Linux Audio

Check our new training course

Loading...
v3.1
  1/*
  2 * ad525x_dpot: Driver for the Analog Devices digital potentiometers
  3 * Copyright (c) 2009-2010 Analog Devices, Inc.
  4 * Author: Michael Hennerich <hennerich@blackfin.uclinux.org>
  5 *
  6 * DEVID		#Wipers		#Positions 	Resistor Options (kOhm)
  7 * AD5258		1		64		1, 10, 50, 100
  8 * AD5259		1		256		5, 10, 50, 100
  9 * AD5251		2		64		1, 10, 50, 100
 10 * AD5252		2		256		1, 10, 50, 100
 11 * AD5255		3		512		25, 250
 12 * AD5253		4		64		1, 10, 50, 100
 13 * AD5254		4		256		1, 10, 50, 100
 14 * AD5160		1		256		5, 10, 50, 100
 15 * AD5161		1		256		5, 10, 50, 100
 16 * AD5162		2		256		2.5, 10, 50, 100
 17 * AD5165		1		256		100
 18 * AD5200		1		256		10, 50
 19 * AD5201		1		33		10, 50
 20 * AD5203		4		64		10, 100
 21 * AD5204		4		256		10, 50, 100
 22 * AD5206		6		256		10, 50, 100
 23 * AD5207		2		256		10, 50, 100
 24 * AD5231		1		1024		10, 50, 100
 25 * AD5232		2		256		10, 50, 100
 26 * AD5233		4		64		10, 50, 100
 27 * AD5235		2		1024		25, 250
 28 * AD5260		1		256		20, 50, 200
 29 * AD5262		2		256		20, 50, 200
 30 * AD5263		4		256		20, 50, 200
 31 * AD5290		1		256		10, 50, 100
 32 * AD5291		1		256		20, 50, 100  (20-TP)
 33 * AD5292		1		1024		20, 50, 100  (20-TP)
 34 * AD5293		1		1024		20, 50, 100
 35 * AD7376		1		128		10, 50, 100, 1M
 36 * AD8400		1		256		1, 10, 50, 100
 37 * AD8402		2		256		1, 10, 50, 100
 38 * AD8403		4		256		1, 10, 50, 100
 39 * ADN2850		3		512		25, 250
 40 * AD5241		1		256		10, 100, 1M
 41 * AD5246		1		128		5, 10, 50, 100
 42 * AD5247		1		128		5, 10, 50, 100
 43 * AD5245		1		256		5, 10, 50, 100
 44 * AD5243		2		256		2.5, 10, 50, 100
 45 * AD5248		2		256		2.5, 10, 50, 100
 46 * AD5242		2		256		20, 50, 200
 47 * AD5280		1		256		20, 50, 200
 48 * AD5282		2		256		20, 50, 200
 49 * ADN2860		3		512		25, 250
 50 * AD5273		1		64		1, 10, 50, 100 (OTP)
 51 * AD5171		1		64		5, 10, 50, 100 (OTP)
 52 * AD5170		1		256		2.5, 10, 50, 100 (OTP)
 53 * AD5172		2		256		2.5, 10, 50, 100 (OTP)
 54 * AD5173		2		256		2.5, 10, 50, 100 (OTP)
 55 * AD5270		1		1024		20, 50, 100 (50-TP)
 56 * AD5271		1		256		20, 50, 100 (50-TP)
 57 * AD5272		1		1024		20, 50, 100 (50-TP)
 58 * AD5274		1		256		20, 50, 100 (50-TP)
 59 *
 60 * See Documentation/misc-devices/ad525x_dpot.txt for more info.
 61 *
 62 * derived from ad5258.c
 63 * Copyright (c) 2009 Cyber Switching, Inc.
 64 * Author: Chris Verges <chrisv@cyberswitching.com>
 65 *
 66 * derived from ad5252.c
 67 * Copyright (c) 2006 Michael Hennerich <hennerich@blackfin.uclinux.org>
 68 *
 69 * Licensed under the GPL-2 or later.
 70 */
 71
 72#include <linux/module.h>
 73#include <linux/device.h>
 74#include <linux/kernel.h>
 75#include <linux/init.h>
 76#include <linux/delay.h>
 77#include <linux/slab.h>
 78
 79#define DRIVER_VERSION			"0.2"
 80
 81#include "ad525x_dpot.h"
 82
 83/*
 84 * Client data (each client gets its own)
 85 */
 86
 87struct dpot_data {
 88	struct ad_dpot_bus_data	bdata;
 89	struct mutex update_lock;
 90	unsigned rdac_mask;
 91	unsigned max_pos;
 92	unsigned long devid;
 93	unsigned uid;
 94	unsigned feat;
 95	unsigned wipers;
 96	u16 rdac_cache[MAX_RDACS];
 97	DECLARE_BITMAP(otp_en_mask, MAX_RDACS);
 98};
 99
100static inline int dpot_read_d8(struct dpot_data *dpot)
101{
102	return dpot->bdata.bops->read_d8(dpot->bdata.client);
103}
104
105static inline int dpot_read_r8d8(struct dpot_data *dpot, u8 reg)
106{
107	return dpot->bdata.bops->read_r8d8(dpot->bdata.client, reg);
108}
109
110static inline int dpot_read_r8d16(struct dpot_data *dpot, u8 reg)
111{
112	return dpot->bdata.bops->read_r8d16(dpot->bdata.client, reg);
113}
114
115static inline int dpot_write_d8(struct dpot_data *dpot, u8 val)
116{
117	return dpot->bdata.bops->write_d8(dpot->bdata.client, val);
118}
119
120static inline int dpot_write_r8d8(struct dpot_data *dpot, u8 reg, u16 val)
121{
122	return dpot->bdata.bops->write_r8d8(dpot->bdata.client, reg, val);
123}
124
125static inline int dpot_write_r8d16(struct dpot_data *dpot, u8 reg, u16 val)
126{
127	return dpot->bdata.bops->write_r8d16(dpot->bdata.client, reg, val);
128}
129
130static s32 dpot_read_spi(struct dpot_data *dpot, u8 reg)
131{
132	unsigned ctrl = 0;
133	int value;
134
135	if (!(reg & (DPOT_ADDR_EEPROM | DPOT_ADDR_CMD))) {
136
137		if (dpot->feat & F_RDACS_WONLY)
138			return dpot->rdac_cache[reg & DPOT_RDAC_MASK];
139		if (dpot->uid == DPOT_UID(AD5291_ID) ||
140			dpot->uid == DPOT_UID(AD5292_ID) ||
141			dpot->uid == DPOT_UID(AD5293_ID)) {
142
143			value = dpot_read_r8d8(dpot,
144				DPOT_AD5291_READ_RDAC << 2);
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
178static s32 dpot_read_i2c(struct dpot_data *dpot, u8 reg)
179{
180	int value;
181	unsigned ctrl = 0;
182	switch (dpot->uid) {
183	case DPOT_UID(AD5246_ID):
184	case DPOT_UID(AD5247_ID):
185		return dpot_read_d8(dpot);
186	case DPOT_UID(AD5245_ID):
187	case DPOT_UID(AD5241_ID):
188	case DPOT_UID(AD5242_ID):
189	case DPOT_UID(AD5243_ID):
190	case DPOT_UID(AD5248_ID):
191	case DPOT_UID(AD5280_ID):
192	case DPOT_UID(AD5282_ID):
193		ctrl = ((reg & DPOT_RDAC_MASK) == DPOT_RDAC0) ?
194			0 : DPOT_AD5282_RDAC_AB;
195		return dpot_read_r8d8(dpot, ctrl);
196	case DPOT_UID(AD5170_ID):
197	case DPOT_UID(AD5171_ID):
198	case DPOT_UID(AD5273_ID):
199			return dpot_read_d8(dpot);
200	case DPOT_UID(AD5172_ID):
201	case DPOT_UID(AD5173_ID):
202		ctrl = ((reg & DPOT_RDAC_MASK) == DPOT_RDAC0) ?
203			0 : DPOT_AD5172_3_A0;
204		return dpot_read_r8d8(dpot, ctrl);
205	case DPOT_UID(AD5272_ID):
206	case DPOT_UID(AD5274_ID):
207			dpot_write_r8d8(dpot,
208				(DPOT_AD5270_1_2_4_READ_RDAC << 2), 0);
209
210			value = dpot_read_r8d16(dpot,
211				DPOT_AD5270_1_2_4_RDAC << 2);
212
213			if (value < 0)
214				return value;
215			/*
216			 * AD5272/AD5274 returns high byte first, however
217			 * underling smbus expects low byte first.
218			 */
219			value = swab16(value);
220
221			if (dpot->uid == DPOT_UID(AD5271_ID))
222				value = value >> 2;
223		return value;
224	default:
225		if ((reg & DPOT_REG_TOL) || (dpot->max_pos > 256))
226			return dpot_read_r8d16(dpot, (reg & 0xF8) |
227					((reg & 0x7) << 1));
228		else
229			return dpot_read_r8d8(dpot, reg);
230	}
231}
232
233static s32 dpot_read(struct dpot_data *dpot, u8 reg)
234{
235	if (dpot->feat & F_SPI)
236		return dpot_read_spi(dpot, reg);
237	else
238		return dpot_read_i2c(dpot, reg);
239}
240
241static s32 dpot_write_spi(struct dpot_data *dpot, u8 reg, u16 value)
242{
243	unsigned val = 0;
244
245	if (!(reg & (DPOT_ADDR_EEPROM | DPOT_ADDR_CMD | DPOT_ADDR_OTP))) {
246		if (dpot->feat & F_RDACS_WONLY)
247			dpot->rdac_cache[reg & DPOT_RDAC_MASK] = value;
248
249		if (dpot->feat & F_AD_APPDATA) {
250			if (dpot->feat & F_SPI_8BIT) {
251				val = ((reg & DPOT_RDAC_MASK) <<
252					DPOT_MAX_POS(dpot->devid)) |
253					value;
254				return dpot_write_d8(dpot, val);
255			} else if (dpot->feat & F_SPI_16BIT) {
256				val = ((reg & DPOT_RDAC_MASK) <<
257					DPOT_MAX_POS(dpot->devid)) |
258					value;
259				return dpot_write_r8d8(dpot, val >> 8,
260					val & 0xFF);
261			} else
262				BUG();
263		} else {
264			if (dpot->uid == DPOT_UID(AD5291_ID) ||
265				dpot->uid == DPOT_UID(AD5292_ID) ||
266				dpot->uid == DPOT_UID(AD5293_ID)) {
267
268				dpot_write_r8d8(dpot, DPOT_AD5291_CTRLREG << 2,
269						DPOT_AD5291_UNLOCK_CMD);
270
271				if (dpot->uid == DPOT_UID(AD5291_ID))
272					value = value << 2;
273
274				return dpot_write_r8d8(dpot,
275					(DPOT_AD5291_RDAC << 2) |
276					(value >> 8), value & 0xFF);
277			} else if (dpot->uid == DPOT_UID(AD5270_ID) ||
278				dpot->uid == DPOT_UID(AD5271_ID)) {
279				dpot_write_r8d8(dpot,
280						DPOT_AD5270_1_2_4_CTRLREG << 2,
281						DPOT_AD5270_1_2_4_UNLOCK_CMD);
282
283				if (dpot->uid == DPOT_UID(AD5271_ID))
284					value = value << 2;
285
286				return dpot_write_r8d8(dpot,
287					(DPOT_AD5270_1_2_4_RDAC << 2) |
288					(value >> 8), value & 0xFF);
289			}
290			val = DPOT_SPI_RDAC | (reg & DPOT_RDAC_MASK);
291		}
292	} else if (reg & DPOT_ADDR_EEPROM) {
293		val = DPOT_SPI_EEPROM | (reg & DPOT_RDAC_MASK);
294	} else if (reg & DPOT_ADDR_CMD) {
295		switch (reg) {
296		case DPOT_DEC_ALL_6DB:
297			val = DPOT_SPI_DEC_ALL_6DB;
298			break;
299		case DPOT_INC_ALL_6DB:
300			val = DPOT_SPI_INC_ALL_6DB;
301			break;
302		case DPOT_DEC_ALL:
303			val = DPOT_SPI_DEC_ALL;
304			break;
305		case DPOT_INC_ALL:
306			val = DPOT_SPI_INC_ALL;
307			break;
308		}
309	} else if (reg & DPOT_ADDR_OTP) {
310		if (dpot->uid == DPOT_UID(AD5291_ID) ||
311			dpot->uid == DPOT_UID(AD5292_ID)) {
312			return dpot_write_r8d8(dpot,
313				DPOT_AD5291_STORE_XTPM << 2, 0);
314		} else if (dpot->uid == DPOT_UID(AD5270_ID) ||
315			dpot->uid == DPOT_UID(AD5271_ID)) {
316			return dpot_write_r8d8(dpot,
317				DPOT_AD5270_1_2_4_STORE_XTPM << 2, 0);
318		}
319	} else
320		BUG();
321
322	if (dpot->feat & F_SPI_16BIT)
323		return dpot_write_r8d8(dpot, val, value);
324	else if (dpot->feat & F_SPI_24BIT)
325		return dpot_write_r8d16(dpot, val, value);
326
327	return -EFAULT;
328}
329
330static s32 dpot_write_i2c(struct dpot_data *dpot, u8 reg, u16 value)
331{
332	/* Only write the instruction byte for certain commands */
333	unsigned tmp = 0, ctrl = 0;
334
335	switch (dpot->uid) {
336	case DPOT_UID(AD5246_ID):
337	case DPOT_UID(AD5247_ID):
338		return dpot_write_d8(dpot, value);
339		break;
340
341	case DPOT_UID(AD5245_ID):
342	case DPOT_UID(AD5241_ID):
343	case DPOT_UID(AD5242_ID):
344	case DPOT_UID(AD5243_ID):
345	case DPOT_UID(AD5248_ID):
346	case DPOT_UID(AD5280_ID):
347	case DPOT_UID(AD5282_ID):
348		ctrl = ((reg & DPOT_RDAC_MASK) == DPOT_RDAC0) ?
349			0 : DPOT_AD5282_RDAC_AB;
350		return dpot_write_r8d8(dpot, ctrl, value);
351		break;
352	case DPOT_UID(AD5171_ID):
353	case DPOT_UID(AD5273_ID):
354		if (reg & DPOT_ADDR_OTP) {
355			tmp = dpot_read_d8(dpot);
356			if (tmp >> 6) /* Ready to Program? */
357				return -EFAULT;
358			ctrl = DPOT_AD5273_FUSE;
359		}
360		return dpot_write_r8d8(dpot, ctrl, value);
361		break;
362	case DPOT_UID(AD5172_ID):
363	case DPOT_UID(AD5173_ID):
364		ctrl = ((reg & DPOT_RDAC_MASK) == DPOT_RDAC0) ?
365			0 : DPOT_AD5172_3_A0;
366		if (reg & DPOT_ADDR_OTP) {
367			tmp = dpot_read_r8d16(dpot, ctrl);
368			if (tmp >> 14) /* Ready to Program? */
369				return -EFAULT;
370			ctrl |= DPOT_AD5170_2_3_FUSE;
371		}
372		return dpot_write_r8d8(dpot, ctrl, value);
373		break;
374	case DPOT_UID(AD5170_ID):
375		if (reg & DPOT_ADDR_OTP) {
376			tmp = dpot_read_r8d16(dpot, tmp);
377			if (tmp >> 14) /* Ready to Program? */
378				return -EFAULT;
379			ctrl = DPOT_AD5170_2_3_FUSE;
380		}
381		return dpot_write_r8d8(dpot, ctrl, value);
382		break;
383	case DPOT_UID(AD5272_ID):
384	case DPOT_UID(AD5274_ID):
385		dpot_write_r8d8(dpot, DPOT_AD5270_1_2_4_CTRLREG << 2,
386				DPOT_AD5270_1_2_4_UNLOCK_CMD);
387
388		if (reg & DPOT_ADDR_OTP)
389			return dpot_write_r8d8(dpot,
390					DPOT_AD5270_1_2_4_STORE_XTPM << 2, 0);
391
392		if (dpot->uid == DPOT_UID(AD5274_ID))
393			value = value << 2;
394
395		return dpot_write_r8d8(dpot, (DPOT_AD5270_1_2_4_RDAC << 2) |
396				       (value >> 8), value & 0xFF);
397		break;
398	default:
399		if (reg & DPOT_ADDR_CMD)
400			return dpot_write_d8(dpot, reg);
401
402		if (dpot->max_pos > 256)
403			return dpot_write_r8d16(dpot, (reg & 0xF8) |
404						((reg & 0x7) << 1), value);
405		else
406			/* All other registers require instruction + data bytes */
407			return dpot_write_r8d8(dpot, reg, value);
408	}
409}
410
411static s32 dpot_write(struct dpot_data *dpot, u8 reg, u16 value)
412{
413	if (dpot->feat & F_SPI)
414		return dpot_write_spi(dpot, reg, value);
415	else
416		return dpot_write_i2c(dpot, reg, value);
417}
418
419/* sysfs functions */
420
421static ssize_t sysfs_show_reg(struct device *dev,
422			      struct device_attribute *attr,
423			      char *buf, u32 reg)
424{
425	struct dpot_data *data = dev_get_drvdata(dev);
426	s32 value;
427
428	if (reg & DPOT_ADDR_OTP_EN)
429		return sprintf(buf, "%s\n",
430			test_bit(DPOT_RDAC_MASK & reg, data->otp_en_mask) ?
431			"enabled" : "disabled");
432
433
434	mutex_lock(&data->update_lock);
435	value = dpot_read(data, reg);
436	mutex_unlock(&data->update_lock);
437
438	if (value < 0)
439		return -EINVAL;
440	/*
441	 * Let someone else deal with converting this ...
442	 * the tolerance is a two-byte value where the MSB
443	 * is a sign + integer value, and the LSB is a
444	 * decimal value.  See page 18 of the AD5258
445	 * datasheet (Rev. A) for more details.
446	 */
447
448	if (reg & DPOT_REG_TOL)
449		return sprintf(buf, "0x%04x\n", value & 0xFFFF);
450	else
451		return sprintf(buf, "%u\n", value & data->rdac_mask);
452}
453
454static ssize_t sysfs_set_reg(struct device *dev,
455			     struct device_attribute *attr,
456			     const char *buf, size_t count, u32 reg)
457{
458	struct dpot_data *data = dev_get_drvdata(dev);
459	unsigned long value;
460	int err;
461
462	if (reg & DPOT_ADDR_OTP_EN) {
463		if (!strncmp(buf, "enabled", sizeof("enabled")))
464			set_bit(DPOT_RDAC_MASK & reg, data->otp_en_mask);
465		else
466			clear_bit(DPOT_RDAC_MASK & reg, data->otp_en_mask);
467
468		return count;
469	}
470
471	if ((reg & DPOT_ADDR_OTP) &&
472		!test_bit(DPOT_RDAC_MASK & reg, data->otp_en_mask))
473		return -EPERM;
474
475	err = strict_strtoul(buf, 10, &value);
476	if (err)
477		return err;
478
479	if (value > data->rdac_mask)
480		value = data->rdac_mask;
481
482	mutex_lock(&data->update_lock);
483	dpot_write(data, reg, value);
484	if (reg & DPOT_ADDR_EEPROM)
485		msleep(26);	/* Sleep while the EEPROM updates */
486	else if (reg & DPOT_ADDR_OTP)
487		msleep(400);	/* Sleep while the OTP updates */
488	mutex_unlock(&data->update_lock);
489
490	return count;
491}
492
493static ssize_t sysfs_do_cmd(struct device *dev,
494			    struct device_attribute *attr,
495			    const char *buf, size_t count, u32 reg)
496{
497	struct dpot_data *data = dev_get_drvdata(dev);
498
499	mutex_lock(&data->update_lock);
500	dpot_write(data, reg, 0);
501	mutex_unlock(&data->update_lock);
502
503	return count;
504}
505
506/* ------------------------------------------------------------------------- */
507
508#define DPOT_DEVICE_SHOW(_name, _reg) static ssize_t \
509show_##_name(struct device *dev, \
510			  struct device_attribute *attr, char *buf) \
511{ \
512	return sysfs_show_reg(dev, attr, buf, _reg); \
513}
514
515#define DPOT_DEVICE_SET(_name, _reg) static ssize_t \
516set_##_name(struct device *dev, \
517			 struct device_attribute *attr, \
518			 const char *buf, size_t count) \
519{ \
520	return sysfs_set_reg(dev, attr, buf, count, _reg); \
521}
522
523#define DPOT_DEVICE_SHOW_SET(name, reg) \
524DPOT_DEVICE_SHOW(name, reg) \
525DPOT_DEVICE_SET(name, reg) \
526static DEVICE_ATTR(name, S_IWUSR | S_IRUGO, show_##name, set_##name);
527
528#define DPOT_DEVICE_SHOW_ONLY(name, reg) \
529DPOT_DEVICE_SHOW(name, reg) \
530static DEVICE_ATTR(name, S_IWUSR | S_IRUGO, show_##name, NULL);
531
532DPOT_DEVICE_SHOW_SET(rdac0, DPOT_ADDR_RDAC | DPOT_RDAC0);
533DPOT_DEVICE_SHOW_SET(eeprom0, DPOT_ADDR_EEPROM | DPOT_RDAC0);
534DPOT_DEVICE_SHOW_ONLY(tolerance0, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC0);
535DPOT_DEVICE_SHOW_SET(otp0, DPOT_ADDR_OTP | DPOT_RDAC0);
536DPOT_DEVICE_SHOW_SET(otp0en, DPOT_ADDR_OTP_EN | DPOT_RDAC0);
537
538DPOT_DEVICE_SHOW_SET(rdac1, DPOT_ADDR_RDAC | DPOT_RDAC1);
539DPOT_DEVICE_SHOW_SET(eeprom1, DPOT_ADDR_EEPROM | DPOT_RDAC1);
540DPOT_DEVICE_SHOW_ONLY(tolerance1, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC1);
541DPOT_DEVICE_SHOW_SET(otp1, DPOT_ADDR_OTP | DPOT_RDAC1);
542DPOT_DEVICE_SHOW_SET(otp1en, DPOT_ADDR_OTP_EN | DPOT_RDAC1);
543
544DPOT_DEVICE_SHOW_SET(rdac2, DPOT_ADDR_RDAC | DPOT_RDAC2);
545DPOT_DEVICE_SHOW_SET(eeprom2, DPOT_ADDR_EEPROM | DPOT_RDAC2);
546DPOT_DEVICE_SHOW_ONLY(tolerance2, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC2);
547DPOT_DEVICE_SHOW_SET(otp2, DPOT_ADDR_OTP | DPOT_RDAC2);
548DPOT_DEVICE_SHOW_SET(otp2en, DPOT_ADDR_OTP_EN | DPOT_RDAC2);
549
550DPOT_DEVICE_SHOW_SET(rdac3, DPOT_ADDR_RDAC | DPOT_RDAC3);
551DPOT_DEVICE_SHOW_SET(eeprom3, DPOT_ADDR_EEPROM | DPOT_RDAC3);
552DPOT_DEVICE_SHOW_ONLY(tolerance3, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC3);
553DPOT_DEVICE_SHOW_SET(otp3, DPOT_ADDR_OTP | DPOT_RDAC3);
554DPOT_DEVICE_SHOW_SET(otp3en, DPOT_ADDR_OTP_EN | DPOT_RDAC3);
555
556DPOT_DEVICE_SHOW_SET(rdac4, DPOT_ADDR_RDAC | DPOT_RDAC4);
557DPOT_DEVICE_SHOW_SET(eeprom4, DPOT_ADDR_EEPROM | DPOT_RDAC4);
558DPOT_DEVICE_SHOW_ONLY(tolerance4, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC4);
559DPOT_DEVICE_SHOW_SET(otp4, DPOT_ADDR_OTP | DPOT_RDAC4);
560DPOT_DEVICE_SHOW_SET(otp4en, DPOT_ADDR_OTP_EN | DPOT_RDAC4);
561
562DPOT_DEVICE_SHOW_SET(rdac5, DPOT_ADDR_RDAC | DPOT_RDAC5);
563DPOT_DEVICE_SHOW_SET(eeprom5, DPOT_ADDR_EEPROM | DPOT_RDAC5);
564DPOT_DEVICE_SHOW_ONLY(tolerance5, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC5);
565DPOT_DEVICE_SHOW_SET(otp5, DPOT_ADDR_OTP | DPOT_RDAC5);
566DPOT_DEVICE_SHOW_SET(otp5en, DPOT_ADDR_OTP_EN | DPOT_RDAC5);
567
568static const struct attribute *dpot_attrib_wipers[] = {
569	&dev_attr_rdac0.attr,
570	&dev_attr_rdac1.attr,
571	&dev_attr_rdac2.attr,
572	&dev_attr_rdac3.attr,
573	&dev_attr_rdac4.attr,
574	&dev_attr_rdac5.attr,
575	NULL
576};
577
578static const struct attribute *dpot_attrib_eeprom[] = {
579	&dev_attr_eeprom0.attr,
580	&dev_attr_eeprom1.attr,
581	&dev_attr_eeprom2.attr,
582	&dev_attr_eeprom3.attr,
583	&dev_attr_eeprom4.attr,
584	&dev_attr_eeprom5.attr,
585	NULL
586};
587
588static const struct attribute *dpot_attrib_otp[] = {
589	&dev_attr_otp0.attr,
590	&dev_attr_otp1.attr,
591	&dev_attr_otp2.attr,
592	&dev_attr_otp3.attr,
593	&dev_attr_otp4.attr,
594	&dev_attr_otp5.attr,
595	NULL
596};
597
598static const struct attribute *dpot_attrib_otp_en[] = {
599	&dev_attr_otp0en.attr,
600	&dev_attr_otp1en.attr,
601	&dev_attr_otp2en.attr,
602	&dev_attr_otp3en.attr,
603	&dev_attr_otp4en.attr,
604	&dev_attr_otp5en.attr,
605	NULL
606};
607
608static const struct attribute *dpot_attrib_tolerance[] = {
609	&dev_attr_tolerance0.attr,
610	&dev_attr_tolerance1.attr,
611	&dev_attr_tolerance2.attr,
612	&dev_attr_tolerance3.attr,
613	&dev_attr_tolerance4.attr,
614	&dev_attr_tolerance5.attr,
615	NULL
616};
617
618/* ------------------------------------------------------------------------- */
619
620#define DPOT_DEVICE_DO_CMD(_name, _cmd) static ssize_t \
621set_##_name(struct device *dev, \
622			 struct device_attribute *attr, \
623			 const char *buf, size_t count) \
624{ \
625	return sysfs_do_cmd(dev, attr, buf, count, _cmd); \
626} \
627static DEVICE_ATTR(_name, S_IWUSR | S_IRUGO, NULL, set_##_name);
628
629DPOT_DEVICE_DO_CMD(inc_all, DPOT_INC_ALL);
630DPOT_DEVICE_DO_CMD(dec_all, DPOT_DEC_ALL);
631DPOT_DEVICE_DO_CMD(inc_all_6db, DPOT_INC_ALL_6DB);
632DPOT_DEVICE_DO_CMD(dec_all_6db, DPOT_DEC_ALL_6DB);
633
634static struct attribute *ad525x_attributes_commands[] = {
635	&dev_attr_inc_all.attr,
636	&dev_attr_dec_all.attr,
637	&dev_attr_inc_all_6db.attr,
638	&dev_attr_dec_all_6db.attr,
639	NULL
640};
641
642static const struct attribute_group ad525x_group_commands = {
643	.attrs = ad525x_attributes_commands,
644};
645
646__devinit int ad_dpot_add_files(struct device *dev,
647		unsigned features, unsigned rdac)
648{
649	int err = sysfs_create_file(&dev->kobj,
650		dpot_attrib_wipers[rdac]);
651	if (features & F_CMD_EEP)
652		err |= sysfs_create_file(&dev->kobj,
653			dpot_attrib_eeprom[rdac]);
654	if (features & F_CMD_TOL)
655		err |= sysfs_create_file(&dev->kobj,
656			dpot_attrib_tolerance[rdac]);
657	if (features & F_CMD_OTP) {
658		err |= sysfs_create_file(&dev->kobj,
659			dpot_attrib_otp_en[rdac]);
660		err |= sysfs_create_file(&dev->kobj,
661			dpot_attrib_otp[rdac]);
662	}
663
664	if (err)
665		dev_err(dev, "failed to register sysfs hooks for RDAC%d\n",
666			rdac);
667
668	return err;
669}
670
671inline void ad_dpot_remove_files(struct device *dev,
672		unsigned features, unsigned rdac)
673{
674	sysfs_remove_file(&dev->kobj,
675		dpot_attrib_wipers[rdac]);
676	if (features & F_CMD_EEP)
677		sysfs_remove_file(&dev->kobj,
678			dpot_attrib_eeprom[rdac]);
679	if (features & F_CMD_TOL)
680		sysfs_remove_file(&dev->kobj,
681			dpot_attrib_tolerance[rdac]);
682	if (features & F_CMD_OTP) {
683		sysfs_remove_file(&dev->kobj,
684			dpot_attrib_otp_en[rdac]);
685		sysfs_remove_file(&dev->kobj,
686			dpot_attrib_otp[rdac]);
687	}
688}
689
690__devinit int ad_dpot_probe(struct device *dev,
691		struct ad_dpot_bus_data *bdata, const struct ad_dpot_id *id)
 
692{
693
694	struct dpot_data *data;
695	int i, err = 0;
696
697	data = kzalloc(sizeof(struct dpot_data), GFP_KERNEL);
698	if (!data) {
699		err = -ENOMEM;
700		goto exit;
701	}
702
703	dev_set_drvdata(dev, data);
704	mutex_init(&data->update_lock);
705
706	data->bdata = *bdata;
707	data->devid = id->devid;
708
709	data->max_pos = 1 << DPOT_MAX_POS(data->devid);
710	data->rdac_mask = data->max_pos - 1;
711	data->feat = DPOT_FEAT(data->devid);
712	data->uid = DPOT_UID(data->devid);
713	data->wipers = DPOT_WIPERS(data->devid);
714
715	for (i = DPOT_RDAC0; i < MAX_RDACS; i++)
716		if (data->wipers & (1 << i)) {
717			err = ad_dpot_add_files(dev, data->feat, i);
718			if (err)
719				goto exit_remove_files;
720			/* power-up midscale */
721			if (data->feat & F_RDACS_WONLY)
722				data->rdac_cache[i] = data->max_pos / 2;
723		}
724
725	if (data->feat & F_CMD_INC)
726		err = sysfs_create_group(&dev->kobj, &ad525x_group_commands);
727
728	if (err) {
729		dev_err(dev, "failed to register sysfs hooks\n");
730		goto exit_free;
731	}
732
733	dev_info(dev, "%s %d-Position Digital Potentiometer registered\n",
734		 id->name, data->max_pos);
735
736	return 0;
737
738exit_remove_files:
739	for (i = DPOT_RDAC0; i < MAX_RDACS; i++)
740		if (data->wipers & (1 << i))
741			ad_dpot_remove_files(dev, data->feat, i);
742
743exit_free:
744	kfree(data);
745	dev_set_drvdata(dev, NULL);
746exit:
747	dev_err(dev, "failed to create client for %s ID 0x%lX\n",
748			id->name, id->devid);
749	return err;
750}
751EXPORT_SYMBOL(ad_dpot_probe);
752
753__devexit int ad_dpot_remove(struct device *dev)
754{
755	struct dpot_data *data = dev_get_drvdata(dev);
756	int i;
757
758	for (i = DPOT_RDAC0; i < MAX_RDACS; i++)
759		if (data->wipers & (1 << i))
760			ad_dpot_remove_files(dev, data->feat, i);
761
762	kfree(data);
763
764	return 0;
765}
766EXPORT_SYMBOL(ad_dpot_remove);
767
768
769MODULE_AUTHOR("Chris Verges <chrisv@cyberswitching.com>, "
770	      "Michael Hennerich <hennerich@blackfin.uclinux.org>");
771MODULE_DESCRIPTION("Digital potentiometer driver");
772MODULE_LICENSE("GPL");
773MODULE_VERSION(DRIVER_VERSION);
v3.15
  1/*
  2 * ad525x_dpot: Driver for the Analog Devices digital potentiometers
  3 * Copyright (c) 2009-2010 Analog Devices, Inc.
  4 * Author: Michael Hennerich <hennerich@blackfin.uclinux.org>
  5 *
  6 * DEVID		#Wipers		#Positions 	Resistor Options (kOhm)
  7 * AD5258		1		64		1, 10, 50, 100
  8 * AD5259		1		256		5, 10, 50, 100
  9 * AD5251		2		64		1, 10, 50, 100
 10 * AD5252		2		256		1, 10, 50, 100
 11 * AD5255		3		512		25, 250
 12 * AD5253		4		64		1, 10, 50, 100
 13 * AD5254		4		256		1, 10, 50, 100
 14 * AD5160		1		256		5, 10, 50, 100
 15 * AD5161		1		256		5, 10, 50, 100
 16 * AD5162		2		256		2.5, 10, 50, 100
 17 * AD5165		1		256		100
 18 * AD5200		1		256		10, 50
 19 * AD5201		1		33		10, 50
 20 * AD5203		4		64		10, 100
 21 * AD5204		4		256		10, 50, 100
 22 * AD5206		6		256		10, 50, 100
 23 * AD5207		2		256		10, 50, 100
 24 * AD5231		1		1024		10, 50, 100
 25 * AD5232		2		256		10, 50, 100
 26 * AD5233		4		64		10, 50, 100
 27 * AD5235		2		1024		25, 250
 28 * AD5260		1		256		20, 50, 200
 29 * AD5262		2		256		20, 50, 200
 30 * AD5263		4		256		20, 50, 200
 31 * AD5290		1		256		10, 50, 100
 32 * AD5291		1		256		20, 50, 100  (20-TP)
 33 * AD5292		1		1024		20, 50, 100  (20-TP)
 34 * AD5293		1		1024		20, 50, 100
 35 * AD7376		1		128		10, 50, 100, 1M
 36 * AD8400		1		256		1, 10, 50, 100
 37 * AD8402		2		256		1, 10, 50, 100
 38 * AD8403		4		256		1, 10, 50, 100
 39 * ADN2850		3		512		25, 250
 40 * AD5241		1		256		10, 100, 1M
 41 * AD5246		1		128		5, 10, 50, 100
 42 * AD5247		1		128		5, 10, 50, 100
 43 * AD5245		1		256		5, 10, 50, 100
 44 * AD5243		2		256		2.5, 10, 50, 100
 45 * AD5248		2		256		2.5, 10, 50, 100
 46 * AD5242		2		256		20, 50, 200
 47 * AD5280		1		256		20, 50, 200
 48 * AD5282		2		256		20, 50, 200
 49 * ADN2860		3		512		25, 250
 50 * AD5273		1		64		1, 10, 50, 100 (OTP)
 51 * AD5171		1		64		5, 10, 50, 100 (OTP)
 52 * AD5170		1		256		2.5, 10, 50, 100 (OTP)
 53 * AD5172		2		256		2.5, 10, 50, 100 (OTP)
 54 * AD5173		2		256		2.5, 10, 50, 100 (OTP)
 55 * AD5270		1		1024		20, 50, 100 (50-TP)
 56 * AD5271		1		256		20, 50, 100 (50-TP)
 57 * AD5272		1		1024		20, 50, 100 (50-TP)
 58 * AD5274		1		256		20, 50, 100 (50-TP)
 59 *
 60 * See Documentation/misc-devices/ad525x_dpot.txt for more info.
 61 *
 62 * derived from ad5258.c
 63 * Copyright (c) 2009 Cyber Switching, Inc.
 64 * Author: Chris Verges <chrisv@cyberswitching.com>
 65 *
 66 * derived from ad5252.c
 67 * Copyright (c) 2006-2011 Michael Hennerich <hennerich@blackfin.uclinux.org>
 68 *
 69 * Licensed under the GPL-2 or later.
 70 */
 71
 72#include <linux/module.h>
 73#include <linux/device.h>
 74#include <linux/kernel.h>
 
 75#include <linux/delay.h>
 76#include <linux/slab.h>
 77
 
 
 78#include "ad525x_dpot.h"
 79
 80/*
 81 * Client data (each client gets its own)
 82 */
 83
 84struct dpot_data {
 85	struct ad_dpot_bus_data	bdata;
 86	struct mutex update_lock;
 87	unsigned rdac_mask;
 88	unsigned max_pos;
 89	unsigned long devid;
 90	unsigned uid;
 91	unsigned feat;
 92	unsigned wipers;
 93	u16 rdac_cache[MAX_RDACS];
 94	DECLARE_BITMAP(otp_en_mask, MAX_RDACS);
 95};
 96
 97static inline int dpot_read_d8(struct dpot_data *dpot)
 98{
 99	return dpot->bdata.bops->read_d8(dpot->bdata.client);
100}
101
102static 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
107static 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
112static 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
117static 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
122static 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
127static s32 dpot_read_spi(struct dpot_data *dpot, u8 reg)
128{
129	unsigned 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 (dpot->uid == DPOT_UID(AD5291_ID))
144				value = value >> 2;
145
146			return value;
147		} else if (dpot->uid == DPOT_UID(AD5270_ID) ||
148			dpot->uid == DPOT_UID(AD5271_ID)) {
149
150			value = dpot_read_r8d8(dpot,
151				DPOT_AD5270_1_2_4_READ_RDAC << 2);
152
153			if (value < 0)
154				return value;
155
156			if (dpot->uid == DPOT_UID(AD5271_ID))
157				value = value >> 2;
158
159			return value;
160		}
161
162		ctrl = DPOT_SPI_READ_RDAC;
163	} else if (reg & DPOT_ADDR_EEPROM) {
164		ctrl = DPOT_SPI_READ_EEPROM;
165	}
166
167	if (dpot->feat & F_SPI_16BIT)
168		return dpot_read_r8d8(dpot, ctrl);
169	else if (dpot->feat & F_SPI_24BIT)
170		return dpot_read_r8d16(dpot, ctrl);
171
172	return -EFAULT;
173}
174
175static s32 dpot_read_i2c(struct dpot_data *dpot, u8 reg)
176{
177	int value;
178	unsigned ctrl = 0;
179	switch (dpot->uid) {
180	case DPOT_UID(AD5246_ID):
181	case DPOT_UID(AD5247_ID):
182		return dpot_read_d8(dpot);
183	case DPOT_UID(AD5245_ID):
184	case DPOT_UID(AD5241_ID):
185	case DPOT_UID(AD5242_ID):
186	case DPOT_UID(AD5243_ID):
187	case DPOT_UID(AD5248_ID):
188	case DPOT_UID(AD5280_ID):
189	case DPOT_UID(AD5282_ID):
190		ctrl = ((reg & DPOT_RDAC_MASK) == DPOT_RDAC0) ?
191			0 : DPOT_AD5282_RDAC_AB;
192		return dpot_read_r8d8(dpot, ctrl);
193	case DPOT_UID(AD5170_ID):
194	case DPOT_UID(AD5171_ID):
195	case DPOT_UID(AD5273_ID):
196			return dpot_read_d8(dpot);
197	case DPOT_UID(AD5172_ID):
198	case DPOT_UID(AD5173_ID):
199		ctrl = ((reg & DPOT_RDAC_MASK) == DPOT_RDAC0) ?
200			0 : DPOT_AD5172_3_A0;
201		return dpot_read_r8d8(dpot, ctrl);
202	case DPOT_UID(AD5272_ID):
203	case DPOT_UID(AD5274_ID):
204			dpot_write_r8d8(dpot,
205				(DPOT_AD5270_1_2_4_READ_RDAC << 2), 0);
206
207			value = dpot_read_r8d16(dpot,
208				DPOT_AD5270_1_2_4_RDAC << 2);
209
210			if (value < 0)
211				return value;
212			/*
213			 * AD5272/AD5274 returns high byte first, however
214			 * underling smbus expects low byte first.
215			 */
216			value = swab16(value);
217
218			if (dpot->uid == DPOT_UID(AD5271_ID))
219				value = value >> 2;
220		return value;
221	default:
222		if ((reg & DPOT_REG_TOL) || (dpot->max_pos > 256))
223			return dpot_read_r8d16(dpot, (reg & 0xF8) |
224					((reg & 0x7) << 1));
225		else
226			return dpot_read_r8d8(dpot, reg);
227	}
228}
229
230static s32 dpot_read(struct dpot_data *dpot, u8 reg)
231{
232	if (dpot->feat & F_SPI)
233		return dpot_read_spi(dpot, reg);
234	else
235		return dpot_read_i2c(dpot, reg);
236}
237
238static s32 dpot_write_spi(struct dpot_data *dpot, u8 reg, u16 value)
239{
240	unsigned val = 0;
241
242	if (!(reg & (DPOT_ADDR_EEPROM | DPOT_ADDR_CMD | DPOT_ADDR_OTP))) {
243		if (dpot->feat & F_RDACS_WONLY)
244			dpot->rdac_cache[reg & DPOT_RDAC_MASK] = value;
245
246		if (dpot->feat & F_AD_APPDATA) {
247			if (dpot->feat & F_SPI_8BIT) {
248				val = ((reg & DPOT_RDAC_MASK) <<
249					DPOT_MAX_POS(dpot->devid)) |
250					value;
251				return dpot_write_d8(dpot, val);
252			} else if (dpot->feat & F_SPI_16BIT) {
253				val = ((reg & DPOT_RDAC_MASK) <<
254					DPOT_MAX_POS(dpot->devid)) |
255					value;
256				return dpot_write_r8d8(dpot, val >> 8,
257					val & 0xFF);
258			} else
259				BUG();
260		} else {
261			if (dpot->uid == DPOT_UID(AD5291_ID) ||
262				dpot->uid == DPOT_UID(AD5292_ID) ||
263				dpot->uid == DPOT_UID(AD5293_ID)) {
264
265				dpot_write_r8d8(dpot, DPOT_AD5291_CTRLREG << 2,
266						DPOT_AD5291_UNLOCK_CMD);
267
268				if (dpot->uid == DPOT_UID(AD5291_ID))
269					value = value << 2;
270
271				return dpot_write_r8d8(dpot,
272					(DPOT_AD5291_RDAC << 2) |
273					(value >> 8), value & 0xFF);
274			} else if (dpot->uid == DPOT_UID(AD5270_ID) ||
275				dpot->uid == DPOT_UID(AD5271_ID)) {
276				dpot_write_r8d8(dpot,
277						DPOT_AD5270_1_2_4_CTRLREG << 2,
278						DPOT_AD5270_1_2_4_UNLOCK_CMD);
279
280				if (dpot->uid == DPOT_UID(AD5271_ID))
281					value = value << 2;
282
283				return dpot_write_r8d8(dpot,
284					(DPOT_AD5270_1_2_4_RDAC << 2) |
285					(value >> 8), value & 0xFF);
286			}
287			val = DPOT_SPI_RDAC | (reg & DPOT_RDAC_MASK);
288		}
289	} else if (reg & DPOT_ADDR_EEPROM) {
290		val = DPOT_SPI_EEPROM | (reg & DPOT_RDAC_MASK);
291	} else if (reg & DPOT_ADDR_CMD) {
292		switch (reg) {
293		case DPOT_DEC_ALL_6DB:
294			val = DPOT_SPI_DEC_ALL_6DB;
295			break;
296		case DPOT_INC_ALL_6DB:
297			val = DPOT_SPI_INC_ALL_6DB;
298			break;
299		case DPOT_DEC_ALL:
300			val = DPOT_SPI_DEC_ALL;
301			break;
302		case DPOT_INC_ALL:
303			val = DPOT_SPI_INC_ALL;
304			break;
305		}
306	} else if (reg & DPOT_ADDR_OTP) {
307		if (dpot->uid == DPOT_UID(AD5291_ID) ||
308			dpot->uid == DPOT_UID(AD5292_ID)) {
309			return dpot_write_r8d8(dpot,
310				DPOT_AD5291_STORE_XTPM << 2, 0);
311		} else if (dpot->uid == DPOT_UID(AD5270_ID) ||
312			dpot->uid == DPOT_UID(AD5271_ID)) {
313			return dpot_write_r8d8(dpot,
314				DPOT_AD5270_1_2_4_STORE_XTPM << 2, 0);
315		}
316	} else
317		BUG();
318
319	if (dpot->feat & F_SPI_16BIT)
320		return dpot_write_r8d8(dpot, val, value);
321	else if (dpot->feat & F_SPI_24BIT)
322		return dpot_write_r8d16(dpot, val, value);
323
324	return -EFAULT;
325}
326
327static s32 dpot_write_i2c(struct dpot_data *dpot, u8 reg, u16 value)
328{
329	/* Only write the instruction byte for certain commands */
330	unsigned tmp = 0, ctrl = 0;
331
332	switch (dpot->uid) {
333	case DPOT_UID(AD5246_ID):
334	case DPOT_UID(AD5247_ID):
335		return dpot_write_d8(dpot, value);
336		break;
337
338	case DPOT_UID(AD5245_ID):
339	case DPOT_UID(AD5241_ID):
340	case DPOT_UID(AD5242_ID):
341	case DPOT_UID(AD5243_ID):
342	case DPOT_UID(AD5248_ID):
343	case DPOT_UID(AD5280_ID):
344	case DPOT_UID(AD5282_ID):
345		ctrl = ((reg & DPOT_RDAC_MASK) == DPOT_RDAC0) ?
346			0 : DPOT_AD5282_RDAC_AB;
347		return dpot_write_r8d8(dpot, ctrl, value);
348		break;
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		break;
359	case DPOT_UID(AD5172_ID):
360	case DPOT_UID(AD5173_ID):
361		ctrl = ((reg & DPOT_RDAC_MASK) == DPOT_RDAC0) ?
362			0 : DPOT_AD5172_3_A0;
363		if (reg & DPOT_ADDR_OTP) {
364			tmp = dpot_read_r8d16(dpot, ctrl);
365			if (tmp >> 14) /* Ready to Program? */
366				return -EFAULT;
367			ctrl |= DPOT_AD5170_2_3_FUSE;
368		}
369		return dpot_write_r8d8(dpot, ctrl, value);
370		break;
371	case DPOT_UID(AD5170_ID):
372		if (reg & DPOT_ADDR_OTP) {
373			tmp = dpot_read_r8d16(dpot, tmp);
374			if (tmp >> 14) /* Ready to Program? */
375				return -EFAULT;
376			ctrl = DPOT_AD5170_2_3_FUSE;
377		}
378		return dpot_write_r8d8(dpot, ctrl, value);
379		break;
380	case DPOT_UID(AD5272_ID):
381	case DPOT_UID(AD5274_ID):
382		dpot_write_r8d8(dpot, DPOT_AD5270_1_2_4_CTRLREG << 2,
383				DPOT_AD5270_1_2_4_UNLOCK_CMD);
384
385		if (reg & DPOT_ADDR_OTP)
386			return dpot_write_r8d8(dpot,
387					DPOT_AD5270_1_2_4_STORE_XTPM << 2, 0);
388
389		if (dpot->uid == DPOT_UID(AD5274_ID))
390			value = value << 2;
391
392		return dpot_write_r8d8(dpot, (DPOT_AD5270_1_2_4_RDAC << 2) |
393				       (value >> 8), value & 0xFF);
394		break;
395	default:
396		if (reg & DPOT_ADDR_CMD)
397			return dpot_write_d8(dpot, reg);
398
399		if (dpot->max_pos > 256)
400			return dpot_write_r8d16(dpot, (reg & 0xF8) |
401						((reg & 0x7) << 1), value);
402		else
403			/* All other registers require instruction + data bytes */
404			return dpot_write_r8d8(dpot, reg, value);
405	}
406}
407
408static s32 dpot_write(struct dpot_data *dpot, u8 reg, u16 value)
409{
410	if (dpot->feat & F_SPI)
411		return dpot_write_spi(dpot, reg, value);
412	else
413		return dpot_write_i2c(dpot, reg, value);
414}
415
416/* sysfs functions */
417
418static ssize_t sysfs_show_reg(struct device *dev,
419			      struct device_attribute *attr,
420			      char *buf, u32 reg)
421{
422	struct dpot_data *data = dev_get_drvdata(dev);
423	s32 value;
424
425	if (reg & DPOT_ADDR_OTP_EN)
426		return sprintf(buf, "%s\n",
427			test_bit(DPOT_RDAC_MASK & reg, data->otp_en_mask) ?
428			"enabled" : "disabled");
429
430
431	mutex_lock(&data->update_lock);
432	value = dpot_read(data, reg);
433	mutex_unlock(&data->update_lock);
434
435	if (value < 0)
436		return -EINVAL;
437	/*
438	 * Let someone else deal with converting this ...
439	 * the tolerance is a two-byte value where the MSB
440	 * is a sign + integer value, and the LSB is a
441	 * decimal value.  See page 18 of the AD5258
442	 * datasheet (Rev. A) for more details.
443	 */
444
445	if (reg & DPOT_REG_TOL)
446		return sprintf(buf, "0x%04x\n", value & 0xFFFF);
447	else
448		return sprintf(buf, "%u\n", value & data->rdac_mask);
449}
450
451static ssize_t sysfs_set_reg(struct device *dev,
452			     struct device_attribute *attr,
453			     const char *buf, size_t count, u32 reg)
454{
455	struct dpot_data *data = dev_get_drvdata(dev);
456	unsigned long value;
457	int err;
458
459	if (reg & DPOT_ADDR_OTP_EN) {
460		if (!strncmp(buf, "enabled", sizeof("enabled")))
461			set_bit(DPOT_RDAC_MASK & reg, data->otp_en_mask);
462		else
463			clear_bit(DPOT_RDAC_MASK & reg, data->otp_en_mask);
464
465		return count;
466	}
467
468	if ((reg & DPOT_ADDR_OTP) &&
469		!test_bit(DPOT_RDAC_MASK & reg, data->otp_en_mask))
470		return -EPERM;
471
472	err = kstrtoul(buf, 10, &value);
473	if (err)
474		return err;
475
476	if (value > data->rdac_mask)
477		value = data->rdac_mask;
478
479	mutex_lock(&data->update_lock);
480	dpot_write(data, reg, value);
481	if (reg & DPOT_ADDR_EEPROM)
482		msleep(26);	/* Sleep while the EEPROM updates */
483	else if (reg & DPOT_ADDR_OTP)
484		msleep(400);	/* Sleep while the OTP updates */
485	mutex_unlock(&data->update_lock);
486
487	return count;
488}
489
490static ssize_t sysfs_do_cmd(struct device *dev,
491			    struct device_attribute *attr,
492			    const char *buf, size_t count, u32 reg)
493{
494	struct dpot_data *data = dev_get_drvdata(dev);
495
496	mutex_lock(&data->update_lock);
497	dpot_write(data, reg, 0);
498	mutex_unlock(&data->update_lock);
499
500	return count;
501}
502
503/* ------------------------------------------------------------------------- */
504
505#define DPOT_DEVICE_SHOW(_name, _reg) static ssize_t \
506show_##_name(struct device *dev, \
507			  struct device_attribute *attr, char *buf) \
508{ \
509	return sysfs_show_reg(dev, attr, buf, _reg); \
510}
511
512#define DPOT_DEVICE_SET(_name, _reg) static ssize_t \
513set_##_name(struct device *dev, \
514			 struct device_attribute *attr, \
515			 const char *buf, size_t count) \
516{ \
517	return sysfs_set_reg(dev, attr, buf, count, _reg); \
518}
519
520#define DPOT_DEVICE_SHOW_SET(name, reg) \
521DPOT_DEVICE_SHOW(name, reg) \
522DPOT_DEVICE_SET(name, reg) \
523static DEVICE_ATTR(name, S_IWUSR | S_IRUGO, show_##name, set_##name);
524
525#define DPOT_DEVICE_SHOW_ONLY(name, reg) \
526DPOT_DEVICE_SHOW(name, reg) \
527static DEVICE_ATTR(name, S_IWUSR | S_IRUGO, show_##name, NULL);
528
529DPOT_DEVICE_SHOW_SET(rdac0, DPOT_ADDR_RDAC | DPOT_RDAC0);
530DPOT_DEVICE_SHOW_SET(eeprom0, DPOT_ADDR_EEPROM | DPOT_RDAC0);
531DPOT_DEVICE_SHOW_ONLY(tolerance0, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC0);
532DPOT_DEVICE_SHOW_SET(otp0, DPOT_ADDR_OTP | DPOT_RDAC0);
533DPOT_DEVICE_SHOW_SET(otp0en, DPOT_ADDR_OTP_EN | DPOT_RDAC0);
534
535DPOT_DEVICE_SHOW_SET(rdac1, DPOT_ADDR_RDAC | DPOT_RDAC1);
536DPOT_DEVICE_SHOW_SET(eeprom1, DPOT_ADDR_EEPROM | DPOT_RDAC1);
537DPOT_DEVICE_SHOW_ONLY(tolerance1, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC1);
538DPOT_DEVICE_SHOW_SET(otp1, DPOT_ADDR_OTP | DPOT_RDAC1);
539DPOT_DEVICE_SHOW_SET(otp1en, DPOT_ADDR_OTP_EN | DPOT_RDAC1);
540
541DPOT_DEVICE_SHOW_SET(rdac2, DPOT_ADDR_RDAC | DPOT_RDAC2);
542DPOT_DEVICE_SHOW_SET(eeprom2, DPOT_ADDR_EEPROM | DPOT_RDAC2);
543DPOT_DEVICE_SHOW_ONLY(tolerance2, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC2);
544DPOT_DEVICE_SHOW_SET(otp2, DPOT_ADDR_OTP | DPOT_RDAC2);
545DPOT_DEVICE_SHOW_SET(otp2en, DPOT_ADDR_OTP_EN | DPOT_RDAC2);
546
547DPOT_DEVICE_SHOW_SET(rdac3, DPOT_ADDR_RDAC | DPOT_RDAC3);
548DPOT_DEVICE_SHOW_SET(eeprom3, DPOT_ADDR_EEPROM | DPOT_RDAC3);
549DPOT_DEVICE_SHOW_ONLY(tolerance3, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC3);
550DPOT_DEVICE_SHOW_SET(otp3, DPOT_ADDR_OTP | DPOT_RDAC3);
551DPOT_DEVICE_SHOW_SET(otp3en, DPOT_ADDR_OTP_EN | DPOT_RDAC3);
552
553DPOT_DEVICE_SHOW_SET(rdac4, DPOT_ADDR_RDAC | DPOT_RDAC4);
554DPOT_DEVICE_SHOW_SET(eeprom4, DPOT_ADDR_EEPROM | DPOT_RDAC4);
555DPOT_DEVICE_SHOW_ONLY(tolerance4, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC4);
556DPOT_DEVICE_SHOW_SET(otp4, DPOT_ADDR_OTP | DPOT_RDAC4);
557DPOT_DEVICE_SHOW_SET(otp4en, DPOT_ADDR_OTP_EN | DPOT_RDAC4);
558
559DPOT_DEVICE_SHOW_SET(rdac5, DPOT_ADDR_RDAC | DPOT_RDAC5);
560DPOT_DEVICE_SHOW_SET(eeprom5, DPOT_ADDR_EEPROM | DPOT_RDAC5);
561DPOT_DEVICE_SHOW_ONLY(tolerance5, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC5);
562DPOT_DEVICE_SHOW_SET(otp5, DPOT_ADDR_OTP | DPOT_RDAC5);
563DPOT_DEVICE_SHOW_SET(otp5en, DPOT_ADDR_OTP_EN | DPOT_RDAC5);
564
565static const struct attribute *dpot_attrib_wipers[] = {
566	&dev_attr_rdac0.attr,
567	&dev_attr_rdac1.attr,
568	&dev_attr_rdac2.attr,
569	&dev_attr_rdac3.attr,
570	&dev_attr_rdac4.attr,
571	&dev_attr_rdac5.attr,
572	NULL
573};
574
575static const struct attribute *dpot_attrib_eeprom[] = {
576	&dev_attr_eeprom0.attr,
577	&dev_attr_eeprom1.attr,
578	&dev_attr_eeprom2.attr,
579	&dev_attr_eeprom3.attr,
580	&dev_attr_eeprom4.attr,
581	&dev_attr_eeprom5.attr,
582	NULL
583};
584
585static const struct attribute *dpot_attrib_otp[] = {
586	&dev_attr_otp0.attr,
587	&dev_attr_otp1.attr,
588	&dev_attr_otp2.attr,
589	&dev_attr_otp3.attr,
590	&dev_attr_otp4.attr,
591	&dev_attr_otp5.attr,
592	NULL
593};
594
595static const struct attribute *dpot_attrib_otp_en[] = {
596	&dev_attr_otp0en.attr,
597	&dev_attr_otp1en.attr,
598	&dev_attr_otp2en.attr,
599	&dev_attr_otp3en.attr,
600	&dev_attr_otp4en.attr,
601	&dev_attr_otp5en.attr,
602	NULL
603};
604
605static const struct attribute *dpot_attrib_tolerance[] = {
606	&dev_attr_tolerance0.attr,
607	&dev_attr_tolerance1.attr,
608	&dev_attr_tolerance2.attr,
609	&dev_attr_tolerance3.attr,
610	&dev_attr_tolerance4.attr,
611	&dev_attr_tolerance5.attr,
612	NULL
613};
614
615/* ------------------------------------------------------------------------- */
616
617#define DPOT_DEVICE_DO_CMD(_name, _cmd) static ssize_t \
618set_##_name(struct device *dev, \
619			 struct device_attribute *attr, \
620			 const char *buf, size_t count) \
621{ \
622	return sysfs_do_cmd(dev, attr, buf, count, _cmd); \
623} \
624static DEVICE_ATTR(_name, S_IWUSR | S_IRUGO, NULL, set_##_name);
625
626DPOT_DEVICE_DO_CMD(inc_all, DPOT_INC_ALL);
627DPOT_DEVICE_DO_CMD(dec_all, DPOT_DEC_ALL);
628DPOT_DEVICE_DO_CMD(inc_all_6db, DPOT_INC_ALL_6DB);
629DPOT_DEVICE_DO_CMD(dec_all_6db, DPOT_DEC_ALL_6DB);
630
631static struct attribute *ad525x_attributes_commands[] = {
632	&dev_attr_inc_all.attr,
633	&dev_attr_dec_all.attr,
634	&dev_attr_inc_all_6db.attr,
635	&dev_attr_dec_all_6db.attr,
636	NULL
637};
638
639static const struct attribute_group ad525x_group_commands = {
640	.attrs = ad525x_attributes_commands,
641};
642
643static int ad_dpot_add_files(struct device *dev,
644		unsigned features, unsigned rdac)
645{
646	int err = sysfs_create_file(&dev->kobj,
647		dpot_attrib_wipers[rdac]);
648	if (features & F_CMD_EEP)
649		err |= sysfs_create_file(&dev->kobj,
650			dpot_attrib_eeprom[rdac]);
651	if (features & F_CMD_TOL)
652		err |= sysfs_create_file(&dev->kobj,
653			dpot_attrib_tolerance[rdac]);
654	if (features & F_CMD_OTP) {
655		err |= sysfs_create_file(&dev->kobj,
656			dpot_attrib_otp_en[rdac]);
657		err |= sysfs_create_file(&dev->kobj,
658			dpot_attrib_otp[rdac]);
659	}
660
661	if (err)
662		dev_err(dev, "failed to register sysfs hooks for RDAC%d\n",
663			rdac);
664
665	return err;
666}
667
668static inline void ad_dpot_remove_files(struct device *dev,
669		unsigned features, unsigned rdac)
670{
671	sysfs_remove_file(&dev->kobj,
672		dpot_attrib_wipers[rdac]);
673	if (features & F_CMD_EEP)
674		sysfs_remove_file(&dev->kobj,
675			dpot_attrib_eeprom[rdac]);
676	if (features & F_CMD_TOL)
677		sysfs_remove_file(&dev->kobj,
678			dpot_attrib_tolerance[rdac]);
679	if (features & F_CMD_OTP) {
680		sysfs_remove_file(&dev->kobj,
681			dpot_attrib_otp_en[rdac]);
682		sysfs_remove_file(&dev->kobj,
683			dpot_attrib_otp[rdac]);
684	}
685}
686
687int ad_dpot_probe(struct device *dev,
688		struct ad_dpot_bus_data *bdata, unsigned long devid,
689			    const char *name)
690{
691
692	struct dpot_data *data;
693	int i, err = 0;
694
695	data = kzalloc(sizeof(struct dpot_data), GFP_KERNEL);
696	if (!data) {
697		err = -ENOMEM;
698		goto exit;
699	}
700
701	dev_set_drvdata(dev, data);
702	mutex_init(&data->update_lock);
703
704	data->bdata = *bdata;
705	data->devid = devid;
706
707	data->max_pos = 1 << DPOT_MAX_POS(devid);
708	data->rdac_mask = data->max_pos - 1;
709	data->feat = DPOT_FEAT(devid);
710	data->uid = DPOT_UID(devid);
711	data->wipers = DPOT_WIPERS(devid);
712
713	for (i = DPOT_RDAC0; i < MAX_RDACS; i++)
714		if (data->wipers & (1 << i)) {
715			err = ad_dpot_add_files(dev, data->feat, i);
716			if (err)
717				goto exit_remove_files;
718			/* power-up midscale */
719			if (data->feat & F_RDACS_WONLY)
720				data->rdac_cache[i] = data->max_pos / 2;
721		}
722
723	if (data->feat & F_CMD_INC)
724		err = sysfs_create_group(&dev->kobj, &ad525x_group_commands);
725
726	if (err) {
727		dev_err(dev, "failed to register sysfs hooks\n");
728		goto exit_free;
729	}
730
731	dev_info(dev, "%s %d-Position Digital Potentiometer registered\n",
732		 name, data->max_pos);
733
734	return 0;
735
736exit_remove_files:
737	for (i = DPOT_RDAC0; i < MAX_RDACS; i++)
738		if (data->wipers & (1 << i))
739			ad_dpot_remove_files(dev, data->feat, i);
740
741exit_free:
742	kfree(data);
743	dev_set_drvdata(dev, NULL);
744exit:
745	dev_err(dev, "failed to create client for %s ID 0x%lX\n",
746		name, devid);
747	return err;
748}
749EXPORT_SYMBOL(ad_dpot_probe);
750
751int ad_dpot_remove(struct device *dev)
752{
753	struct dpot_data *data = dev_get_drvdata(dev);
754	int i;
755
756	for (i = DPOT_RDAC0; i < MAX_RDACS; i++)
757		if (data->wipers & (1 << i))
758			ad_dpot_remove_files(dev, data->feat, i);
759
760	kfree(data);
761
762	return 0;
763}
764EXPORT_SYMBOL(ad_dpot_remove);
765
766
767MODULE_AUTHOR("Chris Verges <chrisv@cyberswitching.com>, "
768	      "Michael Hennerich <hennerich@blackfin.uclinux.org>");
769MODULE_DESCRIPTION("Digital potentiometer driver");
770MODULE_LICENSE("GPL");