regulator: act8945a-regulator: Implement PM functionalities

The regulator supports a dedicated suspend mode.
Implement the appropriate ->set_suspend_xx() hooks, add support for
->set_mode(), and provide basic PM ops functionalities to setup the
regulator in a suspend state when the system is entering suspend.

Signed-off-by: Boris Brezillon <[e-mail]>
[[e-mail]: remove shutdown function, use dev_pm_ops,
fix checkpatch warning, adapt commit message, add LDO modes support,
move modes constants to active-semi,8945a-regulator.h, remove rdevs from
struct act8945a_pmic, add op_mode to act8945a_pmic]
Signed-off-by: Claudiu Beznea <[e-mail]>
Signed-off-by: Mark Brown <[e-mail]>

drivers/regulator/act8945a-regulator.c

···
 #include <linux/regmap.h>
 #include <linux/regulator/driver.h>
 #include <linux/regulator/machine.h>
+#include <dt-bindings/regulator/active-semi,8945a-regulator.h>
 
 /**
  * ACT8945A Global Register Map.
···
 #define ACT8945A_DCDC1_VSET1	0x20
 #define ACT8945A_DCDC1_VSET2	0x21
 #define ACT8945A_DCDC1_CTRL	0x22
+#define ACT8945A_DCDC1_SUS	0x24
 #define ACT8945A_DCDC2_VSET1	0x30
 #define ACT8945A_DCDC2_VSET2	0x31
 #define ACT8945A_DCDC2_CTRL	0x32
+#define ACT8945A_DCDC2_SUS	0x34
 #define ACT8945A_DCDC3_VSET1	0x40
 #define ACT8945A_DCDC3_VSET2	0x41
 #define ACT8945A_DCDC3_CTRL	0x42
+#define ACT8945A_DCDC3_SUS	0x44
 #define ACT8945A_LDO1_VSET	0x50
 #define ACT8945A_LDO1_CTRL	0x51
+#define ACT8945A_LDO1_SUS	0x52
 #define ACT8945A_LDO2_VSET	0x54
 #define ACT8945A_LDO2_CTRL	0x55
+#define ACT8945A_LDO2_SUS	0x56
 #define ACT8945A_LDO3_VSET	0x60
 #define ACT8945A_LDO3_CTRL	0x61
+#define ACT8945A_LDO3_SUS	0x62
 #define ACT8945A_LDO4_VSET	0x64
 #define ACT8945A_LDO4_CTRL	0x65
+#define ACT8945A_LDO4_SUS	0x66
 
 /**
  * Field Definitions.
···
 	ACT8945A_ID_LDO2,
 	ACT8945A_ID_LDO3,
 	ACT8945A_ID_LDO4,
-	ACT8945A_REG_NUM,
+	ACT8945A_ID_MAX,
+};
+
+struct act8945a_pmic {
+	struct regmap *regmap;
+	u32 op_mode[ACT8945A_ID_MAX];
 };
 
 static const struct regulator_linear_range act8945a_voltage_ranges[] = {
···
 	REGULATOR_LINEAR_RANGE(2400000, 48, 63, 100000),
 };
 
+static int act8945a_set_suspend_state(struct regulator_dev *rdev, bool enable)
+{
+	struct regmap *regmap = rdev->regmap;
+	int id = rdev->desc->id, reg, val;
+
+	switch (id) {
+	case ACT8945A_ID_DCDC1:
+		reg = ACT8945A_DCDC1_SUS;
+		val = 0xa8;
+		break;
+	case ACT8945A_ID_DCDC2:
+		reg = ACT8945A_DCDC2_SUS;
+		val = 0xa8;
+		break;
+	case ACT8945A_ID_DCDC3:
+		reg = ACT8945A_DCDC3_SUS;
+		val = 0xa8;
+		break;
+	case ACT8945A_ID_LDO1:
+		reg = ACT8945A_LDO1_SUS;
+		val = 0xe8;
+		break;
+	case ACT8945A_ID_LDO2:
+		reg = ACT8945A_LDO2_SUS;
+		val = 0xe8;
+		break;
+	case ACT8945A_ID_LDO3:
+		reg = ACT8945A_LDO3_SUS;
+		val = 0xe8;
+		break;
+	case ACT8945A_ID_LDO4:
+		reg = ACT8945A_LDO4_SUS;
+		val = 0xe8;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (enable)
+		val |= BIT(4);
+
+	/*
+	 * Ask the PMIC to enable/disable this output when entering hibernate
+	 * mode.
+	 */
+	return regmap_write(regmap, reg, val);
+}
+
+static int act8945a_set_suspend_enable(struct regulator_dev *rdev)
+{
+	return act8945a_set_suspend_state(rdev, true);
+}
+
+static int act8945a_set_suspend_disable(struct regulator_dev *rdev)
+{
+	return act8945a_set_suspend_state(rdev, false);
+}
+
+static unsigned int act8945a_of_map_mode(unsigned int mode)
+{
+	switch (mode) {
+	case ACT8945A_REGULATOR_MODE_FIXED:
+	case ACT8945A_REGULATOR_MODE_NORMAL:
+		return REGULATOR_MODE_NORMAL;
+	case ACT8945A_REGULATOR_MODE_LOWPOWER:
+		return REGULATOR_MODE_STANDBY;
+	default:
+		return REGULATOR_MODE_INVALID;
+	}
+}
+
+static int act8945a_set_mode(struct regulator_dev *rdev, unsigned int mode)
+{
+	struct act8945a_pmic *act8945a = rdev_get_drvdata(rdev);
+	struct regmap *regmap = rdev->regmap;
+	int id = rdev->desc->id;
+	int reg, ret, val = 0;
+
+	switch (id) {
+	case ACT8945A_ID_DCDC1:
+		reg = ACT8945A_DCDC1_CTRL;
+		break;
+	case ACT8945A_ID_DCDC2:
+		reg = ACT8945A_DCDC2_CTRL;
+		break;
+	case ACT8945A_ID_DCDC3:
+		reg = ACT8945A_DCDC3_CTRL;
+		break;
+	case ACT8945A_ID_LDO1:
+		reg = ACT8945A_LDO1_SUS;
+		break;
+	case ACT8945A_ID_LDO2:
+		reg = ACT8945A_LDO2_SUS;
+		break;
+	case ACT8945A_ID_LDO3:
+		reg = ACT8945A_LDO3_SUS;
+		break;
+	case ACT8945A_ID_LDO4:
+		reg = ACT8945A_LDO4_SUS;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	switch (mode) {
+	case REGULATOR_MODE_STANDBY:
+		if (rdev->desc->id > ACT8945A_ID_DCDC3)
+			val = BIT(5);
+		break;
+	case REGULATOR_MODE_NORMAL:
+		if (rdev->desc->id <= ACT8945A_ID_DCDC3)
+			val = BIT(5);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	ret = regmap_update_bits(regmap, reg, BIT(5), val);
+	if (ret)
+		return ret;
+
+	act8945a->op_mode[id] = mode;
+
+	return 0;
+}
+
+static unsigned int act8945a_get_mode(struct regulator_dev *rdev)
+{
+	struct act8945a_pmic *act8945a = rdev_get_drvdata(rdev);
+	int id = rdev->desc->id;
+
+	if (id < ACT8945A_ID_DCDC1 || id >= ACT8945A_ID_MAX)
+		return -EINVAL;
+
+	return act8945a->op_mode[id];
+}
+
 static const struct regulator_ops act8945a_ops = {
 	.list_voltage		= regulator_list_voltage_linear_range,
 	.map_voltage		= regulator_map_voltage_linear_range,
···
 	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
 	.enable			= regulator_enable_regmap,
 	.disable		= regulator_disable_regmap,
+	.set_mode		= act8945a_set_mode,
+	.get_mode		= act8945a_get_mode,
 	.is_enabled		= regulator_is_enabled_regmap,
+	.set_suspend_enable	= act8945a_set_suspend_enable,
+	.set_suspend_disable	= act8945a_set_suspend_disable,
 };
 
 #define ACT89xx_REG(_name, _family, _id, _vsel_reg, _supply)		\
···
 		.name			= _name,			\
 		.supply_name		= _supply,			\
 		.of_match		= of_match_ptr("REG_"#_id),	\
+		.of_map_mode		= act8945a_of_map_mode,		\
 		.regulators_node	= of_match_ptr("regulators"),	\
 		.id			= _family##_ID_##_id,		\
 		.type			= REGULATOR_VOLTAGE,		\
···
 {
 	struct regulator_config config = { };
 	const struct regulator_desc *regulators;
+	struct act8945a_pmic *act8945a;
 	struct regulator_dev *rdev;
-	struct regmap *regmap;
 	int i, num_regulators;
 	bool voltage_select;
 
-	regmap = dev_get_regmap(pdev->dev.parent, NULL);
-	if (!regmap) {
+	act8945a = devm_kzalloc(&pdev->dev, sizeof(*act8945a), GFP_KERNEL);
+	if (!act8945a)
+		return -ENOMEM;
+
+	act8945a->regmap = dev_get_regmap(pdev->dev.parent, NULL);
+	if (!act8945a->regmap) {
 		dev_err(&pdev->dev,
 			"could not retrieve regmap from parent device\n");
 		return -EINVAL;
···
 
 	config.dev = &pdev->dev;
 	config.dev->of_node = pdev->dev.parent->of_node;
+	config.driver_data = act8945a;
 	for (i = 0; i < num_regulators; i++) {
 		rdev = devm_regulator_register(&pdev->dev, &regulators[i], &config);
 		if (IS_ERR(rdev)) {
···
 		}
 	}
 
+	platform_set_drvdata(pdev, act8945a);
+
 	/* Unlock expert registers. */
-	return regmap_write(regmap, ACT8945A_SYS_UNLK_REGS, 0xef);
+	return regmap_write(act8945a->regmap, ACT8945A_SYS_UNLK_REGS, 0xef);
 }
+
+static int act8945a_suspend(struct device *pdev)
+{
+	struct act8945a_pmic *act8945a = dev_get_drvdata(pdev);
+
+	/*
+	 * Ask the PMIC to enter the suspend mode on the next PWRHLD
+	 * transition.
+	 */
+	return regmap_write(act8945a->regmap, ACT8945A_SYS_CTRL, 0x42);
+}
+
+SIMPLE_DEV_PM_OPS(act8945a_pm, act8945a_suspend, NULL);
 
 static struct platform_driver act8945a_pmic_driver = {
 	.driver = {
 		.name = "act8945a-regulator",
+		.pm = &act8945a_pm,
 	},
 	.probe = act8945a_pmic_probe,
 };

include/dt-bindings/regulator/active-semi,8945a-regulator.h

···
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2018 Microchip Technology, Inc. All rights reserved.
+ *
+ * Device Tree binding constants for the ACT8945A PMIC regulators
+ */
+
+#ifndef _DT_BINDINGS_REGULATOR_ACT8945A_H
+#define _DT_BINDINGS_REGULATOR_ACT8945A_H
+
+/*
+ * These constants should be used to specify regulator modes in device tree for
+ * ACT8945A regulators as follows:
+ * ACT8945A_REGULATOR_MODE_FIXED:	It is specific to DCDC regulators and it
+ *					specifies the usage of fixed-frequency
+ *					PWM.
+ *
+ * ACT8945A_REGULATOR_MODE_NORMAL:	It is specific to LDO regulators and it
+ *					specifies the usage of normal mode.
+ *
+ * ACT8945A_REGULATOR_MODE_LOWPOWER:	For DCDC and LDO regulators; it specify
+ *					the usage of proprietary power-saving
+ *					mode.
+ */
+
+#define ACT8945A_REGULATOR_MODE_FIXED		1
+#define ACT8945A_REGULATOR_MODE_NORMAL		2
+#define ACT8945A_REGULATOR_MODE_LOWPOWER	3
+
+#endif