xref: /openbmc/linux/drivers/mfd/mcp-sa11x0.c (revision a09d2831)
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/slab.h>
21 #include <linux/platform_device.h>
22 #include <linux/mfd/mcp.h>
23 
24 #include <mach/dma.h>
25 #include <mach/hardware.h>
26 #include <asm/mach-types.h>
27 #include <asm/system.h>
28 #include <mach/mcp.h>
29 
30 #include <mach/assabet.h>
31 
32 
33 struct mcp_sa11x0 {
34 	u32	mccr0;
35 	u32	mccr1;
36 };
37 
38 #define priv(mcp)	((struct mcp_sa11x0 *)mcp_priv(mcp))
39 
40 static void
41 mcp_sa11x0_set_telecom_divisor(struct mcp *mcp, unsigned int divisor)
42 {
43 	unsigned int mccr0;
44 
45 	divisor /= 32;
46 
47 	mccr0 = Ser4MCCR0 & ~0x00007f00;
48 	mccr0 |= divisor << 8;
49 	Ser4MCCR0 = mccr0;
50 }
51 
52 static void
53 mcp_sa11x0_set_audio_divisor(struct mcp *mcp, unsigned int divisor)
54 {
55 	unsigned int mccr0;
56 
57 	divisor /= 32;
58 
59 	mccr0 = Ser4MCCR0 & ~0x0000007f;
60 	mccr0 |= divisor;
61 	Ser4MCCR0 = mccr0;
62 }
63 
64 /*
65  * Write data to the device.  The bit should be set after 3 subframe
66  * times (each frame is 64 clocks).  We wait a maximum of 6 subframes.
67  * We really should try doing something more productive while we
68  * wait.
69  */
70 static void
71 mcp_sa11x0_write(struct mcp *mcp, unsigned int reg, unsigned int val)
72 {
73 	int ret = -ETIME;
74 	int i;
75 
76 	Ser4MCDR2 = reg << 17 | MCDR2_Wr | (val & 0xffff);
77 
78 	for (i = 0; i < 2; i++) {
79 		udelay(mcp->rw_timeout);
80 		if (Ser4MCSR & MCSR_CWC) {
81 			ret = 0;
82 			break;
83 		}
84 	}
85 
86 	if (ret < 0)
87 		printk(KERN_WARNING "mcp: write timed out\n");
88 }
89 
90 /*
91  * Read data from the device.  The bit should be set after 3 subframe
92  * times (each frame is 64 clocks).  We wait a maximum of 6 subframes.
93  * We really should try doing something more productive while we
94  * wait.
95  */
96 static unsigned int
97 mcp_sa11x0_read(struct mcp *mcp, unsigned int reg)
98 {
99 	int ret = -ETIME;
100 	int i;
101 
102 	Ser4MCDR2 = reg << 17 | MCDR2_Rd;
103 
104 	for (i = 0; i < 2; i++) {
105 		udelay(mcp->rw_timeout);
106 		if (Ser4MCSR & MCSR_CRC) {
107 			ret = Ser4MCDR2 & 0xffff;
108 			break;
109 		}
110 	}
111 
112 	if (ret < 0)
113 		printk(KERN_WARNING "mcp: read timed out\n");
114 
115 	return ret;
116 }
117 
118 static void mcp_sa11x0_enable(struct mcp *mcp)
119 {
120 	Ser4MCSR = -1;
121 	Ser4MCCR0 |= MCCR0_MCE;
122 }
123 
124 static void mcp_sa11x0_disable(struct mcp *mcp)
125 {
126 	Ser4MCCR0 &= ~MCCR0_MCE;
127 }
128 
129 /*
130  * Our methods.
131  */
132 static struct mcp_ops mcp_sa11x0 = {
133 	.set_telecom_divisor	= mcp_sa11x0_set_telecom_divisor,
134 	.set_audio_divisor	= mcp_sa11x0_set_audio_divisor,
135 	.reg_write		= mcp_sa11x0_write,
136 	.reg_read		= mcp_sa11x0_read,
137 	.enable			= mcp_sa11x0_enable,
138 	.disable		= mcp_sa11x0_disable,
139 };
140 
141 static int mcp_sa11x0_probe(struct platform_device *pdev)
142 {
143 	struct mcp_plat_data *data = pdev->dev.platform_data;
144 	struct mcp *mcp;
145 	int ret;
146 
147 	if (!data)
148 		return -ENODEV;
149 
150 	if (!request_mem_region(0x80060000, 0x60, "sa11x0-mcp"))
151 		return -EBUSY;
152 
153 	mcp = mcp_host_alloc(&pdev->dev, sizeof(struct mcp_sa11x0));
154 	if (!mcp) {
155 		ret = -ENOMEM;
156 		goto release;
157 	}
158 
159 	mcp->owner		= THIS_MODULE;
160 	mcp->ops		= &mcp_sa11x0;
161 	mcp->sclk_rate		= data->sclk_rate;
162 	mcp->dma_audio_rd	= DMA_Ser4MCP0Rd;
163 	mcp->dma_audio_wr	= DMA_Ser4MCP0Wr;
164 	mcp->dma_telco_rd	= DMA_Ser4MCP1Rd;
165 	mcp->dma_telco_wr	= DMA_Ser4MCP1Wr;
166 	mcp->gpio_base		= data->gpio_base;
167 
168 	platform_set_drvdata(pdev, mcp);
169 
170 	if (machine_is_assabet()) {
171 		ASSABET_BCR_set(ASSABET_BCR_CODEC_RST);
172 	}
173 
174 	/*
175 	 * Setup the PPC unit correctly.
176 	 */
177 	PPDR &= ~PPC_RXD4;
178 	PPDR |= PPC_TXD4 | PPC_SCLK | PPC_SFRM;
179 	PSDR |= PPC_RXD4;
180 	PSDR &= ~(PPC_TXD4 | PPC_SCLK | PPC_SFRM);
181 	PPSR &= ~(PPC_TXD4 | PPC_SCLK | PPC_SFRM);
182 
183 	/*
184 	 * Initialise device.  Note that we initially
185 	 * set the sampling rate to minimum.
186 	 */
187 	Ser4MCSR = -1;
188 	Ser4MCCR1 = data->mccr1;
189 	Ser4MCCR0 = data->mccr0 | 0x7f7f;
190 
191 	/*
192 	 * Calculate the read/write timeout (us) from the bit clock
193 	 * rate.  This is the period for 3 64-bit frames.  Always
194 	 * round this time up.
195 	 */
196 	mcp->rw_timeout = (64 * 3 * 1000000 + mcp->sclk_rate - 1) /
197 			  mcp->sclk_rate;
198 
199 	ret = mcp_host_register(mcp);
200 	if (ret == 0)
201 		goto out;
202 
203  release:
204 	release_mem_region(0x80060000, 0x60);
205 	platform_set_drvdata(pdev, NULL);
206 
207  out:
208 	return ret;
209 }
210 
211 static int mcp_sa11x0_remove(struct platform_device *dev)
212 {
213 	struct mcp *mcp = platform_get_drvdata(dev);
214 
215 	platform_set_drvdata(dev, NULL);
216 	mcp_host_unregister(mcp);
217 	release_mem_region(0x80060000, 0x60);
218 
219 	return 0;
220 }
221 
222 static int mcp_sa11x0_suspend(struct platform_device *dev, pm_message_t state)
223 {
224 	struct mcp *mcp = platform_get_drvdata(dev);
225 
226 	priv(mcp)->mccr0 = Ser4MCCR0;
227 	priv(mcp)->mccr1 = Ser4MCCR1;
228 	Ser4MCCR0 &= ~MCCR0_MCE;
229 
230 	return 0;
231 }
232 
233 static int mcp_sa11x0_resume(struct platform_device *dev)
234 {
235 	struct mcp *mcp = platform_get_drvdata(dev);
236 
237 	Ser4MCCR1 = priv(mcp)->mccr1;
238 	Ser4MCCR0 = priv(mcp)->mccr0;
239 
240 	return 0;
241 }
242 
243 /*
244  * The driver for the SA11x0 MCP port.
245  */
246 MODULE_ALIAS("platform:sa11x0-mcp");
247 
248 static struct platform_driver mcp_sa11x0_driver = {
249 	.probe		= mcp_sa11x0_probe,
250 	.remove		= mcp_sa11x0_remove,
251 	.suspend	= mcp_sa11x0_suspend,
252 	.resume		= mcp_sa11x0_resume,
253 	.driver		= {
254 		.name	= "sa11x0-mcp",
255 	},
256 };
257 
258 /*
259  * This needs re-working
260  */
261 static int __init mcp_sa11x0_init(void)
262 {
263 	return platform_driver_register(&mcp_sa11x0_driver);
264 }
265 
266 static void __exit mcp_sa11x0_exit(void)
267 {
268 	platform_driver_unregister(&mcp_sa11x0_driver);
269 }
270 
271 module_init(mcp_sa11x0_init);
272 module_exit(mcp_sa11x0_exit);
273 
274 MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
275 MODULE_DESCRIPTION("SA11x0 multimedia communications port driver");
276 MODULE_LICENSE("GPL");
277