[MFD] Add multimedia communication port core support

Add support for the core of the multimedia communication port
framework.  This is a port used to communicate with devices
with two DMA paths and a control path.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 255 insertions, 0 deletions

diff --git a/drivers/mfd/mcp-core.c b/drivers/mfd/mcp-core.c
new file mode 100644
index 000000000000..c75d713c01e4
--- /dev/null
+++ b/drivers/mfd/mcp-core.c
@@ -0,0 +1,255 @@
+/*
+ *  linux/drivers/mfd/mcp-core.c
+ *
+ *  Copyright (C) 2001 Russell King
+ *
+ * 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.
+ *
+ *  Generic MCP (Multimedia Communications Port) layer.  All MCP locking
+ *  is solely held within this file.
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/smp.h>
+#include <linux/device.h>
+
+#include <asm/dma.h>
+#include <asm/system.h>
+
+#include "mcp.h"
+
+#define to_mcp(d)		container_of(d, struct mcp, attached_device)
+#define to_mcp_driver(d)	container_of(d, struct mcp_driver, drv)
+
+static int mcp_bus_match(struct device *dev, struct device_driver *drv)
+{
+	return 1;
+}
+
+static int mcp_bus_probe(struct device *dev)
+{
+	struct mcp *mcp = to_mcp(dev);
+	struct mcp_driver *drv = to_mcp_driver(dev->driver);
+
+	return drv->probe(mcp);
+}
+
+static int mcp_bus_remove(struct device *dev)
+{
+	struct mcp *mcp = to_mcp(dev);
+	struct mcp_driver *drv = to_mcp_driver(dev->driver);
+
+	drv->remove(mcp);
+	return 0;
+}
+
+static int mcp_bus_suspend(struct device *dev, pm_message_t state)
+{
+	struct mcp *mcp = to_mcp(dev);
+	int ret = 0;
+
+	if (dev->driver) {
+		struct mcp_driver *drv = to_mcp_driver(dev->driver);
+
+		ret = drv->suspend(mcp, state);
+	}
+	return ret;
+}
+
+static int mcp_bus_resume(struct device *dev)
+{
+	struct mcp *mcp = to_mcp(dev);
+	int ret = 0;
+
+	if (dev->driver) {
+		struct mcp_driver *drv = to_mcp_driver(dev->driver);
+
+		ret = drv->resume(mcp);
+	}
+	return ret;
+}
+
+static struct bus_type mcp_bus_type = {
+	.name		= "mcp",
+	.match		= mcp_bus_match,
+	.suspend	= mcp_bus_suspend,
+	.resume		= mcp_bus_resume,
+};
+
+/**
+ *	mcp_set_telecom_divisor - set the telecom divisor
+ *	@mcp: MCP interface structure
+ *	@div: SIB clock divisor
+ *
+ *	Set the telecom divisor on the MCP interface.  The resulting
+ *	sample rate is SIBCLOCK/div.
+ */
+void mcp_set_telecom_divisor(struct mcp *mcp, unsigned int div)
+{
+	spin_lock_irq(&mcp->lock);
+	mcp->ops->set_telecom_divisor(mcp, div);
+	spin_unlock_irq(&mcp->lock);
+}
+EXPORT_SYMBOL(mcp_set_telecom_divisor);
+
+/**
+ *	mcp_set_audio_divisor - set the audio divisor
+ *	@mcp: MCP interface structure
+ *	@div: SIB clock divisor
+ *
+ *	Set the audio divisor on the MCP interface.
+ */
+void mcp_set_audio_divisor(struct mcp *mcp, unsigned int div)
+{
+	spin_lock_irq(&mcp->lock);
+	mcp->ops->set_audio_divisor(mcp, div);
+	spin_unlock_irq(&mcp->lock);
+}
+EXPORT_SYMBOL(mcp_set_audio_divisor);
+
+/**
+ *	mcp_reg_write - write a device register
+ *	@mcp: MCP interface structure
+ *	@reg: 4-bit register index
+ *	@val: 16-bit data value
+ *
+ *	Write a device register.  The MCP interface must be enabled
+ *	to prevent this function hanging.
+ */
+void mcp_reg_write(struct mcp *mcp, unsigned int reg, unsigned int val)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&mcp->lock, flags);
+	mcp->ops->reg_write(mcp, reg, val);
+	spin_unlock_irqrestore(&mcp->lock, flags);
+}
+EXPORT_SYMBOL(mcp_reg_write);
+
+/**
+ *	mcp_reg_read - read a device register
+ *	@mcp: MCP interface structure
+ *	@reg: 4-bit register index
+ *
+ *	Read a device register and return its value.  The MCP interface
+ *	must be enabled to prevent this function hanging.
+ */
+unsigned int mcp_reg_read(struct mcp *mcp, unsigned int reg)
+{
+	unsigned long flags;
+	unsigned int val;
+
+	spin_lock_irqsave(&mcp->lock, flags);
+	val = mcp->ops->reg_read(mcp, reg);
+	spin_unlock_irqrestore(&mcp->lock, flags);
+
+	return val;
+}
+EXPORT_SYMBOL(mcp_reg_read);
+
+/**
+ *	mcp_enable - enable the MCP interface
+ *	@mcp: MCP interface to enable
+ *
+ *	Enable the MCP interface.  Each call to mcp_enable will need
+ *	a corresponding call to mcp_disable to disable the interface.
+ */
+void mcp_enable(struct mcp *mcp)
+{
+	spin_lock_irq(&mcp->lock);
+	if (mcp->use_count++ == 0)
+		mcp->ops->enable(mcp);
+	spin_unlock_irq(&mcp->lock);
+}
+EXPORT_SYMBOL(mcp_enable);
+
+/**
+ *	mcp_disable - disable the MCP interface
+ *	@mcp: MCP interface to disable
+ *
+ *	Disable the MCP interface.  The MCP interface will only be
+ *	disabled once the number of calls to mcp_enable matches the
+ *	number of calls to mcp_disable.
+ */
+void mcp_disable(struct mcp *mcp)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&mcp->lock, flags);
+	if (--mcp->use_count == 0)
+		mcp->ops->disable(mcp);
+	spin_unlock_irqrestore(&mcp->lock, flags);
+}
+EXPORT_SYMBOL(mcp_disable);
+
+static void mcp_release(struct device *dev)
+{
+	struct mcp *mcp = container_of(dev, struct mcp, attached_device);
+
+	kfree(mcp);
+}
+
+struct mcp *mcp_host_alloc(struct device *parent, size_t size)
+{
+	struct mcp *mcp;
+
+	mcp = kmalloc(sizeof(struct mcp) + size, GFP_KERNEL);
+	if (mcp) {
+		memset(mcp, 0, sizeof(struct mcp) + size);
+		spin_lock_init(&mcp->lock);
+		mcp->attached_device.parent = parent;
+		mcp->attached_device.bus = &mcp_bus_type;
+		mcp->attached_device.dma_mask = parent->dma_mask;
+		mcp->attached_device.release = mcp_release;
+	}
+	return mcp;
+}
+EXPORT_SYMBOL(mcp_host_alloc);
+
+int mcp_host_register(struct mcp *mcp)
+{
+	strcpy(mcp->attached_device.bus_id, "mcp0");
+	return device_register(&mcp->attached_device);
+}
+EXPORT_SYMBOL(mcp_host_register);
+
+void mcp_host_unregister(struct mcp *mcp)
+{
+	device_unregister(&mcp->attached_device);
+}
+EXPORT_SYMBOL(mcp_host_unregister);
+
+int mcp_driver_register(struct mcp_driver *mcpdrv)
+{
+	mcpdrv->drv.bus = &mcp_bus_type;
+	mcpdrv->drv.probe = mcp_bus_probe;
+	mcpdrv->drv.remove = mcp_bus_remove;
+	return driver_register(&mcpdrv->drv);
+}
+EXPORT_SYMBOL(mcp_driver_register);
+
+void mcp_driver_unregister(struct mcp_driver *mcpdrv)
+{
+	driver_unregister(&mcpdrv->drv);
+}
+EXPORT_SYMBOL(mcp_driver_unregister);
+
+static int __init mcp_init(void)
+{
+	return bus_register(&mcp_bus_type);
+}
+
+static void __exit mcp_exit(void)
+{
+	bus_unregister(&mcp_bus_type);
+}
+
+module_init(mcp_init);
+module_exit(mcp_exit);
+
+MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
+MODULE_DESCRIPTION("Core multimedia communications port driver");
+MODULE_LICENSE("GPL");