mfd: Add support for RICOH PMIC RC5T583

Ricoh power management IC  RC5T583 contains is multi
functional device having multiple sub devices inside this.
This device has multiple dcdc/ldo regulators, gpios, interrupt
controllers, on-key, RTCs, ADCs.
This device have 4 DCDCs, 8 LDOs, 8 GPIOs, 6 ADCs, 3 RTCs etc.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/drivers/mfd/rc5t583.c b/drivers/mfd/rc5t583.c
new file mode 100644
index 0000000..99ef944
--- /dev/null
+++ b/drivers/mfd/rc5t583.c
@@ -0,0 +1,386 @@
+/*
+ * Core driver access RC5T583 power management chip.
+ *
+ * Copyright (c) 2011-2012, NVIDIA CORPORATION.  All rights reserved.
+ * Author: Laxman dewangan <ldewangan@nvidia.com>
+ *
+ * Based on code
+ *	Copyright (C) 2011 RICOH COMPANY,LTD
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/rc5t583.h>
+#include <linux/regmap.h>
+
+#define RICOH_ONOFFSEL_REG	0x10
+#define RICOH_SWCTL_REG		0x5E
+
+struct deepsleep_control_data {
+	u8 reg_add;
+	u8 ds_pos_bit;
+};
+
+#define DEEPSLEEP_INIT(_id, _reg, _pos)		\
+	{					\
+		.reg_add = RC5T583_##_reg,	\
+		.ds_pos_bit = _pos,		\
+	}
+
+static struct deepsleep_control_data deepsleep_data[] = {
+	DEEPSLEEP_INIT(DC0, SLPSEQ1, 0),
+	DEEPSLEEP_INIT(DC1, SLPSEQ1, 4),
+	DEEPSLEEP_INIT(DC2, SLPSEQ2, 0),
+	DEEPSLEEP_INIT(DC3, SLPSEQ2, 4),
+	DEEPSLEEP_INIT(LDO0, SLPSEQ3, 0),
+	DEEPSLEEP_INIT(LDO1, SLPSEQ3, 4),
+	DEEPSLEEP_INIT(LDO2, SLPSEQ4, 0),
+	DEEPSLEEP_INIT(LDO3, SLPSEQ4, 4),
+	DEEPSLEEP_INIT(LDO4, SLPSEQ5, 0),
+	DEEPSLEEP_INIT(LDO5, SLPSEQ5, 4),
+	DEEPSLEEP_INIT(LDO6, SLPSEQ6, 0),
+	DEEPSLEEP_INIT(LDO7, SLPSEQ6, 4),
+	DEEPSLEEP_INIT(LDO8, SLPSEQ7, 0),
+	DEEPSLEEP_INIT(LDO9, SLPSEQ7, 4),
+	DEEPSLEEP_INIT(PSO0, SLPSEQ8, 0),
+	DEEPSLEEP_INIT(PSO1, SLPSEQ8, 4),
+	DEEPSLEEP_INIT(PSO2, SLPSEQ9, 0),
+	DEEPSLEEP_INIT(PSO3, SLPSEQ9, 4),
+	DEEPSLEEP_INIT(PSO4, SLPSEQ10, 0),
+	DEEPSLEEP_INIT(PSO5, SLPSEQ10, 4),
+	DEEPSLEEP_INIT(PSO6, SLPSEQ11, 0),
+	DEEPSLEEP_INIT(PSO7, SLPSEQ11, 4),
+};
+
+#define EXT_PWR_REQ		\
+	(RC5T583_EXT_PWRREQ1_CONTROL | RC5T583_EXT_PWRREQ2_CONTROL)
+
+static struct mfd_cell rc5t583_subdevs[] = {
+	{.name = "rc5t583-regulator",},
+	{.name = "rc5t583-rtc",      },
+	{.name = "rc5t583-key",      }
+};
+
+int rc5t583_write(struct device *dev, uint8_t reg, uint8_t val)
+{
+	struct rc5t583 *rc5t583 = dev_get_drvdata(dev);
+	return regmap_write(rc5t583->regmap, reg, val);
+}
+
+int rc5t583_read(struct device *dev, uint8_t reg, uint8_t *val)
+{
+	struct rc5t583 *rc5t583 = dev_get_drvdata(dev);
+	unsigned int ival;
+	int ret;
+	ret = regmap_read(rc5t583->regmap, reg, &ival);
+	if (!ret)
+		*val = (uint8_t)ival;
+	return ret;
+}
+
+int rc5t583_set_bits(struct device *dev, unsigned int reg,
+			unsigned int bit_mask)
+{
+	struct rc5t583 *rc5t583 = dev_get_drvdata(dev);
+	return regmap_update_bits(rc5t583->regmap, reg, bit_mask, bit_mask);
+}
+
+int rc5t583_clear_bits(struct device *dev, unsigned int reg,
+			unsigned int bit_mask)
+{
+	struct rc5t583 *rc5t583 = dev_get_drvdata(dev);
+	return regmap_update_bits(rc5t583->regmap, reg, bit_mask, 0);
+}
+
+int rc5t583_update(struct device *dev, unsigned int reg,
+		unsigned int val, unsigned int mask)
+{
+	struct rc5t583 *rc5t583 = dev_get_drvdata(dev);
+	return regmap_update_bits(rc5t583->regmap, reg, mask, val);
+}
+
+static int __rc5t583_set_ext_pwrreq1_control(struct device *dev,
+	int id, int ext_pwr, int slots)
+{
+	int ret;
+	uint8_t sleepseq_val;
+	unsigned int en_bit;
+	unsigned int slot_bit;
+
+	if (id == RC5T583_DS_DC0) {
+		dev_err(dev, "PWRREQ1 is invalid control for rail %d\n", id);
+		return -EINVAL;
+	}
+
+	en_bit = deepsleep_data[id].ds_pos_bit;
+	slot_bit = en_bit + 1;
+	ret = rc5t583_read(dev, deepsleep_data[id].reg_add, &sleepseq_val);
+	if (ret < 0) {
+		dev_err(dev, "Error in reading reg 0x%x\n",
+				deepsleep_data[id].reg_add);
+		return ret;
+	}
+
+	sleepseq_val &= ~(0xF << en_bit);
+	sleepseq_val |= BIT(en_bit);
+	sleepseq_val |= ((slots & 0x7) << slot_bit);
+	ret = rc5t583_set_bits(dev, RICOH_ONOFFSEL_REG, BIT(1));
+	if (ret < 0) {
+		dev_err(dev, "Error in updating the 0x%02x register\n",
+				RICOH_ONOFFSEL_REG);
+		return ret;
+	}
+
+	ret = rc5t583_write(dev, deepsleep_data[id].reg_add, sleepseq_val);
+	if (ret < 0) {
+		dev_err(dev, "Error in writing reg 0x%x\n",
+				deepsleep_data[id].reg_add);
+		return ret;
+	}
+
+	if (id == RC5T583_DS_LDO4) {
+		ret = rc5t583_write(dev, RICOH_SWCTL_REG, 0x1);
+		if (ret < 0)
+			dev_err(dev, "Error in writing reg 0x%x\n",
+				RICOH_SWCTL_REG);
+	}
+	return ret;
+}
+
+static int __rc5t583_set_ext_pwrreq2_control(struct device *dev,
+	int id, int ext_pwr)
+{
+	int ret;
+
+	if (id != RC5T583_DS_DC0) {
+		dev_err(dev, "PWRREQ2 is invalid control for rail %d\n", id);
+		return -EINVAL;
+	}
+
+	ret = rc5t583_set_bits(dev, RICOH_ONOFFSEL_REG, BIT(2));
+	if (ret < 0)
+		dev_err(dev, "Error in updating the ONOFFSEL 0x10 register\n");
+	return ret;
+}
+
+int rc5t583_ext_power_req_config(struct device *dev, int ds_id,
+	int ext_pwr_req, int deepsleep_slot_nr)
+{
+	if ((ext_pwr_req & EXT_PWR_REQ) == EXT_PWR_REQ)
+		return -EINVAL;
+
+	if (ext_pwr_req & RC5T583_EXT_PWRREQ1_CONTROL)
+		return __rc5t583_set_ext_pwrreq1_control(dev, ds_id,
+				ext_pwr_req, deepsleep_slot_nr);
+
+	if (ext_pwr_req & RC5T583_EXT_PWRREQ2_CONTROL)
+		return __rc5t583_set_ext_pwrreq2_control(dev,
+			ds_id, ext_pwr_req);
+	return 0;
+}
+
+static int rc5t583_clear_ext_power_req(struct rc5t583 *rc5t583,
+	struct rc5t583_platform_data *pdata)
+{
+	int ret;
+	int i;
+	uint8_t on_off_val = 0;
+
+	/*  Clear ONOFFSEL register */
+	if (pdata->enable_shutdown)
+		on_off_val = 0x1;
+
+	ret = rc5t583_write(rc5t583->dev, RICOH_ONOFFSEL_REG, on_off_val);
+	if (ret < 0)
+		dev_warn(rc5t583->dev, "Error in writing reg %d error: %d\n",
+					RICOH_ONOFFSEL_REG, ret);
+
+	ret = rc5t583_write(rc5t583->dev, RICOH_SWCTL_REG, 0x0);
+	if (ret < 0)
+		dev_warn(rc5t583->dev, "Error in writing reg %d error: %d\n",
+					RICOH_SWCTL_REG, ret);
+
+	/* Clear sleep sequence register */
+	for (i = RC5T583_SLPSEQ1; i <= RC5T583_SLPSEQ11; ++i) {
+		ret = rc5t583_write(rc5t583->dev, i, 0x0);
+		if (ret < 0)
+			dev_warn(rc5t583->dev,
+				"Error in writing reg 0x%02x error: %d\n",
+				i, ret);
+	}
+	return 0;
+}
+
+static bool volatile_reg(struct device *dev, unsigned int reg)
+{
+	/* Enable caching in interrupt registers */
+	switch (reg) {
+	case RC5T583_INT_EN_SYS1:
+	case RC5T583_INT_EN_SYS2:
+	case RC5T583_INT_EN_DCDC:
+	case RC5T583_INT_EN_RTC:
+	case RC5T583_INT_EN_ADC1:
+	case RC5T583_INT_EN_ADC2:
+	case RC5T583_INT_EN_ADC3:
+	case RC5T583_GPIO_GPEDGE1:
+	case RC5T583_GPIO_GPEDGE2:
+	case RC5T583_GPIO_EN_INT:
+		return false;
+
+	case RC5T583_GPIO_MON_IOIN:
+		/* This is gpio input register */
+		return true;
+
+	default:
+		/* Enable caching in gpio registers */
+		if ((reg >= RC5T583_GPIO_IOSEL) &&
+				(reg <= RC5T583_GPIO_GPOFUNC))
+			return false;
+
+		/* Enable caching in sleep seq registers */
+		if ((reg >= RC5T583_SLPSEQ1) && (reg <= RC5T583_SLPSEQ11))
+			return false;
+
+		/* Enable caching of regulator registers */
+		if ((reg >= RC5T583_REG_DC0CTL) && (reg <= RC5T583_REG_SR3CTL))
+			return false;
+		if ((reg >= RC5T583_REG_LDOEN1) &&
+					(reg <= RC5T583_REG_LDO9DAC_DS))
+			return false;
+
+		break;
+	}
+
+	return true;
+}
+
+static const struct regmap_config rc5t583_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.volatile_reg = volatile_reg,
+	.max_register = RC5T583_MAX_REGS,
+	.num_reg_defaults_raw = RC5T583_MAX_REGS,
+	.cache_type = REGCACHE_RBTREE,
+};
+
+static int __devinit rc5t583_i2c_probe(struct i2c_client *i2c,
+			      const struct i2c_device_id *id)
+{
+	struct rc5t583 *rc5t583;
+	struct rc5t583_platform_data *pdata = i2c->dev.platform_data;
+	int ret;
+	bool irq_init_success = false;
+
+	if (!pdata) {
+		dev_err(&i2c->dev, "Err: Platform data not found\n");
+		return -EINVAL;
+	}
+
+	rc5t583 = devm_kzalloc(&i2c->dev, sizeof(struct rc5t583), GFP_KERNEL);
+	if (!rc5t583) {
+		dev_err(&i2c->dev, "Memory allocation failed\n");
+		return -ENOMEM;
+	}
+
+	rc5t583->dev = &i2c->dev;
+	i2c_set_clientdata(i2c, rc5t583);
+
+	rc5t583->regmap = regmap_init_i2c(i2c, &rc5t583_regmap_config);
+	if (IS_ERR(rc5t583->regmap)) {
+		ret = PTR_ERR(rc5t583->regmap);
+		dev_err(&i2c->dev, "regmap initialization failed: %d\n", ret);
+		return ret;
+	}
+
+	ret = rc5t583_clear_ext_power_req(rc5t583, pdata);
+	if (ret < 0)
+		goto err_irq_init;
+
+	if (i2c->irq) {
+		ret = rc5t583_irq_init(rc5t583, i2c->irq, pdata->irq_base);
+		/* Still continue with waring if irq init fails */
+		if (ret)
+			dev_warn(&i2c->dev, "IRQ init failed: %d\n", ret);
+		else
+			irq_init_success = true;
+	}
+
+	ret = mfd_add_devices(rc5t583->dev, -1, rc5t583_subdevs,
+			ARRAY_SIZE(rc5t583_subdevs), NULL, 0);
+	if (ret) {
+		dev_err(&i2c->dev, "add mfd devices failed: %d\n", ret);
+		goto err_add_devs;
+	}
+
+	return 0;
+
+err_add_devs:
+	if (irq_init_success)
+		rc5t583_irq_exit(rc5t583);
+err_irq_init:
+	regmap_exit(rc5t583->regmap);
+	return ret;
+}
+
+static int  __devexit rc5t583_i2c_remove(struct i2c_client *i2c)
+{
+	struct rc5t583 *rc5t583 = i2c_get_clientdata(i2c);
+
+	mfd_remove_devices(rc5t583->dev);
+	rc5t583_irq_exit(rc5t583);
+	regmap_exit(rc5t583->regmap);
+	return 0;
+}
+
+static const struct i2c_device_id rc5t583_i2c_id[] = {
+	{.name = "rc5t583", .driver_data = 0},
+	{}
+};
+
+MODULE_DEVICE_TABLE(i2c, rc5t583_i2c_id);
+
+static struct i2c_driver rc5t583_i2c_driver = {
+	.driver = {
+		   .name = "rc5t583",
+		   .owner = THIS_MODULE,
+		   },
+	.probe = rc5t583_i2c_probe,
+	.remove = __devexit_p(rc5t583_i2c_remove),
+	.id_table = rc5t583_i2c_id,
+};
+
+static int __init rc5t583_i2c_init(void)
+{
+	return i2c_add_driver(&rc5t583_i2c_driver);
+}
+subsys_initcall(rc5t583_i2c_init);
+
+static void __exit rc5t583_i2c_exit(void)
+{
+	i2c_del_driver(&rc5t583_i2c_driver);
+}
+
+module_exit(rc5t583_i2c_exit);
+
+MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
+MODULE_DESCRIPTION("RICOH RC5T583 power management system device driver");
+MODULE_LICENSE("GPL v2");