struct ladder_device {
        struct ladder_device_state states[CPUIDLE_STATE_MAX];
-       int last_state_idx;
 };
 
 static DEFINE_PER_CPU(struct ladder_device, ladder_devices);
  * @old_idx: the current state index
  * @new_idx: the new target state index
  */
-static inline void ladder_do_selection(struct ladder_device *ldev,
+static inline void ladder_do_selection(struct cpuidle_device *dev,
+                                      struct ladder_device *ldev,
                                       int old_idx, int new_idx)
 {
        ldev->states[old_idx].stats.promotion_count = 0;
        ldev->states[old_idx].stats.demotion_count = 0;
-       ldev->last_state_idx = new_idx;
+       dev->last_state_idx = new_idx;
 }
 
 /**
 {
        struct ladder_device *ldev = this_cpu_ptr(&ladder_devices);
        struct ladder_device_state *last_state;
-       int last_residency, last_idx = ldev->last_state_idx;
+       int last_residency, last_idx = dev->last_state_idx;
        int first_idx = drv->states[0].flags & CPUIDLE_FLAG_POLLING ? 1 : 0;
        int latency_req = cpuidle_governor_latency_req(dev->cpu);
 
        /* Special case when user has set very strict latency requirement */
        if (unlikely(latency_req == 0)) {
-               ladder_do_selection(ldev, last_idx, 0);
+               ladder_do_selection(dev, ldev, last_idx, 0);
                return 0;
        }
 
                last_state->stats.promotion_count++;
                last_state->stats.demotion_count = 0;
                if (last_state->stats.promotion_count >= last_state->threshold.promotion_count) {
-                       ladder_do_selection(ldev, last_idx, last_idx + 1);
+                       ladder_do_selection(dev, ldev, last_idx, last_idx + 1);
                        return last_idx + 1;
                }
        }
                        if (drv->states[i].exit_latency <= latency_req)
                                break;
                }
-               ladder_do_selection(ldev, last_idx, i);
+               ladder_do_selection(dev, ldev, last_idx, i);
                return i;
        }
 
                last_state->stats.demotion_count++;
                last_state->stats.promotion_count = 0;
                if (last_state->stats.demotion_count >= last_state->threshold.demotion_count) {
-                       ladder_do_selection(ldev, last_idx, last_idx - 1);
+                       ladder_do_selection(dev, ldev, last_idx, last_idx - 1);
                        return last_idx - 1;
                }
        }
        struct ladder_device_state *lstate;
        struct cpuidle_state *state;
 
-       ldev->last_state_idx = first_idx;
+       dev->last_state_idx = first_idx;
 
        for (i = first_idx; i < drv->state_count; i++) {
                state = &drv->states[i];
  */
 static void ladder_reflect(struct cpuidle_device *dev, int index)
 {
-       struct ladder_device *ldev = this_cpu_ptr(&ladder_devices);
        if (index > 0)
-               ldev->last_state_idx = index;
+               dev->last_state_idx = index;
 }
 
 static struct cpuidle_governor ladder_governor = {
 
  * @time_span_ns: Time between idle state selection and post-wakeup update.
  * @sleep_length_ns: Time till the closest timer event (at the selection time).
  * @states: Idle states data corresponding to this CPU.
- * @last_state: Idle state entered by the CPU last time.
  * @interval_idx: Index of the most recent saved idle interval.
  * @intervals: Saved idle duration values.
  */
        u64 time_span_ns;
        u64 sleep_length_ns;
        struct teo_idle_state states[CPUIDLE_STATE_MAX];
-       int last_state;
        int interval_idx;
        unsigned int intervals[INTERVALS];
 };
                 */
                measured_us = sleep_length_us;
        } else {
-               unsigned int lat = drv->states[cpu_data->last_state].exit_latency;
+               unsigned int lat;
+
+               lat = drv->states[dev->last_state_idx].exit_latency;
 
                measured_us = ktime_to_us(cpu_data->time_span_ns);
                /*
        int max_early_idx, idx, i;
        ktime_t delta_tick;
 
-       if (cpu_data->last_state >= 0) {
+       if (dev->last_state_idx >= 0) {
                teo_update(drv, dev);
-               cpu_data->last_state = -1;
+               dev->last_state_idx = -1;
        }
 
        cpu_data->time_span_ns = local_clock();
 {
        struct teo_cpu *cpu_data = per_cpu_ptr(&teo_cpus, dev->cpu);
 
-       cpu_data->last_state = state;
+       dev->last_state_idx = state;
        /*
         * If the wakeup was not "natural", but triggered by one of the safety
         * nets, assume that the CPU might have been idle for the entire sleep