// SPDX-License-Identifier: GPL-2.0-only
/*
* linux/drivers/mfd/mcp-core.c
*
* Copyright (C) 2001 Russell King
*
* 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 <linux/slab.h>
#include <linux/string.h>
#include <linux/mfd/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 struct bus_type mcp_bus_type = {
.name = "mcp",
.match = mcp_bus_match,
.probe = mcp_bus_probe,
.remove = mcp_bus_remove,
};
/**
* 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)
{
unsigned long flags;
spin_lock_irqsave(&mcp->lock, flags);
mcp->ops->set_telecom_divisor(mcp, div);
spin_unlock_irqrestore(&mcp->lock, flags);
}
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)
{
unsigned long flags;
spin_lock_irqsave(&mcp->lock, flags);
mcp->ops->set_audio_divisor(mcp, div);
spin_unlock_irqrestore(&mcp->lock, flags);
}
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)
{
unsigned long flags;
spin_lock_irqsave(&mcp->lock, flags);
if (mcp->use_count++ == 0)
mcp->ops->enable(mcp);
spin_unlock_irqrestore(&mcp->lock, flags);
}
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 = kzalloc(sizeof(struct mcp) + size, GFP_KERNEL);
if (mcp) {
spin_lock_init(&mcp->lock);
device_initialize(&mcp->attached_device);
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_add(struct mcp *mcp, void *pdata)
{
mcp->attached_device.platform_data = pdata;
dev_set_name(&mcp->attached_device, "mcp0");
return device_add(&mcp->attached_device);
}
EXPORT_SYMBOL(mcp_host_add);
void mcp_host_del(struct mcp *mcp)
{
device_del(&mcp->attached_device);
}
EXPORT_SYMBOL(mcp_host_del);
void mcp_host_free(struct mcp *mcp)
{
put_device(&mcp->attached_device);
}
EXPORT_SYMBOL(mcp_host_free);
int mcp_driver_register(struct mcp_driver *mcpdrv)
{
mcpdrv->drv.bus = &mcp_bus_type;
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");
