cpufreq: expose a cpufreq_quick_get_max routine

This allows drivers and other code to get the max reported CPU frequency.
Initial use is for scaling ring frequency with GPU frequency in the i915
driver.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NKeith Packard <keithp@keithp.com>

drivers/cpufreq/cpufreq.c

@@ -1199,6 +1199,26 @@ unsigned int cpufreq_quick_get(unsigned int cpu)
 }
 EXPORT_SYMBOL(cpufreq_quick_get);
 
+/**
+ * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU
+ * @cpu: CPU number
+ *
+ * Just return the max possible frequency for a given CPU.
+ */
+unsigned int cpufreq_quick_get_max(unsigned int cpu)
+{
+	struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
+	unsigned int ret_freq = 0;
+
+	if (policy) {
+		ret_freq = policy->max;
+		cpufreq_cpu_put(policy);
+	}
+
+	return ret_freq;
+}
+EXPORT_SYMBOL(cpufreq_quick_get_max);
+
 
 static unsigned int __cpufreq_get(unsigned int cpu)
 {

include/linux/cpufreq.h

@@ -324,11 +324,16 @@ static inline unsigned int cpufreq_get(unsigned int cpu)
 /* query the last known CPU freq (in kHz). If zero, cpufreq couldn't detect it */
 #ifdef CONFIG_CPU_FREQ
 unsigned int cpufreq_quick_get(unsigned int cpu);
+unsigned int cpufreq_quick_get_max(unsigned int cpu);
 #else
 static inline unsigned int cpufreq_quick_get(unsigned int cpu)
 {
 	return 0;
 }
+static inline unsigned int cpufreq_quick_get_max(unsigned int cpu)
+{
+	return 0;
+}
 #endif