static void analyze_ambient_temp()

in char/bbc_envctrl.c [169:222]

• 45 lines of code
• 13 McCabe index (conditional complexity)

static void analyze_ambient_temp(struct bbc_cpu_temperature *tp, unsigned long *last_warn, int tick)
{
	int ret = 0;

	if (time_after(jiffies, (*last_warn + WARN_INTERVAL))) {
		if (tp->curr_amb_temp >=
		    amb_temp_limits[tp->index].high_warn) {
			printk(KERN_WARNING "temp%d: "
			       "Above safe ambient operating temperature, %d C.\n",
			       tp->index, (int) tp->curr_amb_temp);
			ret = 1;
		} else if (tp->curr_amb_temp <
			   amb_temp_limits[tp->index].low_warn) {
			printk(KERN_WARNING "temp%d: "
			       "Below safe ambient operating temperature, %d C.\n",
			       tp->index, (int) tp->curr_amb_temp);
			ret = 1;
		}
		if (ret)
			*last_warn = jiffies;
	} else if (tp->curr_amb_temp >= amb_temp_limits[tp->index].high_warn ||
		   tp->curr_amb_temp < amb_temp_limits[tp->index].low_warn)
		ret = 1;

	/* Now check the shutdown limits. */
	if (tp->curr_amb_temp >= amb_temp_limits[tp->index].high_shutdown ||
	    tp->curr_amb_temp < amb_temp_limits[tp->index].low_shutdown) {
		do_envctrl_shutdown(tp);
		ret = 1;
	}

	if (ret) {
		tp->fan_todo[FAN_AMBIENT] = FAN_FULLBLAST;
	} else if ((tick & (8 - 1)) == 0) {
		s8 amb_goal_hi = amb_temp_limits[tp->index].high_warn - 10;
		s8 amb_goal_lo;

		amb_goal_lo = amb_goal_hi - 3;

		/* We do not try to avoid 'too cold' events.  Basically we
		 * only try to deal with over-heating and fan noise reduction.
		 */
		if (tp->avg_amb_temp < amb_goal_hi) {
			if (tp->avg_amb_temp >= amb_goal_lo)
				tp->fan_todo[FAN_AMBIENT] = FAN_SAME;
			else
				tp->fan_todo[FAN_AMBIENT] = FAN_SLOWER;
		} else {
			tp->fan_todo[FAN_AMBIENT] = FAN_FASTER;
		}
	} else {
		tp->fan_todo[FAN_AMBIENT] = FAN_SAME;
	}
}