On Friday 13 December 2013, Sergei Ianovich wrote: > +void nsleep(unsigned long nanosec) > +{ > + ktime_t t = ns_to_ktime(nanosec); > + long state = current->state; > + > + __set_current_state(TASK_UNINTERRUPTIBLE); > + schedule_hrtimeout(&t, HRTIMER_MODE_REL); > + __set_current_state(state); > +} > + > +static void lp8x4x_slot_reset_AO(struct lp8x4x_slot *s) > +{ > + int i; > + mutex_lock(&s->lock); > + for (i = 0; i < s->AO_len; i++) > + s->AO[i] = 0x2000; > + iowrite8(0x00, s->data_addr); > + nsleep(450); > + iowrite8(0xff, s->data_addr); > + mutex_unlock(&s->lock); > +} Have you checked that the nsleep definition actually does the right thing here? 450 nanoseconds must be close the latency you get from calling schedule_hrtimeout(). I'd suggest using either ndelay() or usleep_range() instead, depending on your needs. If nsleep is really useful here, we should probably add that as a generic API rather than having it in one driver. Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html