1/*
2 *  linux/drivers/mfd/mcp-core.c
3 *
4 *  Copyright (C) 2001 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License.
9 *
10 *  Generic MCP (Multimedia Communications Port) layer.  All MCP locking
11 *  is solely held within this file.
12 */
13#include <linux/module.h>
14#include <linux/init.h>
15#include <linux/errno.h>
16#include <linux/smp.h>
17#include <linux/device.h>
18#include <linux/slab.h>
19#include <linux/string.h>
20#include <linux/mfd/mcp.h>
21
22
23#define to_mcp(d)		container_of(d, struct mcp, attached_device)
24#define to_mcp_driver(d)	container_of(d, struct mcp_driver, drv)
25
26static int mcp_bus_match(struct device *dev, struct device_driver *drv)
27{
28	return 1;
29}
30
31static int mcp_bus_probe(struct device *dev)
32{
33	struct mcp *mcp = to_mcp(dev);
34	struct mcp_driver *drv = to_mcp_driver(dev->driver);
35
36	return drv->probe(mcp);
37}
38
39static int mcp_bus_remove(struct device *dev)
40{
41	struct mcp *mcp = to_mcp(dev);
42	struct mcp_driver *drv = to_mcp_driver(dev->driver);
43
44	drv->remove(mcp);
45	return 0;
46}
47
48static struct bus_type mcp_bus_type = {
49	.name		= "mcp",
50	.match		= mcp_bus_match,
51	.probe		= mcp_bus_probe,
52	.remove		= mcp_bus_remove,
53};
54
55/**
56 *	mcp_set_telecom_divisor - set the telecom divisor
57 *	@mcp: MCP interface structure
58 *	@div: SIB clock divisor
59 *
60 *	Set the telecom divisor on the MCP interface.  The resulting
61 *	sample rate is SIBCLOCK/div.
62 */
63void mcp_set_telecom_divisor(struct mcp *mcp, unsigned int div)
64{
65	unsigned long flags;
66
67	spin_lock_irqsave(&mcp->lock, flags);
68	mcp->ops->set_telecom_divisor(mcp, div);
69	spin_unlock_irqrestore(&mcp->lock, flags);
70}
71EXPORT_SYMBOL(mcp_set_telecom_divisor);
72
73/**
74 *	mcp_set_audio_divisor - set the audio divisor
75 *	@mcp: MCP interface structure
76 *	@div: SIB clock divisor
77 *
78 *	Set the audio divisor on the MCP interface.
79 */
80void mcp_set_audio_divisor(struct mcp *mcp, unsigned int div)
81{
82	unsigned long flags;
83
84	spin_lock_irqsave(&mcp->lock, flags);
85	mcp->ops->set_audio_divisor(mcp, div);
86	spin_unlock_irqrestore(&mcp->lock, flags);
87}
88EXPORT_SYMBOL(mcp_set_audio_divisor);
89
90/**
91 *	mcp_reg_write - write a device register
92 *	@mcp: MCP interface structure
93 *	@reg: 4-bit register index
94 *	@val: 16-bit data value
95 *
96 *	Write a device register.  The MCP interface must be enabled
97 *	to prevent this function hanging.
98 */
99void mcp_reg_write(struct mcp *mcp, unsigned int reg, unsigned int val)
100{
101	unsigned long flags;
102
103	spin_lock_irqsave(&mcp->lock, flags);
104	mcp->ops->reg_write(mcp, reg, val);
105	spin_unlock_irqrestore(&mcp->lock, flags);
106}
107EXPORT_SYMBOL(mcp_reg_write);
108
109/**
110 *	mcp_reg_read - read a device register
111 *	@mcp: MCP interface structure
112 *	@reg: 4-bit register index
113 *
114 *	Read a device register and return its value.  The MCP interface
115 *	must be enabled to prevent this function hanging.
116 */
117unsigned int mcp_reg_read(struct mcp *mcp, unsigned int reg)
118{
119	unsigned long flags;
120	unsigned int val;
121
122	spin_lock_irqsave(&mcp->lock, flags);
123	val = mcp->ops->reg_read(mcp, reg);
124	spin_unlock_irqrestore(&mcp->lock, flags);
125
126	return val;
127}
128EXPORT_SYMBOL(mcp_reg_read);
129
130/**
131 *	mcp_enable - enable the MCP interface
132 *	@mcp: MCP interface to enable
133 *
134 *	Enable the MCP interface.  Each call to mcp_enable will need
135 *	a corresponding call to mcp_disable to disable the interface.
136 */
137void mcp_enable(struct mcp *mcp)
138{
139	unsigned long flags;
140
141	spin_lock_irqsave(&mcp->lock, flags);
142	if (mcp->use_count++ == 0)
143		mcp->ops->enable(mcp);
144	spin_unlock_irqrestore(&mcp->lock, flags);
145}
146EXPORT_SYMBOL(mcp_enable);
147
148/**
149 *	mcp_disable - disable the MCP interface
150 *	@mcp: MCP interface to disable
151 *
152 *	Disable the MCP interface.  The MCP interface will only be
153 *	disabled once the number of calls to mcp_enable matches the
154 *	number of calls to mcp_disable.
155 */
156void mcp_disable(struct mcp *mcp)
157{
158	unsigned long flags;
159
160	spin_lock_irqsave(&mcp->lock, flags);
161	if (--mcp->use_count == 0)
162		mcp->ops->disable(mcp);
163	spin_unlock_irqrestore(&mcp->lock, flags);
164}
165EXPORT_SYMBOL(mcp_disable);
166
167static void mcp_release(struct device *dev)
168{
169	struct mcp *mcp = container_of(dev, struct mcp, attached_device);
170
171	kfree(mcp);
172}
173
174struct mcp *mcp_host_alloc(struct device *parent, size_t size)
175{
176	struct mcp *mcp;
177
178	mcp = kzalloc(sizeof(struct mcp) + size, GFP_KERNEL);
179	if (mcp) {
180		spin_lock_init(&mcp->lock);
181		device_initialize(&mcp->attached_device);
182		mcp->attached_device.parent = parent;
183		mcp->attached_device.bus = &mcp_bus_type;
184		mcp->attached_device.dma_mask = parent->dma_mask;
185		mcp->attached_device.release = mcp_release;
186	}
187	return mcp;
188}
189EXPORT_SYMBOL(mcp_host_alloc);
190
191int mcp_host_add(struct mcp *mcp, void *pdata)
192{
193	mcp->attached_device.platform_data = pdata;
194	dev_set_name(&mcp->attached_device, "mcp0");
195	return device_add(&mcp->attached_device);
196}
197EXPORT_SYMBOL(mcp_host_add);
198
199void mcp_host_del(struct mcp *mcp)
200{
201	device_del(&mcp->attached_device);
202}
203EXPORT_SYMBOL(mcp_host_del);
204
205void mcp_host_free(struct mcp *mcp)
206{
207	put_device(&mcp->attached_device);
208}
209EXPORT_SYMBOL(mcp_host_free);
210
211int mcp_driver_register(struct mcp_driver *mcpdrv)
212{
213	mcpdrv->drv.bus = &mcp_bus_type;
214	return driver_register(&mcpdrv->drv);
215}
216EXPORT_SYMBOL(mcp_driver_register);
217
218void mcp_driver_unregister(struct mcp_driver *mcpdrv)
219{
220	driver_unregister(&mcpdrv->drv);
221}
222EXPORT_SYMBOL(mcp_driver_unregister);
223
224static int __init mcp_init(void)
225{
226	return bus_register(&mcp_bus_type);
227}
228
229static void __exit mcp_exit(void)
230{
231	bus_unregister(&mcp_bus_type);
232}
233
234module_init(mcp_init);
235module_exit(mcp_exit);
236
237MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
238MODULE_DESCRIPTION("Core multimedia communications port driver");
239MODULE_LICENSE("GPL");
240