drivers: extcon: add max77665 muic driver

MAX77665 support muic feature.

Addition of driver to support this feature.

Change-Id: Ifd0c934d2ab457e511c0a2cd1d312dba6afe8a89
Signed-off-by: Syed Rafiuddin <srafiuddin@nvidia.com>
Reviewed-on: http://git-master/r/130618
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Laxman Dewangan <ldewangan@nvidia.com>

3 files changed, 460 insertions, 0 deletions

diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig
index 7932e1bd9b02..1958bafbca35 100644
--- a/drivers/extcon/Kconfig
+++ b/drivers/extcon/Kconfig
@@ -14,4 +14,11 @@ if EXTCON
 
 comment "Extcon Device Drivers"
 
+config EXTCON_MAX77665
+	tristate "MAX77665 EXTCON Support"
+	depends on MFD_MAX77665 && EXTCON
+	help
+	 If you say yes here you get support for the MUIC device of
+	 Maxim MAX77665 PMIC.
+
 endif # MULTISTATE_SWITCH
diff --git a/drivers/extcon/Makefile b/drivers/extcon/Makefile
index 6bc69214fcd7..31365f22a0d6 100644
--- a/drivers/extcon/Makefile
+++ b/drivers/extcon/Makefile
@@ -3,3 +3,4 @@
 #
 
 obj-$(CONFIG_EXTCON)		+= extcon_class.o
+obj-$(CONFIG_EXTCON_MAX77665)	+= extcon-max77665.o
diff --git a/drivers/extcon/extcon-max77665.c b/drivers/extcon/extcon-max77665.c
new file mode 100644
index 000000000000..cfbe6352857e
--- /dev/null
+++ b/drivers/extcon/extcon-max77665.c
@@ -0,0 +1,452 @@
+/*
+ * extcon-max77665.c - MAX77665 extcon driver to support MAX77665 MUIC
+ *
+ * Copyright (C) 2012 nvidia corporation
+ * Syed Rafiuddin <srafiuddin@nvidia.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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/kobject.h>
+#include <linux/extcon.h>
+#include <linux/mfd/max77665.h>
+
+#define	DEV_NAME	"max77665-muic"
+
+#define MAX77665_MUIC_REG_ID		0x0
+#define MAX77665_MUIC_REG_INT1		0x1
+#define MAX77665_MUIC_REG_INT2		0x2
+#define MAX77665_MUIC_REG_INT3		0x3
+#define MAX77665_MUIC_REG_STATUS1	0x4
+#define MAX77665_MUIC_REG_STATUS2	0x5
+#define MAX77665_MUIC_REG_STATUS3	0x6
+#define MAX77665_MUIC_REG_INTMASK1	0x7
+#define MAX77665_MUIC_REG_INTMASK2	0x8
+#define MAX77665_MUIC_REG_INTMASK3	0x9
+#define MAX77665_MUIC_REG_CDETCTRL	0xa
+
+#define MAX77665_MUIC_REG_CONTROL1	0xc
+#define MAX77665_MUIC_REG_CONTROL2	0xd
+#define MAX77665_MUIC_REG_CONTROL3	0xe
+
+/* MAX77665-MUIC STATUS1 register */
+#define STATUS1_ADC_SHIFT		0
+#define STATUS1_ADCLOW_SHIFT		5
+#define STATUS1_ADCERR_SHIFT		6
+#define STATUS1_ADC_MASK		(0x1f << STATUS1_ADC_SHIFT)
+
+/* MAX77665-MUIC STATUS2 register */
+#define STATUS2_CHGTYP_SHIFT		0
+#define STATUS2_CHGDETRUN_SHIFT		3
+#define STATUS2_DCDTMR_SHIFT		4
+#define STATUS2_DBCHG_SHIFT		5
+#define STATUS2_VBVOLT_SHIFT		6
+#define STATUS2_CHGTYP_MASK		(0x7 << STATUS2_CHGTYP_SHIFT)
+
+/* MAX77665-MUIC CONTROL1 register */
+#define COMN1SW_SHIFT			0
+#define COMP2SW_SHIFT			3
+#define COMN1SW_MASK			(0x7 << COMN1SW_SHIFT)
+#define COMP2SW_MASK			(0x7 << COMP2SW_SHIFT)
+#define SW_MASK				(COMP2SW_MASK | COMN1SW_MASK)
+
+#define MAX77665_SW_USB		((1 << COMP2SW_SHIFT) | (1 << COMN1SW_SHIFT))
+#define MAX77665_SW_OPEN	((0 << COMP2SW_SHIFT) | (0 << COMN1SW_SHIFT))
+
+#define MAX77665_ADC_GROUND	0x00
+#define MAX77665_ADC_OPEN	0x1f
+
+enum max77665_muic_usb_type {
+	MAX77665_USB_HOST,
+	MAX77665_USB_DEVICE,
+};
+
+enum max77665_muic_charger_type {
+	MAX77665_CHARGER_TYPE_NONE = 0,
+	MAX77665_CHARGER_TYPE_USB,
+	MAX77665_CHARGER_TYPE_DOWNSTREAM_PORT,
+	MAX77665_CHARGER_TYPE_DEDICATED_CHG,
+	MAX77665_CHARGER_TYPE_500MA,
+	MAX77665_CHARGER_TYPE_1A,
+};
+
+struct max77665_muic_platform_data {
+	int irq_base;
+};
+
+struct max77665_muic {
+	struct device *dev;
+	struct max77665_muic_platform_data *muic_pdata;
+
+	int irq;
+	struct work_struct irq_work;
+
+	enum max77665_muic_charger_type pre_charger_type;
+	int pre_adc;
+
+	struct mutex mutex;
+
+	struct extcon_dev	*edev;
+};
+
+const char *max77665_extcon_cable[] = {
+	[0] = "USB",
+	[1] = "USB-Host",
+	[2] = "TA",
+	[3] = "Fast-charger",
+	[4] = "Slow-charger",
+	[5] = "Charge-downstream",
+	NULL,
+};
+
+static int max77665_read_reg(struct max77665_muic *muic,
+		uint8_t reg, uint8_t *value)
+{
+	int ret;
+	struct device *dev = muic->dev;
+
+	ret = max77665_read(dev->parent, MAX77665_I2C_SLAVE_MUIC, reg, value);
+	if (ret < 0)
+		return ret;
+	return 0;
+}
+
+static int max77665_bulk_read(struct max77665_muic *muic,
+		uint8_t reg, int count, uint8_t *buf)
+{
+	int ret;
+	struct device *dev = muic->dev;
+
+	ret = max77665_read(dev->parent, MAX77665_I2C_SLAVE_MUIC, reg, buf);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static int max77665_update_reg(struct max77665_muic *muic,
+				uint8_t reg, uint8_t value, uint8_t mask)
+{
+	int ret;
+	uint8_t read_val;
+	struct device *dev = muic->dev;
+
+	ret = max77665_read(dev->parent, MAX77665_I2C_SLAVE_MUIC,
+				reg, &read_val);
+	if (ret < 0)
+		return ret;
+
+	ret = max77665_write(dev->parent, MAX77665_I2C_SLAVE_MUIC, reg,
+			(value & mask) | (read_val & (~mask)));
+	if (ret < 0)
+		return ret;
+	return 0;
+}
+
+static int max77665_muic_handle_usb(struct max77665_muic *muic,
+			enum max77665_muic_usb_type usb_type, bool attached)
+{
+	int ret = 0;
+
+	if (usb_type == MAX77665_USB_HOST) {
+		ret = max77665_update_reg(muic, MAX77665_MUIC_REG_CONTROL1,
+				attached ? MAX77665_SW_USB : MAX77665_SW_OPEN,
+				SW_MASK);
+		if (ret) {
+			dev_err(muic->dev, "failed to update muic register\n");
+			goto out;
+		}
+	}
+
+	switch (usb_type) {
+	case MAX77665_USB_HOST:
+		extcon_set_cable_state(muic->edev, "USB-Host", attached);
+		break;
+	case MAX77665_USB_DEVICE:
+		extcon_set_cable_state(muic->edev, "USB", attached);
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+out:
+	return ret;
+}
+
+static int max77665_muic_handle_adc_detach(struct max77665_muic *muic)
+{
+	int ret = 0;
+
+	switch (muic->pre_adc) {
+	case MAX77665_ADC_GROUND:
+		ret = max77665_muic_handle_usb(muic, MAX77665_USB_HOST, false);
+		break;
+	default:
+		break;
+	}
+
+	return ret;
+}
+
+static int max77665_muic_handle_adc(struct max77665_muic *muic, int adc)
+{
+	int ret = 0;
+
+	switch (adc) {
+	case MAX77665_ADC_GROUND:
+		ret = max77665_muic_handle_usb(muic, MAX77665_USB_HOST, true);
+		break;
+	case MAX77665_ADC_OPEN:
+		ret = max77665_muic_handle_adc_detach(muic);
+		break;
+	default:
+		ret = -EINVAL;
+		goto out;
+	}
+
+	muic->pre_adc = adc;
+out:
+	return ret;
+}
+
+static int max77665_muic_handle_charger_type_detach(
+				struct max77665_muic *muic)
+{
+	int ret = 0;
+
+	switch (muic->pre_charger_type) {
+	case MAX77665_CHARGER_TYPE_USB:
+		extcon_set_cable_state(muic->edev, "USB", false);
+		break;
+	case MAX77665_CHARGER_TYPE_DOWNSTREAM_PORT:
+		extcon_set_cable_state(muic->edev, "Charge-downstream", false);
+		break;
+	case MAX77665_CHARGER_TYPE_DEDICATED_CHG:
+		extcon_set_cable_state(muic->edev, "TA", false);
+		break;
+	case MAX77665_CHARGER_TYPE_500MA:
+		extcon_set_cable_state(muic->edev, "Slow-charger", false);
+		break;
+	case MAX77665_CHARGER_TYPE_1A:
+		extcon_set_cable_state(muic->edev, "Fast-charger", false);
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
+static int max77665_muic_handle_charger_type(struct max77665_muic *muic,
+				enum max77665_muic_charger_type charger_type)
+{
+	uint8_t adc;
+	int ret;
+
+	ret = max77665_read_reg(muic, MAX77665_MUIC_REG_STATUS1, &adc);
+	if (ret) {
+		dev_err(muic->dev, "failed to read muic register\n");
+		goto out;
+	}
+
+	switch (charger_type) {
+	case MAX77665_CHARGER_TYPE_NONE:
+		ret = max77665_muic_handle_charger_type_detach(muic);
+		break;
+	case MAX77665_CHARGER_TYPE_USB:
+		if ((adc & STATUS1_ADC_MASK) == MAX77665_ADC_OPEN) {
+			max77665_muic_handle_usb(muic,
+					MAX77665_USB_DEVICE, true);
+		}
+		break;
+	case MAX77665_CHARGER_TYPE_DOWNSTREAM_PORT:
+		extcon_set_cable_state(muic->edev, "Charge-downstream", true);
+		break;
+	case MAX77665_CHARGER_TYPE_DEDICATED_CHG:
+		extcon_set_cable_state(muic->edev, "TA", true);
+		break;
+	case MAX77665_CHARGER_TYPE_500MA:
+		extcon_set_cable_state(muic->edev, "Slow-charger", true);
+		break;
+	case MAX77665_CHARGER_TYPE_1A:
+		extcon_set_cable_state(muic->edev, "Fast-charger", true);
+		break;
+	default:
+		ret = -EINVAL;
+		goto out;
+	}
+
+	muic->pre_charger_type = charger_type;
+out:
+	return ret;
+}
+
+static void max77665_muic_irq_work(struct work_struct *work)
+{
+	struct max77665_muic *muic = container_of(work,
+			struct max77665_muic, irq_work);
+	uint8_t status[2];
+	uint8_t adc, chg_type;
+
+	int ret;
+
+	mutex_lock(&muic->mutex);
+
+	ret = max77665_bulk_read(muic, MAX77665_MUIC_REG_STATUS1,
+				2, status);
+	if (ret) {
+		dev_err(muic->dev, "failed to read muic register\n");
+		mutex_unlock(&muic->mutex);
+		return;
+	}
+
+	dev_dbg(muic->dev, "%s: STATUS1:0x%x, 2:0x%x\n", __func__,
+			status[0], status[1]);
+
+	adc = status[0] & STATUS1_ADC_MASK;
+	adc >>= STATUS1_ADC_SHIFT;
+
+	chg_type = status[1] & STATUS2_CHGTYP_MASK;
+	chg_type >>= STATUS2_CHGTYP_SHIFT;
+
+	max77665_muic_handle_adc(muic, adc);
+	max77665_muic_handle_charger_type(muic, chg_type);
+
+	mutex_unlock(&muic->mutex);
+
+	return;
+}
+
+static irqreturn_t max77665_muic_irq_handler(int irq, void *data)
+{
+	struct max77665_muic *muic = data;
+
+	dev_dbg(muic->dev, "irq:%d\n", irq);
+	muic->irq = irq;
+
+	schedule_work(&muic->irq_work);
+
+	return IRQ_HANDLED;
+}
+
+static void max77665_muic_detect_dev(struct max77665_muic *muic)
+{
+	int ret;
+	uint8_t status[2], adc, chg_type;
+
+	ret = max77665_bulk_read(muic, MAX77665_MUIC_REG_STATUS1,
+				2, status);
+	if (ret) {
+		dev_err(muic->dev, "failed to read muic register\n");
+		return;
+	}
+
+	dev_info(muic->dev, "STATUS1:0x%x, STATUS2:0x%x\n",
+			status[0], status[1]);
+
+	adc = status[0] & STATUS1_ADC_MASK;
+	adc >>= STATUS1_ADC_SHIFT;
+
+	chg_type = status[1] & STATUS2_CHGTYP_MASK;
+	chg_type >>= STATUS2_CHGTYP_SHIFT;
+
+	max77665_muic_handle_adc(muic, adc);
+	max77665_muic_handle_charger_type(muic, chg_type);
+}
+
+static int __devinit max77665_muic_probe(struct platform_device *pdev)
+{
+	struct max77665_muic *muic;
+	struct max77665_muic_platform_data *pdata;
+	int ret;
+
+	pdata = dev_get_platdata(pdev->dev.parent);
+	if (!pdata) {
+		dev_err(&pdev->dev, "no platform data available\n");
+		return -ENODEV;
+	}
+
+	muic = devm_kzalloc(&pdev->dev, sizeof(struct max77665_muic),
+			GFP_KERNEL);
+	if (!muic) {
+		dev_err(&pdev->dev, "failed to allocate memory\n");
+		return -ENOMEM;
+	}
+
+	muic->dev = &pdev->dev;
+
+	platform_set_drvdata(pdev, muic);
+	mutex_init(&muic->mutex);
+	INIT_WORK(&muic->irq_work, max77665_muic_irq_work);
+
+	ret = request_threaded_irq(pdata->irq_base, NULL,
+				max77665_muic_irq_handler,
+				0, "muic_irq",
+				muic);
+	if (ret) {
+		dev_err(&pdev->dev,
+			"failed: irq request error :%d)\n", ret);
+		return ret;
+	}
+
+	/* External connector */
+	muic->edev = devm_kzalloc(&pdev->dev, sizeof(struct extcon_dev),
+			GFP_KERNEL);
+	if (!muic->edev) {
+		dev_err(&pdev->dev, "failed to allocate memory for extcon\n");
+		return -ENOMEM;
+	}
+	muic->edev->name = DEV_NAME;
+	muic->edev->supported_cable = max77665_extcon_cable;
+	ret = extcon_dev_register(muic->edev, NULL);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to register extcon device\n");
+		return ret;
+	}
+	/* Initial device detection */
+	max77665_muic_detect_dev(muic);
+
+	return 0;
+}
+
+static int __devexit max77665_muic_remove(struct platform_device *pdev)
+{
+	struct max77665_muic *muic = platform_get_drvdata(pdev);
+
+	cancel_work_sync(&muic->irq_work);
+	extcon_dev_unregister(muic->edev);
+
+	return 0;
+}
+
+static struct platform_driver max77665_muic_driver = {
+	.driver		= {
+		.name	= DEV_NAME,
+		.owner	= THIS_MODULE,
+	},
+	.probe		= max77665_muic_probe,
+	.remove		= __devexit_p(max77665_muic_remove),
+};
+
+module_platform_driver(max77665_muic_driver);
+
+MODULE_DESCRIPTION("Maxim MAX77665 Extcon driver");
+MODULE_AUTHOR("Syed Rafiuddin <srafiuddin@nvidia.com>");
+MODULE_LICENSE("GPL v2");