[PATCH v4 2/3] mfd: rt5120: Add Richtek PMIC support

[cy_huang <u0084500@gmail.com>]

From: ChiYuan Huang <cy_huang@richtek.com>

Add Richtek RT5120 PMIC I2C driver.

Signed-off-by: ChiYuan Huang <cy_huang@richtek.com>
---
Since v4:
- Add "Copyright" string and refine for GPL version string.
- For the last uncertain terminated element in struct arrays, put the comma
  for it to keep the extensibility.

Since v3:
- Use a 'dev' variable and dev_err_probe to decrease the LOC in mfd.

---
 drivers/mfd/Kconfig  |  12 +++++
 drivers/mfd/Makefile |   1 +
 drivers/mfd/rt5120.c | 124 +++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 137 insertions(+)
 create mode 100644 drivers/mfd/rt5120.c

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index abb58ab..bfceece 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -1128,6 +1128,18 @@ config MFD_RT5033
 	  sub-devices like charger, fuel gauge, flash LED, current source,
 	  LDO and Buck.
 
+config MFD_RT5120
+	tristate "Richtek RT5120 Power Management IC"
+	depends on I2C
+	select MFD_CORE
+	select REGMAP_I2C
+	select REGMAP_IRQ
+	help
+	  The enables support for Richtek RT5120 PMIC. It includes four high
+	  efficiency buck converters and one LDO voltage regulator. The device
+	  is targeted at providing the CPU voltage, memory, I/O and peripheral
+	  power rails in home entertainment devices.
+
 config MFD_RC5T583
 	bool "Ricoh RC5T583 Power Management system device"
 	depends on I2C=y
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 858cacf..27e8add 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -234,6 +234,7 @@ obj-$(CONFIG_MFD_HI655X_PMIC)   += hi655x-pmic.o
 obj-$(CONFIG_MFD_DLN2)		+= dln2.o
 obj-$(CONFIG_MFD_RT4831)	+= rt4831.o
 obj-$(CONFIG_MFD_RT5033)	+= rt5033.o
+obj-$(CONFIG_MFD_RT5120)	+= rt5120.o
 obj-$(CONFIG_MFD_SKY81452)	+= sky81452.o
 
 intel-soc-pmic-objs		:= intel_soc_pmic_core.o intel_soc_pmic_crc.o
diff --git a/drivers/mfd/rt5120.c b/drivers/mfd/rt5120.c
new file mode 100644
index 00000000..8046e38
--- /dev/null
+++ b/drivers/mfd/rt5120.c
@@ -0,0 +1,124 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2022 Richtek Technology Corp.
+ * Author: ChiYuan Huang <cy_huang@richtek.com>
+ */
+
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/mfd/core.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/regmap.h>
+
+#define RT5120_REG_INTENABLE	0x1D
+#define RT5120_REG_INTSTAT	0x1E
+#define RT5120_REG_FZCMODE	0x44
+
+#define RT5120_INT_HOTDIE	0
+#define RT5120_INT_PWRKEY_REL	5
+#define RT5120_INT_PWRKEY_PRESS	6
+
+static const struct regmap_range rt5120_rd_yes_ranges[] = {
+	regmap_reg_range(0x03, 0x13),
+	regmap_reg_range(0x1c, 0x20),
+	regmap_reg_range(0x44, 0x44),
+};
+
+static const struct regmap_range rt5120_wr_yes_ranges[] = {
+	regmap_reg_range(0x06, 0x13),
+	regmap_reg_range(0x1c, 0x20),
+	regmap_reg_range(0x44, 0x44),
+};
+
+static const struct regmap_access_table rt5120_rd_table = {
+	.yes_ranges = rt5120_rd_yes_ranges,
+	.n_yes_ranges = ARRAY_SIZE(rt5120_rd_yes_ranges),
+};
+
+static const struct regmap_access_table rt5120_wr_table = {
+	.yes_ranges = rt5120_wr_yes_ranges,
+	.n_yes_ranges = ARRAY_SIZE(rt5120_wr_yes_ranges),
+};
+
+static const struct regmap_config rt5120_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.max_register = RT5120_REG_FZCMODE,
+
+	.wr_table = &rt5120_wr_table,
+	.rd_table = &rt5120_rd_table,
+};
+
+static const struct regmap_irq rt5120_irqs[] = {
+	REGMAP_IRQ_REG_LINE(RT5120_INT_HOTDIE, 8),
+	REGMAP_IRQ_REG_LINE(RT5120_INT_PWRKEY_REL, 8),
+	REGMAP_IRQ_REG_LINE(RT5120_INT_PWRKEY_PRESS, 8),
+};
+
+static const struct regmap_irq_chip rt5120_irq_chip = {
+	.name = "rt5120-pmic",
+	.status_base = RT5120_REG_INTSTAT,
+	.mask_base = RT5120_REG_INTENABLE,
+	.ack_base = RT5120_REG_INTSTAT,
+	.mask_invert = true,
+	.use_ack = true,
+	.num_regs = 1,
+	.irqs = rt5120_irqs,
+	.num_irqs = ARRAY_SIZE(rt5120_irqs),
+};
+
+static const struct resource rt5120_regulator_resources[] = {
+	DEFINE_RES_IRQ(RT5120_INT_HOTDIE),
+};
+
+static const struct resource rt5120_pwrkey_resources[] = {
+	DEFINE_RES_IRQ_NAMED(RT5120_INT_PWRKEY_PRESS, "pwrkey-press"),
+	DEFINE_RES_IRQ_NAMED(RT5120_INT_PWRKEY_REL, "pwrkey-release"),
+};
+
+static const struct mfd_cell rt5120_devs[] = {
+	MFD_CELL_RES("rt5120-regulator", rt5120_regulator_resources),
+	MFD_CELL_OF("rt5120-pwrkey", rt5120_pwrkey_resources, NULL, 0, 0, "richtek,rt5120-pwrkey"),
+};
+
+static int rt5120_probe(struct i2c_client *i2c)
+{
+	struct device *dev = &i2c->dev;
+	struct regmap *regmap;
+	struct regmap_irq_chip_data *irq_data;
+	int ret;
+
+	regmap = devm_regmap_init_i2c(i2c, &rt5120_regmap_config);
+	if (IS_ERR(regmap))
+		return dev_err_probe(dev, PTR_ERR(regmap),
+				     "Failed to init regmap\n");
+
+	ret = devm_regmap_add_irq_chip(dev, regmap, i2c->irq, IRQF_ONESHOT, 0,
+				       &rt5120_irq_chip, &irq_data);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to add IRQ chip\n");
+
+	return devm_mfd_add_devices(dev, PLATFORM_DEVID_AUTO, rt5120_devs,
+				    ARRAY_SIZE(rt5120_devs), NULL, 0,
+				    regmap_irq_get_domain(irq_data));
+}
+
+static const struct of_device_id rt5120_device_match_table[] = {
+	{ .compatible = "richtek,rt5120" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, rt5120_device_match_table);
+
+static struct i2c_driver rt5120_driver = {
+	.driver = {
+		.name = "rt5120",
+		.of_match_table = rt5120_device_match_table,
+	},
+	.probe_new = rt5120_probe,
+};
+module_i2c_driver(rt5120_driver);
+
+MODULE_AUTHOR("ChiYuan Huang <cy_huang@richtek.com>");
+MODULE_DESCRIPTION("Richtek RT5120 I2C driver");
+MODULE_LICENSE("GPL v2");
-- 
2.7.4