[PATCH v2] mfd: MAX6650/6651 support

[Laszlo Papp <lpapp@kde.org>]

MAX6650/MAX6651 chip is a multi-function device with I2C busses. The
chip includes fan-speed regulators and monitors, GPIO, and alarm.

This patch is an initial release of a MAX6650/6651 MFD driver that
supports to enable the chip with its primary I2C bus that will connect
the hwmon, and then the gpio devices for now.

Signed-off-by: Laszlo Papp <lpapp@kde.org>
---
 drivers/mfd/Kconfig                 | 11 +++++
 drivers/mfd/Makefile                |  1 +
 drivers/mfd/max665x.c               | 88 +++++++++++++++++++++++++++++++++++++
 include/linux/mfd/max665x-private.h | 42 ++++++++++++++++++
 4 files changed, 142 insertions(+)
 create mode 100644 drivers/mfd/max665x.c
 create mode 100644 include/linux/mfd/max665x-private.h

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 49bb445..e25be62 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -368,6 +368,17 @@ config MFD_MAX8907
 	  accessing the device; additional drivers must be enabled in order
 	  to use the functionality of the device.
 
+config MFD_MAX665X
+	bool "Maxim Semiconductor MAX6650/MAX6651 Support"
+	select MFD_CORE
+	depends on I2C
+	select REGMAP_I2C
+	help
+	  Say yes here to support for Maxim Semiconductor MAX6650/MAX6651. This is
+	  a fan speed regulator and monitor IC. This driver provies common support
+	  for accessing the device, additional drivers must be enabled in order to
+	  use the functionality of the device.
+
 config MFD_MAX8925
 	bool "Maxim Semiconductor MAX8925 PMIC Support"
 	depends on I2C=y
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 5aea5ef..63668c5 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -111,6 +111,7 @@ obj-$(CONFIG_MFD_DA9055)	+= da9055.o
 da9063-objs			:= da9063-core.o da9063-irq.o da9063-i2c.o
 obj-$(CONFIG_MFD_DA9063)	+= da9063.o
 
+obj-$(CONFIG_MFD_MAX665X)	+= max665x.o
 obj-$(CONFIG_MFD_MAX14577)	+= max14577.o
 obj-$(CONFIG_MFD_MAX77686)	+= max77686.o max77686-irq.o
 obj-$(CONFIG_MFD_MAX77693)	+= max77693.o max77693-irq.o
diff --git a/drivers/mfd/max665x.c b/drivers/mfd/max665x.c
new file mode 100644
index 0000000..395373fe
--- /dev/null
+++ b/drivers/mfd/max665x.c
@@ -0,0 +1,88 @@
+/*
+ * Device access for MAX6650-MAX6651
+ *
+ * Copyright(c) 2013 Polatis Ltd.
+ *
+ * Author: Laszlo Papp <laszlo.papp@polatis.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.
+ */
+
+#include <linux/device.h>
+#include <linux/mfd/core.h>
+#include <linux/module.h>
+#include <linux/i2c.h>
+
+#include <linux/mfd/max665x-private.h>
+
+static struct mfd_cell max665x_devs[] = {
+	{ .name = "max6651-gpio", },
+	{ .name = "max6650", }, /* hwmon driver */
+	{},
+};
+
+const struct regmap_config max665x_regmap_config = {
+	.reg_bits = 5,
+};
+
+static int max665x_probe(struct i2c_client *i2c,
+			    const struct i2c_device_id *id)
+{
+	struct max665x_dev *max665x;
+	int ret;
+
+	max665x = devm_kzalloc(&i2c->dev, sizeof(*max665x), GFP_KERNEL);
+	if (!max665x)
+		return -ENOMEM;
+
+	i2c_set_clientdata(i2c, max665x);
+	max665x->dev = &i2c->dev;
+	max665x->i2c = i2c;
+	max665x->map = regmap_init_i2c(i2c, &max665x_regmap_config);
+
+	mutex_init(&max665x->iolock);
+
+	ret = mfd_add_devices(max665x->dev, -1, max665x_devs,
+			ARRAY_SIZE(max665x_devs),
+			NULL, 0, NULL);
+
+	if (ret < 0)
+		dev_err(max665x->dev, "failed to register child devices\n");
+
+	return ret;
+}
+
+static int max665x_remove(struct i2c_client *i2c)
+{
+	struct max665x_dev *max665x = i2c_get_clientdata(i2c);
+
+	mfd_remove_devices(max665x->dev);
+
+	return 0;
+}
+
+static const struct i2c_device_id max665x_id[] = {
+	{ "max6650", TYPE_MAX6650 },
+	{ "max6651", TYPE_MAX6651 },
+	{},
+};
+MODULE_DEVICE_TABLE(i2c, max665x_id);
+
+static struct i2c_driver max665x_driver = {
+	.driver = {
+		.name = "max665x",
+		.owner = THIS_MODULE,
+	},
+	.probe = max665x_probe,
+	.remove = max665x_remove,
+	.id_table = max665x_id,
+};
+
+module_i2c_driver(max665x_driver);
+
+MODULE_AUTHOR("Laszlo Papp <laszlo.papp@polatis.com>");
+MODULE_DESCRIPTION("MAX6650-MAX6651 MFD");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/mfd/max665x-private.h b/include/linux/mfd/max665x-private.h
new file mode 100644
index 0000000..92da00c
--- /dev/null
+++ b/include/linux/mfd/max665x-private.h
@@ -0,0 +1,42 @@
+/*
+ * max665x-private.h - Driver for the Maxim 6650/6651
+ *
+ * Copyright 2013 Polatis Ltd.
+ *
+ * Author: Milo Kim <laszlo.papp@polatis.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.
+ *
+ */
+
+#ifndef __LINUX_MFD_MAX665X_PRIVATE_H
+#define __LINUX_MFD_MAX665X_PRIVATE_H
+
+#include <linux/i2c.h>
+#include <linux/export.h>
+#include <linux/regmap.h>
+
+struct max665x_dev {
+	struct device *dev;
+	struct mutex iolock;
+
+	struct i2c_client *i2c;
+	struct regmap     *map;
+
+	int type;
+};
+
+enum max665x_types {
+	TYPE_MAX6650,
+	TYPE_MAX6651,
+};
+
+#endif
-- 
1.8.5.4