/* * 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 <linux/slab.h> #include <linux/string.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");