mfd: max14577: Add max14577 MFD driver core

This patch adds max14577 core/irq driver to support MUIC(Micro USB IC)
device and charger device and support irq domain method to control
internal interrupt of max14577 device. Also, this patch supports DT
binding with max14577_i2c_parse_dt().

The MAXIM 14577 chip contains Micro-USB Interface Circuit and Li+ Battery
Charger. It contains accessory and USB charger detection logic. It supports
USB 2.0 Hi-Speed, UART and stereo audio signals over Micro-USB connector.

The battery charger is compliant with the USB Battery Charging Specification
Revision 1.1. It has also SFOUT LDO output for powering USB devices.

Reviewed-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

1 files changed, 243 insertions, 0 deletions

diff --git a/drivers/mfd/max14577.c b/drivers/mfd/max14577.c
new file mode 100644
index 000000000000..94b766d8cb15
--- /dev/null
+++ b/drivers/mfd/max14577.c
@@ -0,0 +1,243 @@
+/*
+ * max14577.c - mfd core driver for the Maxim 14577
+ *
+ * Copyright (C) 2013 Samsung Electrnoics
+ * Chanwoo Choi <cw00.choi@samsung.com>
+ * Krzysztof Kozlowski <k.kozlowski@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that 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.
+ *
+ * This driver is based on max8997.c
+ */
+
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/max14577.h>
+#include <linux/mfd/max14577-private.h>
+
+static struct mfd_cell max14577_devs[] = {
+	{ .name = "max14577-muic", },
+	{ .name = "max14577-regulator", },
+	{ .name = "max14577-charger", },
+};
+
+static bool max14577_volatile_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case MAX14577_REG_INT1 ... MAX14577_REG_STATUS3:
+		return true;
+	default:
+		break;
+	}
+	return false;
+}
+
+static const struct regmap_config max14577_regmap_config = {
+	.reg_bits	= 8,
+	.val_bits	= 8,
+	.volatile_reg	= max14577_volatile_reg,
+	.max_register	= MAX14577_REG_END,
+};
+
+static const struct regmap_irq max14577_irqs[] = {
+	/* INT1 interrupts */
+	{ .reg_offset = 0, .mask = INT1_ADC_MASK, },
+	{ .reg_offset = 0, .mask = INT1_ADCLOW_MASK, },
+	{ .reg_offset = 0, .mask = INT1_ADCERR_MASK, },
+	/* INT2 interrupts */
+	{ .reg_offset = 1, .mask = INT2_CHGTYP_MASK, },
+	{ .reg_offset = 1, .mask = INT2_CHGDETRUN_MASK, },
+	{ .reg_offset = 1, .mask = INT2_DCDTMR_MASK, },
+	{ .reg_offset = 1, .mask = INT2_DBCHG_MASK, },
+	{ .reg_offset = 1, .mask = INT2_VBVOLT_MASK, },
+	/* INT3 interrupts */
+	{ .reg_offset = 2, .mask = INT3_EOC_MASK, },
+	{ .reg_offset = 2, .mask = INT3_CGMBC_MASK, },
+	{ .reg_offset = 2, .mask = INT3_OVP_MASK, },
+	{ .reg_offset = 2, .mask = INT3_MBCCHGERR_MASK, },
+};
+
+static const struct regmap_irq_chip max14577_irq_chip = {
+	.name			= "max14577",
+	.status_base		= MAX14577_REG_INT1,
+	.mask_base		= MAX14577_REG_INTMASK1,
+	.mask_invert		= 1,
+	.num_regs		= 3,
+	.irqs			= max14577_irqs,
+	.num_irqs		= ARRAY_SIZE(max14577_irqs),
+};
+
+static int max14577_i2c_probe(struct i2c_client *i2c,
+			      const struct i2c_device_id *id)
+{
+	struct max14577 *max14577;
+	struct max14577_platform_data *pdata = dev_get_platdata(&i2c->dev);
+	struct device_node *np = i2c->dev.of_node;
+	u8 reg_data;
+	int ret = 0;
+
+	if (np) {
+		pdata = devm_kzalloc(&i2c->dev, sizeof(*pdata), GFP_KERNEL);
+		if (!pdata)
+			return -ENOMEM;
+		i2c->dev.platform_data = pdata;
+	}
+
+	if (!pdata) {
+		dev_err(&i2c->dev, "No platform data found: %ld\n",
+				PTR_ERR(pdata));
+		return -EINVAL;
+	}
+
+	max14577 = devm_kzalloc(&i2c->dev, sizeof(*max14577), GFP_KERNEL);
+	if (!max14577)
+		return -ENOMEM;
+
+	i2c_set_clientdata(i2c, max14577);
+	max14577->dev = &i2c->dev;
+	max14577->i2c = i2c;
+	max14577->irq = i2c->irq;
+
+	max14577->regmap = devm_regmap_init_i2c(i2c, &max14577_regmap_config);
+	if (IS_ERR(max14577->regmap)) {
+		ret = PTR_ERR(max14577->regmap);
+		dev_err(max14577->dev, "Failed to allocate register map: %d\n",
+				ret);
+		return ret;
+	}
+
+	ret = max14577_read_reg(max14577->regmap, MAX14577_REG_DEVICEID,
+			&reg_data);
+	if (ret) {
+		dev_err(max14577->dev, "Device not found on this channel: %d\n",
+				ret);
+		return ret;
+	}
+	max14577->vendor_id = ((reg_data & DEVID_VENDORID_MASK) >>
+				DEVID_VENDORID_SHIFT);
+	max14577->device_id = ((reg_data & DEVID_DEVICEID_MASK) >>
+				DEVID_DEVICEID_SHIFT);
+	dev_info(max14577->dev, "Device ID: 0x%x, vendor: 0x%x\n",
+			max14577->device_id, max14577->vendor_id);
+
+	ret = regmap_add_irq_chip(max14577->regmap, max14577->irq,
+				  IRQF_TRIGGER_FALLING | IRQF_ONESHOT, 0,
+				  &max14577_irq_chip,
+				  &max14577->irq_data);
+	if (ret != 0) {
+		dev_err(&i2c->dev, "Failed to request IRQ %d: %d\n",
+				max14577->irq, ret);
+		return ret;
+	}
+
+	ret = mfd_add_devices(max14577->dev, -1, max14577_devs,
+			ARRAY_SIZE(max14577_devs), NULL, 0,
+			regmap_irq_get_domain(max14577->irq_data));
+	if (ret < 0)
+		goto err_mfd;
+
+	device_init_wakeup(max14577->dev, 1);
+
+	return 0;
+
+err_mfd:
+	regmap_del_irq_chip(max14577->irq, max14577->irq_data);
+
+	return ret;
+}
+
+static int max14577_i2c_remove(struct i2c_client *i2c)
+{
+	struct max14577 *max14577 = i2c_get_clientdata(i2c);
+
+	mfd_remove_devices(max14577->dev);
+	regmap_del_irq_chip(max14577->irq, max14577->irq_data);
+
+	return 0;
+}
+
+static const struct i2c_device_id max14577_i2c_id[] = {
+	{ "max14577", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, max14577_i2c_id);
+
+static int max14577_suspend(struct device *dev)
+{
+	struct i2c_client *i2c = container_of(dev, struct i2c_client, dev);
+	struct max14577 *max14577 = i2c_get_clientdata(i2c);
+
+	if (device_may_wakeup(dev)) {
+		enable_irq_wake(max14577->irq);
+		/*
+		 * MUIC IRQ must be disabled during suspend if this is
+		 * a wake up source because it will be handled before
+		 * resuming I2C.
+		 *
+		 * When device is woken up from suspend (e.g. by ADC change),
+		 * an interrupt occurs before resuming I2C bus controller.
+		 * Interrupt handler tries to read registers but this read
+		 * will fail because I2C is still suspended.
+		 */
+		disable_irq(max14577->irq);
+	}
+
+	return 0;
+}
+
+static int max14577_resume(struct device *dev)
+{
+	struct i2c_client *i2c = container_of(dev, struct i2c_client, dev);
+	struct max14577 *max14577 = i2c_get_clientdata(i2c);
+
+	if (device_may_wakeup(dev)) {
+		disable_irq_wake(max14577->irq);
+		enable_irq(max14577->irq);
+	}
+
+	return 0;
+}
+
+static struct of_device_id max14577_dt_match[] = {
+	{ .compatible = "maxim,max14577", },
+	{},
+};
+
+static SIMPLE_DEV_PM_OPS(max14577_pm, max14577_suspend, max14577_resume);
+
+static struct i2c_driver max14577_i2c_driver = {
+	.driver = {
+		.name = "max14577",
+		.owner = THIS_MODULE,
+		.pm = &max14577_pm,
+		.of_match_table = of_match_ptr(max14577_dt_match),
+	},
+	.probe = max14577_i2c_probe,
+	.remove = max14577_i2c_remove,
+	.id_table = max14577_i2c_id,
+};
+
+static int __init max14577_i2c_init(void)
+{
+	return i2c_add_driver(&max14577_i2c_driver);
+}
+subsys_initcall(max14577_i2c_init);
+
+static void __exit max14577_i2c_exit(void)
+{
+	i2c_del_driver(&max14577_i2c_driver);
+}
+module_exit(max14577_i2c_exit);
+
+MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>, Krzysztof Kozlowski <k.kozlowski@samsung.com>");
+MODULE_DESCRIPTION("MAXIM 14577 multi-function core driver");
+MODULE_LICENSE("GPL");