cpufreq: brcmstb-avs-cpufreq: send S2_ENTER / S2_EXIT commands to AVS

On suspend we send AVS_CMD_S2_ENTER and on resume AVS_CMD_S2_EXIT.
These are best effort calls, so we don't check the return code or take
any action if either of the calls fails.
Signed-off-by: Markus Mayer <mmayer@broadcom.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

drivers/cpufreq/brcmstb-avs-cpufreq.c

@@ -506,7 +506,14 @@ static int brcm_avs_suspend(struct cpufreq_policy *policy)
 	 * AVS co-processor, not necessarily the P-state we are running at now.
 	 * So, we get the current P-state explicitly.
 	 */
-	return brcm_avs_get_pstate(priv, &priv->pmap.state);
+	ret = brcm_avs_get_pstate(priv, &priv->pmap.state);
+	if (ret)
+		return ret;
+
+	/* This is best effort. Nothing to do if it fails. */
+	(void)__issue_avs_command(priv, AVS_CMD_S2_ENTER, 0, 0, NULL);
+
+	return 0;
 }
 
 static int brcm_avs_resume(struct cpufreq_policy *policy)
@@ -514,6 +521,9 @@ static int brcm_avs_resume(struct cpufreq_policy *policy)
 	struct private_data *priv = policy->driver_data;
 	int ret;
 
+	/* This is best effort. Nothing to do if it fails. */
+	(void)__issue_avs_command(priv, AVS_CMD_S2_EXIT, 0, 0, NULL);
+
 	ret = brcm_avs_set_pmap(priv, &priv->pmap);
 	if (ret == -EEXIST) {
 		struct platform_device *pdev  = cpufreq_get_driver_data();