soc: mediatek: Refactor bus protection control

Put bus protection enable and disable control in separate functions.

Signed-off-by: Weiyi Lu <[e-mail]>
Signed-off-by: Matthias Brugger <[e-mail]>

drivers/soc/mediatek/mtk-scpsys.c

···
 			MTK_POLL_DELAY_US, MTK_POLL_TIMEOUT);
 }
 
+static int scpsys_bus_protect_enable(struct scp_domain *scpd)
+{
+	struct scp *scp = scpd->scp;
+
+	if (!scpd->data->bus_prot_mask)
+		return 0;
+
+	return mtk_infracfg_set_bus_protection(scp->infracfg,
+			scpd->data->bus_prot_mask,
+			scp->bus_prot_reg_update);
+}
+
+static int scpsys_bus_protect_disable(struct scp_domain *scpd)
+{
+	struct scp *scp = scpd->scp;
+
+	if (!scpd->data->bus_prot_mask)
+		return 0;
+
+	return mtk_infracfg_clear_bus_protection(scp->infracfg,
+			scpd->data->bus_prot_mask,
+			scp->bus_prot_reg_update);
+}
+
 static int scpsys_power_on(struct generic_pm_domain *genpd)
 {
 	struct scp_domain *scpd = container_of(genpd, struct scp_domain, genpd);
···
 	if (ret < 0)
 		goto err_pwr_ack;
 
-	if (scpd->data->bus_prot_mask) {
-		ret = mtk_infracfg_clear_bus_protection(scp->infracfg,
-				scpd->data->bus_prot_mask,
-				scp->bus_prot_reg_update);
-		if (ret)
-			goto err_pwr_ack;
-	}
+	ret = scpsys_bus_protect_disable(scpd);
+	if (ret < 0)
+		goto err_pwr_ack;
 
 	return 0;
 
···
 	u32 val;
 	int ret, tmp;
 
-	if (scpd->data->bus_prot_mask) {
-		ret = mtk_infracfg_set_bus_protection(scp->infracfg,
-				scpd->data->bus_prot_mask,
-				scp->bus_prot_reg_update);
-		if (ret)
-			goto out;
-	}
+	ret = scpsys_bus_protect_enable(scpd);
+	if (ret < 0)
+		goto out;
 
 	ret = scpsys_sram_disable(scpd, ctl_addr);
 	if (ret < 0)