Merge series "Support ROHM BD9576MUF and BD9573MUF PMICs" from Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>:

Initial support for ROHM BD9576MUF and BD9573MUF PMICs.

These PMICs are primarily intended to be used to power the R-Car family
processors. BD9576MUF includes some additional safety features the
BD9573MUF does not have. This initial version of drivers does not
utilize these features and for now the SW behaviour is identical.

Please note that this version of drivers is only tested on BD9576MUF
but according to the data-sheets the relevant parts of registers should
be same so drivers should also work on BD9573MUF.

This patch series includes MFD, watchdog and regulator drivers with
basic functionality such as:

- Enabling and pinging the watchdog
- configuring watchog timeout / window from device-tree
- reading regulator states/voltages
- enabling/disabling VOUT1 (VD50) when control mode B is used.

This patch series does not bring interrupt support. BD9576MUF and BD9573MUF
are designed to keep the IRQ line low for whole duration of error
condition. IRQ can't be 'acked'. So proper IRQ support would require
some IRQ limiter implementation (delayed unmask?) in order to not hog
the CPU.

---

Matti Vaittinen (6):
  dt_bindings: mfd: Add ROHM BD9576MUF and BD9573MUF PMICs
  dt_bindings: regulator: Add ROHM BD9576MUF and BD9573MUF PMICs
  mfd: Support ROHM BD9576MUF and BD9573MUF
  wdt: Support wdt on ROHM BD9576MUF and BD9573MUF
  regulator: Support ROHM BD9576MUF and BD9573MUF
  MAINTAINERS: Add ROHM BD9576MUF and BD9573MUF drivers

 .../bindings/mfd/rohm,bd9576-pmic.yaml        | 129 +++++++
 .../regulator/rohm,bd9576-regulator.yaml      |  33 ++
 MAINTAINERS                                   |   4 +
 drivers/mfd/Kconfig                           |  11 +
 drivers/mfd/Makefile                          |   1 +
 drivers/mfd/rohm-bd9576.c                     | 130 +++++++
 drivers/regulator/Kconfig                     |  10 +
 drivers/regulator/Makefile                    |   1 +
 drivers/regulator/bd9576-regulator.c          | 337 ++++++++++++++++++
 drivers/watchdog/Kconfig                      |  13 +
 drivers/watchdog/Makefile                     |   1 +
 drivers/watchdog/bd9576_wdt.c                 | 295 +++++++++++++++
 include/linux/mfd/rohm-bd957x.h               |  61 ++++
 include/linux/mfd/rohm-generic.h              |   2 +
 14 files changed, 1028 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mfd/rohm,bd9576-pmic.yaml
 create mode 100644 Documentation/devicetree/bindings/regulator/rohm,bd9576-regulator.yaml
 create mode 100644 drivers/mfd/rohm-bd9576.c
 create mode 100644 drivers/regulator/bd9576-regulator.c
 create mode 100644 drivers/watchdog/bd9576_wdt.c
 create mode 100644 include/linux/mfd/rohm-bd957x.h

base-commit: f4d51dffc6c01a9e94650d95ce0104964f8ae822
--
2.21.0

--
Matti Vaittinen, Linux device drivers
ROHM Semiconductors, Finland SWDC
Kiviharjunlenkki 1E
90220 OULU
FINLAND

~~~ "I don't think so," said Rene Descartes. Just then he vanished ~~~
Simon says - in Latin please.
~~~ "non cogito me" dixit Rene Descarte, deinde evanescavit ~~~
Thanks to Simon Glass for the translation =]

7 files changed, 355 insertions, 7 deletions

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 0c0b4f3652fb..4efa27b0f9f5 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -231,6 +231,16 @@ config REGULATOR_BD9571MWV
 	  This driver can also be built as a module. If so, the module
 	  will be called bd9571mwv-regulator.
 
+config REGULATOR_BD957XMUF
+	tristate "ROHM BD9576MUF and BD9573MUF Regulators"
+	depends on MFD_ROHM_BD957XMUF
+	help
+	  This driver supports voltage regulators on ROHM BD9576MUF and
+	  BD9573MUF PMICs.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called bd9576-regulator.
+
 config REGULATOR_CPCAP
 	tristate "Motorola CPCAP regulator"
 	depends on MFD_CPCAP
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index d958cc8c5360..cf908f67b486 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -32,6 +32,7 @@ obj-$(CONFIG_REGULATOR_BD70528) += bd70528-regulator.o
 obj-$(CONFIG_REGULATOR_BD71828) += bd71828-regulator.o
 obj-$(CONFIG_REGULATOR_BD718XX) += bd718x7-regulator.o
 obj-$(CONFIG_REGULATOR_BD9571MWV) += bd9571mwv-regulator.o
+obj-$(CONFIG_REGULATOR_BD957XMUF) += bd9576-regulator.o
 obj-$(CONFIG_REGULATOR_DA903X)	+= da903x-regulator.o
 obj-$(CONFIG_REGULATOR_DA9052)	+= da9052-regulator.o
 obj-$(CONFIG_REGULATOR_DA9055)	+= da9055-regulator.o
diff --git a/drivers/regulator/axp20x-regulator.c b/drivers/regulator/axp20x-regulator.c
index fbc95cadaf53..1bacb37e8a99 100644
--- a/drivers/regulator/axp20x-regulator.c
+++ b/drivers/regulator/axp20x-regulator.c
@@ -399,7 +399,7 @@ static int axp20x_set_ramp_delay(struct regulator_dev *rdev, int ramp)
 		if (rate_count > 0)
 			break;
 
-		/* fall through */
+		fallthrough;
 	default:
 		/* Not supported for this regulator */
 		return -ENOTSUPP;
@@ -1022,7 +1022,7 @@ static int axp20x_set_dcdc_freq(struct platform_device *pdev, u32 dcdcfreq)
 		 * (See include/linux/mfd/axp20x.h)
 		 */
 		reg = AXP803_DCDC_FREQ_CTRL;
-		/* Fall through - to the check below.*/
+		fallthrough;	/* to the check below */
 	case AXP806_ID:
 		/*
 		 * AXP806 also have DCDC work frequency setting register at a
@@ -1030,7 +1030,7 @@ static int axp20x_set_dcdc_freq(struct platform_device *pdev, u32 dcdcfreq)
 		 */
 		if (axp20x->variant == AXP806_ID)
 			reg = AXP806_DCDC_FREQ_CTRL;
-		/* Fall through */
+		fallthrough;
 	case AXP221_ID:
 	case AXP223_ID:
 	case AXP809_ID:
@@ -1118,7 +1118,7 @@ static int axp20x_set_dcdc_workmode(struct regulator_dev *rdev, int id, u32 work
 		 * (See include/linux/mfd/axp20x.h)
 		 */
 		reg = AXP806_DCDC_MODE_CTRL2;
-		 /* Fall through - to the check below. */
+		fallthrough;	/* to the check below */
 	case AXP221_ID:
 	case AXP223_ID:
 	case AXP809_ID:
diff --git a/drivers/regulator/bd9576-regulator.c b/drivers/regulator/bd9576-regulator.c
new file mode 100644
index 000000000000..4137fa9a73bb
--- /dev/null
+++ b/drivers/regulator/bd9576-regulator.c
@@ -0,0 +1,337 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2020 ROHM Semiconductors
+// ROHM BD9576MUF/BD9573MUF regulator driver
+
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/gpio/consumer.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/mfd/rohm-bd957x.h>
+#include <linux/mfd/rohm-generic.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/regulator/of_regulator.h>
+#include <linux/slab.h>
+
+#define BD957X_VOUTS1_VOLT	3300000
+#define BD957X_VOUTS4_BASE_VOLT	1030000
+#define BD957X_VOUTS34_NUM_VOLT	32
+
+static int vout1_volt_table[] = {5000000, 4900000, 4800000, 4700000, 4600000,
+				 4500000, 4500000, 4500000, 5000000, 5100000,
+				 5200000, 5300000, 5400000, 5500000, 5500000,
+				 5500000};
+
+static int vout2_volt_table[] = {1800000, 1780000, 1760000, 1740000, 1720000,
+				 1700000, 1680000, 1660000, 1800000, 1820000,
+				 1840000, 1860000, 1880000, 1900000, 1920000,
+				 1940000};
+
+static int voutl1_volt_table[] = {2500000, 2540000, 2580000, 2620000, 2660000,
+				  2700000, 2740000, 2780000, 2500000, 2460000,
+				  2420000, 2380000, 2340000, 2300000, 2260000,
+				  2220000};
+
+struct bd957x_regulator_data {
+	struct regulator_desc desc;
+	int base_voltage;
+};
+
+static int bd957x_vout34_list_voltage(struct regulator_dev *rdev,
+				      unsigned int selector)
+{
+	const struct regulator_desc *desc = rdev->desc;
+	int multiplier = selector & desc->vsel_mask & 0x7f;
+	int tune;
+
+	/* VOUT3 and 4 has 10mV step */
+	tune = multiplier * 10000;
+
+	if (!(selector & 0x80))
+		return desc->fixed_uV - tune;
+
+	return desc->fixed_uV + tune;
+}
+
+static int bd957x_list_voltage(struct regulator_dev *rdev,
+			       unsigned int selector)
+{
+	const struct regulator_desc *desc = rdev->desc;
+	int index = selector & desc->vsel_mask & 0x7f;
+
+	if (!(selector & 0x80))
+		index += desc->n_voltages/2;
+
+	if (index >= desc->n_voltages)
+		return -EINVAL;
+
+	return desc->volt_table[index];
+}
+
+static const struct regulator_ops bd957x_vout34_ops = {
+	.is_enabled = regulator_is_enabled_regmap,
+	.list_voltage = bd957x_vout34_list_voltage,
+	.get_voltage_sel = regulator_get_voltage_sel_regmap,
+};
+
+static const struct regulator_ops bd957X_vouts1_regulator_ops = {
+	.is_enabled = regulator_is_enabled_regmap,
+};
+
+static const struct regulator_ops bd957x_ops = {
+	.is_enabled = regulator_is_enabled_regmap,
+	.list_voltage = bd957x_list_voltage,
+	.get_voltage_sel = regulator_get_voltage_sel_regmap,
+};
+
+static struct bd957x_regulator_data bd9576_regulators[] = {
+	{
+		.desc = {
+			.name = "VD50",
+			.of_match = of_match_ptr("regulator-vd50"),
+			.regulators_node = of_match_ptr("regulators"),
+			.id = BD957X_VD50,
+			.type = REGULATOR_VOLTAGE,
+			.ops = &bd957x_ops,
+			.volt_table = &vout1_volt_table[0],
+			.n_voltages = ARRAY_SIZE(vout1_volt_table),
+			.vsel_reg = BD957X_REG_VOUT1_TUNE,
+			.vsel_mask = BD957X_MASK_VOUT1_TUNE,
+			.enable_reg = BD957X_REG_POW_TRIGGER1,
+			.enable_mask = BD957X_REGULATOR_EN_MASK,
+			.enable_val = BD957X_REGULATOR_DIS_VAL,
+			.enable_is_inverted = true,
+			.owner = THIS_MODULE,
+		},
+	},
+	{
+		.desc = {
+			.name = "VD18",
+			.of_match = of_match_ptr("regulator-vd18"),
+			.regulators_node = of_match_ptr("regulators"),
+			.id = BD957X_VD18,
+			.type = REGULATOR_VOLTAGE,
+			.ops = &bd957x_ops,
+			.volt_table = &vout2_volt_table[0],
+			.n_voltages = ARRAY_SIZE(vout2_volt_table),
+			.vsel_reg = BD957X_REG_VOUT2_TUNE,
+			.vsel_mask = BD957X_MASK_VOUT2_TUNE,
+			.enable_reg = BD957X_REG_POW_TRIGGER2,
+			.enable_mask = BD957X_REGULATOR_EN_MASK,
+			.enable_val = BD957X_REGULATOR_DIS_VAL,
+			.enable_is_inverted = true,
+			.owner = THIS_MODULE,
+		},
+	},
+	{
+		.desc = {
+			.name = "VDDDR",
+			.of_match = of_match_ptr("regulator-vdddr"),
+			.regulators_node = of_match_ptr("regulators"),
+			.id = BD957X_VDDDR,
+			.ops = &bd957x_vout34_ops,
+			.type = REGULATOR_VOLTAGE,
+			.n_voltages = BD957X_VOUTS34_NUM_VOLT,
+			.vsel_reg = BD957X_REG_VOUT3_TUNE,
+			.vsel_mask = BD957X_MASK_VOUT3_TUNE,
+			.enable_reg = BD957X_REG_POW_TRIGGER3,
+			.enable_mask = BD957X_REGULATOR_EN_MASK,
+			.enable_val = BD957X_REGULATOR_DIS_VAL,
+			.enable_is_inverted = true,
+			.owner = THIS_MODULE,
+		},
+	},
+	{
+		.desc = {
+			.name = "VD10",
+			.of_match = of_match_ptr("regulator-vd10"),
+			.regulators_node = of_match_ptr("regulators"),
+			.id = BD957X_VD10,
+			.ops = &bd957x_vout34_ops,
+			.type = REGULATOR_VOLTAGE,
+			.fixed_uV = BD957X_VOUTS4_BASE_VOLT,
+			.n_voltages = BD957X_VOUTS34_NUM_VOLT,
+			.vsel_reg = BD957X_REG_VOUT4_TUNE,
+			.vsel_mask = BD957X_MASK_VOUT4_TUNE,
+			.enable_reg = BD957X_REG_POW_TRIGGER4,
+			.enable_mask = BD957X_REGULATOR_EN_MASK,
+			.enable_val = BD957X_REGULATOR_DIS_VAL,
+			.enable_is_inverted = true,
+			.owner = THIS_MODULE,
+		},
+	},
+	{
+		.desc = {
+			.name = "VOUTL1",
+			.of_match = of_match_ptr("regulator-voutl1"),
+			.regulators_node = of_match_ptr("regulators"),
+			.id = BD957X_VOUTL1,
+			.ops = &bd957x_ops,
+			.type = REGULATOR_VOLTAGE,
+			.volt_table = &voutl1_volt_table[0],
+			.n_voltages = ARRAY_SIZE(voutl1_volt_table),
+			.vsel_reg = BD957X_REG_VOUTL1_TUNE,
+			.vsel_mask = BD957X_MASK_VOUTL1_TUNE,
+			.enable_reg = BD957X_REG_POW_TRIGGERL1,
+			.enable_mask = BD957X_REGULATOR_EN_MASK,
+			.enable_val = BD957X_REGULATOR_DIS_VAL,
+			.enable_is_inverted = true,
+			.owner = THIS_MODULE,
+		},
+	},
+	{
+		.desc = {
+			.name = "VOUTS1",
+			.of_match = of_match_ptr("regulator-vouts1"),
+			.regulators_node = of_match_ptr("regulators"),
+			.id = BD957X_VOUTS1,
+			.ops = &bd957X_vouts1_regulator_ops,
+			.type = REGULATOR_VOLTAGE,
+			.n_voltages = 1,
+			.fixed_uV = BD957X_VOUTS1_VOLT,
+			.enable_reg = BD957X_REG_POW_TRIGGERS1,
+			.enable_mask = BD957X_REGULATOR_EN_MASK,
+			.enable_val = BD957X_REGULATOR_DIS_VAL,
+			.enable_is_inverted = true,
+			.owner = THIS_MODULE,
+		},
+	},
+};
+
+static int bd957x_probe(struct platform_device *pdev)
+{
+	struct regmap *regmap;
+	struct regulator_config config = { 0 };
+	int i, err;
+	bool vout_mode, ddr_sel;
+	const struct bd957x_regulator_data *reg_data = &bd9576_regulators[0];
+	unsigned int num_reg_data = ARRAY_SIZE(bd9576_regulators);
+	enum rohm_chip_type chip = platform_get_device_id(pdev)->driver_data;
+
+	regmap = dev_get_regmap(pdev->dev.parent, NULL);
+	if (!regmap) {
+		dev_err(&pdev->dev, "No regmap\n");
+		return -EINVAL;
+	}
+	vout_mode = of_property_read_bool(pdev->dev.parent->of_node,
+					 "rohm,vout1-en-low");
+	if (vout_mode) {
+		struct gpio_desc *en;
+
+		dev_dbg(&pdev->dev, "GPIO controlled mode\n");
+
+		/* VOUT1 enable state judged by VOUT1_EN pin */
+		/* See if we have GPIO defined */
+		en = devm_gpiod_get_from_of_node(&pdev->dev,
+						 pdev->dev.parent->of_node,
+						 "rohm,vout1-en-gpios", 0,
+						 GPIOD_OUT_LOW, "vout1-en");
+		if (!IS_ERR(en)) {
+			/* VOUT1_OPS gpio ctrl */
+			/*
+			 * Regulator core prioritizes the ena_gpio over
+			 * enable/disable/is_enabled callbacks so no need to
+			 * clear them. We can still use same ops
+			 */
+			config.ena_gpiod = en;
+		} else {
+			/*
+			 * In theory it is possible someone wants to set
+			 * vout1-en LOW during OTP loading and set VOUT1 to be
+			 * controlled by GPIO - but control the GPIO from some
+			 * where else than this driver. For that to work we
+			 * should unset the is_enabled callback here.
+			 *
+			 * I believe such case where rohm,vout1-en-low is set
+			 * and vout1-en-gpios is not is likely to be a
+			 * misconfiguration. So let's just err out for now.
+			 */
+			dev_err(&pdev->dev,
+				"Failed to get VOUT1 control GPIO\n");
+			return PTR_ERR(en);
+		}
+	}
+
+	/*
+	 * If more than one PMIC needs to be controlled by same processor then
+	 * allocate the regulator data array here and use bd9576_regulators as
+	 * template. At the moment I see no such use-case so I spare some
+	 * bytes and use bd9576_regulators directly for non-constant configs
+	 * like DDR voltage selection.
+	 */
+	ddr_sel =  of_property_read_bool(pdev->dev.parent->of_node,
+					 "rohm,ddr-sel-low");
+	if (ddr_sel)
+		bd9576_regulators[2].desc.fixed_uV = 1350000;
+	else
+		bd9576_regulators[2].desc.fixed_uV = 1500000;
+
+	switch (chip) {
+	case ROHM_CHIP_TYPE_BD9576:
+		dev_dbg(&pdev->dev, "Found BD9576MUF\n");
+		break;
+	case ROHM_CHIP_TYPE_BD9573:
+		pr_info(&pdev->dev, "Found BD9573MUF\n");
+		break;
+	default:
+		dev_err(&pdev->dev, "Unsupported chip type\n");
+		err = -EINVAL;
+		goto err;
+	}
+
+	config.dev = pdev->dev.parent;
+	config.regmap = regmap;
+
+	for (i = 0; i < num_reg_data; i++) {
+
+		const struct regulator_desc *desc;
+		struct regulator_dev *rdev;
+		const struct bd957x_regulator_data *r;
+
+		r = &reg_data[i];
+		desc = &r->desc;
+
+		rdev = devm_regulator_register(&pdev->dev, desc, &config);
+		if (IS_ERR(rdev)) {
+			dev_err(&pdev->dev,
+				"failed to register %s regulator\n",
+				desc->name);
+			err = PTR_ERR(rdev);
+			goto err;
+		}
+		/*
+		 * Clear the VOUT1 GPIO setting - rest of the regulators do not
+		 * support GPIO control
+		 */
+		config.ena_gpiod = NULL;
+	}
+
+err:
+	return err;
+}
+
+static const struct platform_device_id bd957x_pmic_id[] = {
+	{ "bd9573-pmic", ROHM_CHIP_TYPE_BD9573 },
+	{ "bd9576-pmic", ROHM_CHIP_TYPE_BD9576 },
+	{ },
+};
+MODULE_DEVICE_TABLE(platform, bd957x_pmic_id);
+
+static struct platform_driver bd957x_regulator = {
+	.driver = {
+		.name = "bd957x-pmic",
+	},
+	.probe = bd957x_probe,
+	.id_table = bd957x_pmic_id,
+};
+
+module_platform_driver(bd957x_regulator);
+
+MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>");
+MODULE_DESCRIPTION("ROHM BD9576/BD9573 voltage regulator driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:bd957x-pmic");
diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 2ed035114ee8..a9c97c88f50e 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -1926,7 +1926,7 @@ struct regulator *_regulator_get(struct device *dev, const char *id,
 		case EXCLUSIVE_GET:
 			dev_warn(dev,
 				 "dummy supplies not allowed for exclusive requests\n");
-			/* fall through */
+			fallthrough;
 
 		default:
 			return ERR_PTR(-ENODEV);
diff --git a/drivers/regulator/slg51000-regulator.c b/drivers/regulator/slg51000-regulator.c
index 0f8041981436..75a941fb3c2b 100644
--- a/drivers/regulator/slg51000-regulator.c
+++ b/drivers/regulator/slg51000-regulator.c
@@ -319,7 +319,7 @@ static int slg51000_regulator_init(struct slg51000 *chip)
 				rdesc->linear_min_sel = 0;
 				break;
 			}
-			/* Fall through - to the check below.*/
+			fallthrough;	/* to the check below */
 
 		default:
 			rdesc->linear_min_sel = vsel_range[0];
diff --git a/drivers/regulator/twl6030-regulator.c b/drivers/regulator/twl6030-regulator.c
index f7db250a7583..430265c404d6 100644
--- a/drivers/regulator/twl6030-regulator.c
+++ b/drivers/regulator/twl6030-regulator.c
@@ -312,7 +312,7 @@ static int twl6030smps_list_voltage(struct regulator_dev *rdev, unsigned index)
 	switch (info->flags) {
 	case SMPS_OFFSET_EN:
 		voltage = 100000;
-		/* fall through */
+		fallthrough;
 	case 0:
 		switch (index) {
 		case 0: