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