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>
22 #include <asm/system.h>
26 #define to_mcp(d) container_of(d, struct mcp, attached_device)
27 #define to_mcp_driver(d) container_of(d, struct mcp_driver, drv)
29 static int mcp_bus_match(struct device
*dev
, struct device_driver
*drv
)
34 static int mcp_bus_probe(struct device
*dev
)
36 struct mcp
*mcp
= to_mcp(dev
);
37 struct mcp_driver
*drv
= to_mcp_driver(dev
->driver
);
39 return drv
->probe(mcp
);
42 static int mcp_bus_remove(struct device
*dev
)
44 struct mcp
*mcp
= to_mcp(dev
);
45 struct mcp_driver
*drv
= to_mcp_driver(dev
->driver
);
51 static int mcp_bus_suspend(struct device
*dev
, pm_message_t state
)
53 struct mcp
*mcp
= to_mcp(dev
);
57 struct mcp_driver
*drv
= to_mcp_driver(dev
->driver
);
59 ret
= drv
->suspend(mcp
, state
);
64 static int mcp_bus_resume(struct device
*dev
)
66 struct mcp
*mcp
= to_mcp(dev
);
70 struct mcp_driver
*drv
= to_mcp_driver(dev
->driver
);
72 ret
= drv
->resume(mcp
);
77 static struct bus_type mcp_bus_type
= {
79 .match
= mcp_bus_match
,
80 .probe
= mcp_bus_probe
,
81 .remove
= mcp_bus_remove
,
82 .suspend
= mcp_bus_suspend
,
83 .resume
= mcp_bus_resume
,
87 * mcp_set_telecom_divisor - set the telecom divisor
88 * @mcp: MCP interface structure
89 * @div: SIB clock divisor
91 * Set the telecom divisor on the MCP interface. The resulting
92 * sample rate is SIBCLOCK/div.
94 void mcp_set_telecom_divisor(struct mcp
*mcp
, unsigned int div
)
96 spin_lock_irq(&mcp
->lock
);
97 mcp
->ops
->set_telecom_divisor(mcp
, div
);
98 spin_unlock_irq(&mcp
->lock
);
100 EXPORT_SYMBOL(mcp_set_telecom_divisor
);
103 * mcp_set_audio_divisor - set the audio divisor
104 * @mcp: MCP interface structure
105 * @div: SIB clock divisor
107 * Set the audio divisor on the MCP interface.
109 void mcp_set_audio_divisor(struct mcp
*mcp
, unsigned int div
)
111 spin_lock_irq(&mcp
->lock
);
112 mcp
->ops
->set_audio_divisor(mcp
, div
);
113 spin_unlock_irq(&mcp
->lock
);
115 EXPORT_SYMBOL(mcp_set_audio_divisor
);
118 * mcp_reg_write - write a device register
119 * @mcp: MCP interface structure
120 * @reg: 4-bit register index
121 * @val: 16-bit data value
123 * Write a device register. The MCP interface must be enabled
124 * to prevent this function hanging.
126 void mcp_reg_write(struct mcp
*mcp
, unsigned int reg
, unsigned int val
)
130 spin_lock_irqsave(&mcp
->lock
, flags
);
131 mcp
->ops
->reg_write(mcp
, reg
, val
);
132 spin_unlock_irqrestore(&mcp
->lock
, flags
);
134 EXPORT_SYMBOL(mcp_reg_write
);
137 * mcp_reg_read - read a device register
138 * @mcp: MCP interface structure
139 * @reg: 4-bit register index
141 * Read a device register and return its value. The MCP interface
142 * must be enabled to prevent this function hanging.
144 unsigned int mcp_reg_read(struct mcp
*mcp
, unsigned int reg
)
149 spin_lock_irqsave(&mcp
->lock
, flags
);
150 val
= mcp
->ops
->reg_read(mcp
, reg
);
151 spin_unlock_irqrestore(&mcp
->lock
, flags
);
155 EXPORT_SYMBOL(mcp_reg_read
);
158 * mcp_enable - enable the MCP interface
159 * @mcp: MCP interface to enable
161 * Enable the MCP interface. Each call to mcp_enable will need
162 * a corresponding call to mcp_disable to disable the interface.
164 void mcp_enable(struct mcp
*mcp
)
166 spin_lock_irq(&mcp
->lock
);
167 if (mcp
->use_count
++ == 0)
168 mcp
->ops
->enable(mcp
);
169 spin_unlock_irq(&mcp
->lock
);
171 EXPORT_SYMBOL(mcp_enable
);
174 * mcp_disable - disable the MCP interface
175 * @mcp: MCP interface to disable
177 * Disable the MCP interface. The MCP interface will only be
178 * disabled once the number of calls to mcp_enable matches the
179 * number of calls to mcp_disable.
181 void mcp_disable(struct mcp
*mcp
)
185 spin_lock_irqsave(&mcp
->lock
, flags
);
186 if (--mcp
->use_count
== 0)
187 mcp
->ops
->disable(mcp
);
188 spin_unlock_irqrestore(&mcp
->lock
, flags
);
190 EXPORT_SYMBOL(mcp_disable
);
192 static void mcp_release(struct device
*dev
)
194 struct mcp
*mcp
= container_of(dev
, struct mcp
, attached_device
);
199 struct mcp
*mcp_host_alloc(struct device
*parent
, size_t size
)
203 mcp
= kzalloc(sizeof(struct mcp
) + size
, GFP_KERNEL
);
205 spin_lock_init(&mcp
->lock
);
206 mcp
->attached_device
.parent
= parent
;
207 mcp
->attached_device
.bus
= &mcp_bus_type
;
208 mcp
->attached_device
.dma_mask
= parent
->dma_mask
;
209 mcp
->attached_device
.release
= mcp_release
;
213 EXPORT_SYMBOL(mcp_host_alloc
);
215 int mcp_host_register(struct mcp
*mcp
)
217 strcpy(mcp
->attached_device
.bus_id
, "mcp0");
218 return device_register(&mcp
->attached_device
);
220 EXPORT_SYMBOL(mcp_host_register
);
222 void mcp_host_unregister(struct mcp
*mcp
)
224 device_unregister(&mcp
->attached_device
);
226 EXPORT_SYMBOL(mcp_host_unregister
);
228 int mcp_driver_register(struct mcp_driver
*mcpdrv
)
230 mcpdrv
->drv
.bus
= &mcp_bus_type
;
231 return driver_register(&mcpdrv
->drv
);
233 EXPORT_SYMBOL(mcp_driver_register
);
235 void mcp_driver_unregister(struct mcp_driver
*mcpdrv
)
237 driver_unregister(&mcpdrv
->drv
);
239 EXPORT_SYMBOL(mcp_driver_unregister
);
241 static int __init
mcp_init(void)
243 return bus_register(&mcp_bus_type
);
246 static void __exit
mcp_exit(void)
248 bus_unregister(&mcp_bus_type
);
251 module_init(mcp_init
);
252 module_exit(mcp_exit
);
254 MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
255 MODULE_DESCRIPTION("Core multimedia communications port driver");
256 MODULE_LICENSE("GPL");
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