soc: rockchip: io-domain: add rk3568 support

The io-domain registers on RK3568 SoCs have three separated bits to
enable/disable the 1.8v/2.5v/3.3v power.

This patch make the write to be a operation, allow rk3568 uses a private
register set function.

Since the 2.5v mode hasn't been fully validated yet, the driver only sets
1.8v [enable] + 3.3v [disable] for 1.8v mode
1.8v [disable] + 3.3v [enable] for 3.3v mode

There is not register order requirement which has been cleared by our IC
team.

For future reference the full usage matrix including the 2.5V setting is:
case  V33  V25  V18  result
0     0    0    0    IO safe, but cannot work
1     0    0    1    IO require 1.8V, should < 1.98V, otherwise IO may damage
2     0    1    0    IO require 2.5V, should < 2.75V, otherwise IO may damage
3     0    1    1    Invalid state, should avoid
4     1    0    0    IO require 3.3V, should < 3.63V, otherwise IO may damage
5     1    0    1    IO require 1.8V, should < 1.98V, otherwise IO may damage
6     1    1    0    IO require 2.5V, should < 2.75V, otherwise IO may damage
7     1    1    1    Invalid state, should avoid

Signed-off-by: Jianqun Xu <jay.xu@rock-chips.com>
Tested-by: Peter Geis <pgwipeout@gmail.com>
[added mode clarification from Jay]
Link: https://lore.kernel.org/r/20210805120107.27007-3-michael.riesch@wolfvision.net
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

Author: jayxurockchip

drivers/soc/rockchip/io-domain.c

@@ -51,13 +51,11 @@
 #define RK3399_PMUGRF_CON0_VSEL		BIT(8)
 #define RK3399_PMUGRF_VSEL_SUPPLY_NUM	9
 
-struct rockchip_iodomain;
+#define RK3568_PMU_GRF_IO_VSEL0		(0x0140)
+#define RK3568_PMU_GRF_IO_VSEL1		(0x0144)
+#define RK3568_PMU_GRF_IO_VSEL2		(0x0148)
 
-struct rockchip_iodomain_soc_data {
-	int grf_offset;
-	const char *supply_names[MAX_SUPPLIES];
-	void (*init)(struct rockchip_iodomain *iod);
-};
+struct rockchip_iodomain;
 
 struct rockchip_iodomain_supply {
 	struct rockchip_iodomain *iod;
@@ -66,13 +64,62 @@ struct rockchip_iodomain_supply {
 	int idx;
 };
 
+struct rockchip_iodomain_soc_data {
+	int grf_offset;
+	const char *supply_names[MAX_SUPPLIES];
+	void (*init)(struct rockchip_iodomain *iod);
+	int (*write)(struct rockchip_iodomain_supply *supply, int uV);
+};
+
 struct rockchip_iodomain {
 	struct device *dev;
 	struct regmap *grf;
 	const struct rockchip_iodomain_soc_data *soc_data;
 	struct rockchip_iodomain_supply supplies[MAX_SUPPLIES];
+	int (*write)(struct rockchip_iodomain_supply *supply, int uV);
 };
 
+static int rk3568_iodomain_write(struct rockchip_iodomain_supply *supply, int uV)
+{
+	struct rockchip_iodomain *iod = supply->iod;
+	u32 is_3v3 = uV > MAX_VOLTAGE_1_8;
+	u32 val0, val1;
+	int b;
+
+	switch (supply->idx) {
+	case 0: /* pmuio1 */
+		break;
+	case 1: /* pmuio2 */
+		b = supply->idx;
+		val0 = BIT(16 + b) | (is_3v3 ? 0 : BIT(b));
+		b = supply->idx + 4;
+		val1 = BIT(16 + b) | (is_3v3 ? BIT(b) : 0);
+
+		regmap_write(iod->grf, RK3568_PMU_GRF_IO_VSEL2, val0);
+		regmap_write(iod->grf, RK3568_PMU_GRF_IO_VSEL2, val1);
+		break;
+	case 3: /* vccio2 */
+		break;
+	case 2: /* vccio1 */
+	case 4: /* vccio3 */
+	case 5: /* vccio4 */
+	case 6: /* vccio5 */
+	case 7: /* vccio6 */
+	case 8: /* vccio7 */
+		b = supply->idx - 1;
+		val0 = BIT(16 + b) | (is_3v3 ? 0 : BIT(b));
+		val1 = BIT(16 + b) | (is_3v3 ? BIT(b) : 0);
+
+		regmap_write(iod->grf, RK3568_PMU_GRF_IO_VSEL0, val0);
+		regmap_write(iod->grf, RK3568_PMU_GRF_IO_VSEL1, val1);
+		break;
+	default:
+		return -EINVAL;
+	};
+
+	return 0;
+}
+
 static int rockchip_iodomain_write(struct rockchip_iodomain_supply *supply,
 				   int uV)
 {
@@ -136,7 +183,7 @@ static int rockchip_iodomain_notify(struct notifier_block *nb,
 			return NOTIFY_BAD;
 	}
 
-	ret = rockchip_iodomain_write(supply, uV);
+	ret = supply->iod->write(supply, uV);
 	if (ret && event == REGULATOR_EVENT_PRE_VOLTAGE_CHANGE)
 		return NOTIFY_BAD;
 
@@ -398,6 +445,22 @@ static const struct rockchip_iodomain_soc_data soc_data_rk3399_pmu = {
 	.init = rk3399_pmu_iodomain_init,
 };
 
+static const struct rockchip_iodomain_soc_data soc_data_rk3568_pmu = {
+	.grf_offset = 0x140,
+	.supply_names = {
+		"pmuio1",
+		"pmuio2",
+		"vccio1",
+		"vccio2",
+		"vccio3",
+		"vccio4",
+		"vccio5",
+		"vccio6",
+		"vccio7",
+	},
+	.write = rk3568_iodomain_write,
+};
+
 static const struct rockchip_iodomain_soc_data soc_data_rv1108 = {
 	.grf_offset = 0x404,
 	.supply_names = {
@@ -469,6 +532,10 @@ static const struct of_device_id rockchip_iodomain_match[] = {
 		.compatible = "rockchip,rk3399-pmu-io-voltage-domain",
 		.data = &soc_data_rk3399_pmu
 	},
+	{
+		.compatible = "rockchip,rk3568-pmu-io-voltage-domain",
+		.data = &soc_data_rk3568_pmu
+	},
 	{
 		.compatible = "rockchip,rv1108-io-voltage-domain",
 		.data = &soc_data_rv1108
@@ -502,6 +569,11 @@ static int rockchip_iodomain_probe(struct platform_device *pdev)
 	match = of_match_node(rockchip_iodomain_match, np);
 	iod->soc_data = match->data;
 
+	if (iod->soc_data->write)
+		iod->write = iod->soc_data->write;
+	else
+		iod->write = rockchip_iodomain_write;
+
 	parent = pdev->dev.parent;
 	if (parent && parent->of_node) {
 		iod->grf = syscon_node_to_regmap(parent->of_node);
@@ -562,7 +634,7 @@ static int rockchip_iodomain_probe(struct platform_device *pdev)
 		supply->reg = reg;
 		supply->nb.notifier_call = rockchip_iodomain_notify;
 
-		ret = rockchip_iodomain_write(supply, uV);
+		ret = iod->write(supply, uV);
 		if (ret) {
 			supply->reg = NULL;
 			goto unreg_notify;