pmdomain: mediatek: Move ctl sequences out of power_on/off functions

In preparation to support power domains of new SoCs and the modem
power domains for both new and already supported chips, move the
generic control power sequences out of the scpsys_power_on() and
scpsys_power_off() and put them in new scpsys_ctl_pwrseq_on(),
scpsys_ctl_pewseq_off() functions.

Reviewed-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20250805074746.29457-7-angelogioacchino.delregno@collabora.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Author: AngeloGioacchino Del Regno

drivers/pmdomain/mediatek/mtk-pm-domains.c

@@ -244,11 +244,45 @@ static int scpsys_regulator_disable(struct regulator *supply)
 	return supply ? regulator_disable(supply) : 0;
 }
 
+static int scpsys_ctl_pwrseq_on(struct scpsys_domain *pd)
+{
+	struct scpsys *scpsys = pd->scpsys;
+	bool tmp;
+	int ret;
+
+	/* subsys power on */
+	regmap_set_bits(scpsys->base, pd->data->ctl_offs, PWR_ON_BIT);
+	regmap_set_bits(scpsys->base, pd->data->ctl_offs, PWR_ON_2ND_BIT);
+
+	/* wait until PWR_ACK = 1 */
+	ret = readx_poll_timeout(scpsys_domain_is_on, pd, tmp, tmp, MTK_POLL_DELAY_US,
+				 MTK_POLL_TIMEOUT);
+	if (ret < 0)
+		return ret;
+
+	regmap_clear_bits(scpsys->base, pd->data->ctl_offs, PWR_CLK_DIS_BIT);
+	regmap_clear_bits(scpsys->base, pd->data->ctl_offs, PWR_ISO_BIT);
+	regmap_set_bits(scpsys->base, pd->data->ctl_offs, PWR_RST_B_BIT);
+
+	return 0;
+}
+
+static void scpsys_ctl_pwrseq_off(struct scpsys_domain *pd)
+{
+	struct scpsys *scpsys = pd->scpsys;
+
+	/* subsys power off */
+	regmap_set_bits(scpsys->base, pd->data->ctl_offs, PWR_ISO_BIT);
+	regmap_set_bits(scpsys->base, pd->data->ctl_offs, PWR_CLK_DIS_BIT);
+	regmap_clear_bits(scpsys->base, pd->data->ctl_offs, PWR_RST_B_BIT);
+	regmap_clear_bits(scpsys->base, pd->data->ctl_offs, PWR_ON_2ND_BIT);
+	regmap_clear_bits(scpsys->base, pd->data->ctl_offs, PWR_ON_BIT);
+}
+
 static int scpsys_power_on(struct generic_pm_domain *genpd)
 {
 	struct scpsys_domain *pd = container_of(genpd, struct scpsys_domain, genpd);
 	struct scpsys *scpsys = pd->scpsys;
-	bool tmp;
 	int ret;
 
 	ret = scpsys_regulator_enable(pd->supply);
@@ -263,20 +297,10 @@ static int scpsys_power_on(struct generic_pm_domain *genpd)
 		regmap_clear_bits(scpsys->base, pd->data->ext_buck_iso_offs,
 				  pd->data->ext_buck_iso_mask);
 
-	/* subsys power on */
-	regmap_set_bits(scpsys->base, pd->data->ctl_offs, PWR_ON_BIT);
-	regmap_set_bits(scpsys->base, pd->data->ctl_offs, PWR_ON_2ND_BIT);
-
-	/* wait until PWR_ACK = 1 */
-	ret = readx_poll_timeout(scpsys_domain_is_on, pd, tmp, tmp, MTK_POLL_DELAY_US,
-				 MTK_POLL_TIMEOUT);
-	if (ret < 0)
+	ret = scpsys_ctl_pwrseq_on(pd);
+	if (ret)
 		goto err_pwr_ack;
 
-	regmap_clear_bits(scpsys->base, pd->data->ctl_offs, PWR_CLK_DIS_BIT);
-	regmap_clear_bits(scpsys->base, pd->data->ctl_offs, PWR_ISO_BIT);
-	regmap_set_bits(scpsys->base, pd->data->ctl_offs, PWR_RST_B_BIT);
-
 	/*
 	 * In few Mediatek platforms(e.g. MT6779), the bus protect policy is
 	 * stricter, which leads to bus protect release must be prior to bus
@@ -342,12 +366,7 @@ static int scpsys_power_off(struct generic_pm_domain *genpd)
 
 	clk_bulk_disable_unprepare(pd->num_subsys_clks, pd->subsys_clks);
 
-	/* subsys power off */
-	regmap_set_bits(scpsys->base, pd->data->ctl_offs, PWR_ISO_BIT);
-	regmap_set_bits(scpsys->base, pd->data->ctl_offs, PWR_CLK_DIS_BIT);
-	regmap_clear_bits(scpsys->base, pd->data->ctl_offs, PWR_RST_B_BIT);
-	regmap_clear_bits(scpsys->base, pd->data->ctl_offs, PWR_ON_2ND_BIT);
-	regmap_clear_bits(scpsys->base, pd->data->ctl_offs, PWR_ON_BIT);
+	scpsys_ctl_pwrseq_off(pd);
 
 	/* wait until PWR_ACK = 0 */
 	ret = readx_poll_timeout(scpsys_domain_is_on, pd, tmp, !tmp, MTK_POLL_DELAY_US,