[PATCH v4 0/4] Add regulator support for mpq7920

[PATCH v4 0/4] Add regulator support for mpq7920

[Saravanan Sekar]

Changes in V4:
    - fixed 0-DAY warnings

Changes in V3:
    - fixed review comments in Documentation and dt_bindings_check passed 

Changes in V2:
    - fixed all the review comments in the driver, avoid ternery operator, inline & constant
    - fixed/modifed review comments in Documentation

This patch series add support for PMIC regulator driver for Monolithic
Power System's MPQ7920 chipset. MPQ7920 provides support for 4-BUCK converter,
one fixed voltage RTCLDO and 4-LDO regualtor, accessed over I2C.

Saravanan Sekar (4):
  dt-bindings: Add an entry for Monolithic Power System, MPS
  dt-bindings: regulator: add document bindings for mpq7920
  regulator: mpq7920: add mpq7920 regulator driver
  MAINTAINERS: Add entry for mpq7920 PMIC driver

 .../bindings/regulator/mpq7920.yaml           | 143 +++++++
 .../devicetree/bindings/vendor-prefixes.yaml  |   2 +
 MAINTAINERS                                   |   7 +
 drivers/regulator/Kconfig                     |  10 +
 drivers/regulator/Makefile                    |   1 +
 drivers/regulator/mpq7920.c                   | 392 ++++++++++++++++++
 drivers/regulator/mpq7920.h                   |  72 ++++
 7 files changed, 627 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/regulator/mpq7920.yaml
 create mode 100644 drivers/regulator/mpq7920.c
 create mode 100644 drivers/regulator/mpq7920.h

-- 
2.17.1

[PATCH v4 1/4] dt-bindings: Add an entry for Monolithic Power System, MPS

[Saravanan Sekar]

Add an entry for Monolithic Power System, MPS

Signed-off-by: Saravanan Sekar <sravanhome@gmail.com>
---
 Documentation/devicetree/bindings/vendor-prefixes.yaml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/vendor-prefixes.yaml b/Documentation/devicetree/bindings/vendor-prefixes.yaml
index 6046f4555852..5eac9d08bfa8 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.yaml
+++ b/Documentation/devicetree/bindings/vendor-prefixes.yaml
@@ -605,6 +605,8 @@ patternProperties:
     description: MiraMEMS Sensing Technology Co., Ltd.
   "^mitsubishi,.*":
     description: Mitsubishi Electric Corporation
+  "^mps,.*":
+    description: Monolithic Power Systems, Inc.
   "^mosaixtech,.*":
     description: Mosaix Technologies, Inc.
   "^motorola,.*":
-- 
2.17.1

[PATCH v4 2/4] dt-bindings: regulator: add document bindings for mpq7920

[Saravanan Sekar]

Add device tree binding information for mpq7920 regulator driver.
Example bindings for mpq7920 are added.

Signed-off-by: Saravanan Sekar <sravanhome@gmail.com>
---
 .../bindings/regulator/mpq7920.yaml           | 143 ++++++++++++++++++
 1 file changed, 143 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/regulator/mpq7920.yaml

diff --git a/Documentation/devicetree/bindings/regulator/mpq7920.yaml b/Documentation/devicetree/bindings/regulator/mpq7920.yaml
new file mode 100644
index 000000000000..54e9177dfd1b
--- /dev/null
+++ b/Documentation/devicetree/bindings/regulator/mpq7920.yaml
@@ -0,0 +1,143 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/regulator/mpq7920.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Monolithic Power System MPQ7920 PMIC
+
+maintainers:
+  - Saravanan Sekar <sravanhome@gmail.com>
+
+properties:
+  $nodename:
+    pattern: "pmic@[0-9a-f]{1,2}"
+  compatible:
+    enum:
+      - mps,mpq7920
+
+  reg:
+    maxItems: 1
+
+  mps,time-slot:
+    description:
+      each regulator output shall be delayed during power on/off sequence which
+      based on configurable time slot value, must be one of following corresponding
+      value 0.5ms, 2ms, 8ms, 16ms
+    allOf:
+      - $ref: "/schemas/types.yaml#/definitions/uint8"
+      - enum: [ 0, 1, 2, 3 ]
+      - default: 0
+
+  mps,fixed-on-time:
+     description:
+       select power on sequence with fixed time output delay mentioned in
+       time-slot reg for all the regulators.
+     type: boolean
+
+  mps,fixed-off-time:
+     description:
+        select power off sequence with fixed time output delay mentioned in
+        time-slot reg for all the regulators.
+     type: boolean
+
+  mps,inc-off-time:
+     description: |
+        mutually exclusive to mps,fixed-off-time an array of 8, linearly increase
+        output delay during power off sequence based on factor of time slot/interval
+        for each regulator.
+     allOf:
+       - $ref: "/schemas/types.yaml#/definitions/uint8-array"
+       - minimum: 0
+       - maximum: 15
+       - default: [ 0, 6, 0, 6, 7, 7, 7, 9 ]
+
+  mps,inc-on-time:
+     description: |
+        mutually exclusive to mps,fixed-on-time an array of 8, linearly increase
+        output delay during power on sequence based on factor of time slot/interval
+        for each regulator.
+     allOf:
+       - $ref: "/schemas/types.yaml#/definitions/uint8-array"
+       - minimum: 0
+       - maximum: 15
+       - default: [ 0, 6, 0, 6, 7, 7, 7, 9 ]
+
+  mps,switch-freq:
+     description: |
+        switching frequency must be one of following corresponding value
+        1.1MHz, 1.65MHz, 2.2MHz, 2.75MHz
+     allOf:
+       - $ref: "/schemas/types.yaml#/definitions/uint8"
+       - enum: [ 0, 1, 2, 3 ]
+       - default: 2
+
+  mps,buck-softstart:
+     description: |
+        An array of 4 contains soft start time of each buck, must be one of
+        following corresponding values 150us, 300us, 610us, 920us
+     allOf:
+       - $ref: "/schemas/types.yaml#/definitions/uint8-array"
+       - enum: [ 0, 1, 2, 3 ]
+       - default: [ 1, 1, 1, 1 ]
+
+  mps,buck-ovp:
+     description: |
+        An array of 4 contains over voltage protection of each buck, must be
+        one of above values
+     allOf:
+       - $ref: "/schemas/types.yaml#/definitions/uint8-array"
+       - enum: [ 0, 1 ]
+       - default: [ 1, 1, 1, 1 ]
+
+  mps,buck-phase-delay:
+     description: |
+        An array of 4 contains phase delay of each buck must be one of above values
+        corresponding to 0deg, 90deg, 180deg, 270deg
+     allOf:
+       - $ref: "/schemas/types.yaml#/definitions/uint8-array"
+       - enum: [ 0, 1, 2, 3 ]
+       - default: [ 0, 0, 1, 1 ]
+
+  regulators:
+    type: object
+    description:
+      list of regulators provided by this controller, must be named
+      after their hardware counterparts BUCK[1-4], one LDORTC, and LDO[2-5]
+      The valid names for regulators are
+      buck1, buck2, buck3, buck4, ldortc, ldo2, ldo3, ldo4, ldo5
+
+
+examples:
+  - |
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        pmic@69 {
+          compatible = "mps,mpq7920";
+          reg = <0x69>;
+
+          mps,switch-freq = <1>;
+          mps,buck-softstart = /bits/ 8 <1 2 1 3>;
+          mps,buck-ovp = /bits/ 8 <1 0 1 1>;
+
+          regulators {
+            buck1 {
+             regulator-name = "buck1";
+             regulator-min-microvolt = <400000>;
+             regulator-max-microvolt = <3587500>;
+             regulator-min-microamp  = <460000>;
+             regulator-max-microamp  = <7600000>;
+             regulator-boot-on;
+            };
+
+            ldo2 {
+             regulator-name = "ldo2";
+             regulator-min-microvolt = <650000>;
+             regulator-max-microvolt = <3587500>;
+            };
+         };
+       };
+     };
+...
-- 
2.17.1

[PATCH v4 3/4] regulator: mpq7920: add mpq7920 regulator driver

[Saravanan Sekar]

Adding regulator driver for the device mpq7920.
The MPQ7920 PMIC device contains four DC-DC buck converters and
five regulators, is designed for automotive and accessed over I2C.

Signed-off-by: Saravanan Sekar <sravanhome@gmail.com>
---
 drivers/regulator/Kconfig   |  10 +
 drivers/regulator/Makefile  |   1 +
 drivers/regulator/mpq7920.c | 392 ++++++++++++++++++++++++++++++++++++
 drivers/regulator/mpq7920.h |  72 +++++++
 4 files changed, 475 insertions(+)
 create mode 100644 drivers/regulator/mpq7920.c
 create mode 100644 drivers/regulator/mpq7920.h

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 74eb5af7295f..e10adc2e57da 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -600,6 +600,16 @@ config REGULATOR_MCP16502
 	  through the regulator interface. In addition it enables
 	  suspend-to-ram/standby transition.
 
+config REGULATOR_MPQ7920
+	tristate "Monolithic MPQ7920 PMIC"
+	depends on I2C && OF
+	select REGMAP_I2C
+	help
+	  Say y here to support the MPQ7920 PMIC. This will enable supports
+	  the software controllable 4 buck and 5 LDO regulators.
+	  This driver supports the control of different power rails of device
+	  through regulator interface.
+
 config REGULATOR_MT6311
 	tristate "MediaTek MT6311 PMIC"
 	depends on I2C
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index 2210ba56f9bd..fd11002507e4 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -77,6 +77,7 @@ obj-$(CONFIG_REGULATOR_MC13783) += mc13783-regulator.o
 obj-$(CONFIG_REGULATOR_MC13892) += mc13892-regulator.o
 obj-$(CONFIG_REGULATOR_MC13XXX_CORE) +=  mc13xxx-regulator-core.o
 obj-$(CONFIG_REGULATOR_MCP16502) += mcp16502.o
+obj-$(CONFIG_REGULATOR_MPQ7920) += mpq7920.o
 obj-$(CONFIG_REGULATOR_MT6311) += mt6311-regulator.o
 obj-$(CONFIG_REGULATOR_MT6323)	+= mt6323-regulator.o
 obj-$(CONFIG_REGULATOR_MT6358)	+= mt6358-regulator.o
diff --git a/drivers/regulator/mpq7920.c b/drivers/regulator/mpq7920.c
new file mode 100644
index 000000000000..5a86dd855b23
--- /dev/null
+++ b/drivers/regulator/mpq7920.c
@@ -0,0 +1,392 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// mpq7920.c  - regulator driver for mps mpq7920
+//
+// Copyright 2019 Monolithic Power Systems, Inc
+//
+// Author: Saravanan Sekar <sravanhome@gmail.com>
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/of_regulator.h>
+#include <linux/i2c.h>
+#include <linux/regmap.h>
+#include "mpq7920.h"
+
+#define MPQ7920_BUCK_VOLT_RANGE \
+	((MPQ7920_VOLT_MAX - MPQ7920_BUCK_VOLT_MIN)/MPQ7920_VOLT_STEP + 1)
+#define MPQ7920_LDO_VOLT_RANGE \
+	((MPQ7920_VOLT_MAX - MPQ7920_LDO_VOLT_MIN)/MPQ7920_VOLT_STEP + 1)
+
+#define MPQ7920BUCK(_name, _id, _ilim)					\
+	[MPQ7920_BUCK ## _id] = {					\
+		.id = MPQ7920_BUCK ## _id,				\
+		.name = _name,						\
+		.of_match = _name,					\
+		.regulators_node = "regulators",			\
+		.ops = &mpq7920_buck_ops,				\
+		.min_uV = MPQ7920_BUCK_VOLT_MIN,			\
+		.uV_step = MPQ7920_VOLT_STEP,				\
+		.n_voltages = MPQ7920_BUCK_VOLT_RANGE,			\
+		.curr_table = _ilim,					\
+		.n_current_limits = ARRAY_SIZE(_ilim),			\
+		.csel_reg = MPQ7920_BUCK ##_id## _REG_C,		\
+		.csel_mask = MPQ7920_MASK_BUCK_ILIM,			\
+		.enable_reg = MPQ7920_REG_REGULATOR_EN,			\
+		.enable_mask = BIT(MPQ7920_REGULATOR_EN_OFFSET -	\
+					 MPQ7920_BUCK ## _id),		\
+		.vsel_reg = MPQ7920_BUCK ##_id## _REG_A,		\
+		.vsel_mask = MPQ7920_MASK_VREF,				\
+		.active_discharge_on	= MPQ7920_DISCHARGE_ON,		\
+		.active_discharge_reg	= MPQ7920_BUCK ##_id## _REG_B,	\
+		.active_discharge_mask	= MPQ7920_MASK_DISCHARGE,	\
+		.soft_start_reg		= MPQ7920_BUCK ##_id## _REG_C,	\
+		.soft_start_mask	= MPQ7920_MASK_SOFTSTART,	\
+		.owner			= THIS_MODULE,			\
+	}
+
+#define MPQ7920LDO(_name, _id, _ops, _ilim, _ilim_sz, _creg, _cmask)	\
+	[MPQ7920_LDO ## _id] = {					\
+		.id = MPQ7920_LDO ## _id,				\
+		.name = _name,						\
+		.of_match = _name,					\
+		.regulators_node = "regulators",			\
+		.ops = _ops,						\
+		.min_uV = MPQ7920_LDO_VOLT_MIN,				\
+		.uV_step = MPQ7920_VOLT_STEP,				\
+		.n_voltages = MPQ7920_LDO_VOLT_RANGE,			\
+		.vsel_reg = MPQ7920_LDO ##_id## _REG_A,			\
+		.vsel_mask = MPQ7920_MASK_VREF,				\
+		.curr_table = _ilim,					\
+		.n_current_limits = _ilim_sz,				\
+		.csel_reg = _creg,					\
+		.csel_mask = _cmask,					\
+		.enable_reg = (_id == 1) ? 0 : MPQ7920_REG_REGULATOR_EN,\
+		.enable_mask = BIT(MPQ7920_REGULATOR_EN_OFFSET -	\
+					MPQ7920_LDO ##_id + 1),		\
+		.active_discharge_on	= MPQ7920_DISCHARGE_ON,		\
+		.active_discharge_mask	= MPQ7920_MASK_DISCHARGE,	\
+		.active_discharge_reg	= MPQ7920_LDO ##_id## _REG_B,	\
+		.type			= REGULATOR_VOLTAGE,		\
+		.owner			= THIS_MODULE,			\
+	}
+
+enum mpq7920_regulators {
+	MPQ7920_BUCK1,
+	MPQ7920_BUCK2,
+	MPQ7920_BUCK3,
+	MPQ7920_BUCK4,
+	MPQ7920_LDO1, /* LDORTC */
+	MPQ7920_LDO2,
+	MPQ7920_LDO3,
+	MPQ7920_LDO4,
+	MPQ7920_LDO5,
+	MPQ7920_MAX_REGULATORS,
+};
+
+struct mpq7920_regulator_info {
+	struct device *dev;
+	struct regmap *regmap;
+	struct regulator_dev *rdev[MPQ7920_MAX_REGULATORS];
+	struct regulator_desc *rdesc;
+};
+
+static const struct regmap_config mpq7920_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = 0x25,
+};
+
+/* Current limits array (in uA)
+ * ILIM1 & ILIM3
+ */
+static const unsigned int mpq7920_I_limits1[] = {
+	4600000, 6600000, 7600000, 9300000
+};
+
+/* ILIM2 & ILIM4 */
+static const unsigned int mpq7920_I_limits2[] = {
+	2700000, 3900000, 5100000, 6100000
+};
+
+/* LDO4 & LDO5 */
+static const unsigned int mpq7920_I_limits3[] = {
+	300000, 700000
+};
+
+static int mpq7920_set_ramp_delay(struct regulator_dev *rdev, int ramp_delay);
+
+/* RTCLDO not controllable, always ON */
+static const struct regulator_ops mpq7920_ldortc_ops = {
+	.list_voltage		= regulator_list_voltage_linear,
+	.map_voltage		= regulator_map_voltage_linear,
+	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
+	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
+};
+
+static const struct regulator_ops mpq7920_ldo_wo_current_ops = {
+	.enable			= regulator_enable_regmap,
+	.disable		= regulator_disable_regmap,
+	.is_enabled		= regulator_is_enabled_regmap,
+	.list_voltage		= regulator_list_voltage_linear,
+	.map_voltage		= regulator_map_voltage_linear,
+	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
+	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
+	.set_active_discharge	= regulator_set_active_discharge_regmap,
+};
+
+static const struct regulator_ops mpq7920_ldo_ops = {
+	.enable			= regulator_enable_regmap,
+	.disable		= regulator_disable_regmap,
+	.is_enabled		= regulator_is_enabled_regmap,
+	.list_voltage		= regulator_list_voltage_linear,
+	.map_voltage		= regulator_map_voltage_linear,
+	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
+	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
+	.set_active_discharge	= regulator_set_active_discharge_regmap,
+	.get_current_limit	= regulator_get_current_limit_regmap,
+	.set_current_limit	= regulator_set_current_limit_regmap,
+};
+
+static const struct regulator_ops mpq7920_buck_ops = {
+	.enable			= regulator_enable_regmap,
+	.disable		= regulator_disable_regmap,
+	.is_enabled		= regulator_is_enabled_regmap,
+	.list_voltage		= regulator_list_voltage_linear,
+	.map_voltage		= regulator_map_voltage_linear,
+	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
+	.set_voltage_sel	= regulator_set_voltage_sel_regmap,
+	.set_active_discharge	= regulator_set_active_discharge_regmap,
+	.set_soft_start		= regulator_set_soft_start_regmap,
+	.set_ramp_delay		= mpq7920_set_ramp_delay,
+};
+
+static struct regulator_desc mpq7920_regulators_desc[MPQ7920_MAX_REGULATORS] = {
+	MPQ7920BUCK("buck1", 1, mpq7920_I_limits1),
+	MPQ7920BUCK("buck2", 2, mpq7920_I_limits2),
+	MPQ7920BUCK("buck3", 3, mpq7920_I_limits1),
+	MPQ7920BUCK("buck4", 4, mpq7920_I_limits2),
+	MPQ7920LDO("ldortc", 1, &mpq7920_ldortc_ops, NULL, 0, 0, 0),
+	MPQ7920LDO("ldo2", 2, &mpq7920_ldo_wo_current_ops, NULL, 0, 0, 0),
+	MPQ7920LDO("ldo3", 3, &mpq7920_ldo_wo_current_ops, NULL, 0, 0, 0),
+	MPQ7920LDO("ldo4", 4, &mpq7920_ldo_ops, mpq7920_I_limits3,
+			ARRAY_SIZE(mpq7920_I_limits3), MPQ7920_LDO4_REG_B,
+			MPQ7920_MASK_LDO_ILIM),
+	MPQ7920LDO("ldo5", 5, &mpq7920_ldo_ops, mpq7920_I_limits3,
+			ARRAY_SIZE(mpq7920_I_limits3), MPQ7920_LDO5_REG_B,
+			MPQ7920_MASK_LDO_ILIM),
+};
+
+/*
+ * DVS ramp rate BUCK1 to BUCK4
+ * 00-01: Reserved
+ * 10: 8mV/us
+ * 11: 4mV/us
+ */
+static int mpq7920_set_ramp_delay(struct regulator_dev *rdev, int ramp_delay)
+{
+	unsigned int ramp_val;
+
+	if (ramp_delay > 8000 || ramp_delay < 0)
+		return -EINVAL;
+
+	if (ramp_delay <= 4000)
+		ramp_val = 3;
+	else
+		ramp_val = 2;
+
+	return regmap_update_bits(rdev->regmap, MPQ7920_REG_CTL0,
+				  MPQ7920_MASK_DVS_SLEWRATE, ramp_val << 6);
+}
+
+static void mpq7920_parse_dt(struct device *dev,
+			 struct mpq7920_regulator_info *info)
+{
+	int ret, i;
+	struct device_node *np = dev->of_node;
+	uint8_t freq;
+	uint8_t time_slot;
+	uint8_t val[MPQ7920_BUCK4 + 1];
+	uint8_t var_time[MPQ7920_LDO5];
+	bool is_fixed_on_time = 0;
+	bool is_fixed_off_time = 0;
+
+	is_fixed_on_time = of_property_read_bool(np, "mps,fixed-on-time");
+	is_fixed_off_time = of_property_read_bool(np, "mps,fixed-off-time");
+	if (is_fixed_on_time || is_fixed_off_time) {
+		regmap_update_bits(info->regmap, MPQ7920_REG_CTL2,
+				MPQ7920_MASK_FIXED_TIME_SLOT,
+				~(is_fixed_on_time << 1 | is_fixed_off_time));
+	}
+
+	ret = of_property_read_u8(np, "mps,time-slot", &time_slot);
+	if (!ret) {
+		regmap_update_bits(info->regmap, MPQ7920_REG_CTL2,
+					MPQ7920_MASK_TIME_SLOT,
+					(time_slot & 3) << 2);
+	}
+
+	if (!is_fixed_on_time &&
+	    !of_property_read_u8_array(np, "mps,inc-on-time", var_time,
+					ARRAY_SIZE(var_time))) {
+
+		for (i = 0; i < MPQ7920_LDO5; i++) {
+			if (i <= MPQ7920_BUCK4) {
+				regmap_update_bits(info->regmap,
+					MPQ7920_BUCK1_REG_D + (i * 4),
+					MPQ7920_MASK_ON_TIME_SLOT,
+					var_time[i] & 0xF);
+			} else {
+				regmap_update_bits(info->regmap,
+					(MPQ7920_LDO2_REG_C +
+						((i - MPQ7920_LDO1) * 3)),
+					MPQ7920_MASK_ON_TIME_SLOT,
+					var_time[i] & 0xF);
+			}
+		}
+	}
+
+	if (!is_fixed_off_time &&
+	    !of_property_read_u8_array(np, "mps,inc-off-time", var_time,
+					ARRAY_SIZE(var_time))) {
+
+		for (i = 0; i < MPQ7920_LDO5; i++) {
+			if (i <= MPQ7920_BUCK4) {
+				regmap_update_bits(info->regmap,
+					MPQ7920_BUCK1_REG_D + (i * 4),
+					MPQ7920_MASK_OFF_TIME_SLOT,
+					(var_time[i] & 0xF) << 4);
+			} else {
+				regmap_update_bits(info->regmap,
+					(MPQ7920_LDO2_REG_C +
+						((i - MPQ7920_LDO1) * 3)),
+					MPQ7920_MASK_OFF_TIME_SLOT,
+					(var_time[i] & 0xF) << 4);
+			}
+		}
+	}
+
+	ret = of_property_read_u8_array(np, "mps,buck-softstart", val,
+					ARRAY_SIZE(val));
+	if (!ret) {
+		for (i = 0; i < ARRAY_SIZE(val); i++)
+			info->rdesc[i].soft_start_val_on = (val[i] & 3) << 2;
+	}
+
+	ret = of_property_read_u8_array(np, "mps,buck-ovp", val,
+					ARRAY_SIZE(val));
+	if (!ret) {
+		for (i = 0; i <= MPQ7920_BUCK4; i++) {
+			regmap_update_bits(info->regmap,
+					MPQ7920_BUCK1_REG_B + (i * 4),
+					BIT(6), val[i] << 6);
+		}
+	}
+
+	ret = of_property_read_u8_array(np, "mps,buck-phase-delay", val,
+					ARRAY_SIZE(val));
+	if (!ret) {
+		for (i = 0; i <= MPQ7920_BUCK4; i++) {
+			regmap_update_bits(info->regmap,
+					MPQ7920_BUCK1_REG_C + (i * 4),
+					MPQ7920_MASK_BUCK_PHASE_DEALY,
+					(val[i] & 3) << 4);
+		}
+	}
+
+	ret = of_property_read_u8(np, "mps,switch-freq", &freq);
+	if (!ret) {
+		regmap_update_bits(info->regmap, MPQ7920_REG_CTL0,
+					MPQ7920_MASK_SWITCH_FREQ,
+					(freq & 3) << 4);
+	}
+}
+
+static inline int mpq7920_regulator_register(
+				struct mpq7920_regulator_info *info,
+				struct regulator_config *config)
+{
+	int i;
+	struct regulator_desc *rdesc;
+
+	for (i = 0; i < MPQ7920_MAX_REGULATORS; i++) {
+		rdesc = &info->rdesc[i];
+
+		info->rdev[i] = devm_regulator_register(info->dev, rdesc,
+					 config);
+		if (IS_ERR(info->rdev))
+			return PTR_ERR(info->rdev);
+	}
+
+	return 0;
+}
+
+static int mpq7920_i2c_probe(struct i2c_client *client,
+				    const struct i2c_device_id *id)
+{
+	struct device *dev = &client->dev;
+	struct mpq7920_regulator_info *info;
+	struct regulator_config config = { NULL, };
+	struct regmap *regmap;
+	int ret;
+
+	info = devm_kzalloc(dev, sizeof(struct mpq7920_regulator_info),
+				GFP_KERNEL);
+	if (!info)
+		return -ENOMEM;
+
+	info->dev = dev;
+	info->rdesc = mpq7920_regulators_desc;
+	regmap = devm_regmap_init_i2c(client, &mpq7920_regmap_config);
+	if (IS_ERR(regmap)) {
+		dev_err(dev, "Failed to allocate regmap!\n");
+		return PTR_ERR(regmap);
+	}
+
+	i2c_set_clientdata(client, info);
+	info->regmap = regmap;
+	if (client->dev.of_node)
+		mpq7920_parse_dt(&client->dev, info);
+
+	config.dev = info->dev;
+	config.regmap = regmap;
+	config.driver_data = info;
+
+	ret = mpq7920_regulator_register(info, &config);
+	if (ret < 0)
+		dev_err(dev, "Failed to register regulator!\n");
+
+	return ret;
+}
+
+static const struct of_device_id mpq7920_of_match[] = {
+	{ .compatible = "mps,mpq7920"},
+	{},
+};
+MODULE_DEVICE_TABLE(of, mpq7920_of_match);
+
+static const struct i2c_device_id mpq7920_id[] = {
+	{ "mpq7920", },
+	{ },
+};
+MODULE_DEVICE_TABLE(i2c, mpq7920_id);
+
+static struct i2c_driver mpq7920_regulator_driver = {
+	.driver = {
+		.name = "mpq7920",
+		.of_match_table = of_match_ptr(mpq7920_of_match),
+	},
+	.probe = mpq7920_i2c_probe,
+	.id_table = mpq7920_id,
+};
+module_i2c_driver(mpq7920_regulator_driver);
+
+MODULE_AUTHOR("Saravanan Sekar <sravanhome@gmail.com>");
+MODULE_DESCRIPTION("MPQ7920 PMIC regulator driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/regulator/mpq7920.h b/drivers/regulator/mpq7920.h
new file mode 100644
index 000000000000..58c64e708f2e
--- /dev/null
+++ b/drivers/regulator/mpq7920.h
@@ -0,0 +1,72 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * mpq7920.h  -  Regulator definitions for mpq7920
+ *
+ * Copyright 2019 Monolithic Power Systems, Inc
+ *
+ */
+
+#ifndef __MPQ7920_H__
+#define __MPQ7920_H__
+
+#define MPQ7920_REG_CTL0		0x00
+#define MPQ7920_REG_CTL1		0x01
+#define MPQ7920_REG_CTL2		0x02
+#define MPQ7920_BUCK1_REG_A		0x03
+#define MPQ7920_BUCK1_REG_B		0x04
+#define MPQ7920_BUCK1_REG_C		0x05
+#define MPQ7920_BUCK1_REG_D		0x06
+#define MPQ7920_BUCK2_REG_A		0x07
+#define MPQ7920_BUCK2_REG_B		0x08
+#define MPQ7920_BUCK2_REG_C		0x09
+#define MPQ7920_BUCK2_REG_D		0x0a
+#define MPQ7920_BUCK3_REG_A		0x0b
+#define MPQ7920_BUCK3_REG_B		0x0c
+#define MPQ7920_BUCK3_REG_C		0x0d
+#define MPQ7920_BUCK3_REG_D		0x0e
+#define MPQ7920_BUCK4_REG_A		0x0f
+#define MPQ7920_BUCK4_REG_B		0x10
+#define MPQ7920_BUCK4_REG_C		0x11
+#define MPQ7920_BUCK4_REG_D		0x12
+#define MPQ7920_LDO1_REG_A		0x13
+#define MPQ7920_LDO1_REG_B		0x0
+#define MPQ7920_LDO2_REG_A		0x14
+#define MPQ7920_LDO2_REG_B		0x15
+#define MPQ7920_LDO2_REG_C		0x16
+#define MPQ7920_LDO3_REG_A		0x17
+#define MPQ7920_LDO3_REG_B		0x18
+#define MPQ7920_LDO3_REG_C		0x19
+#define MPQ7920_LDO4_REG_A		0x1a
+#define MPQ7920_LDO4_REG_B		0x1b
+#define MPQ7920_LDO4_REG_C		0x1c
+#define MPQ7920_LDO5_REG_A		0x1d
+#define MPQ7920_LDO5_REG_B		0x1e
+#define MPQ7920_LDO5_REG_C		0x1f
+#define MPQ7920_REG_MODE		0x20
+#define MPQ7920_REG_REGULATOR_EN1	0x22
+#define MPQ7920_REG_REGULATOR_EN	0x22
+
+#define MPQ7920_MASK_VREF		0x7f
+#define MPQ7920_MASK_BUCK_ILIM		0xd0
+#define MPQ7920_MASK_LDO_ILIM		BIT(6)
+#define MPQ7920_MASK_DISCHARGE		BIT(5)
+#define MPQ7920_MASK_MODE		0xc0
+#define MPQ7920_MASK_SOFTSTART		0x0c
+#define MPQ7920_MASK_SWITCH_FREQ	0x30
+#define MPQ7920_MASK_BUCK_PHASE_DEALY	0x30
+#define MPQ7920_MASK_DVS_SLEWRATE	0xc0
+#define MPQ7920_MASK_TIME_SLOT		0x06
+#define MPQ7920_MASK_FIXED_TIME_SLOT	0x03
+#define MPQ7920_MASK_ON_TIME_SLOT	0x0F
+#define MPQ7920_MASK_OFF_TIME_SLOT	0xF0
+#define MPQ7920_DISCHARGE_ON		0x1
+
+#define MPQ7920_REGULATOR_EN_OFFSET	7
+
+/* values in mV */
+#define MPQ7920_BUCK_VOLT_MIN		400000
+#define MPQ7920_LDO_VOLT_MIN		650000
+#define MPQ7920_VOLT_MAX		3587500
+#define MPQ7920_VOLT_STEP		12500
+
+#endif /* __MPQ7920_H__ */
-- 
2.17.1

[PATCH v4 4/4] MAINTAINERS: Add entry for mpq7920 PMIC driver

[Saravanan Sekar]

Add MAINTAINERS entry for Monolithic Power Systems mpq7920 PMIC driver.

Signed-off-by: Saravanan Sekar <sravanhome@gmail.com>
---
 MAINTAINERS | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index 0fd82e674cf4..8a31285b59c6 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11128,6 +11128,13 @@ S:	Maintained
 F:	Documentation/driver-api/serial/moxa-smartio.rst
 F:	drivers/tty/mxser.*
 
+MONOLITHIC POWER SYSTEM PMIC DRIVER
+M:	Saravanan Sekar <sravanhome@gmail.com>
+S:	Maintained
+F:	Documentation/devicetree/bindings/regulator/mpq7920.yaml
+F:	drivers/regulator/mpq7920.c
+F:	drivers/regulator/mpq7920.h
+
 MR800 AVERMEDIA USB FM RADIO DRIVER
 M:	Alexey Klimov <klimov.linux@gmail.com>
 L:	linux-media@vger.kernel.org
-- 
2.17.1

Re: [PATCH v4 1/4] dt-bindings: Add an entry for Monolithic Power System, MPS

[Rob Herring]

On Thu, 26 Dec 2019 23:29:27 +0100, Saravanan Sekar wrote:
> Add an entry for Monolithic Power System, MPS
> 
> Signed-off-by: Saravanan Sekar <sravanhome@gmail.com>
> ---
>  Documentation/devicetree/bindings/vendor-prefixes.yaml | 2 ++
>  1 file changed, 2 insertions(+)
> 

Acked-by: Rob Herring <robh@kernel.org>

Re: [PATCH v4 2/4] dt-bindings: regulator: add document bindings for mpq7920

[Rob Herring]

On Thu, Dec 26, 2019 at 11:29:28PM +0100, Saravanan Sekar wrote:
> Add device tree binding information for mpq7920 regulator driver.
> Example bindings for mpq7920 are added.
> 
> Signed-off-by: Saravanan Sekar <sravanhome@gmail.com>
> ---
>  .../bindings/regulator/mpq7920.yaml           | 143 ++++++++++++++++++

Convention is use the compatible string: mps,mpq7920.yaml

>  1 file changed, 143 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/regulator/mpq7920.yaml
> 
> diff --git a/Documentation/devicetree/bindings/regulator/mpq7920.yaml b/Documentation/devicetree/bindings/regulator/mpq7920.yaml
> new file mode 100644
> index 000000000000..54e9177dfd1b
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/regulator/mpq7920.yaml
> @@ -0,0 +1,143 @@
> +# SPDX-License-Identifier: GPL-2.0

Dual license new bindings:

(GPL-2.0-only OR BSD-2-Clause)

> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/regulator/mpq7920.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Monolithic Power System MPQ7920 PMIC
> +
> +maintainers:
> +  - Saravanan Sekar <sravanhome@gmail.com>
> +
> +properties:
> +  $nodename:
> +    pattern: "pmic@[0-9a-f]{1,2}"
> +  compatible:
> +    enum:
> +      - mps,mpq7920
> +
> +  reg:
> +    maxItems: 1
> +
> +  mps,time-slot:
> +    description:
> +      each regulator output shall be delayed during power on/off sequence which
> +      based on configurable time slot value, must be one of following corresponding
> +      value 0.5ms, 2ms, 8ms, 16ms

These values map to 0-3?

This value is how long each time slot is?

> +    allOf:
> +      - $ref: "/schemas/types.yaml#/definitions/uint8"
> +      - enum: [ 0, 1, 2, 3 ]
> +      - default: 0

Only $ref needs to be under the allOf, so move enum and default to same 
level as allOf.

> +
> +  mps,fixed-on-time:
> +     description:
> +       select power on sequence with fixed time output delay mentioned in
> +       time-slot reg for all the regulators.
> +     type: boolean
> +
> +  mps,fixed-off-time:
> +     description:
> +        select power off sequence with fixed time output delay mentioned in
> +        time-slot reg for all the regulators.
> +     type: boolean
> +
> +  mps,inc-off-time:
> +     description: |
> +        mutually exclusive to mps,fixed-off-time an array of 8, linearly increase
> +        output delay during power off sequence based on factor of time slot/interval
> +        for each regulator.
> +     allOf:
> +       - $ref: "/schemas/types.yaml#/definitions/uint8-array"
> +       - minimum: 0
> +       - maximum: 15
> +       - default: [ 0, 6, 0, 6, 7, 7, 7, 9 ]

Each value corresponds to a regulator? Why not a per regulator property?

> +
> +  mps,inc-on-time:
> +     description: |
> +        mutually exclusive to mps,fixed-on-time an array of 8, linearly increase
> +        output delay during power on sequence based on factor of time slot/interval
> +        for each regulator.
> +     allOf:
> +       - $ref: "/schemas/types.yaml#/definitions/uint8-array"
> +       - minimum: 0
> +       - maximum: 15
> +       - default: [ 0, 6, 0, 6, 7, 7, 7, 9 ]
> +
> +  mps,switch-freq:
> +     description: |
> +        switching frequency must be one of following corresponding value
> +        1.1MHz, 1.65MHz, 2.2MHz, 2.75MHz

Seems like this should be a common property.

> +     allOf:
> +       - $ref: "/schemas/types.yaml#/definitions/uint8"
> +       - enum: [ 0, 1, 2, 3 ]
> +       - default: 2
> +
> +  mps,buck-softstart:
> +     description: |
> +        An array of 4 contains soft start time of each buck, must be one of
> +        following corresponding values 150us, 300us, 610us, 920us
> +     allOf:
> +       - $ref: "/schemas/types.yaml#/definitions/uint8-array"
> +       - enum: [ 0, 1, 2, 3 ]

As this is an array, should be:

items:
  enum: ...

Constraints on the size of the array?

Though again, why not a per regulator property? Also, a fairly common 
thing for buck regulators?

> +       - default: [ 1, 1, 1, 1 ]
> +
> +  mps,buck-ovp:
> +     description: |
> +        An array of 4 contains over voltage protection of each buck, must be
> +        one of above values
> +     allOf:
> +       - $ref: "/schemas/types.yaml#/definitions/uint8-array"
> +       - enum: [ 0, 1 ]
> +       - default: [ 1, 1, 1, 1 ]
> +
> +  mps,buck-phase-delay:
> +     description: |
> +        An array of 4 contains phase delay of each buck must be one of above values
> +        corresponding to 0deg, 90deg, 180deg, 270deg
> +     allOf:
> +       - $ref: "/schemas/types.yaml#/definitions/uint8-array"
> +       - enum: [ 0, 1, 2, 3 ]
> +       - default: [ 0, 0, 1, 1 ]
> +
> +  regulators:
> +    type: object
> +    description:
> +      list of regulators provided by this controller, must be named
> +      after their hardware counterparts BUCK[1-4], one LDORTC, and LDO[2-5]
> +      The valid names for regulators are
> +      buck1, buck2, buck3, buck4, ldortc, ldo2, ldo3, ldo4, ldo5

You need buck[1-4] and ldo(rtc|[2-5]) child nodes defined here which 
reference regulators.yaml.

> +
> +
> +examples:
> +  - |
> +    i2c {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        pmic@69 {
> +          compatible = "mps,mpq7920";
> +          reg = <0x69>;
> +
> +          mps,switch-freq = <1>;
> +          mps,buck-softstart = /bits/ 8 <1 2 1 3>;
> +          mps,buck-ovp = /bits/ 8 <1 0 1 1>;
> +
> +          regulators {
> +            buck1 {
> +             regulator-name = "buck1";
> +             regulator-min-microvolt = <400000>;
> +             regulator-max-microvolt = <3587500>;
> +             regulator-min-microamp  = <460000>;
> +             regulator-max-microamp  = <7600000>;
> +             regulator-boot-on;
> +            };
> +
> +            ldo2 {
> +             regulator-name = "ldo2";
> +             regulator-min-microvolt = <650000>;
> +             regulator-max-microvolt = <3587500>;
> +            };
> +         };
> +       };
> +     };
> +...
> -- 
> 2.17.1
>