[PATCH v7 7/8] devfreq: mediatek: cci devfreq register opp notification for SVS support

[Andrew-sh.Cheng]

From: "Andrew-sh.Cheng" <andrew-sh.cheng at mediatek.com>

SVS will change the voltage of opp item.
CCI devfreq need to react to change frequency.

Change-Id: I9d2ea9bd4be85970333eac92ab6fc330766e88da
Signed-off-by: Andrew-sh.Cheng <andrew-sh.cheng at mediatek.com>
---
 drivers/devfreq/mt8183-cci-devfreq.c | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/drivers/devfreq/mt8183-cci-devfreq.c b/drivers/devfreq/mt8183-cci-devfreq.c
index 62d02464a34b..9ccc49ba0b9a 100644
--- a/drivers/devfreq/mt8183-cci-devfreq.c
+++ b/drivers/devfreq/mt8183-cci-devfreq.c
@@ -21,6 +21,7 @@ struct cci_devfreq {
 	struct clk *cci_clk;
 	int old_vproc;
 	unsigned long old_freq;
+	struct notifier_block opp_nb;
 };
 
 static int mtk_cci_set_voltage(struct cci_devfreq *cci_df, int vproc)
@@ -89,6 +90,26 @@ static int mtk_cci_devfreq_target(struct device *dev, unsigned long *freq,
 	return 0;
 }
 
+static int ccidevfreq_opp_notifier(struct notifier_block *nb,
+				   unsigned long event, void *data)
+{
+	struct dev_pm_opp *opp = data;
+	struct cci_devfreq *cci_df = container_of(nb, struct cci_devfreq,
+						  opp_nb);
+	unsigned long	freq, volt;
+
+	if (event == OPP_EVENT_ADJUST_VOLTAGE) {
+		freq = dev_pm_opp_get_freq(opp);
+		/* current opp item is changed */
+		if (freq == cci_df->old_freq) {
+			volt = dev_pm_opp_get_voltage(opp);
+			mtk_cci_set_voltage(cci_df, volt);
+		}
+	}
+
+	return 0;
+}
+
 static struct devfreq_dev_profile cci_devfreq_profile = {
 	.target = mtk_cci_devfreq_target,
 };
@@ -98,12 +119,15 @@ static int mtk_cci_devfreq_probe(struct platform_device *pdev)
 	struct device *cci_dev = &pdev->dev;
 	struct cci_devfreq *cci_df;
 	struct devfreq_passive_data *passive_data;
+	struct notifier_block *opp_nb;
 	int ret;
 
 	cci_df = devm_kzalloc(cci_dev, sizeof(*cci_df), GFP_KERNEL);
 	if (!cci_df)
 		return -ENOMEM;
 
+	opp_nb = &cci_df->opp_nb;
+
 	cci_df->cci_clk = devm_clk_get(cci_dev, "cci_clock");
 	ret = PTR_ERR_OR_ZERO(cci_df->cci_clk);
 	if (ret) {
@@ -152,6 +176,9 @@ static int mtk_cci_devfreq_probe(struct platform_device *pdev)
 		goto err_opp;
 	}
 
+	opp_nb->notifier_call = ccidevfreq_opp_notifier;
+	dev_pm_opp_register_notifier(cci_dev, opp_nb);
+
 	return 0;
 
 err_opp:
-- 
2.12.5