xref: /linux/drivers/mfd/wm8400-core.c (revision 6ee738610f41b59733f63718f0bdbcba7d3a3f12)
1 /*
2  * Core driver for WM8400.
3  *
4  * Copyright 2008 Wolfson Microelectronics PLC.
5  *
6  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 of the
11  * License, or (at your option) any later version.
12  *
13  */
14 
15 #include <linux/bug.h>
16 #include <linux/i2c.h>
17 #include <linux/kernel.h>
18 #include <linux/mfd/core.h>
19 #include <linux/mfd/wm8400-private.h>
20 #include <linux/mfd/wm8400-audio.h>
21 
22 static struct {
23 	u16  readable;    /* Mask of readable bits */
24 	u16  writable;    /* Mask of writable bits */
25 	u16  vol;         /* Mask of volatile bits */
26 	int  is_codec;    /* Register controlled by codec reset */
27 	u16  default_val; /* Value on reset */
28 } reg_data[] = {
29 	{ 0xFFFF, 0xFFFF, 0x0000, 0, 0x6172 }, /* R0 */
30 	{ 0x7000, 0x0000, 0x8000, 0, 0x0000 }, /* R1 */
31 	{ 0xFF17, 0xFF17, 0x0000, 0, 0x0000 }, /* R2 */
32 	{ 0xEBF3, 0xEBF3, 0x0000, 1, 0x6000 }, /* R3 */
33 	{ 0x3CF3, 0x3CF3, 0x0000, 1, 0x0000 }, /* R4  */
34 	{ 0xF1F8, 0xF1F8, 0x0000, 1, 0x4050 }, /* R5  */
35 	{ 0xFC1F, 0xFC1F, 0x0000, 1, 0x4000 }, /* R6  */
36 	{ 0xDFDE, 0xDFDE, 0x0000, 1, 0x01C8 }, /* R7  */
37 	{ 0xFCFC, 0xFCFC, 0x0000, 1, 0x0000 }, /* R8  */
38 	{ 0xEFFF, 0xEFFF, 0x0000, 1, 0x0040 }, /* R9  */
39 	{ 0xEFFF, 0xEFFF, 0x0000, 1, 0x0040 }, /* R10 */
40 	{ 0x27F7, 0x27F7, 0x0000, 1, 0x0004 }, /* R11 */
41 	{ 0x01FF, 0x01FF, 0x0000, 1, 0x00C0 }, /* R12 */
42 	{ 0x01FF, 0x01FF, 0x0000, 1, 0x00C0 }, /* R13 */
43 	{ 0x1FEF, 0x1FEF, 0x0000, 1, 0x0000 }, /* R14 */
44 	{ 0x0163, 0x0163, 0x0000, 1, 0x0100 }, /* R15 */
45 	{ 0x01FF, 0x01FF, 0x0000, 1, 0x00C0 }, /* R16 */
46 	{ 0x01FF, 0x01FF, 0x0000, 1, 0x00C0 }, /* R17 */
47 	{ 0x1FFF, 0x0FFF, 0x0000, 1, 0x0000 }, /* R18 */
48 	{ 0xFFFF, 0xFFFF, 0x0000, 1, 0x1000 }, /* R19 */
49 	{ 0xFFFF, 0xFFFF, 0x0000, 1, 0x1010 }, /* R20 */
50 	{ 0xFFFF, 0xFFFF, 0x0000, 1, 0x1010 }, /* R21 */
51 	{ 0x0FDD, 0x0FDD, 0x0000, 1, 0x8000 }, /* R22 */
52 	{ 0x1FFF, 0x1FFF, 0x0000, 1, 0x0800 }, /* R23 */
53 	{ 0x0000, 0x01DF, 0x0000, 1, 0x008B }, /* R24 */
54 	{ 0x0000, 0x01DF, 0x0000, 1, 0x008B }, /* R25 */
55 	{ 0x0000, 0x01DF, 0x0000, 1, 0x008B }, /* R26 */
56 	{ 0x0000, 0x01DF, 0x0000, 1, 0x008B }, /* R27 */
57 	{ 0x0000, 0x01FF, 0x0000, 1, 0x0000 }, /* R28 */
58 	{ 0x0000, 0x01FF, 0x0000, 1, 0x0000 }, /* R29 */
59 	{ 0x0000, 0x0077, 0x0000, 1, 0x0066 }, /* R30 */
60 	{ 0x0000, 0x0033, 0x0000, 1, 0x0022 }, /* R31 */
61 	{ 0x0000, 0x01FF, 0x0000, 1, 0x0079 }, /* R32 */
62 	{ 0x0000, 0x01FF, 0x0000, 1, 0x0079 }, /* R33 */
63 	{ 0x0000, 0x0003, 0x0000, 1, 0x0003 }, /* R34 */
64 	{ 0x0000, 0x01FF, 0x0000, 1, 0x0003 }, /* R35 */
65 	{ 0x0000, 0x0000, 0x0000, 0, 0x0000 }, /* R36 */
66 	{ 0x0000, 0x003F, 0x0000, 1, 0x0100 }, /* R37 */
67 	{ 0x0000, 0x0000, 0x0000, 0, 0x0000 }, /* R38 */
68 	{ 0x0000, 0x000F, 0x0000, 0, 0x0000 }, /* R39 */
69 	{ 0x0000, 0x00FF, 0x0000, 1, 0x0000 }, /* R40 */
70 	{ 0x0000, 0x01B7, 0x0000, 1, 0x0000 }, /* R41 */
71 	{ 0x0000, 0x01B7, 0x0000, 1, 0x0000 }, /* R42 */
72 	{ 0x0000, 0x01FF, 0x0000, 1, 0x0000 }, /* R43 */
73 	{ 0x0000, 0x01FF, 0x0000, 1, 0x0000 }, /* R44 */
74 	{ 0x0000, 0x00FD, 0x0000, 1, 0x0000 }, /* R45 */
75 	{ 0x0000, 0x00FD, 0x0000, 1, 0x0000 }, /* R46 */
76 	{ 0x0000, 0x01FF, 0x0000, 1, 0x0000 }, /* R47 */
77 	{ 0x0000, 0x01FF, 0x0000, 1, 0x0000 }, /* R48 */
78 	{ 0x0000, 0x01FF, 0x0000, 1, 0x0000 }, /* R49 */
79 	{ 0x0000, 0x01FF, 0x0000, 1, 0x0000 }, /* R50 */
80 	{ 0x0000, 0x01B3, 0x0000, 1, 0x0180 }, /* R51 */
81 	{ 0x0000, 0x0077, 0x0000, 1, 0x0000 }, /* R52 */
82 	{ 0x0000, 0x0077, 0x0000, 1, 0x0000 }, /* R53 */
83 	{ 0x0000, 0x00FF, 0x0000, 1, 0x0000 }, /* R54 */
84 	{ 0x0000, 0x0001, 0x0000, 1, 0x0000 }, /* R55 */
85 	{ 0x0000, 0x003F, 0x0000, 1, 0x0000 }, /* R56 */
86 	{ 0x0000, 0x004F, 0x0000, 1, 0x0000 }, /* R57 */
87 	{ 0x0000, 0x00FD, 0x0000, 1, 0x0000 }, /* R58 */
88 	{ 0x0000, 0x0000, 0x0000, 0, 0x0000 }, /* R59 */
89 	{ 0x1FFF, 0x1FFF, 0x0000, 1, 0x0000 }, /* R60 */
90 	{ 0xFFFF, 0xFFFF, 0x0000, 1, 0x0000 }, /* R61 */
91 	{ 0x03FF, 0x03FF, 0x0000, 1, 0x0000 }, /* R62 */
92 	{ 0x007F, 0x007F, 0x0000, 1, 0x0000 }, /* R63 */
93 	{ 0x0000, 0x0000, 0x0000, 0, 0x0000 }, /* R64 */
94 	{ 0xDFFF, 0xDFFF, 0x0000, 0, 0x0000 }, /* R65 */
95 	{ 0xDFFF, 0xDFFF, 0x0000, 0, 0x0000 }, /* R66 */
96 	{ 0xDFFF, 0xDFFF, 0x0000, 0, 0x0000 }, /* R67 */
97 	{ 0xDFFF, 0xDFFF, 0x0000, 0, 0x0000 }, /* R68 */
98 	{ 0x0000, 0x0000, 0x0000, 0, 0x0000 }, /* R69 */
99 	{ 0xFFFF, 0xFFFF, 0x0000, 0, 0x4400 }, /* R70 */
100 	{ 0x23FF, 0x23FF, 0x0000, 0, 0x0000 }, /* R71 */
101 	{ 0xFFFF, 0xFFFF, 0x0000, 0, 0x4400 }, /* R72 */
102 	{ 0x23FF, 0x23FF, 0x0000, 0, 0x0000 }, /* R73 */
103 	{ 0x0000, 0x0000, 0x0000, 0, 0x0000 }, /* R74 */
104 	{ 0x000E, 0x000E, 0x0000, 0, 0x0008 }, /* R75 */
105 	{ 0xE00F, 0xE00F, 0x0000, 0, 0x0000 }, /* R76 */
106 	{ 0x0000, 0x0000, 0x0000, 0, 0x0000 }, /* R77 */
107 	{ 0x03C0, 0x03C0, 0x0000, 0, 0x02C0 }, /* R78 */
108 	{ 0xFFFF, 0x0000, 0xffff, 0, 0x0000 }, /* R79 */
109 	{ 0xFFFF, 0xFFFF, 0x0000, 0, 0x0000 }, /* R80 */
110 	{ 0xFFFF, 0x0000, 0xffff, 0, 0x0000 }, /* R81 */
111 	{ 0x2BFF, 0x0000, 0xffff, 0, 0x0000 }, /* R82 */
112 	{ 0x0000, 0x0000, 0x0000, 0, 0x0000 }, /* R83 */
113 	{ 0x80FF, 0x80FF, 0x0000, 0, 0x00ff }, /* R84 */
114 };
115 
116 static int wm8400_read(struct wm8400 *wm8400, u8 reg, int num_regs, u16 *dest)
117 {
118 	int i, ret = 0;
119 
120 	BUG_ON(reg + num_regs - 1 > ARRAY_SIZE(wm8400->reg_cache));
121 
122 	/* If there are any volatile reads then read back the entire block */
123 	for (i = reg; i < reg + num_regs; i++)
124 		if (reg_data[i].vol) {
125 			ret = wm8400->read_dev(wm8400->io_data, reg,
126 					       num_regs, dest);
127 			if (ret != 0)
128 				return ret;
129 			for (i = 0; i < num_regs; i++)
130 				dest[i] = be16_to_cpu(dest[i]);
131 
132 			return 0;
133 		}
134 
135 	/* Otherwise use the cache */
136 	memcpy(dest, &wm8400->reg_cache[reg], num_regs * sizeof(u16));
137 
138 	return 0;
139 }
140 
141 static int wm8400_write(struct wm8400 *wm8400, u8 reg, int num_regs,
142 			u16 *src)
143 {
144 	int ret, i;
145 
146 	BUG_ON(reg + num_regs - 1 > ARRAY_SIZE(wm8400->reg_cache));
147 
148 	for (i = 0; i < num_regs; i++) {
149 		BUG_ON(!reg_data[reg + i].writable);
150 		wm8400->reg_cache[reg + i] = src[i];
151 		src[i] = cpu_to_be16(src[i]);
152 	}
153 
154 	/* Do the actual I/O */
155 	ret = wm8400->write_dev(wm8400->io_data, reg, num_regs, src);
156 	if (ret != 0)
157 		return -EIO;
158 
159 	return 0;
160 }
161 
162 /**
163  * wm8400_reg_read - Single register read
164  *
165  * @wm8400: Pointer to wm8400 control structure
166  * @reg:    Register to read
167  *
168  * @return  Read value
169  */
170 u16 wm8400_reg_read(struct wm8400 *wm8400, u8 reg)
171 {
172 	u16 val;
173 
174 	mutex_lock(&wm8400->io_lock);
175 
176 	wm8400_read(wm8400, reg, 1, &val);
177 
178 	mutex_unlock(&wm8400->io_lock);
179 
180 	return val;
181 }
182 EXPORT_SYMBOL_GPL(wm8400_reg_read);
183 
184 int wm8400_block_read(struct wm8400 *wm8400, u8 reg, int count, u16 *data)
185 {
186 	int ret;
187 
188 	mutex_lock(&wm8400->io_lock);
189 
190 	ret = wm8400_read(wm8400, reg, count, data);
191 
192 	mutex_unlock(&wm8400->io_lock);
193 
194 	return ret;
195 }
196 EXPORT_SYMBOL_GPL(wm8400_block_read);
197 
198 /**
199  * wm8400_set_bits - Bitmask write
200  *
201  * @wm8400: Pointer to wm8400 control structure
202  * @reg:    Register to access
203  * @mask:   Mask of bits to change
204  * @val:    Value to set for masked bits
205  */
206 int wm8400_set_bits(struct wm8400 *wm8400, u8 reg, u16 mask, u16 val)
207 {
208 	u16 tmp;
209 	int ret;
210 
211 	mutex_lock(&wm8400->io_lock);
212 
213 	ret = wm8400_read(wm8400, reg, 1, &tmp);
214 	tmp = (tmp & ~mask) | val;
215 	if (ret == 0)
216 		ret = wm8400_write(wm8400, reg, 1, &tmp);
217 
218 	mutex_unlock(&wm8400->io_lock);
219 
220 	return ret;
221 }
222 EXPORT_SYMBOL_GPL(wm8400_set_bits);
223 
224 /**
225  * wm8400_reset_codec_reg_cache - Reset cached codec registers to
226  * their default values.
227  */
228 void wm8400_reset_codec_reg_cache(struct wm8400 *wm8400)
229 {
230 	int i;
231 
232 	mutex_lock(&wm8400->io_lock);
233 
234 	/* Reset all codec registers to their initial value */
235 	for (i = 0; i < ARRAY_SIZE(wm8400->reg_cache); i++)
236 		if (reg_data[i].is_codec)
237 			wm8400->reg_cache[i] = reg_data[i].default_val;
238 
239 	mutex_unlock(&wm8400->io_lock);
240 }
241 EXPORT_SYMBOL_GPL(wm8400_reset_codec_reg_cache);
242 
243 static int wm8400_register_codec(struct wm8400 *wm8400)
244 {
245 	struct mfd_cell cell = {
246 		.name = "wm8400-codec",
247 		.driver_data = wm8400,
248 	};
249 
250 	return mfd_add_devices(wm8400->dev, -1, &cell, 1, NULL, 0);
251 }
252 
253 /*
254  * wm8400_init - Generic initialisation
255  *
256  * The WM8400 can be configured as either an I2C or SPI device.  Probe
257  * functions for each bus set up the accessors then call into this to
258  * set up the device itself.
259  */
260 static int wm8400_init(struct wm8400 *wm8400,
261 		       struct wm8400_platform_data *pdata)
262 {
263 	u16 reg;
264 	int ret, i;
265 
266 	mutex_init(&wm8400->io_lock);
267 
268 	dev_set_drvdata(wm8400->dev, wm8400);
269 
270 	/* Check that this is actually a WM8400 */
271 	ret = wm8400->read_dev(wm8400->io_data, WM8400_RESET_ID, 1, &reg);
272 	if (ret != 0) {
273 		dev_err(wm8400->dev, "Chip ID register read failed\n");
274 		return -EIO;
275 	}
276 	if (be16_to_cpu(reg) != reg_data[WM8400_RESET_ID].default_val) {
277 		dev_err(wm8400->dev, "Device is not a WM8400, ID is %x\n",
278 			be16_to_cpu(reg));
279 		return -ENODEV;
280 	}
281 
282 	/* We don't know what state the hardware is in and since this
283 	 * is a PMIC we can't reset it safely so initialise the register
284 	 * cache from the hardware.
285 	 */
286 	ret = wm8400->read_dev(wm8400->io_data, 0,
287 			       ARRAY_SIZE(wm8400->reg_cache),
288 			       wm8400->reg_cache);
289 	if (ret != 0) {
290 		dev_err(wm8400->dev, "Register cache read failed\n");
291 		return -EIO;
292 	}
293 	for (i = 0; i < ARRAY_SIZE(wm8400->reg_cache); i++)
294 		wm8400->reg_cache[i] = be16_to_cpu(wm8400->reg_cache[i]);
295 
296 	/* If the codec is in reset use hard coded values */
297 	if (!(wm8400->reg_cache[WM8400_POWER_MANAGEMENT_1] & WM8400_CODEC_ENA))
298 		for (i = 0; i < ARRAY_SIZE(wm8400->reg_cache); i++)
299 			if (reg_data[i].is_codec)
300 				wm8400->reg_cache[i] = reg_data[i].default_val;
301 
302 	ret = wm8400_read(wm8400, WM8400_ID, 1, &reg);
303 	if (ret != 0) {
304 		dev_err(wm8400->dev, "ID register read failed: %d\n", ret);
305 		return ret;
306 	}
307 	reg = (reg & WM8400_CHIP_REV_MASK) >> WM8400_CHIP_REV_SHIFT;
308 	dev_info(wm8400->dev, "WM8400 revision %x\n", reg);
309 
310 	ret = wm8400_register_codec(wm8400);
311 	if (ret != 0) {
312 		dev_err(wm8400->dev, "Failed to register codec\n");
313 		goto err_children;
314 	}
315 
316 	if (pdata && pdata->platform_init) {
317 		ret = pdata->platform_init(wm8400->dev);
318 		if (ret != 0) {
319 			dev_err(wm8400->dev, "Platform init failed: %d\n",
320 				ret);
321 			goto err_children;
322 		}
323 	} else
324 		dev_warn(wm8400->dev, "No platform initialisation supplied\n");
325 
326 	return 0;
327 
328 err_children:
329 	mfd_remove_devices(wm8400->dev);
330 	return ret;
331 }
332 
333 static void wm8400_release(struct wm8400 *wm8400)
334 {
335 	mfd_remove_devices(wm8400->dev);
336 }
337 
338 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
339 static int wm8400_i2c_read(void *io_data, char reg, int count, u16 *dest)
340 {
341 	struct i2c_client *i2c = io_data;
342 	struct i2c_msg xfer[2];
343 	int ret;
344 
345 	/* Write register */
346 	xfer[0].addr = i2c->addr;
347 	xfer[0].flags = 0;
348 	xfer[0].len = 1;
349 	xfer[0].buf = &reg;
350 
351 	/* Read data */
352 	xfer[1].addr = i2c->addr;
353 	xfer[1].flags = I2C_M_RD;
354 	xfer[1].len = count * sizeof(u16);
355 	xfer[1].buf = (u8 *)dest;
356 
357 	ret = i2c_transfer(i2c->adapter, xfer, 2);
358 	if (ret == 2)
359 		ret = 0;
360 	else if (ret >= 0)
361 		ret = -EIO;
362 
363 	return ret;
364 }
365 
366 static int wm8400_i2c_write(void *io_data, char reg, int count, const u16 *src)
367 {
368 	struct i2c_client *i2c = io_data;
369 	u8 *msg;
370 	int ret;
371 
372 	/* We add 1 byte for device register - ideally I2C would gather. */
373 	msg = kmalloc((count * sizeof(u16)) + 1, GFP_KERNEL);
374 	if (msg == NULL)
375 		return -ENOMEM;
376 
377 	msg[0] = reg;
378 	memcpy(&msg[1], src, count * sizeof(u16));
379 
380 	ret = i2c_master_send(i2c, msg, (count * sizeof(u16)) + 1);
381 
382 	if (ret == (count * 2) + 1)
383 		ret = 0;
384 	else if (ret >= 0)
385 		ret = -EIO;
386 
387 	kfree(msg);
388 
389 	return ret;
390 }
391 
392 static int wm8400_i2c_probe(struct i2c_client *i2c,
393 			    const struct i2c_device_id *id)
394 {
395 	struct wm8400 *wm8400;
396 	int ret;
397 
398 	wm8400 = kzalloc(sizeof(struct wm8400), GFP_KERNEL);
399 	if (wm8400 == NULL) {
400 		ret = -ENOMEM;
401 		goto err;
402 	}
403 
404 	wm8400->io_data = i2c;
405 	wm8400->read_dev = wm8400_i2c_read;
406 	wm8400->write_dev = wm8400_i2c_write;
407 	wm8400->dev = &i2c->dev;
408 	i2c_set_clientdata(i2c, wm8400);
409 
410 	ret = wm8400_init(wm8400, i2c->dev.platform_data);
411 	if (ret != 0)
412 		goto struct_err;
413 
414 	return 0;
415 
416 struct_err:
417 	i2c_set_clientdata(i2c, NULL);
418 	kfree(wm8400);
419 err:
420 	return ret;
421 }
422 
423 static int wm8400_i2c_remove(struct i2c_client *i2c)
424 {
425 	struct wm8400 *wm8400 = i2c_get_clientdata(i2c);
426 
427 	wm8400_release(wm8400);
428 	i2c_set_clientdata(i2c, NULL);
429 	kfree(wm8400);
430 
431 	return 0;
432 }
433 
434 static const struct i2c_device_id wm8400_i2c_id[] = {
435        { "wm8400", 0 },
436        { }
437 };
438 MODULE_DEVICE_TABLE(i2c, wm8400_i2c_id);
439 
440 static struct i2c_driver wm8400_i2c_driver = {
441 	.driver = {
442 		.name = "WM8400",
443 		.owner = THIS_MODULE,
444 	},
445 	.probe    = wm8400_i2c_probe,
446 	.remove   = wm8400_i2c_remove,
447 	.id_table = wm8400_i2c_id,
448 };
449 #endif
450 
451 static int __init wm8400_module_init(void)
452 {
453 	int ret = -ENODEV;
454 
455 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
456 	ret = i2c_add_driver(&wm8400_i2c_driver);
457 	if (ret != 0)
458 		pr_err("Failed to register I2C driver: %d\n", ret);
459 #endif
460 
461 	return ret;
462 }
463 subsys_initcall(wm8400_module_init);
464 
465 static void __exit wm8400_module_exit(void)
466 {
467 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
468 	i2c_del_driver(&wm8400_i2c_driver);
469 #endif
470 }
471 module_exit(wm8400_module_exit);
472 
473 MODULE_LICENSE("GPL");
474 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
475