2 * linux/drivers/mfd/mcp-core.c
4 * Copyright (C) 2001 Russell King
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.
10 * Generic MCP (Multimedia Communications Port) layer. All MCP locking
11 * is solely held within this file.
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>
25 #define to_mcp(d) container_of(d, struct mcp, attached_device)
26 #define to_mcp_driver(d) container_of(d, struct mcp_driver, drv)
28 static int mcp_bus_match(struct device *dev, struct device_driver *drv)
33 static int mcp_bus_probe(struct device *dev)
35 struct mcp *mcp = to_mcp(dev);
36 struct mcp_driver *drv = to_mcp_driver(dev->driver);
38 return drv->probe(mcp);
41 static int mcp_bus_remove(struct device *dev)
43 struct mcp *mcp = to_mcp(dev);
44 struct mcp_driver *drv = to_mcp_driver(dev->driver);
50 static int mcp_bus_suspend(struct device *dev, pm_message_t state)
52 struct mcp *mcp = to_mcp(dev);
56 struct mcp_driver *drv = to_mcp_driver(dev->driver);
58 ret = drv->suspend(mcp, state);
63 static int mcp_bus_resume(struct device *dev)
65 struct mcp *mcp = to_mcp(dev);
69 struct mcp_driver *drv = to_mcp_driver(dev->driver);
71 ret = drv->resume(mcp);
76 static struct bus_type mcp_bus_type = {
78 .match = mcp_bus_match,
79 .probe = mcp_bus_probe,
80 .remove = mcp_bus_remove,
81 .suspend = mcp_bus_suspend,
82 .resume = mcp_bus_resume,
86 * mcp_set_telecom_divisor - set the telecom divisor
87 * @mcp: MCP interface structure
88 * @div: SIB clock divisor
90 * Set the telecom divisor on the MCP interface. The resulting
91 * sample rate is SIBCLOCK/div.
93 void mcp_set_telecom_divisor(struct mcp *mcp, unsigned int div)
97 spin_lock_irqsave(&mcp->lock, flags);
98 mcp->ops->set_telecom_divisor(mcp, div);
99 spin_unlock_irqrestore(&mcp->lock, flags);
101 EXPORT_SYMBOL(mcp_set_telecom_divisor);
104 * mcp_set_audio_divisor - set the audio divisor
105 * @mcp: MCP interface structure
106 * @div: SIB clock divisor
108 * Set the audio divisor on the MCP interface.
110 void mcp_set_audio_divisor(struct mcp *mcp, unsigned int div)
114 spin_lock_irqsave(&mcp->lock, flags);
115 mcp->ops->set_audio_divisor(mcp, div);
116 spin_unlock_irqrestore(&mcp->lock, flags);
118 EXPORT_SYMBOL(mcp_set_audio_divisor);
121 * mcp_reg_write - write a device register
122 * @mcp: MCP interface structure
123 * @reg: 4-bit register index
124 * @val: 16-bit data value
126 * Write a device register. The MCP interface must be enabled
127 * to prevent this function hanging.
129 void mcp_reg_write(struct mcp *mcp, unsigned int reg, unsigned int val)
133 spin_lock_irqsave(&mcp->lock, flags);
134 mcp->ops->reg_write(mcp, reg, val);
135 spin_unlock_irqrestore(&mcp->lock, flags);
137 EXPORT_SYMBOL(mcp_reg_write);
140 * mcp_reg_read - read a device register
141 * @mcp: MCP interface structure
142 * @reg: 4-bit register index
144 * Read a device register and return its value. The MCP interface
145 * must be enabled to prevent this function hanging.
147 unsigned int mcp_reg_read(struct mcp *mcp, unsigned int reg)
152 spin_lock_irqsave(&mcp->lock, flags);
153 val = mcp->ops->reg_read(mcp, reg);
154 spin_unlock_irqrestore(&mcp->lock, flags);
158 EXPORT_SYMBOL(mcp_reg_read);
161 * mcp_enable - enable the MCP interface
162 * @mcp: MCP interface to enable
164 * Enable the MCP interface. Each call to mcp_enable will need
165 * a corresponding call to mcp_disable to disable the interface.
167 void mcp_enable(struct mcp *mcp)
170 spin_lock_irqsave(&mcp->lock, flags);
171 if (mcp->use_count++ == 0)
172 mcp->ops->enable(mcp);
173 spin_unlock_irqrestore(&mcp->lock, flags);
175 EXPORT_SYMBOL(mcp_enable);
178 * mcp_disable - disable the MCP interface
179 * @mcp: MCP interface to disable
181 * Disable the MCP interface. The MCP interface will only be
182 * disabled once the number of calls to mcp_enable matches the
183 * number of calls to mcp_disable.
185 void mcp_disable(struct mcp *mcp)
189 spin_lock_irqsave(&mcp->lock, flags);
190 if (--mcp->use_count == 0)
191 mcp->ops->disable(mcp);
192 spin_unlock_irqrestore(&mcp->lock, flags);
194 EXPORT_SYMBOL(mcp_disable);
196 static void mcp_release(struct device *dev)
198 struct mcp *mcp = container_of(dev, struct mcp, attached_device);
203 struct mcp *mcp_host_alloc(struct device *parent, size_t size)
207 mcp = kzalloc(sizeof(struct mcp) + size, GFP_KERNEL);
209 spin_lock_init(&mcp->lock);
210 mcp->attached_device.parent = parent;
211 mcp->attached_device.bus = &mcp_bus_type;
212 mcp->attached_device.dma_mask = parent->dma_mask;
213 mcp->attached_device.release = mcp_release;
217 EXPORT_SYMBOL(mcp_host_alloc);
219 int mcp_host_register(struct mcp *mcp)
221 dev_set_name(&mcp->attached_device, "mcp0");
222 return device_register(&mcp->attached_device);
224 EXPORT_SYMBOL(mcp_host_register);
226 void mcp_host_unregister(struct mcp *mcp)
228 device_unregister(&mcp->attached_device);
230 EXPORT_SYMBOL(mcp_host_unregister);
232 int mcp_driver_register(struct mcp_driver *mcpdrv)
234 mcpdrv->drv.bus = &mcp_bus_type;
235 return driver_register(&mcpdrv->drv);
237 EXPORT_SYMBOL(mcp_driver_register);
239 void mcp_driver_unregister(struct mcp_driver *mcpdrv)
241 driver_unregister(&mcpdrv->drv);
243 EXPORT_SYMBOL(mcp_driver_unregister);
245 static int __init mcp_init(void)
247 return bus_register(&mcp_bus_type);
250 static void __exit mcp_exit(void)
252 bus_unregister(&mcp_bus_type);
255 module_init(mcp_init);
256 module_exit(mcp_exit);
258 MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
259 MODULE_DESCRIPTION("Core multimedia communications port driver");
260 MODULE_LICENSE("GPL");