mfd: Factor out WM831x I2C I/O from the core driver

In preparation for the addition of SPI support for the WM831x move the I2C
specific code into a separate file with a separate Kconfig option so the
I2C support can be excluded from the build.

Also update the 1133-EV1 PMIC module support for SMDK6410 to use the new
symbol.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

arch/arm/mach-s3c64xx/Kconfig

@@ -185,6 +185,7 @@ config SMDK6410_WM1192_EV1
 	select REGULATOR_WM831X
 	select S3C24XX_GPIO_EXTRA64
 	select MFD_WM831X
+	select MFD_WM831X_I2C
 	help
 	  The Wolfson Microelectronics 1192-EV1 is a WM831x based PMIC
 	  daughtercard for the Samsung SMDK6410 reference platform.

drivers/mfd/Kconfig

@@ -315,14 +315,19 @@ config MFD_WM8400
 	  the functionality of the device.
 
 config MFD_WM831X
-	bool "Support Wolfson Microelectronics WM831x/2x PMICs"
+	bool
+	depends on GENERIC_HARDIRQS
+
+config MFD_WM831X_I2C
+	bool "Support Wolfson Microelectronics WM831x/2x PMICs with I2C"
 	select MFD_CORE
+	select MFD_WM831X
 	depends on I2C=y && GENERIC_HARDIRQS
 	help
-	  Support for the Wolfson Microelecronics WM831x and WM832x PMICs.
-	  This driver provides common support for accessing the device,
-	  additional drivers must be enabled in order to use the
-	  functionality of the device.
+	  Support for the Wolfson Microelecronics WM831x and WM832x PMICs
+	  when controlled using I2C.  This driver provides common support
+	  for accessing the device, additional drivers must be enabled in
+	  order to use the functionality of the device.
 
 config MFD_WM8350
 	bool

drivers/mfd/Makefile

@@ -24,6 +24,7 @@ obj-$(CONFIG_MFD_TC6393XB)	+= tc6393xb.o tmio_core.o
 obj-$(CONFIG_MFD_WM8400)	+= wm8400-core.o
 wm831x-objs			:= wm831x-core.o wm831x-irq.o wm831x-otp.o
 obj-$(CONFIG_MFD_WM831X)	+= wm831x.o
+obj-$(CONFIG_MFD_WM831X_I2C)	+= wm831x-i2c.o
 wm8350-objs			:= wm8350-core.o wm8350-regmap.o wm8350-gpio.o
 wm8350-objs			+= wm8350-irq.o
 obj-$(CONFIG_MFD_WM8350)	+= wm8350.o

drivers/mfd/wm831x-core.c

@@ -14,7 +14,6 @@
 
 #include <linux/kernel.h>
 #include <linux/module.h>
-#include <linux/i2c.h>
 #include <linux/bcd.h>
 #include <linux/delay.h>
 #include <linux/mfd/core.h>
@@ -90,15 +89,6 @@ int wm831x_isinkv_values[WM831X_ISINK_MAX_ISEL + 1] = {
 };
 EXPORT_SYMBOL_GPL(wm831x_isinkv_values);
 
-enum wm831x_parent {
-	WM8310 = 0x8310,
-	WM8311 = 0x8311,
-	WM8312 = 0x8312,
-	WM8320 = 0x8320,
-	WM8321 = 0x8321,
-	WM8325 = 0x8325,
-};
-
 static int wm831x_reg_locked(struct wm831x *wm831x, unsigned short reg)
 {
 	if (!wm831x->locked)
@@ -1447,7 +1437,7 @@ static struct mfd_cell backlight_devs[] = {
 /*
  * Instantiate the generic non-control parts of the device.
  */
-static int wm831x_device_init(struct wm831x *wm831x, unsigned long id, int irq)
+int wm831x_device_init(struct wm831x *wm831x, unsigned long id, int irq)
 {
 	struct wm831x_pdata *pdata = wm831x->dev->platform_data;
 	int rev;
@@ -1673,7 +1663,7 @@ err:
 	return ret;
 }
 
-static void wm831x_device_exit(struct wm831x *wm831x)
+void wm831x_device_exit(struct wm831x *wm831x)
 {
 	wm831x_otp_exit(wm831x);
 	mfd_remove_devices(wm831x->dev);
@@ -1683,7 +1673,7 @@ static void wm831x_device_exit(struct wm831x *wm831x)
 	kfree(wm831x);
 }
 
-static int wm831x_device_suspend(struct wm831x *wm831x)
+int wm831x_device_suspend(struct wm831x *wm831x)
 {
 	int reg, mask;
 
@@ -1719,126 +1709,6 @@ static int wm831x_device_suspend(struct wm831x *wm831x)
 	return 0;
 }
 
-static int wm831x_i2c_read_device(struct wm831x *wm831x, unsigned short reg,
-				  int bytes, void *dest)
-{
-	struct i2c_client *i2c = wm831x->control_data;
-	int ret;
-	u16 r = cpu_to_be16(reg);
-
-	ret = i2c_master_send(i2c, (unsigned char *)&r, 2);
-	if (ret < 0)
-		return ret;
-	if (ret != 2)
-		return -EIO;
-
-	ret = i2c_master_recv(i2c, dest, bytes);
-	if (ret < 0)
-		return ret;
-	if (ret != bytes)
-		return -EIO;
-	return 0;
-}
-
-/* Currently we allocate the write buffer on the stack; this is OK for
- * small writes - if we need to do large writes this will need to be
- * revised.
- */
-static int wm831x_i2c_write_device(struct wm831x *wm831x, unsigned short reg,
-				   int bytes, void *src)
-{
-	struct i2c_client *i2c = wm831x->control_data;
-	unsigned char msg[bytes + 2];
-	int ret;
-
-	reg = cpu_to_be16(reg);
-	memcpy(&msg[0], &reg, 2);
-	memcpy(&msg[2], src, bytes);
-
-	ret = i2c_master_send(i2c, msg, bytes + 2);
-	if (ret < 0)
-		return ret;
-	if (ret < bytes + 2)
-		return -EIO;
-
-	return 0;
-}
-
-static int wm831x_i2c_probe(struct i2c_client *i2c,
-			    const struct i2c_device_id *id)
-{
-	struct wm831x *wm831x;
-
-	wm831x = kzalloc(sizeof(struct wm831x), GFP_KERNEL);
-	if (wm831x == NULL)
-		return -ENOMEM;
-
-	i2c_set_clientdata(i2c, wm831x);
-	wm831x->dev = &i2c->dev;
-	wm831x->control_data = i2c;
-	wm831x->read_dev = wm831x_i2c_read_device;
-	wm831x->write_dev = wm831x_i2c_write_device;
-
-	return wm831x_device_init(wm831x, id->driver_data, i2c->irq);
-}
-
-static int wm831x_i2c_remove(struct i2c_client *i2c)
-{
-	struct wm831x *wm831x = i2c_get_clientdata(i2c);
-
-	wm831x_device_exit(wm831x);
-
-	return 0;
-}
-
-static int wm831x_i2c_suspend(struct i2c_client *i2c, pm_message_t mesg)
-{
-	struct wm831x *wm831x = i2c_get_clientdata(i2c);
-
-	return wm831x_device_suspend(wm831x);
-}
-
-static const struct i2c_device_id wm831x_i2c_id[] = {
-	{ "wm8310", WM8310 },
-	{ "wm8311", WM8311 },
-	{ "wm8312", WM8312 },
-	{ "wm8320", WM8320 },
-	{ "wm8321", WM8321 },
-	{ "wm8325", WM8325 },
-	{ }
-};
-MODULE_DEVICE_TABLE(i2c, wm831x_i2c_id);
-
-
-static struct i2c_driver wm831x_i2c_driver = {
-	.driver = {
-		   .name = "wm831x",
-		   .owner = THIS_MODULE,
-	},
-	.probe = wm831x_i2c_probe,
-	.remove = wm831x_i2c_remove,
-	.suspend = wm831x_i2c_suspend,
-	.id_table = wm831x_i2c_id,
-};
-
-static int __init wm831x_i2c_init(void)
-{
-	int ret;
-
-	ret = i2c_add_driver(&wm831x_i2c_driver);
-	if (ret != 0)
-		pr_err("Failed to register wm831x I2C driver: %d\n", ret);
-
-	return ret;
-}
-subsys_initcall(wm831x_i2c_init);
-
-static void __exit wm831x_i2c_exit(void)
-{
-	i2c_del_driver(&wm831x_i2c_driver);
-}
-module_exit(wm831x_i2c_exit);
-
-MODULE_DESCRIPTION("I2C support for the WM831X AudioPlus PMIC");
+MODULE_DESCRIPTION("Core support for the WM831X AudioPlus PMIC");
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Mark Brown");

drivers/mfd/wm831x-i2c.c

@@ -0,0 +1,143 @@
+/*
+ * wm831x-i2c.c  --  I2C access for Wolfson WM831x PMICs
+ *
+ * Copyright 2009,2010 Wolfson Microelectronics PLC.
+ *
+ * Author: Mark Brown <broonie@opensource.wolfsonmicro.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/kernel.h>
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/delay.h>
+#include <linux/mfd/core.h>
+#include <linux/slab.h>
+
+#include <linux/mfd/wm831x/core.h>
+#include <linux/mfd/wm831x/pdata.h>
+
+static int wm831x_i2c_read_device(struct wm831x *wm831x, unsigned short reg,
+				  int bytes, void *dest)
+{
+	struct i2c_client *i2c = wm831x->control_data;
+	int ret;
+	u16 r = cpu_to_be16(reg);
+
+	ret = i2c_master_send(i2c, (unsigned char *)&r, 2);
+	if (ret < 0)
+		return ret;
+	if (ret != 2)
+		return -EIO;
+
+	ret = i2c_master_recv(i2c, dest, bytes);
+	if (ret < 0)
+		return ret;
+	if (ret != bytes)
+		return -EIO;
+	return 0;
+}
+
+/* Currently we allocate the write buffer on the stack; this is OK for
+ * small writes - if we need to do large writes this will need to be
+ * revised.
+ */
+static int wm831x_i2c_write_device(struct wm831x *wm831x, unsigned short reg,
+				   int bytes, void *src)
+{
+	struct i2c_client *i2c = wm831x->control_data;
+	unsigned char msg[bytes + 2];
+	int ret;
+
+	reg = cpu_to_be16(reg);
+	memcpy(&msg[0], &reg, 2);
+	memcpy(&msg[2], src, bytes);
+
+	ret = i2c_master_send(i2c, msg, bytes + 2);
+	if (ret < 0)
+		return ret;
+	if (ret < bytes + 2)
+		return -EIO;
+
+	return 0;
+}
+
+static int wm831x_i2c_probe(struct i2c_client *i2c,
+			    const struct i2c_device_id *id)
+{
+	struct wm831x *wm831x;
+
+	wm831x = kzalloc(sizeof(struct wm831x), GFP_KERNEL);
+	if (wm831x == NULL)
+		return -ENOMEM;
+
+	i2c_set_clientdata(i2c, wm831x);
+	wm831x->dev = &i2c->dev;
+	wm831x->control_data = i2c;
+	wm831x->read_dev = wm831x_i2c_read_device;
+	wm831x->write_dev = wm831x_i2c_write_device;
+
+	return wm831x_device_init(wm831x, id->driver_data, i2c->irq);
+}
+
+static int wm831x_i2c_remove(struct i2c_client *i2c)
+{
+	struct wm831x *wm831x = i2c_get_clientdata(i2c);
+
+	wm831x_device_exit(wm831x);
+
+	return 0;
+}
+
+static int wm831x_i2c_suspend(struct i2c_client *i2c, pm_message_t mesg)
+{
+	struct wm831x *wm831x = i2c_get_clientdata(i2c);
+
+	return wm831x_device_suspend(wm831x);
+}
+
+static const struct i2c_device_id wm831x_i2c_id[] = {
+	{ "wm8310", WM8310 },
+	{ "wm8311", WM8311 },
+	{ "wm8312", WM8312 },
+	{ "wm8320", WM8320 },
+	{ "wm8321", WM8321 },
+	{ "wm8325", WM8325 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, wm831x_i2c_id);
+
+
+static struct i2c_driver wm831x_i2c_driver = {
+	.driver = {
+		   .name = "wm831x",
+		   .owner = THIS_MODULE,
+	},
+	.probe = wm831x_i2c_probe,
+	.remove = wm831x_i2c_remove,
+	.suspend = wm831x_i2c_suspend,
+	.id_table = wm831x_i2c_id,
+};
+
+static int __init wm831x_i2c_init(void)
+{
+	int ret;
+
+	ret = i2c_add_driver(&wm831x_i2c_driver);
+	if (ret != 0)
+		pr_err("Failed to register wm831x I2C driver: %d\n", ret);
+
+	return ret;
+}
+subsys_initcall(wm831x_i2c_init);
+
+static void __exit wm831x_i2c_exit(void)
+{
+	i2c_del_driver(&wm831x_i2c_driver);
+}
+module_exit(wm831x_i2c_exit);

include/linux/mfd/wm831x/core.h

@@ -238,6 +238,15 @@ struct regulator_dev;
 
 #define WM831X_NUM_IRQ_REGS 5
 
+enum wm831x_parent {
+	WM8310 = 0x8310,
+	WM8311 = 0x8311,
+	WM8312 = 0x8312,
+	WM8320 = 0x8320,
+	WM8321 = 0x8321,
+	WM8325 = 0x8325,
+};
+
 struct wm831x {
 	struct mutex io_lock;
 
@@ -285,6 +294,9 @@ int wm831x_set_bits(struct wm831x *wm831x, unsigned short reg,
 int wm831x_bulk_read(struct wm831x *wm831x, unsigned short reg,
 		     int count, u16 *buf);
 
+int wm831x_device_init(struct wm831x *wm831x, unsigned long id, int irq);
+void wm831x_device_exit(struct wm831x *wm831x);
+int wm831x_device_suspend(struct wm831x *wm831x);
 int wm831x_irq_init(struct wm831x *wm831x, int irq);
 void wm831x_irq_exit(struct wm831x *wm831x);