xref: /linux/drivers/misc/ad525x_dpot.c (revision 6093a688a07da07808f0122f9aa2a3eed250d853)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * ad525x_dpot: Driver for the Analog Devices digital potentiometers
4  * Copyright (c) 2009-2010 Analog Devices, Inc.
5  * Author: Michael Hennerich <michael.hennerich@analog.com>
6  *
7  * DEVID		#Wipers		#Positions	Resistor Options (kOhm)
8  * AD5258		1		64		1, 10, 50, 100
9  * AD5259		1		256		5, 10, 50, 100
10  * AD5251		2		64		1, 10, 50, 100
11  * AD5252		2		256		1, 10, 50, 100
12  * AD5255		3		512		25, 250
13  * AD5253		4		64		1, 10, 50, 100
14  * AD5254		4		256		1, 10, 50, 100
15  * AD5160		1		256		5, 10, 50, 100
16  * AD5161		1		256		5, 10, 50, 100
17  * AD5162		2		256		2.5, 10, 50, 100
18  * AD5165		1		256		100
19  * AD5200		1		256		10, 50
20  * AD5201		1		33		10, 50
21  * AD5203		4		64		10, 100
22  * AD5204		4		256		10, 50, 100
23  * AD5206		6		256		10, 50, 100
24  * AD5207		2		256		10, 50, 100
25  * AD5231		1		1024		10, 50, 100
26  * AD5232		2		256		10, 50, 100
27  * AD5233		4		64		10, 50, 100
28  * AD5235		2		1024		25, 250
29  * AD5260		1		256		20, 50, 200
30  * AD5262		2		256		20, 50, 200
31  * AD5263		4		256		20, 50, 200
32  * AD5290		1		256		10, 50, 100
33  * AD5291		1		256		20, 50, 100  (20-TP)
34  * AD5292		1		1024		20, 50, 100  (20-TP)
35  * AD5293		1		1024		20, 50, 100
36  * AD7376		1		128		10, 50, 100, 1M
37  * AD8400		1		256		1, 10, 50, 100
38  * AD8402		2		256		1, 10, 50, 100
39  * AD8403		4		256		1, 10, 50, 100
40  * ADN2850		3		512		25, 250
41  * AD5241		1		256		10, 100, 1M
42  * AD5246		1		128		5, 10, 50, 100
43  * AD5247		1		128		5, 10, 50, 100
44  * AD5245		1		256		5, 10, 50, 100
45  * AD5243		2		256		2.5, 10, 50, 100
46  * AD5248		2		256		2.5, 10, 50, 100
47  * AD5242		2		256		20, 50, 200
48  * AD5280		1		256		20, 50, 200
49  * AD5282		2		256		20, 50, 200
50  * ADN2860		3		512		25, 250
51  * AD5273		1		64		1, 10, 50, 100 (OTP)
52  * AD5171		1		64		5, 10, 50, 100 (OTP)
53  * AD5170		1		256		2.5, 10, 50, 100 (OTP)
54  * AD5172		2		256		2.5, 10, 50, 100 (OTP)
55  * AD5173		2		256		2.5, 10, 50, 100 (OTP)
56  * AD5270		1		1024		20, 50, 100 (50-TP)
57  * AD5271		1		256		20, 50, 100 (50-TP)
58  * AD5272		1		1024		20, 50, 100 (50-TP)
59  * AD5274		1		256		20, 50, 100 (50-TP)
60  *
61  * See Documentation/misc-devices/ad525x_dpot.rst for more info.
62  *
63  * derived from ad5258.c
64  * Copyright (c) 2009 Cyber Switching, Inc.
65  * Author: Chris Verges <chrisv@cyberswitching.com>
66  *
67  * derived from ad5252.c
68  * Copyright (c) 2006-2011 Michael Hennerich <michael.hennerich@analog.com>
69  */
70 
71 #include <linux/module.h>
72 #include <linux/device.h>
73 #include <linux/kernel.h>
74 #include <linux/delay.h>
75 #include <linux/slab.h>
76 #include <linux/string_choices.h>
77 
78 #include "ad525x_dpot.h"
79 
80 /*
81  * Client data (each client gets its own)
82  */
83 
84 struct dpot_data {
85 	struct ad_dpot_bus_data	bdata;
86 	struct mutex update_lock;
87 	unsigned int rdac_mask;
88 	unsigned int max_pos;
89 	unsigned long devid;
90 	unsigned int uid;
91 	unsigned int feat;
92 	unsigned int wipers;
93 	u16 rdac_cache[MAX_RDACS];
94 	DECLARE_BITMAP(otp_en_mask, MAX_RDACS);
95 };
96 
97 static inline int dpot_read_d8(struct dpot_data *dpot)
98 {
99 	return dpot->bdata.bops->read_d8(dpot->bdata.client);
100 }
101 
102 static inline int dpot_read_r8d8(struct dpot_data *dpot, u8 reg)
103 {
104 	return dpot->bdata.bops->read_r8d8(dpot->bdata.client, reg);
105 }
106 
107 static inline int dpot_read_r8d16(struct dpot_data *dpot, u8 reg)
108 {
109 	return dpot->bdata.bops->read_r8d16(dpot->bdata.client, reg);
110 }
111 
112 static inline int dpot_write_d8(struct dpot_data *dpot, u8 val)
113 {
114 	return dpot->bdata.bops->write_d8(dpot->bdata.client, val);
115 }
116 
117 static inline int dpot_write_r8d8(struct dpot_data *dpot, u8 reg, u16 val)
118 {
119 	return dpot->bdata.bops->write_r8d8(dpot->bdata.client, reg, val);
120 }
121 
122 static inline int dpot_write_r8d16(struct dpot_data *dpot, u8 reg, u16 val)
123 {
124 	return dpot->bdata.bops->write_r8d16(dpot->bdata.client, reg, val);
125 }
126 
127 static s32 dpot_read_spi(struct dpot_data *dpot, u8 reg)
128 {
129 	unsigned int ctrl = 0;
130 	int value;
131 
132 	if (!(reg & (DPOT_ADDR_EEPROM | DPOT_ADDR_CMD))) {
133 
134 		if (dpot->feat & F_RDACS_WONLY)
135 			return dpot->rdac_cache[reg & DPOT_RDAC_MASK];
136 		if (dpot->uid == DPOT_UID(AD5291_ID) ||
137 			dpot->uid == DPOT_UID(AD5292_ID) ||
138 			dpot->uid == DPOT_UID(AD5293_ID)) {
139 
140 			value = dpot_read_r8d8(dpot,
141 				DPOT_AD5291_READ_RDAC << 2);
142 
143 			if (value < 0)
144 				return value;
145 
146 			if (dpot->uid == DPOT_UID(AD5291_ID))
147 				value = value >> 2;
148 
149 			return value;
150 		} else if (dpot->uid == DPOT_UID(AD5270_ID) ||
151 			dpot->uid == DPOT_UID(AD5271_ID)) {
152 
153 			value = dpot_read_r8d8(dpot,
154 				DPOT_AD5270_1_2_4_READ_RDAC << 2);
155 
156 			if (value < 0)
157 				return value;
158 
159 			if (dpot->uid == DPOT_UID(AD5271_ID))
160 				value = value >> 2;
161 
162 			return value;
163 		}
164 
165 		ctrl = DPOT_SPI_READ_RDAC;
166 	} else if (reg & DPOT_ADDR_EEPROM) {
167 		ctrl = DPOT_SPI_READ_EEPROM;
168 	}
169 
170 	if (dpot->feat & F_SPI_16BIT)
171 		return dpot_read_r8d8(dpot, ctrl);
172 	else if (dpot->feat & F_SPI_24BIT)
173 		return dpot_read_r8d16(dpot, ctrl);
174 
175 	return -EFAULT;
176 }
177 
178 static s32 dpot_read_i2c(struct dpot_data *dpot, u8 reg)
179 {
180 	int value;
181 	unsigned int ctrl = 0;
182 
183 	switch (dpot->uid) {
184 	case DPOT_UID(AD5246_ID):
185 	case DPOT_UID(AD5247_ID):
186 		return dpot_read_d8(dpot);
187 	case DPOT_UID(AD5245_ID):
188 	case DPOT_UID(AD5241_ID):
189 	case DPOT_UID(AD5242_ID):
190 	case DPOT_UID(AD5243_ID):
191 	case DPOT_UID(AD5248_ID):
192 	case DPOT_UID(AD5280_ID):
193 	case DPOT_UID(AD5282_ID):
194 		ctrl = ((reg & DPOT_RDAC_MASK) == DPOT_RDAC0) ?
195 			0 : DPOT_AD5282_RDAC_AB;
196 		return dpot_read_r8d8(dpot, ctrl);
197 	case DPOT_UID(AD5170_ID):
198 	case DPOT_UID(AD5171_ID):
199 	case DPOT_UID(AD5273_ID):
200 			return dpot_read_d8(dpot);
201 	case DPOT_UID(AD5172_ID):
202 	case DPOT_UID(AD5173_ID):
203 		ctrl = ((reg & DPOT_RDAC_MASK) == DPOT_RDAC0) ?
204 			0 : DPOT_AD5172_3_A0;
205 		return dpot_read_r8d8(dpot, ctrl);
206 	case DPOT_UID(AD5272_ID):
207 	case DPOT_UID(AD5274_ID):
208 		dpot_write_r8d8(dpot,
209 				(DPOT_AD5270_1_2_4_READ_RDAC << 2), 0);
210 
211 		value = dpot_read_r8d16(dpot, DPOT_AD5270_1_2_4_RDAC << 2);
212 		if (value < 0)
213 			return value;
214 		/*
215 		 * AD5272/AD5274 returns high byte first, however
216 		 * underling smbus expects low byte first.
217 		 */
218 		value = swab16(value);
219 
220 		if (dpot->uid == DPOT_UID(AD5274_ID))
221 			value = value >> 2;
222 		return value;
223 	default:
224 		if ((reg & DPOT_REG_TOL) || (dpot->max_pos > 256))
225 			return dpot_read_r8d16(dpot, (reg & 0xF8) |
226 					((reg & 0x7) << 1));
227 		else
228 			return dpot_read_r8d8(dpot, reg);
229 	}
230 }
231 
232 static s32 dpot_read(struct dpot_data *dpot, u8 reg)
233 {
234 	if (dpot->feat & F_SPI)
235 		return dpot_read_spi(dpot, reg);
236 	else
237 		return dpot_read_i2c(dpot, reg);
238 }
239 
240 static s32 dpot_write_spi(struct dpot_data *dpot, u8 reg, u16 value)
241 {
242 	unsigned int val = 0;
243 
244 	if (!(reg & (DPOT_ADDR_EEPROM | DPOT_ADDR_CMD | DPOT_ADDR_OTP))) {
245 		if (dpot->feat & F_RDACS_WONLY)
246 			dpot->rdac_cache[reg & DPOT_RDAC_MASK] = value;
247 
248 		if (dpot->feat & F_AD_APPDATA) {
249 			if (dpot->feat & F_SPI_8BIT) {
250 				val = ((reg & DPOT_RDAC_MASK) <<
251 					DPOT_MAX_POS(dpot->devid)) |
252 					value;
253 				return dpot_write_d8(dpot, val);
254 			} else if (dpot->feat & F_SPI_16BIT) {
255 				val = ((reg & DPOT_RDAC_MASK) <<
256 					DPOT_MAX_POS(dpot->devid)) |
257 					value;
258 				return dpot_write_r8d8(dpot, val >> 8,
259 					val & 0xFF);
260 			} else
261 				BUG();
262 		} else {
263 			if (dpot->uid == DPOT_UID(AD5291_ID) ||
264 				dpot->uid == DPOT_UID(AD5292_ID) ||
265 				dpot->uid == DPOT_UID(AD5293_ID)) {
266 
267 				dpot_write_r8d8(dpot, DPOT_AD5291_CTRLREG << 2,
268 						DPOT_AD5291_UNLOCK_CMD);
269 
270 				if (dpot->uid == DPOT_UID(AD5291_ID))
271 					value = value << 2;
272 
273 				return dpot_write_r8d8(dpot,
274 					(DPOT_AD5291_RDAC << 2) |
275 					(value >> 8), value & 0xFF);
276 			} else if (dpot->uid == DPOT_UID(AD5270_ID) ||
277 				dpot->uid == DPOT_UID(AD5271_ID)) {
278 				dpot_write_r8d8(dpot,
279 						DPOT_AD5270_1_2_4_CTRLREG << 2,
280 						DPOT_AD5270_1_2_4_UNLOCK_CMD);
281 
282 				if (dpot->uid == DPOT_UID(AD5271_ID))
283 					value = value << 2;
284 
285 				return dpot_write_r8d8(dpot,
286 					(DPOT_AD5270_1_2_4_RDAC << 2) |
287 					(value >> 8), value & 0xFF);
288 			}
289 			val = DPOT_SPI_RDAC | (reg & DPOT_RDAC_MASK);
290 		}
291 	} else if (reg & DPOT_ADDR_EEPROM) {
292 		val = DPOT_SPI_EEPROM | (reg & DPOT_RDAC_MASK);
293 	} else if (reg & DPOT_ADDR_CMD) {
294 		switch (reg) {
295 		case DPOT_DEC_ALL_6DB:
296 			val = DPOT_SPI_DEC_ALL_6DB;
297 			break;
298 		case DPOT_INC_ALL_6DB:
299 			val = DPOT_SPI_INC_ALL_6DB;
300 			break;
301 		case DPOT_DEC_ALL:
302 			val = DPOT_SPI_DEC_ALL;
303 			break;
304 		case DPOT_INC_ALL:
305 			val = DPOT_SPI_INC_ALL;
306 			break;
307 		}
308 	} else if (reg & DPOT_ADDR_OTP) {
309 		if (dpot->uid == DPOT_UID(AD5291_ID) ||
310 			dpot->uid == DPOT_UID(AD5292_ID)) {
311 			return dpot_write_r8d8(dpot,
312 				DPOT_AD5291_STORE_XTPM << 2, 0);
313 		} else if (dpot->uid == DPOT_UID(AD5270_ID) ||
314 			dpot->uid == DPOT_UID(AD5271_ID)) {
315 			return dpot_write_r8d8(dpot,
316 				DPOT_AD5270_1_2_4_STORE_XTPM << 2, 0);
317 		}
318 	} else
319 		BUG();
320 
321 	if (dpot->feat & F_SPI_16BIT)
322 		return dpot_write_r8d8(dpot, val, value);
323 	else if (dpot->feat & F_SPI_24BIT)
324 		return dpot_write_r8d16(dpot, val, value);
325 
326 	return -EFAULT;
327 }
328 
329 static s32 dpot_write_i2c(struct dpot_data *dpot, u8 reg, u16 value)
330 {
331 	/* Only write the instruction byte for certain commands */
332 	unsigned int tmp = 0, ctrl = 0;
333 
334 	switch (dpot->uid) {
335 	case DPOT_UID(AD5246_ID):
336 	case DPOT_UID(AD5247_ID):
337 		return dpot_write_d8(dpot, value);
338 
339 	case DPOT_UID(AD5245_ID):
340 	case DPOT_UID(AD5241_ID):
341 	case DPOT_UID(AD5242_ID):
342 	case DPOT_UID(AD5243_ID):
343 	case DPOT_UID(AD5248_ID):
344 	case DPOT_UID(AD5280_ID):
345 	case DPOT_UID(AD5282_ID):
346 		ctrl = ((reg & DPOT_RDAC_MASK) == DPOT_RDAC0) ?
347 			0 : DPOT_AD5282_RDAC_AB;
348 		return dpot_write_r8d8(dpot, ctrl, value);
349 	case DPOT_UID(AD5171_ID):
350 	case DPOT_UID(AD5273_ID):
351 		if (reg & DPOT_ADDR_OTP) {
352 			tmp = dpot_read_d8(dpot);
353 			if (tmp >> 6) /* Ready to Program? */
354 				return -EFAULT;
355 			ctrl = DPOT_AD5273_FUSE;
356 		}
357 		return dpot_write_r8d8(dpot, ctrl, value);
358 	case DPOT_UID(AD5172_ID):
359 	case DPOT_UID(AD5173_ID):
360 		ctrl = ((reg & DPOT_RDAC_MASK) == DPOT_RDAC0) ?
361 			0 : DPOT_AD5172_3_A0;
362 		if (reg & DPOT_ADDR_OTP) {
363 			tmp = dpot_read_r8d16(dpot, ctrl);
364 			if (tmp >> 14) /* Ready to Program? */
365 				return -EFAULT;
366 			ctrl |= DPOT_AD5170_2_3_FUSE;
367 		}
368 		return dpot_write_r8d8(dpot, ctrl, value);
369 	case DPOT_UID(AD5170_ID):
370 		if (reg & DPOT_ADDR_OTP) {
371 			tmp = dpot_read_r8d16(dpot, tmp);
372 			if (tmp >> 14) /* Ready to Program? */
373 				return -EFAULT;
374 			ctrl = DPOT_AD5170_2_3_FUSE;
375 		}
376 		return dpot_write_r8d8(dpot, ctrl, value);
377 	case DPOT_UID(AD5272_ID):
378 	case DPOT_UID(AD5274_ID):
379 		dpot_write_r8d8(dpot, DPOT_AD5270_1_2_4_CTRLREG << 2,
380 				DPOT_AD5270_1_2_4_UNLOCK_CMD);
381 
382 		if (reg & DPOT_ADDR_OTP)
383 			return dpot_write_r8d8(dpot,
384 					DPOT_AD5270_1_2_4_STORE_XTPM << 2, 0);
385 
386 		if (dpot->uid == DPOT_UID(AD5274_ID))
387 			value = value << 2;
388 
389 		return dpot_write_r8d8(dpot, (DPOT_AD5270_1_2_4_RDAC << 2) |
390 				       (value >> 8), value & 0xFF);
391 	default:
392 		if (reg & DPOT_ADDR_CMD)
393 			return dpot_write_d8(dpot, reg);
394 
395 		if (dpot->max_pos > 256)
396 			return dpot_write_r8d16(dpot, (reg & 0xF8) |
397 						((reg & 0x7) << 1), value);
398 		else
399 			/* All other registers require instruction + data bytes */
400 			return dpot_write_r8d8(dpot, reg, value);
401 	}
402 }
403 
404 static s32 dpot_write(struct dpot_data *dpot, u8 reg, u16 value)
405 {
406 	if (dpot->feat & F_SPI)
407 		return dpot_write_spi(dpot, reg, value);
408 	else
409 		return dpot_write_i2c(dpot, reg, value);
410 }
411 
412 /* sysfs functions */
413 
414 static ssize_t sysfs_show_reg(struct device *dev,
415 			      struct device_attribute *attr,
416 			      char *buf, u32 reg)
417 {
418 	struct dpot_data *data = dev_get_drvdata(dev);
419 	s32 value;
420 
421 	if (reg & DPOT_ADDR_OTP_EN)
422 		return sprintf(buf, "%s\n", str_enabled_disabled(
423 			test_bit(DPOT_RDAC_MASK & reg, data->otp_en_mask)));
424 
425 	mutex_lock(&data->update_lock);
426 	value = dpot_read(data, reg);
427 	mutex_unlock(&data->update_lock);
428 
429 	if (value < 0)
430 		return -EINVAL;
431 	/*
432 	 * Let someone else deal with converting this ...
433 	 * the tolerance is a two-byte value where the MSB
434 	 * is a sign + integer value, and the LSB is a
435 	 * decimal value.  See page 18 of the AD5258
436 	 * datasheet (Rev. A) for more details.
437 	 */
438 
439 	if (reg & DPOT_REG_TOL)
440 		return sprintf(buf, "0x%04x\n", value & 0xFFFF);
441 	else
442 		return sprintf(buf, "%u\n", value & data->rdac_mask);
443 }
444 
445 static ssize_t sysfs_set_reg(struct device *dev,
446 			     struct device_attribute *attr,
447 			     const char *buf, size_t count, u32 reg)
448 {
449 	struct dpot_data *data = dev_get_drvdata(dev);
450 	unsigned long value;
451 	int err;
452 
453 	if (reg & DPOT_ADDR_OTP_EN) {
454 		if (sysfs_streq(buf, "enabled"))
455 			set_bit(DPOT_RDAC_MASK & reg, data->otp_en_mask);
456 		else
457 			clear_bit(DPOT_RDAC_MASK & reg, data->otp_en_mask);
458 
459 		return count;
460 	}
461 
462 	if ((reg & DPOT_ADDR_OTP) &&
463 		!test_bit(DPOT_RDAC_MASK & reg, data->otp_en_mask))
464 		return -EPERM;
465 
466 	err = kstrtoul(buf, 10, &value);
467 	if (err)
468 		return err;
469 
470 	if (value > data->rdac_mask)
471 		value = data->rdac_mask;
472 
473 	mutex_lock(&data->update_lock);
474 	dpot_write(data, reg, value);
475 	if (reg & DPOT_ADDR_EEPROM)
476 		msleep(26);	/* Sleep while the EEPROM updates */
477 	else if (reg & DPOT_ADDR_OTP)
478 		msleep(400);	/* Sleep while the OTP updates */
479 	mutex_unlock(&data->update_lock);
480 
481 	return count;
482 }
483 
484 static ssize_t sysfs_do_cmd(struct device *dev,
485 			    struct device_attribute *attr,
486 			    const char *buf, size_t count, u32 reg)
487 {
488 	struct dpot_data *data = dev_get_drvdata(dev);
489 
490 	mutex_lock(&data->update_lock);
491 	dpot_write(data, reg, 0);
492 	mutex_unlock(&data->update_lock);
493 
494 	return count;
495 }
496 
497 /* ------------------------------------------------------------------------- */
498 
499 #define DPOT_DEVICE_SHOW(_name, _reg) static ssize_t \
500 show_##_name(struct device *dev, \
501 			  struct device_attribute *attr, char *buf) \
502 { \
503 	return sysfs_show_reg(dev, attr, buf, _reg); \
504 }
505 
506 #define DPOT_DEVICE_SET(_name, _reg) static ssize_t \
507 set_##_name(struct device *dev, \
508 			 struct device_attribute *attr, \
509 			 const char *buf, size_t count) \
510 { \
511 	return sysfs_set_reg(dev, attr, buf, count, _reg); \
512 }
513 
514 #define DPOT_DEVICE_SHOW_SET(name, reg) \
515 DPOT_DEVICE_SHOW(name, reg) \
516 DPOT_DEVICE_SET(name, reg) \
517 static DEVICE_ATTR(name, S_IWUSR | S_IRUGO, show_##name, set_##name)
518 
519 #define DPOT_DEVICE_SHOW_ONLY(name, reg) \
520 DPOT_DEVICE_SHOW(name, reg) \
521 static DEVICE_ATTR(name, S_IWUSR | S_IRUGO, show_##name, NULL)
522 
523 DPOT_DEVICE_SHOW_SET(rdac0, DPOT_ADDR_RDAC | DPOT_RDAC0);
524 DPOT_DEVICE_SHOW_SET(eeprom0, DPOT_ADDR_EEPROM | DPOT_RDAC0);
525 DPOT_DEVICE_SHOW_ONLY(tolerance0, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC0);
526 DPOT_DEVICE_SHOW_SET(otp0, DPOT_ADDR_OTP | DPOT_RDAC0);
527 DPOT_DEVICE_SHOW_SET(otp0en, DPOT_ADDR_OTP_EN | DPOT_RDAC0);
528 
529 DPOT_DEVICE_SHOW_SET(rdac1, DPOT_ADDR_RDAC | DPOT_RDAC1);
530 DPOT_DEVICE_SHOW_SET(eeprom1, DPOT_ADDR_EEPROM | DPOT_RDAC1);
531 DPOT_DEVICE_SHOW_ONLY(tolerance1, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC1);
532 DPOT_DEVICE_SHOW_SET(otp1, DPOT_ADDR_OTP | DPOT_RDAC1);
533 DPOT_DEVICE_SHOW_SET(otp1en, DPOT_ADDR_OTP_EN | DPOT_RDAC1);
534 
535 DPOT_DEVICE_SHOW_SET(rdac2, DPOT_ADDR_RDAC | DPOT_RDAC2);
536 DPOT_DEVICE_SHOW_SET(eeprom2, DPOT_ADDR_EEPROM | DPOT_RDAC2);
537 DPOT_DEVICE_SHOW_ONLY(tolerance2, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC2);
538 DPOT_DEVICE_SHOW_SET(otp2, DPOT_ADDR_OTP | DPOT_RDAC2);
539 DPOT_DEVICE_SHOW_SET(otp2en, DPOT_ADDR_OTP_EN | DPOT_RDAC2);
540 
541 DPOT_DEVICE_SHOW_SET(rdac3, DPOT_ADDR_RDAC | DPOT_RDAC3);
542 DPOT_DEVICE_SHOW_SET(eeprom3, DPOT_ADDR_EEPROM | DPOT_RDAC3);
543 DPOT_DEVICE_SHOW_ONLY(tolerance3, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC3);
544 DPOT_DEVICE_SHOW_SET(otp3, DPOT_ADDR_OTP | DPOT_RDAC3);
545 DPOT_DEVICE_SHOW_SET(otp3en, DPOT_ADDR_OTP_EN | DPOT_RDAC3);
546 
547 DPOT_DEVICE_SHOW_SET(rdac4, DPOT_ADDR_RDAC | DPOT_RDAC4);
548 DPOT_DEVICE_SHOW_SET(eeprom4, DPOT_ADDR_EEPROM | DPOT_RDAC4);
549 DPOT_DEVICE_SHOW_ONLY(tolerance4, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC4);
550 DPOT_DEVICE_SHOW_SET(otp4, DPOT_ADDR_OTP | DPOT_RDAC4);
551 DPOT_DEVICE_SHOW_SET(otp4en, DPOT_ADDR_OTP_EN | DPOT_RDAC4);
552 
553 DPOT_DEVICE_SHOW_SET(rdac5, DPOT_ADDR_RDAC | DPOT_RDAC5);
554 DPOT_DEVICE_SHOW_SET(eeprom5, DPOT_ADDR_EEPROM | DPOT_RDAC5);
555 DPOT_DEVICE_SHOW_ONLY(tolerance5, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC5);
556 DPOT_DEVICE_SHOW_SET(otp5, DPOT_ADDR_OTP | DPOT_RDAC5);
557 DPOT_DEVICE_SHOW_SET(otp5en, DPOT_ADDR_OTP_EN | DPOT_RDAC5);
558 
559 static const struct attribute *dpot_attrib_wipers[] = {
560 	&dev_attr_rdac0.attr,
561 	&dev_attr_rdac1.attr,
562 	&dev_attr_rdac2.attr,
563 	&dev_attr_rdac3.attr,
564 	&dev_attr_rdac4.attr,
565 	&dev_attr_rdac5.attr,
566 	NULL
567 };
568 
569 static const struct attribute *dpot_attrib_eeprom[] = {
570 	&dev_attr_eeprom0.attr,
571 	&dev_attr_eeprom1.attr,
572 	&dev_attr_eeprom2.attr,
573 	&dev_attr_eeprom3.attr,
574 	&dev_attr_eeprom4.attr,
575 	&dev_attr_eeprom5.attr,
576 	NULL
577 };
578 
579 static const struct attribute *dpot_attrib_otp[] = {
580 	&dev_attr_otp0.attr,
581 	&dev_attr_otp1.attr,
582 	&dev_attr_otp2.attr,
583 	&dev_attr_otp3.attr,
584 	&dev_attr_otp4.attr,
585 	&dev_attr_otp5.attr,
586 	NULL
587 };
588 
589 static const struct attribute *dpot_attrib_otp_en[] = {
590 	&dev_attr_otp0en.attr,
591 	&dev_attr_otp1en.attr,
592 	&dev_attr_otp2en.attr,
593 	&dev_attr_otp3en.attr,
594 	&dev_attr_otp4en.attr,
595 	&dev_attr_otp5en.attr,
596 	NULL
597 };
598 
599 static const struct attribute *dpot_attrib_tolerance[] = {
600 	&dev_attr_tolerance0.attr,
601 	&dev_attr_tolerance1.attr,
602 	&dev_attr_tolerance2.attr,
603 	&dev_attr_tolerance3.attr,
604 	&dev_attr_tolerance4.attr,
605 	&dev_attr_tolerance5.attr,
606 	NULL
607 };
608 
609 /* ------------------------------------------------------------------------- */
610 
611 #define DPOT_DEVICE_DO_CMD(_name, _cmd) static ssize_t \
612 set_##_name(struct device *dev, \
613 			 struct device_attribute *attr, \
614 			 const char *buf, size_t count) \
615 { \
616 	return sysfs_do_cmd(dev, attr, buf, count, _cmd); \
617 } \
618 static DEVICE_ATTR(_name, S_IWUSR | S_IRUGO, NULL, set_##_name)
619 
620 DPOT_DEVICE_DO_CMD(inc_all, DPOT_INC_ALL);
621 DPOT_DEVICE_DO_CMD(dec_all, DPOT_DEC_ALL);
622 DPOT_DEVICE_DO_CMD(inc_all_6db, DPOT_INC_ALL_6DB);
623 DPOT_DEVICE_DO_CMD(dec_all_6db, DPOT_DEC_ALL_6DB);
624 
625 static struct attribute *ad525x_attributes_commands[] = {
626 	&dev_attr_inc_all.attr,
627 	&dev_attr_dec_all.attr,
628 	&dev_attr_inc_all_6db.attr,
629 	&dev_attr_dec_all_6db.attr,
630 	NULL
631 };
632 
633 static const struct attribute_group ad525x_group_commands = {
634 	.attrs = ad525x_attributes_commands,
635 };
636 
637 static int ad_dpot_add_files(struct device *dev,
638 		unsigned int features, unsigned int rdac)
639 {
640 	int err = sysfs_create_file(&dev->kobj,
641 		dpot_attrib_wipers[rdac]);
642 	if (features & F_CMD_EEP)
643 		err |= sysfs_create_file(&dev->kobj,
644 			dpot_attrib_eeprom[rdac]);
645 	if (features & F_CMD_TOL)
646 		err |= sysfs_create_file(&dev->kobj,
647 			dpot_attrib_tolerance[rdac]);
648 	if (features & F_CMD_OTP) {
649 		err |= sysfs_create_file(&dev->kobj,
650 			dpot_attrib_otp_en[rdac]);
651 		err |= sysfs_create_file(&dev->kobj,
652 			dpot_attrib_otp[rdac]);
653 	}
654 
655 	if (err)
656 		dev_err(dev, "failed to register sysfs hooks for RDAC%d\n",
657 			rdac);
658 
659 	return err;
660 }
661 
662 static inline void ad_dpot_remove_files(struct device *dev,
663 		unsigned int features, unsigned int rdac)
664 {
665 	sysfs_remove_file(&dev->kobj,
666 		dpot_attrib_wipers[rdac]);
667 	if (features & F_CMD_EEP)
668 		sysfs_remove_file(&dev->kobj,
669 			dpot_attrib_eeprom[rdac]);
670 	if (features & F_CMD_TOL)
671 		sysfs_remove_file(&dev->kobj,
672 			dpot_attrib_tolerance[rdac]);
673 	if (features & F_CMD_OTP) {
674 		sysfs_remove_file(&dev->kobj,
675 			dpot_attrib_otp_en[rdac]);
676 		sysfs_remove_file(&dev->kobj,
677 			dpot_attrib_otp[rdac]);
678 	}
679 }
680 
681 int ad_dpot_probe(struct device *dev,
682 		struct ad_dpot_bus_data *bdata, unsigned long devid,
683 			    const char *name)
684 {
685 
686 	struct dpot_data *data;
687 	int i, err = 0;
688 
689 	data = kzalloc(sizeof(struct dpot_data), GFP_KERNEL);
690 	if (!data) {
691 		err = -ENOMEM;
692 		goto exit;
693 	}
694 
695 	dev_set_drvdata(dev, data);
696 	mutex_init(&data->update_lock);
697 
698 	data->bdata = *bdata;
699 	data->devid = devid;
700 
701 	data->max_pos = 1 << DPOT_MAX_POS(devid);
702 	data->rdac_mask = data->max_pos - 1;
703 	data->feat = DPOT_FEAT(devid);
704 	data->uid = DPOT_UID(devid);
705 	data->wipers = DPOT_WIPERS(devid);
706 
707 	for (i = DPOT_RDAC0; i < MAX_RDACS; i++)
708 		if (data->wipers & (1 << i)) {
709 			err = ad_dpot_add_files(dev, data->feat, i);
710 			if (err)
711 				goto exit_remove_files;
712 			/* power-up midscale */
713 			if (data->feat & F_RDACS_WONLY)
714 				data->rdac_cache[i] = data->max_pos / 2;
715 		}
716 
717 	if (data->feat & F_CMD_INC)
718 		err = sysfs_create_group(&dev->kobj, &ad525x_group_commands);
719 
720 	if (err) {
721 		dev_err(dev, "failed to register sysfs hooks\n");
722 		goto exit_free;
723 	}
724 
725 	dev_info(dev, "%s %d-Position Digital Potentiometer registered\n",
726 		 name, data->max_pos);
727 
728 	return 0;
729 
730 exit_remove_files:
731 	for (i = DPOT_RDAC0; i < MAX_RDACS; i++)
732 		if (data->wipers & (1 << i))
733 			ad_dpot_remove_files(dev, data->feat, i);
734 
735 exit_free:
736 	kfree(data);
737 	dev_set_drvdata(dev, NULL);
738 exit:
739 	dev_err(dev, "failed to create client for %s ID 0x%lX\n",
740 		name, devid);
741 	return err;
742 }
743 EXPORT_SYMBOL(ad_dpot_probe);
744 
745 void ad_dpot_remove(struct device *dev)
746 {
747 	struct dpot_data *data = dev_get_drvdata(dev);
748 	int i;
749 
750 	for (i = DPOT_RDAC0; i < MAX_RDACS; i++)
751 		if (data->wipers & (1 << i))
752 			ad_dpot_remove_files(dev, data->feat, i);
753 
754 	kfree(data);
755 }
756 EXPORT_SYMBOL(ad_dpot_remove);
757 
758 
759 MODULE_AUTHOR("Chris Verges <chrisv@cyberswitching.com>, "
760 	      "Michael Hennerich <michael.hennerich@analog.com>");
761 MODULE_DESCRIPTION("Digital potentiometer driver");
762 MODULE_LICENSE("GPL");
763