when the kernel is using a different value.
Even Linus has said "we want to avoid HZ-based values in the syscall
APIs". Check the archives on discussions of running x86s at 1000Hz.
Fred Barnes' ppdev ioctls work with struct tm:
#define PPGETTIME _IOR(PP_IOCTL, 0x95, struct timeval)
#define PPSETTIME _IOW(PP_IOCTL, 0x96, struct timeval)
So you can copy the code from there. May I suggest that?
enjoy,
-- Jamie
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Mon Jan 31 2000 - 21:00:22 EST