xref: /openbmc/linux/drivers/mfd/mcp-sa11x0.c (revision 1fa6ac37)
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 
32 struct mcp_sa11x0 {
33 	u32	mccr0;
34 	u32	mccr1;
35 };
36 
37 #define priv(mcp)	((struct mcp_sa11x0 *)mcp_priv(mcp))
38 
39 static void
40 mcp_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 
51 static void
52 mcp_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  */
69 static void
70 mcp_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  */
95 static unsigned int
96 mcp_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 
117 static void mcp_sa11x0_enable(struct mcp *mcp)
118 {
119 	Ser4MCSR = -1;
120 	Ser4MCCR0 |= MCCR0_MCE;
121 }
122 
123 static void mcp_sa11x0_disable(struct mcp *mcp)
124 {
125 	Ser4MCCR0 &= ~MCCR0_MCE;
126 }
127 
128 /*
129  * Our methods.
130  */
131 static 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 
140 static 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 
210 static 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 
221 static 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 
232 static 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  */
245 MODULE_ALIAS("platform:sa11x0-mcp");
246 
247 static 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  */
260 static int __init mcp_sa11x0_init(void)
261 {
262 	return platform_driver_register(&mcp_sa11x0_driver);
263 }
264 
265 static void __exit mcp_sa11x0_exit(void)
266 {
267 	platform_driver_unregister(&mcp_sa11x0_driver);
268 }
269 
270 module_init(mcp_sa11x0_init);
271 module_exit(mcp_sa11x0_exit);
272 
273 MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
274 MODULE_DESCRIPTION("SA11x0 multimedia communications port driver");
275 MODULE_LICENSE("GPL");
276