[PATCH V4 7/8] genpd: imx: scu-pd: add multi states support

[Peng Fan (OSS)]

From: Peng Fan <peng.fan@xxxxxxx>

Add multi states support, this is to support devices could run in LP mode
when runtime suspend, and OFF mode when system suspend.

Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
---
 drivers/genpd/imx/scu-pd.c | 48 ++++++++++++++++++++++++++++++++++++--
 1 file changed, 46 insertions(+), 2 deletions(-)

diff --git a/drivers/genpd/imx/scu-pd.c b/drivers/genpd/imx/scu-pd.c
index 2f693b67ddb4..30da101119eb 100644
--- a/drivers/genpd/imx/scu-pd.c
+++ b/drivers/genpd/imx/scu-pd.c
@@ -65,6 +65,12 @@
 #include <linux/pm_domain.h>
 #include <linux/slab.h>
 
+enum {
+	PD_STATE_LP,
+	PD_STATE_OFF,
+	PD_STATE_MAX
+};
+
 /* SCU Power Mode Protocol definition */
 struct imx_sc_msg_req_set_resource_power_mode {
 	struct imx_sc_rpc_msg hdr;
@@ -368,7 +374,8 @@ static int imx_sc_pd_power(struct generic_pm_domain *domain, bool power_on)
 	hdr->size = 2;
 
 	msg.resource = pd->rsrc;
-	msg.mode = power_on ? IMX_SC_PM_PW_MODE_ON : IMX_SC_PM_PW_MODE_LP;
+	msg.mode = power_on ? IMX_SC_PM_PW_MODE_ON : pd->pd.state_idx ?
+		   IMX_SC_PM_PW_MODE_OFF : IMX_SC_PM_PW_MODE_LP;
 
 	/* keep uart console power on for no_console_suspend */
 	if (imx_con_rsrc == pd->rsrc && !console_suspend_enabled && !power_on)
@@ -412,11 +419,33 @@ static struct generic_pm_domain *imx_scu_pd_xlate(struct of_phandle_args *spec,
 	return domain;
 }
 
+static bool imx_sc_pd_suspend_ok(struct device *dev)
+{
+	/* Always true */
+	return true;
+}
+
+static bool imx_sc_pd_power_down_ok(struct dev_pm_domain *pd)
+{
+	struct generic_pm_domain *genpd = pd_to_genpd(pd);
+
+	/* For runtime suspend, choose LP mode */
+	genpd->state_idx = 0;
+
+	return true;
+}
+
+struct dev_power_governor imx_sc_pd_qos_governor = {
+	.suspend_ok = imx_sc_pd_suspend_ok,
+	.power_down_ok = imx_sc_pd_power_down_ok,
+};
+
 static struct imx_sc_pm_domain *
 imx_scu_add_pm_domain(struct device *dev, int idx,
 		      const struct imx_sc_pd_range *pd_ranges)
 {
 	struct imx_sc_pm_domain *sc_pd;
+	struct genpd_power_state *states;
 	bool is_off;
 	int mode, ret;
 
@@ -427,9 +456,22 @@ imx_scu_add_pm_domain(struct device *dev, int idx,
 	if (!sc_pd)
 		return ERR_PTR(-ENOMEM);
 
+	states = devm_kcalloc(dev, PD_STATE_MAX, sizeof(*states), GFP_KERNEL);
+	if (!states) {
+		devm_kfree(dev, sc_pd);
+		return ERR_PTR(-ENOMEM);
+	}
+
 	sc_pd->rsrc = pd_ranges->rsrc + idx;
 	sc_pd->pd.power_off = imx_sc_pd_power_off;
 	sc_pd->pd.power_on = imx_sc_pd_power_on;
+	states[PD_STATE_LP].power_off_latency_ns = 25000;
+	states[PD_STATE_LP].power_on_latency_ns =  25000;
+	states[PD_STATE_OFF].power_off_latency_ns = 2500000;
+	states[PD_STATE_OFF].power_on_latency_ns =  2500000;
+
+	sc_pd->pd.states = states;
+	sc_pd->pd.state_count = PD_STATE_MAX;
 
 	if (pd_ranges->postfix)
 		snprintf(sc_pd->name, sizeof(sc_pd->name),
@@ -455,14 +497,16 @@ imx_scu_add_pm_domain(struct device *dev, int idx,
 			 sc_pd->name, sc_pd->rsrc);
 
 		devm_kfree(dev, sc_pd);
+		devm_kfree(dev, states);
 		return NULL;
 	}
 
-	ret = pm_genpd_init(&sc_pd->pd, NULL, is_off);
+	ret = pm_genpd_init(&sc_pd->pd, &imx_sc_pd_qos_governor, is_off);
 	if (ret) {
 		dev_warn(dev, "failed to init pd %s rsrc id %d",
 			 sc_pd->name, sc_pd->rsrc);
 		devm_kfree(dev, sc_pd);
+		devm_kfree(dev, states);
 		return NULL;
 	}
 
-- 
2.37.1