cpufreq: introduce cpufreq_generic_get() routine

CPUFreq drivers that use clock frameworks interface,i.e. clk_get_rate(),
to get CPUs clk rate, have similar sort of code used in most of them.

This patch adds a generic ->get() which will do the same thing for them.
All those drivers are required to now is to set .get to cpufreq_generic_get()
and set their clk pointer in policy->clk during ->init().

Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/cpufreq/davinci-cpufreq.c b/drivers/cpufreq/davinci-cpufreq.c
index 04f3390..2cf3384 100644
--- a/drivers/cpufreq/davinci-cpufreq.c
+++ b/drivers/cpufreq/davinci-cpufreq.c
@@ -58,14 +58,6 @@
 	return 0;
 }
 
-static unsigned int davinci_getspeed(unsigned int cpu)
-{
-	if (cpu)
-		return 0;
-
-	return clk_get_rate(cpufreq.armclk) / 1000;
-}
-
 static int davinci_target(struct cpufreq_policy *policy, unsigned int idx)
 {
 	struct davinci_cpufreq_config *pdata = cpufreq.dev->platform_data;
@@ -73,7 +65,7 @@
 	unsigned int old_freq, new_freq;
 	int ret = 0;
 
-	old_freq = davinci_getspeed(0);
+	old_freq = policy->cur;
 	new_freq = pdata->freq_table[idx].frequency;
 
 	/* if moving to higher frequency, up the voltage beforehand */
@@ -116,6 +108,8 @@
 			return result;
 	}
 
+	policy->clk = cpufreq.armclk;
+
 	/*
 	 * Time measurement across the target() function yields ~1500-1800us
 	 * time taken with no drivers on notification list.
@@ -129,7 +123,7 @@
 	.flags		= CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK,
 	.verify		= davinci_verify_speed,
 	.target_index	= davinci_target,
-	.get		= davinci_getspeed,
+	.get		= cpufreq_generic_get,
 	.init		= davinci_cpu_init,
 	.exit		= cpufreq_generic_exit,
 	.name		= "davinci",