extcon: palma: add vbus detection through extcon notification

Add VBUS detection on palmas and notify the state through extcon
framework.

Bug 1238096

Change-Id: Ic5bb577aa66330e93b909df7dfc297aaf55fa0e6
Signed-off-by: Mallikarjun Kasoju <mkasoju@nvidia.com>
Reviewed-on: http://git-master/r/203655
(cherry picked from commit b5e45af19fd91e8c54c17c1f21deee0afb8d6fd4)
Reviewed-on: http://git-master/r/204692
(cherry picked from commit 222d6e830ab6bb3253d18066ba5dc6f820d7a040)
Reviewed-on: http://git-master/r/206549
Reviewed-by: Automatic_Commit_Validation_User
Tested-by: Seema Khowala <seemaj@nvidia.com>
Reviewed-by: Bitan Biswas <bbiswas@nvidia.com>

3 files changed, 212 insertions, 0 deletions

diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig
index da6ff5767207..1482d27e55a9 100644
--- a/drivers/extcon/Kconfig
+++ b/drivers/extcon/Kconfig
@@ -52,6 +52,13 @@ config EXTCON_MAX8997
 	  Maxim MAX8997 PMIC. The MAX8997 MUIC is a USB port accessory
 	  detector and switch.
 
+config EXTCON_PALMAS
+	tristate "PALMAS EXTCON Support"
+	depends on MFD_PALMAS
+	help
+	 If you say yes here you get support for the VBUS detection and notification
+	 through extcon framework from Palmas PMIC.
+
 config EXTCON_ARIZONA
 	tristate "Wolfson Arizona EXTCON support"
 	depends on MFD_ARIZONA && INPUT && SND_SOC
diff --git a/drivers/extcon/Makefile b/drivers/extcon/Makefile
index 064584bdf986..fd9b31e93548 100644
--- a/drivers/extcon/Makefile
+++ b/drivers/extcon/Makefile
@@ -8,4 +8,5 @@ obj-$(CONFIG_EXTCON_ADC_JACK)	+= extcon-adc-jack.o
 obj-$(CONFIG_EXTCON_MAX77665)	+= extcon-max77665.o
 obj-$(CONFIG_EXTCON_MAX77693)	+= extcon-max77693.o
 obj-$(CONFIG_EXTCON_MAX8997)	+= extcon-max8997.o
+obj-$(CONFIG_EXTCON_PALMAS)	+= extcon-palmas.o
 obj-$(CONFIG_EXTCON_ARIZONA)	+= extcon-arizona.o
diff --git a/drivers/extcon/extcon-palmas.c b/drivers/extcon/extcon-palmas.c
new file mode 100644
index 000000000000..5977836b32de
--- /dev/null
+++ b/drivers/extcon/extcon-palmas.c
@@ -0,0 +1,204 @@
+/*
+ * palmas-extcon.c -- Palmas VBUS detection in extcon framework.
+ *
+ * Copyright (c) 2013, NVIDIA Corporation.
+ *
+ * Author: Laxman Dewangan <ldewangan@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 version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
+ * whether express or implied; 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ * 02111-1307, USA
+ */
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/pm.h>
+#include <linux/extcon.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/mfd/palmas.h>
+
+struct palmas_extcon {
+	struct device		*dev;
+	struct palmas		*palmas;
+	struct extcon_dev	*edev;
+	int			vbus_irq;
+	int			id_irq;
+};
+
+const char *palmas_excon_cable[] = {
+	[0] = "USB",
+	NULL,
+};
+
+static int palmas_extcon_cable_update(
+		struct palmas_extcon *palma_econ)
+{
+	int ret;
+	unsigned int status;
+
+	ret = palmas_read(palma_econ->palmas, PALMAS_INTERRUPT_BASE,
+				PALMAS_INT3_LINE_STATE,	&status);
+	if (ret < 0) {
+		dev_err(palma_econ->dev,
+			"INT3_LINE_STATE read failed: %d\n", ret);
+		return ret;
+	}
+
+	if (status & PALMAS_INT3_LINE_STATE_VBUS)
+		extcon_set_cable_state(palma_econ->edev, "USB", true);
+	else
+		extcon_set_cable_state(palma_econ->edev, "USB", false);
+
+	dev_info(palma_econ->dev, "VBUS %s status: 0x%02x\n",
+		(status & PALMAS_INT3_LINE_STATE_VBUS) ? "Valid" : "Invalid",
+		status);
+
+	return 0;
+}
+
+static irqreturn_t palmas_extcon_irq(int irq, void *data)
+{
+	struct palmas_extcon *palma_econ = data;
+
+	if (irq == palma_econ->vbus_irq)
+		palmas_extcon_cable_update(palma_econ);
+	else
+		dev_err(palma_econ->dev, "Unknown interrupt %d\n", irq);
+
+	return IRQ_HANDLED;
+}
+
+static int __devinit palmas_extcon_probe(struct platform_device *pdev)
+{
+	struct palmas_extcon *palma_econ;
+	struct extcon_dev *edev;
+	int ret;
+
+	palma_econ = devm_kzalloc(&pdev->dev, sizeof(*palma_econ), GFP_KERNEL);
+	if (!palma_econ) {
+		dev_err(&pdev->dev, "Memory allocation failed for palma_econ\n");
+		return -ENOMEM;
+	}
+
+	edev = devm_kzalloc(&pdev->dev, sizeof(*edev), GFP_KERNEL);
+	if (!edev) {
+		dev_err(&pdev->dev, "Memory allocation failed for edev\n");
+		return -ENOMEM;
+	}
+	palma_econ->edev = edev;
+	palma_econ->edev->name = dev_name(&pdev->dev);
+	palma_econ->edev->supported_cable = palmas_excon_cable;
+
+	palma_econ->dev = &pdev->dev;
+	palma_econ->palmas = dev_get_drvdata(pdev->dev.parent);
+	dev_set_drvdata(&pdev->dev, palma_econ);
+
+	palma_econ->vbus_irq = platform_get_irq(pdev, 0);
+	palma_econ->id_irq = platform_get_irq(pdev, 1);
+
+	ret = extcon_dev_register(palma_econ->edev, NULL);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "failed to register extcon device\n");
+		return ret;
+	}
+
+	/* Set initial state */
+	ret = palmas_extcon_cable_update(palma_econ);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Cable init failed: %d\n", ret);
+		goto out;
+	}
+
+	ret = request_threaded_irq(palma_econ->vbus_irq, NULL,
+		palmas_extcon_irq, IRQF_ONESHOT | IRQF_EARLY_RESUME,
+		dev_name(palma_econ->dev), palma_econ);
+	if (ret < 0) {
+		dev_err(palma_econ->dev, "request irq %d failed: %dn",
+			palma_econ->vbus_irq, ret);
+		goto out;
+	}
+
+	device_set_wakeup_capable(&pdev->dev, 1);
+	return 0;
+
+out:
+	extcon_dev_unregister(palma_econ->edev);
+	return ret;
+}
+
+static int __devexit palmas_extcon_remove(struct platform_device *pdev)
+{
+	struct palmas_extcon *palma_econ = dev_get_drvdata(&pdev->dev);
+
+	extcon_dev_unregister(palma_econ->edev);
+	free_irq(palma_econ->vbus_irq, palma_econ);
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int palmas_extcon_suspend(struct device *dev)
+{
+	struct palmas_extcon *palma_econ = dev_get_drvdata(dev);
+
+	if (device_may_wakeup(dev))
+		enable_irq_wake(palma_econ->vbus_irq);
+	return 0;
+}
+
+static int palmas_extcon_resume(struct device *dev)
+{
+	struct palmas_extcon *palma_econ = dev_get_drvdata(dev);
+
+	if (device_may_wakeup(dev))
+		disable_irq_wake(palma_econ->vbus_irq);
+	return 0;
+};
+#endif
+
+static const struct dev_pm_ops palmas_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(palmas_extcon_suspend,
+				palmas_extcon_resume)
+};
+
+static struct platform_driver palmas_extcon_driver = {
+	.probe = palmas_extcon_probe,
+	.remove = __devexit_p(palmas_extcon_remove),
+	.driver = {
+		.name = "palmas-extcon",
+		.owner = THIS_MODULE,
+		.pm = &palmas_pm_ops,
+	},
+};
+
+static int __init palmas_extcon_driver_init(void)
+{
+	return platform_driver_register(&palmas_extcon_driver);
+}
+subsys_initcall_sync(palmas_extcon_driver_init);
+
+static void __exit palmas_extcon_driver_exit(void)
+{
+	platform_driver_unregister(&palmas_extcon_driver);
+}
+module_exit(palmas_extcon_driver_exit);
+
+MODULE_DESCRIPTION("palmas extcon driver");
+MODULE_AUTHOR("Laxman Dewangan<ldewangan@nvidia.com>");
+MODULE_ALIAS("platform:palmas-extcon");
+MODULE_LICENSE("GPL v2");