xref: /openbmc/linux/drivers/mfd/mcp-sa11x0.c (revision 275876e2)
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/io.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/pm.h>
22 #include <linux/mfd/mcp.h>
23 
24 #include <mach/hardware.h>
25 #include <asm/mach-types.h>
26 #include <linux/platform_data/mfd-mcp-sa11x0.h>
27 
28 #define DRIVER_NAME "sa11x0-mcp"
29 
30 struct mcp_sa11x0 {
31 	void __iomem	*base0;
32 	void __iomem	*base1;
33 	u32		mccr0;
34 	u32		mccr1;
35 };
36 
37 /* Register offsets */
38 #define MCCR0(m)	((m)->base0 + 0x00)
39 #define MCDR0(m)	((m)->base0 + 0x08)
40 #define MCDR1(m)	((m)->base0 + 0x0c)
41 #define MCDR2(m)	((m)->base0 + 0x10)
42 #define MCSR(m)		((m)->base0 + 0x18)
43 #define MCCR1(m)	((m)->base1 + 0x00)
44 
45 #define priv(mcp)	((struct mcp_sa11x0 *)mcp_priv(mcp))
46 
47 static void
48 mcp_sa11x0_set_telecom_divisor(struct mcp *mcp, unsigned int divisor)
49 {
50 	struct mcp_sa11x0 *m = priv(mcp);
51 
52 	divisor /= 32;
53 
54 	m->mccr0 &= ~0x00007f00;
55 	m->mccr0 |= divisor << 8;
56 	writel_relaxed(m->mccr0, MCCR0(m));
57 }
58 
59 static void
60 mcp_sa11x0_set_audio_divisor(struct mcp *mcp, unsigned int divisor)
61 {
62 	struct mcp_sa11x0 *m = priv(mcp);
63 
64 	divisor /= 32;
65 
66 	m->mccr0 &= ~0x0000007f;
67 	m->mccr0 |= divisor;
68 	writel_relaxed(m->mccr0, MCCR0(m));
69 }
70 
71 /*
72  * Write data to the device.  The bit should be set after 3 subframe
73  * times (each frame is 64 clocks).  We wait a maximum of 6 subframes.
74  * We really should try doing something more productive while we
75  * wait.
76  */
77 static void
78 mcp_sa11x0_write(struct mcp *mcp, unsigned int reg, unsigned int val)
79 {
80 	struct mcp_sa11x0 *m = priv(mcp);
81 	int ret = -ETIME;
82 	int i;
83 
84 	writel_relaxed(reg << 17 | MCDR2_Wr | (val & 0xffff), MCDR2(m));
85 
86 	for (i = 0; i < 2; i++) {
87 		udelay(mcp->rw_timeout);
88 		if (readl_relaxed(MCSR(m)) & MCSR_CWC) {
89 			ret = 0;
90 			break;
91 		}
92 	}
93 
94 	if (ret < 0)
95 		printk(KERN_WARNING "mcp: write timed out\n");
96 }
97 
98 /*
99  * Read data from the device.  The bit should be set after 3 subframe
100  * times (each frame is 64 clocks).  We wait a maximum of 6 subframes.
101  * We really should try doing something more productive while we
102  * wait.
103  */
104 static unsigned int
105 mcp_sa11x0_read(struct mcp *mcp, unsigned int reg)
106 {
107 	struct mcp_sa11x0 *m = priv(mcp);
108 	int ret = -ETIME;
109 	int i;
110 
111 	writel_relaxed(reg << 17 | MCDR2_Rd, MCDR2(m));
112 
113 	for (i = 0; i < 2; i++) {
114 		udelay(mcp->rw_timeout);
115 		if (readl_relaxed(MCSR(m)) & MCSR_CRC) {
116 			ret = readl_relaxed(MCDR2(m)) & 0xffff;
117 			break;
118 		}
119 	}
120 
121 	if (ret < 0)
122 		printk(KERN_WARNING "mcp: read timed out\n");
123 
124 	return ret;
125 }
126 
127 static void mcp_sa11x0_enable(struct mcp *mcp)
128 {
129 	struct mcp_sa11x0 *m = priv(mcp);
130 
131 	writel(-1, MCSR(m));
132 	m->mccr0 |= MCCR0_MCE;
133 	writel_relaxed(m->mccr0, MCCR0(m));
134 }
135 
136 static void mcp_sa11x0_disable(struct mcp *mcp)
137 {
138 	struct mcp_sa11x0 *m = priv(mcp);
139 
140 	m->mccr0 &= ~MCCR0_MCE;
141 	writel_relaxed(m->mccr0, MCCR0(m));
142 }
143 
144 /*
145  * Our methods.
146  */
147 static struct mcp_ops mcp_sa11x0 = {
148 	.set_telecom_divisor	= mcp_sa11x0_set_telecom_divisor,
149 	.set_audio_divisor	= mcp_sa11x0_set_audio_divisor,
150 	.reg_write		= mcp_sa11x0_write,
151 	.reg_read		= mcp_sa11x0_read,
152 	.enable			= mcp_sa11x0_enable,
153 	.disable		= mcp_sa11x0_disable,
154 };
155 
156 static int mcp_sa11x0_probe(struct platform_device *dev)
157 {
158 	struct mcp_plat_data *data = dev_get_platdata(&dev->dev);
159 	struct resource *mem0, *mem1;
160 	struct mcp_sa11x0 *m;
161 	struct mcp *mcp;
162 	int ret;
163 
164 	if (!data)
165 		return -ENODEV;
166 
167 	mem0 = platform_get_resource(dev, IORESOURCE_MEM, 0);
168 	mem1 = platform_get_resource(dev, IORESOURCE_MEM, 1);
169 	if (!mem0 || !mem1)
170 		return -ENXIO;
171 
172 	if (!request_mem_region(mem0->start, resource_size(mem0),
173 				DRIVER_NAME)) {
174 		ret = -EBUSY;
175 		goto err_mem0;
176 	}
177 
178 	if (!request_mem_region(mem1->start, resource_size(mem1),
179 				DRIVER_NAME)) {
180 		ret = -EBUSY;
181 		goto err_mem1;
182 	}
183 
184 	mcp = mcp_host_alloc(&dev->dev, sizeof(struct mcp_sa11x0));
185 	if (!mcp) {
186 		ret = -ENOMEM;
187 		goto err_alloc;
188 	}
189 
190 	mcp->owner		= THIS_MODULE;
191 	mcp->ops		= &mcp_sa11x0;
192 	mcp->sclk_rate		= data->sclk_rate;
193 
194 	m = priv(mcp);
195 	m->mccr0 = data->mccr0 | 0x7f7f;
196 	m->mccr1 = data->mccr1;
197 
198 	m->base0 = ioremap(mem0->start, resource_size(mem0));
199 	m->base1 = ioremap(mem1->start, resource_size(mem1));
200 	if (!m->base0 || !m->base1) {
201 		ret = -ENOMEM;
202 		goto err_ioremap;
203 	}
204 
205 	platform_set_drvdata(dev, mcp);
206 
207 	/*
208 	 * Initialise device.  Note that we initially
209 	 * set the sampling rate to minimum.
210 	 */
211 	writel_relaxed(-1, MCSR(m));
212 	writel_relaxed(m->mccr1, MCCR1(m));
213 	writel_relaxed(m->mccr0, MCCR0(m));
214 
215 	/*
216 	 * Calculate the read/write timeout (us) from the bit clock
217 	 * rate.  This is the period for 3 64-bit frames.  Always
218 	 * round this time up.
219 	 */
220 	mcp->rw_timeout = (64 * 3 * 1000000 + mcp->sclk_rate - 1) /
221 			  mcp->sclk_rate;
222 
223 	ret = mcp_host_add(mcp, data->codec_pdata);
224 	if (ret == 0)
225 		return 0;
226 
227  err_ioremap:
228 	iounmap(m->base1);
229 	iounmap(m->base0);
230 	mcp_host_free(mcp);
231  err_alloc:
232 	release_mem_region(mem1->start, resource_size(mem1));
233  err_mem1:
234 	release_mem_region(mem0->start, resource_size(mem0));
235  err_mem0:
236 	return ret;
237 }
238 
239 static int mcp_sa11x0_remove(struct platform_device *dev)
240 {
241 	struct mcp *mcp = platform_get_drvdata(dev);
242 	struct mcp_sa11x0 *m = priv(mcp);
243 	struct resource *mem0, *mem1;
244 
245 	if (m->mccr0 & MCCR0_MCE)
246 		dev_warn(&dev->dev,
247 			 "device left active (missing disable call?)\n");
248 
249 	mem0 = platform_get_resource(dev, IORESOURCE_MEM, 0);
250 	mem1 = platform_get_resource(dev, IORESOURCE_MEM, 1);
251 
252 	mcp_host_del(mcp);
253 	iounmap(m->base1);
254 	iounmap(m->base0);
255 	mcp_host_free(mcp);
256 	release_mem_region(mem1->start, resource_size(mem1));
257 	release_mem_region(mem0->start, resource_size(mem0));
258 
259 	return 0;
260 }
261 
262 #ifdef CONFIG_PM_SLEEP
263 static int mcp_sa11x0_suspend(struct device *dev)
264 {
265 	struct mcp_sa11x0 *m = priv(dev_get_drvdata(dev));
266 
267 	if (m->mccr0 & MCCR0_MCE)
268 		dev_warn(dev, "device left active (missing disable call?)\n");
269 
270 	writel(m->mccr0 & ~MCCR0_MCE, MCCR0(m));
271 
272 	return 0;
273 }
274 
275 static int mcp_sa11x0_resume(struct device *dev)
276 {
277 	struct mcp_sa11x0 *m = priv(dev_get_drvdata(dev));
278 
279 	writel_relaxed(m->mccr1, MCCR1(m));
280 	writel_relaxed(m->mccr0, MCCR0(m));
281 
282 	return 0;
283 }
284 #endif
285 
286 static const struct dev_pm_ops mcp_sa11x0_pm_ops = {
287 #ifdef CONFIG_PM_SLEEP
288 	.suspend = mcp_sa11x0_suspend,
289 	.freeze = mcp_sa11x0_suspend,
290 	.poweroff = mcp_sa11x0_suspend,
291 	.resume_noirq = mcp_sa11x0_resume,
292 	.thaw_noirq = mcp_sa11x0_resume,
293 	.restore_noirq = mcp_sa11x0_resume,
294 #endif
295 };
296 
297 static struct platform_driver mcp_sa11x0_driver = {
298 	.probe		= mcp_sa11x0_probe,
299 	.remove		= mcp_sa11x0_remove,
300 	.driver		= {
301 		.name	= DRIVER_NAME,
302 		.owner	= THIS_MODULE,
303 		.pm	= &mcp_sa11x0_pm_ops,
304 	},
305 };
306 
307 /*
308  * This needs re-working
309  */
310 module_platform_driver(mcp_sa11x0_driver);
311 
312 MODULE_ALIAS("platform:" DRIVER_NAME);
313 MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
314 MODULE_DESCRIPTION("SA11x0 multimedia communications port driver");
315 MODULE_LICENSE("GPL");
316