mcp-sa11x0.c revision 5a0e3ad6af8660be21ca98a971cd00f331318c05 
1/*
2 *  linux/drivers/mfd/mcp-sa11x0.c
3 *
4 *  Copyright (C) 2001-2005 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 *  SA11x0 MCP (Multimedia Communications Port) driver.
11 *
12 *  MCP read/write timeouts from Jordi Colomer, rehacked by rmk.
13 */
14#include <linux/module.h>
15#include <linux/init.h>
16#include <linux/errno.h>
17#include <linux/kernel.h>
18#include <linux/delay.h>
19#include <linux/spinlock.h>
20#include <linux/platform_device.h>
21#include <linux/mfd/mcp.h>
22
23#include <mach/dma.h>
24#include <mach/hardware.h>
25#include <asm/mach-types.h>
26#include <asm/system.h>
27#include <mach/mcp.h>
28
29#include <mach/assabet.h>
30
31
32struct mcp_sa11x0 {
33	u32	mccr0;
34	u32	mccr1;
35};
36
37#define priv(mcp)	((struct mcp_sa11x0 *)mcp_priv(mcp))
38
39static void
40mcp_sa11x0_set_telecom_divisor(struct mcp *mcp, unsigned int divisor)
41{
42	unsigned int mccr0;
43
44	divisor /= 32;
45
46	mccr0 = Ser4MCCR0 & ~0x00007f00;
47	mccr0 |= divisor << 8;
48	Ser4MCCR0 = mccr0;
49}
50
51static void
52mcp_sa11x0_set_audio_divisor(struct mcp *mcp, unsigned int divisor)
53{
54	unsigned int mccr0;
55
56	divisor /= 32;
57
58	mccr0 = Ser4MCCR0 & ~0x0000007f;
59	mccr0 |= divisor;
60	Ser4MCCR0 = mccr0;
61}
62
63/*
64 * Write data to the device.  The bit should be set after 3 subframe
65 * times (each frame is 64 clocks).  We wait a maximum of 6 subframes.
66 * We really should try doing something more productive while we
67 * wait.
68 */
69static void
70mcp_sa11x0_write(struct mcp *mcp, unsigned int reg, unsigned int val)
71{
72	int ret = -ETIME;
73	int i;
74
75	Ser4MCDR2 = reg << 17 | MCDR2_Wr | (val & 0xffff);
76
77	for (i = 0; i < 2; i++) {
78		udelay(mcp->rw_timeout);
79		if (Ser4MCSR & MCSR_CWC) {
80			ret = 0;
81			break;
82		}
83	}
84
85	if (ret < 0)
86		printk(KERN_WARNING "mcp: write timed out\n");
87}
88
89/*
90 * Read data from the device.  The bit should be set after 3 subframe
91 * times (each frame is 64 clocks).  We wait a maximum of 6 subframes.
92 * We really should try doing something more productive while we
93 * wait.
94 */
95static unsigned int
96mcp_sa11x0_read(struct mcp *mcp, unsigned int reg)
97{
98	int ret = -ETIME;
99	int i;
100
101	Ser4MCDR2 = reg << 17 | MCDR2_Rd;
102
103	for (i = 0; i < 2; i++) {
104		udelay(mcp->rw_timeout);
105		if (Ser4MCSR & MCSR_CRC) {
106			ret = Ser4MCDR2 & 0xffff;
107			break;
108		}
109	}
110
111	if (ret < 0)
112		printk(KERN_WARNING "mcp: read timed out\n");
113
114	return ret;
115}
116
117static void mcp_sa11x0_enable(struct mcp *mcp)
118{
119	Ser4MCSR = -1;
120	Ser4MCCR0 |= MCCR0_MCE;
121}
122
123static void mcp_sa11x0_disable(struct mcp *mcp)
124{
125	Ser4MCCR0 &= ~MCCR0_MCE;
126}
127
128/*
129 * Our methods.
130 */
131static struct mcp_ops mcp_sa11x0 = {
132	.set_telecom_divisor	= mcp_sa11x0_set_telecom_divisor,
133	.set_audio_divisor	= mcp_sa11x0_set_audio_divisor,
134	.reg_write		= mcp_sa11x0_write,
135	.reg_read		= mcp_sa11x0_read,
136	.enable			= mcp_sa11x0_enable,
137	.disable		= mcp_sa11x0_disable,
138};
139
140static int mcp_sa11x0_probe(struct platform_device *pdev)
141{
142	struct mcp_plat_data *data = pdev->dev.platform_data;
143	struct mcp *mcp;
144	int ret;
145
146	if (!data)
147		return -ENODEV;
148
149	if (!request_mem_region(0x80060000, 0x60, "sa11x0-mcp"))
150		return -EBUSY;
151
152	mcp = mcp_host_alloc(&pdev->dev, sizeof(struct mcp_sa11x0));
153	if (!mcp) {
154		ret = -ENOMEM;
155		goto release;
156	}
157
158	mcp->owner		= THIS_MODULE;
159	mcp->ops		= &mcp_sa11x0;
160	mcp->sclk_rate		= data->sclk_rate;
161	mcp->dma_audio_rd	= DMA_Ser4MCP0Rd;
162	mcp->dma_audio_wr	= DMA_Ser4MCP0Wr;
163	mcp->dma_telco_rd	= DMA_Ser4MCP1Rd;
164	mcp->dma_telco_wr	= DMA_Ser4MCP1Wr;
165	mcp->gpio_base		= data->gpio_base;
166
167	platform_set_drvdata(pdev, mcp);
168
169	if (machine_is_assabet()) {
170		ASSABET_BCR_set(ASSABET_BCR_CODEC_RST);
171	}
172
173	/*
174	 * Setup the PPC unit correctly.
175	 */
176	PPDR &= ~PPC_RXD4;
177	PPDR |= PPC_TXD4 | PPC_SCLK | PPC_SFRM;
178	PSDR |= PPC_RXD4;
179	PSDR &= ~(PPC_TXD4 | PPC_SCLK | PPC_SFRM);
180	PPSR &= ~(PPC_TXD4 | PPC_SCLK | PPC_SFRM);
181
182	/*
183	 * Initialise device.  Note that we initially
184	 * set the sampling rate to minimum.
185	 */
186	Ser4MCSR = -1;
187	Ser4MCCR1 = data->mccr1;
188	Ser4MCCR0 = data->mccr0 | 0x7f7f;
189
190	/*
191	 * Calculate the read/write timeout (us) from the bit clock
192	 * rate.  This is the period for 3 64-bit frames.  Always
193	 * round this time up.
194	 */
195	mcp->rw_timeout = (64 * 3 * 1000000 + mcp->sclk_rate - 1) /
196			  mcp->sclk_rate;
197
198	ret = mcp_host_register(mcp);
199	if (ret == 0)
200		goto out;
201
202 release:
203	release_mem_region(0x80060000, 0x60);
204	platform_set_drvdata(pdev, NULL);
205
206 out:
207	return ret;
208}
209
210static int mcp_sa11x0_remove(struct platform_device *dev)
211{
212	struct mcp *mcp = platform_get_drvdata(dev);
213
214	platform_set_drvdata(dev, NULL);
215	mcp_host_unregister(mcp);
216	release_mem_region(0x80060000, 0x60);
217
218	return 0;
219}
220
221static int mcp_sa11x0_suspend(struct platform_device *dev, pm_message_t state)
222{
223	struct mcp *mcp = platform_get_drvdata(dev);
224
225	priv(mcp)->mccr0 = Ser4MCCR0;
226	priv(mcp)->mccr1 = Ser4MCCR1;
227	Ser4MCCR0 &= ~MCCR0_MCE;
228
229	return 0;
230}
231
232static int mcp_sa11x0_resume(struct platform_device *dev)
233{
234	struct mcp *mcp = platform_get_drvdata(dev);
235
236	Ser4MCCR1 = priv(mcp)->mccr1;
237	Ser4MCCR0 = priv(mcp)->mccr0;
238
239	return 0;
240}
241
242/*
243 * The driver for the SA11x0 MCP port.
244 */
245MODULE_ALIAS("platform:sa11x0-mcp");
246
247static struct platform_driver mcp_sa11x0_driver = {
248	.probe		= mcp_sa11x0_probe,
249	.remove		= mcp_sa11x0_remove,
250	.suspend	= mcp_sa11x0_suspend,
251	.resume		= mcp_sa11x0_resume,
252	.driver		= {
253		.name	= "sa11x0-mcp",
254	},
255};
256
257/*
258 * This needs re-working
259 */
260static int __init mcp_sa11x0_init(void)
261{
262	return platform_driver_register(&mcp_sa11x0_driver);
263}
264
265static void __exit mcp_sa11x0_exit(void)
266{
267	platform_driver_unregister(&mcp_sa11x0_driver);
268}
269
270module_init(mcp_sa11x0_init);
271module_exit(mcp_sa11x0_exit);
272
273MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
274MODULE_DESCRIPTION("SA11x0 multimedia communications port driver");
275MODULE_LICENSE("GPL");
276