linux-kernel - [PATCH 3/3] cpufreq: brcmstb-avs-cpufreq: send S2_ENTER / S2

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Message-Id: <20200528182014.20021-3-mmayer@broadcom.com>
Date:   Thu, 28 May 2020 11:20:14 -0700
From:   Markus Mayer <markus.mayer@...adcom.com>
To:     "Rafael J. Wysocki" <rjw@...ysocki.net>,
        Viresh Kumar <viresh.kumar@...aro.org>,
        Florian Fainelli <f.fainelli@...il.com>
Cc:     Markus Mayer <markus.mayer@...adcom.com>,
        Linux Power Management List <linux-pm@...r.kernel.org>,
        Broadcom Kernel List <bcm-kernel-feedback-list@...adcom.com>,
        ARM Kernel List <linux-arm-kernel@...ts.infradead.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: [PATCH 3/3] 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@...adcom.com>
---
 drivers/cpufreq/brcmstb-avs-cpufreq.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/cpufreq/brcmstb-avs-cpufreq.c b/drivers/cpufreq/brcmstb-avs-cpufreq.c
index 79a0538a531a..3e31e5d28b79 100644
--- a/drivers/cpufreq/brcmstb-avs-cpufreq.c
+++ b/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();
-- 
2.17.1