1 /*
2 * AD7280A Lithium Ion Battery Monitoring System
3 *
4 * Copyright 2011 Analog Devices Inc.
5 *
6 * Licensed under the GPL-2.
7 */
8
9 #include <linux/device.h>
10 #include <linux/kernel.h>
11 #include <linux/slab.h>
12 #include <linux/sysfs.h>
13 #include <linux/spi/spi.h>
14 #include <linux/err.h>
15 #include <linux/delay.h>
16 #include <linux/interrupt.h>
17 #include <linux/module.h>
18
19 #include "../iio.h"
20 #include "../sysfs.h"
21 #include "../events.h"
22
23 #include "ad7280a.h"
24
25 /* Registers */
26 #define AD7280A_CELL_VOLTAGE_1 0x0 /* D11 to D0, Read only */
27 #define AD7280A_CELL_VOLTAGE_2 0x1 /* D11 to D0, Read only */
28 #define AD7280A_CELL_VOLTAGE_3 0x2 /* D11 to D0, Read only */
29 #define AD7280A_CELL_VOLTAGE_4 0x3 /* D11 to D0, Read only */
30 #define AD7280A_CELL_VOLTAGE_5 0x4 /* D11 to D0, Read only */
31 #define AD7280A_CELL_VOLTAGE_6 0x5 /* D11 to D0, Read only */
32 #define AD7280A_AUX_ADC_1 0x6 /* D11 to D0, Read only */
33 #define AD7280A_AUX_ADC_2 0x7 /* D11 to D0, Read only */
34 #define AD7280A_AUX_ADC_3 0x8 /* D11 to D0, Read only */
35 #define AD7280A_AUX_ADC_4 0x9 /* D11 to D0, Read only */
36 #define AD7280A_AUX_ADC_5 0xA /* D11 to D0, Read only */
37 #define AD7280A_AUX_ADC_6 0xB /* D11 to D0, Read only */
38 #define AD7280A_SELF_TEST 0xC /* D11 to D0, Read only */
39 #define AD7280A_CONTROL_HB 0xD /* D15 to D8, Read/write */
40 #define AD7280A_CONTROL_LB 0xE /* D7 to D0, Read/write */
41 #define AD7280A_CELL_OVERVOLTAGE 0xF /* D7 to D0, Read/write */
42 #define AD7280A_CELL_UNDERVOLTAGE 0x10 /* D7 to D0, Read/write */
43 #define AD7280A_AUX_ADC_OVERVOLTAGE 0x11 /* D7 to D0, Read/write */
44 #define AD7280A_AUX_ADC_UNDERVOLTAGE 0x12 /* D7 to D0, Read/write */
45 #define AD7280A_ALERT 0x13 /* D7 to D0, Read/write */
46 #define AD7280A_CELL_BALANCE 0x14 /* D7 to D0, Read/write */
47 #define AD7280A_CB1_TIMER 0x15 /* D7 to D0, Read/write */
48 #define AD7280A_CB2_TIMER 0x16 /* D7 to D0, Read/write */
49 #define AD7280A_CB3_TIMER 0x17 /* D7 to D0, Read/write */
50 #define AD7280A_CB4_TIMER 0x18 /* D7 to D0, Read/write */
51 #define AD7280A_CB5_TIMER 0x19 /* D7 to D0, Read/write */
52 #define AD7280A_CB6_TIMER 0x1A /* D7 to D0, Read/write */
53 #define AD7280A_PD_TIMER 0x1B /* D7 to D0, Read/write */
54 #define AD7280A_READ 0x1C /* D7 to D0, Read/write */
55 #define AD7280A_CNVST_CONTROL 0x1D /* D7 to D0, Read/write */
56
57 /* Bits and Masks */
58 #define AD7280A_CTRL_HB_CONV_INPUT_ALL (0 << 6)
59 #define AD7280A_CTRL_HB_CONV_INPUT_6CELL_AUX1_3_4 (1 << 6)
60 #define AD7280A_CTRL_HB_CONV_INPUT_6CELL (2 << 6)
61 #define AD7280A_CTRL_HB_CONV_INPUT_SELF_TEST (3 << 6)
62 #define AD7280A_CTRL_HB_CONV_RES_READ_ALL (0 << 4)
63 #define AD7280A_CTRL_HB_CONV_RES_READ_6CELL_AUX1_3_4 (1 << 4)
64 #define AD7280A_CTRL_HB_CONV_RES_READ_6CELL (2 << 4)
65 #define AD7280A_CTRL_HB_CONV_RES_READ_NO (3 << 4)
66 #define AD7280A_CTRL_HB_CONV_START_CNVST (0 << 3)
67 #define AD7280A_CTRL_HB_CONV_START_CS (1 << 3)
68 #define AD7280A_CTRL_HB_CONV_AVG_DIS (0 << 1)
69 #define AD7280A_CTRL_HB_CONV_AVG_2 (1 << 1)
70 #define AD7280A_CTRL_HB_CONV_AVG_4 (2 << 1)
71 #define AD7280A_CTRL_HB_CONV_AVG_8 (3 << 1)
72 #define AD7280A_CTRL_HB_CONV_AVG(x) ((x) << 1)
73 #define AD7280A_CTRL_HB_PWRDN_SW (1 << 0)
74
75 #define AD7280A_CTRL_LB_SWRST (1 << 7)
76 #define AD7280A_CTRL_LB_ACQ_TIME_400ns (0 << 5)
77 #define AD7280A_CTRL_LB_ACQ_TIME_800ns (1 << 5)
78 #define AD7280A_CTRL_LB_ACQ_TIME_1200ns (2 << 5)
79 #define AD7280A_CTRL_LB_ACQ_TIME_1600ns (3 << 5)
80 #define AD7280A_CTRL_LB_ACQ_TIME(x) ((x) << 5)
81 #define AD7280A_CTRL_LB_MUST_SET (1 << 4)
82 #define AD7280A_CTRL_LB_THERMISTOR_EN (1 << 3)
83 #define AD7280A_CTRL_LB_LOCK_DEV_ADDR (1 << 2)
84 #define AD7280A_CTRL_LB_INC_DEV_ADDR (1 << 1)
85 #define AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN (1 << 0)
86
87 #define AD7280A_ALERT_GEN_STATIC_HIGH (1 << 6)
88 #define AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN (3 << 6)
89
90 #define AD7280A_ALL_CELLS (0xAD << 16)
91
92 #define AD7280A_MAX_SPI_CLK_Hz 700000 /* < 1MHz */
93 #define AD7280A_MAX_CHAIN 8
94 #define AD7280A_CELLS_PER_DEV 6
95 #define AD7280A_BITS 12
96 #define AD7280A_NUM_CH (AD7280A_AUX_ADC_6 - \
97 AD7280A_CELL_VOLTAGE_1 + 1)
98
99 #define AD7280A_DEVADDR_MASTER 0
100 #define AD7280A_DEVADDR_ALL 0x1F
101 /* 5-bit device address is sent LSB first */
102 #define AD7280A_DEVADDR(addr) (((addr & 0x1) << 4) | ((addr & 0x2) << 3) | \
103 (addr & 0x4) | ((addr & 0x8) >> 3) | \
104 ((addr & 0x10) >> 4))
105
106 /* During a read a valid write is mandatory.
107 * So writing to the highest available address (Address 0x1F)
108 * and setting the address all parts bit to 0 is recommended
109 * So the TXVAL is AD7280A_DEVADDR_ALL + CRC
110 */
111 #define AD7280A_READ_TXVAL 0xF800030A
112
113 /*
114 * AD7280 CRC
115 *
116 * P(x) = x^8 + x^5 + x^3 + x^2 + x^1 + x^0 = 0b100101111 => 0x2F
117 */
118 #define POLYNOM 0x2F
119 #define POLYNOM_ORDER 8
120 #define HIGHBIT 1 << (POLYNOM_ORDER - 1);
121
122 struct ad7280_state {
123 struct spi_device *spi;
124 struct iio_chan_spec *channels;
125 struct iio_dev_attr *iio_attr;
126 int slave_num;
127 int scan_cnt;
128 int readback_delay_us;
129 unsigned char crc_tab[256];
130 unsigned char ctrl_hb;
131 unsigned char ctrl_lb;
132 unsigned char cell_threshhigh;
133 unsigned char cell_threshlow;
134 unsigned char aux_threshhigh;
135 unsigned char aux_threshlow;
136 unsigned char cb_mask[AD7280A_MAX_CHAIN];
137 };
138
ad7280_crc8_build_table(unsigned char * crc_tab)139 static void ad7280_crc8_build_table(unsigned char *crc_tab)
140 {
141 unsigned char bit, crc;
142 int cnt, i;
143
144 for (cnt = 0; cnt < 256; cnt++) {
145 crc = cnt;
146 for (i = 0; i < 8; i++) {
147 bit = crc & HIGHBIT;
148 crc <<= 1;
149 if (bit)
150 crc ^= POLYNOM;
151 }
152 crc_tab[cnt] = crc;
153 }
154 }
155
ad7280_calc_crc8(unsigned char * crc_tab,unsigned val)156 static unsigned char ad7280_calc_crc8(unsigned char *crc_tab, unsigned val)
157 {
158 unsigned char crc;
159
160 crc = crc_tab[val >> 16 & 0xFF];
161 crc = crc_tab[crc ^ (val >> 8 & 0xFF)];
162
163 return crc ^ (val & 0xFF);
164 }
165
ad7280_check_crc(struct ad7280_state * st,unsigned val)166 static int ad7280_check_crc(struct ad7280_state *st, unsigned val)
167 {
168 unsigned char crc = ad7280_calc_crc8(st->crc_tab, val >> 10);
169
170 if (crc != ((val >> 2) & 0xFF))
171 return -EIO;
172
173 return 0;
174 }
175
176 /* After initiating a conversion sequence we need to wait until the
177 * conversion is done. The delay is typically in the range of 15..30 us
178 * however depending an the number of devices in the daisy chain and the
179 * number of averages taken, conversion delays and acquisition time options
180 * it may take up to 250us, in this case we better sleep instead of busy
181 * wait.
182 */
183
ad7280_delay(struct ad7280_state * st)184 static void ad7280_delay(struct ad7280_state *st)
185 {
186 if (st->readback_delay_us < 50)
187 udelay(st->readback_delay_us);
188 else
189 msleep(1);
190 }
191
__ad7280_read32(struct spi_device * spi,unsigned * val)192 static int __ad7280_read32(struct spi_device *spi, unsigned *val)
193 {
194 unsigned rx_buf, tx_buf = cpu_to_be32(AD7280A_READ_TXVAL);
195 int ret;
196
197 struct spi_transfer t = {
198 .tx_buf = &tx_buf,
199 .rx_buf = &rx_buf,
200 .len = 4,
201 };
202 struct spi_message m;
203
204 spi_message_init(&m);
205 spi_message_add_tail(&t, &m);
206
207 ret = spi_sync(spi, &m);
208 if (ret)
209 return ret;
210
211 *val = be32_to_cpu(rx_buf);
212
213 return 0;
214 }
215
ad7280_write(struct ad7280_state * st,unsigned devaddr,unsigned addr,bool all,unsigned val)216 static int ad7280_write(struct ad7280_state *st, unsigned devaddr,
217 unsigned addr, bool all, unsigned val)
218 {
219 unsigned reg = (devaddr << 27 | addr << 21 |
220 (val & 0xFF) << 13 | all << 12);
221
222 reg |= ad7280_calc_crc8(st->crc_tab, reg >> 11) << 3 | 0x2;
223 reg = cpu_to_be32(reg);
224
225 return spi_write(st->spi, ®, 4);
226 }
227
ad7280_read(struct ad7280_state * st,unsigned devaddr,unsigned addr)228 static int ad7280_read(struct ad7280_state *st, unsigned devaddr,
229 unsigned addr)
230 {
231 int ret;
232 unsigned tmp;
233
234 /* turns off the read operation on all parts */
235 ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
236 AD7280A_CTRL_HB_CONV_INPUT_ALL |
237 AD7280A_CTRL_HB_CONV_RES_READ_NO |
238 st->ctrl_hb);
239 if (ret)
240 return ret;
241
242 /* turns on the read operation on the addressed part */
243 ret = ad7280_write(st, devaddr, AD7280A_CONTROL_HB, 0,
244 AD7280A_CTRL_HB_CONV_INPUT_ALL |
245 AD7280A_CTRL_HB_CONV_RES_READ_ALL |
246 st->ctrl_hb);
247 if (ret)
248 return ret;
249
250 /* Set register address on the part to be read from */
251 ret = ad7280_write(st, devaddr, AD7280A_READ, 0, addr << 2);
252 if (ret)
253 return ret;
254
255 __ad7280_read32(st->spi, &tmp);
256
257 if (ad7280_check_crc(st, tmp))
258 return -EIO;
259
260 if (((tmp >> 27) != devaddr) || (((tmp >> 21) & 0x3F) != addr))
261 return -EFAULT;
262
263 return (tmp >> 13) & 0xFF;
264 }
265
ad7280_read_channel(struct ad7280_state * st,unsigned devaddr,unsigned addr)266 static int ad7280_read_channel(struct ad7280_state *st, unsigned devaddr,
267 unsigned addr)
268 {
269 int ret;
270 unsigned tmp;
271
272 ret = ad7280_write(st, devaddr, AD7280A_READ, 0, addr << 2);
273 if (ret)
274 return ret;
275
276 ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
277 AD7280A_CTRL_HB_CONV_INPUT_ALL |
278 AD7280A_CTRL_HB_CONV_RES_READ_NO |
279 st->ctrl_hb);
280 if (ret)
281 return ret;
282
283 ret = ad7280_write(st, devaddr, AD7280A_CONTROL_HB, 0,
284 AD7280A_CTRL_HB_CONV_INPUT_ALL |
285 AD7280A_CTRL_HB_CONV_RES_READ_ALL |
286 AD7280A_CTRL_HB_CONV_START_CS |
287 st->ctrl_hb);
288 if (ret)
289 return ret;
290
291 ad7280_delay(st);
292
293 __ad7280_read32(st->spi, &tmp);
294
295 if (ad7280_check_crc(st, tmp))
296 return -EIO;
297
298 if (((tmp >> 27) != devaddr) || (((tmp >> 23) & 0xF) != addr))
299 return -EFAULT;
300
301 return (tmp >> 11) & 0xFFF;
302 }
303
ad7280_read_all_channels(struct ad7280_state * st,unsigned cnt,unsigned * array)304 static int ad7280_read_all_channels(struct ad7280_state *st, unsigned cnt,
305 unsigned *array)
306 {
307 int i, ret;
308 unsigned tmp, sum = 0;
309
310 ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ, 1,
311 AD7280A_CELL_VOLTAGE_1 << 2);
312 if (ret)
313 return ret;
314
315 ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
316 AD7280A_CTRL_HB_CONV_INPUT_ALL |
317 AD7280A_CTRL_HB_CONV_RES_READ_ALL |
318 AD7280A_CTRL_HB_CONV_START_CS |
319 st->ctrl_hb);
320 if (ret)
321 return ret;
322
323 ad7280_delay(st);
324
325 for (i = 0; i < cnt; i++) {
326 __ad7280_read32(st->spi, &tmp);
327
328 if (ad7280_check_crc(st, tmp))
329 return -EIO;
330
331 if (array)
332 array[i] = tmp;
333 /* only sum cell voltages */
334 if (((tmp >> 23) & 0xF) <= AD7280A_CELL_VOLTAGE_6)
335 sum += ((tmp >> 11) & 0xFFF);
336 }
337
338 return sum;
339 }
340
ad7280_chain_setup(struct ad7280_state * st)341 static int ad7280_chain_setup(struct ad7280_state *st)
342 {
343 unsigned val, n;
344 int ret;
345
346 ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_LB, 1,
347 AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN |
348 AD7280A_CTRL_LB_LOCK_DEV_ADDR |
349 AD7280A_CTRL_LB_MUST_SET |
350 AD7280A_CTRL_LB_SWRST |
351 st->ctrl_lb);
352 if (ret)
353 return ret;
354
355 ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_LB, 1,
356 AD7280A_CTRL_LB_DAISY_CHAIN_RB_EN |
357 AD7280A_CTRL_LB_LOCK_DEV_ADDR |
358 AD7280A_CTRL_LB_MUST_SET |
359 st->ctrl_lb);
360 if (ret)
361 return ret;
362
363 ret = ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_READ, 1,
364 AD7280A_CONTROL_LB << 2);
365 if (ret)
366 return ret;
367
368 for (n = 0; n <= AD7280A_MAX_CHAIN; n++) {
369 __ad7280_read32(st->spi, &val);
370 if (val == 0)
371 return n - 1;
372
373 if (ad7280_check_crc(st, val))
374 return -EIO;
375
376 if (n != AD7280A_DEVADDR(val >> 27))
377 return -EIO;
378 }
379
380 return -EFAULT;
381 }
382
ad7280_show_balance_sw(struct device * dev,struct device_attribute * attr,char * buf)383 static ssize_t ad7280_show_balance_sw(struct device *dev,
384 struct device_attribute *attr,
385 char *buf)
386 {
387 struct iio_dev *indio_dev = dev_get_drvdata(dev);
388 struct ad7280_state *st = iio_priv(indio_dev);
389 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
390
391 return sprintf(buf, "%d\n",
392 !!(st->cb_mask[this_attr->address >> 8] &
393 (1 << ((this_attr->address & 0xFF) + 2))));
394 }
395
ad7280_store_balance_sw(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)396 static ssize_t ad7280_store_balance_sw(struct device *dev,
397 struct device_attribute *attr,
398 const char *buf,
399 size_t len)
400 {
401 struct iio_dev *indio_dev = dev_get_drvdata(dev);
402 struct ad7280_state *st = iio_priv(indio_dev);
403 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
404 bool readin;
405 int ret;
406 unsigned devaddr, ch;
407
408 ret = strtobool(buf, &readin);
409 if (ret)
410 return ret;
411
412 devaddr = this_attr->address >> 8;
413 ch = this_attr->address & 0xFF;
414
415 mutex_lock(&indio_dev->mlock);
416 if (readin)
417 st->cb_mask[devaddr] |= 1 << (ch + 2);
418 else
419 st->cb_mask[devaddr] &= ~(1 << (ch + 2));
420
421 ret = ad7280_write(st, devaddr, AD7280A_CELL_BALANCE,
422 0, st->cb_mask[devaddr]);
423 mutex_unlock(&indio_dev->mlock);
424
425 return ret ? ret : len;
426 }
427
ad7280_show_balance_timer(struct device * dev,struct device_attribute * attr,char * buf)428 static ssize_t ad7280_show_balance_timer(struct device *dev,
429 struct device_attribute *attr,
430 char *buf)
431 {
432 struct iio_dev *indio_dev = dev_get_drvdata(dev);
433 struct ad7280_state *st = iio_priv(indio_dev);
434 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
435 int ret;
436 unsigned msecs;
437
438 mutex_lock(&indio_dev->mlock);
439 ret = ad7280_read(st, this_attr->address >> 8,
440 this_attr->address & 0xFF);
441 mutex_unlock(&indio_dev->mlock);
442
443 if (ret < 0)
444 return ret;
445
446 msecs = (ret >> 3) * 71500;
447
448 return sprintf(buf, "%d\n", msecs);
449 }
450
ad7280_store_balance_timer(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)451 static ssize_t ad7280_store_balance_timer(struct device *dev,
452 struct device_attribute *attr,
453 const char *buf,
454 size_t len)
455 {
456 struct iio_dev *indio_dev = dev_get_drvdata(dev);
457 struct ad7280_state *st = iio_priv(indio_dev);
458 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
459 unsigned long val;
460 int ret;
461
462 ret = kstrtoul(buf, 10, &val);
463 if (ret)
464 return ret;
465
466 val /= 71500;
467
468 if (val > 31)
469 return -EINVAL;
470
471 mutex_lock(&indio_dev->mlock);
472 ret = ad7280_write(st, this_attr->address >> 8,
473 this_attr->address & 0xFF,
474 0, (val & 0x1F) << 3);
475 mutex_unlock(&indio_dev->mlock);
476
477 return ret ? ret : len;
478 }
479
480 static struct attribute *ad7280_attributes[AD7280A_MAX_CHAIN *
481 AD7280A_CELLS_PER_DEV * 2 + 1];
482
483 static struct attribute_group ad7280_attrs_group = {
484 .attrs = ad7280_attributes,
485 };
486
ad7280_channel_init(struct ad7280_state * st)487 static int ad7280_channel_init(struct ad7280_state *st)
488 {
489 int dev, ch, cnt;
490
491 st->channels = kcalloc((st->slave_num + 1) * 12 + 2,
492 sizeof(*st->channels), GFP_KERNEL);
493 if (st->channels == NULL)
494 return -ENOMEM;
495
496 for (dev = 0, cnt = 0; dev <= st->slave_num; dev++)
497 for (ch = AD7280A_CELL_VOLTAGE_1; ch <= AD7280A_AUX_ADC_6; ch++,
498 cnt++) {
499 if (ch < AD7280A_AUX_ADC_1) {
500 st->channels[cnt].type = IIO_VOLTAGE;
501 st->channels[cnt].differential = 1;
502 st->channels[cnt].channel = (dev * 6) + ch;
503 st->channels[cnt].channel2 =
504 st->channels[cnt].channel + 1;
505 } else {
506 st->channels[cnt].type = IIO_TEMP;
507 st->channels[cnt].channel = (dev * 6) + ch - 6;
508 }
509 st->channels[cnt].indexed = 1;
510 st->channels[cnt].info_mask =
511 IIO_CHAN_INFO_SCALE_SHARED_BIT;
512 st->channels[cnt].address =
513 AD7280A_DEVADDR(dev) << 8 | ch;
514 st->channels[cnt].scan_index = cnt;
515 st->channels[cnt].scan_type.sign = 'u';
516 st->channels[cnt].scan_type.realbits = 12;
517 st->channels[cnt].scan_type.storagebits = 32;
518 st->channels[cnt].scan_type.shift = 0;
519 }
520
521 st->channels[cnt].type = IIO_VOLTAGE;
522 st->channels[cnt].differential = 1;
523 st->channels[cnt].channel = 0;
524 st->channels[cnt].channel2 = dev * 6;
525 st->channels[cnt].address = AD7280A_ALL_CELLS;
526 st->channels[cnt].indexed = 1;
527 st->channels[cnt].info_mask = IIO_CHAN_INFO_SCALE_SHARED_BIT;
528 st->channels[cnt].scan_index = cnt;
529 st->channels[cnt].scan_type.sign = 'u';
530 st->channels[cnt].scan_type.realbits = 32;
531 st->channels[cnt].scan_type.storagebits = 32;
532 st->channels[cnt].scan_type.shift = 0;
533 cnt++;
534 st->channels[cnt].type = IIO_TIMESTAMP;
535 st->channels[cnt].channel = -1;
536 st->channels[cnt].scan_index = cnt;
537 st->channels[cnt].scan_type.sign = 's';
538 st->channels[cnt].scan_type.realbits = 64;
539 st->channels[cnt].scan_type.storagebits = 64;
540 st->channels[cnt].scan_type.shift = 0;
541
542 return cnt + 1;
543 }
544
ad7280_attr_init(struct ad7280_state * st)545 static int ad7280_attr_init(struct ad7280_state *st)
546 {
547 int dev, ch, cnt;
548
549 st->iio_attr = kzalloc(sizeof(*st->iio_attr) * (st->slave_num + 1) *
550 AD7280A_CELLS_PER_DEV * 2, GFP_KERNEL);
551 if (st->iio_attr == NULL)
552 return -ENOMEM;
553
554 for (dev = 0, cnt = 0; dev <= st->slave_num; dev++)
555 for (ch = AD7280A_CELL_VOLTAGE_1; ch <= AD7280A_CELL_VOLTAGE_6;
556 ch++, cnt++) {
557 st->iio_attr[cnt].address =
558 AD7280A_DEVADDR(dev) << 8 | ch;
559 st->iio_attr[cnt].dev_attr.attr.mode =
560 S_IWUSR | S_IRUGO;
561 st->iio_attr[cnt].dev_attr.show =
562 ad7280_show_balance_sw;
563 st->iio_attr[cnt].dev_attr.store =
564 ad7280_store_balance_sw;
565 st->iio_attr[cnt].dev_attr.attr.name =
566 kasprintf(GFP_KERNEL,
567 "in%d-in%d_balance_switch_en",
568 (dev * AD7280A_CELLS_PER_DEV) + ch,
569 (dev * AD7280A_CELLS_PER_DEV) + ch + 1);
570 ad7280_attributes[cnt] =
571 &st->iio_attr[cnt].dev_attr.attr;
572 cnt++;
573 st->iio_attr[cnt].address =
574 AD7280A_DEVADDR(dev) << 8 |
575 (AD7280A_CB1_TIMER + ch);
576 st->iio_attr[cnt].dev_attr.attr.mode =
577 S_IWUSR | S_IRUGO;
578 st->iio_attr[cnt].dev_attr.show =
579 ad7280_show_balance_timer;
580 st->iio_attr[cnt].dev_attr.store =
581 ad7280_store_balance_timer;
582 st->iio_attr[cnt].dev_attr.attr.name =
583 kasprintf(GFP_KERNEL, "in%d-in%d_balance_timer",
584 (dev * AD7280A_CELLS_PER_DEV) + ch,
585 (dev * AD7280A_CELLS_PER_DEV) + ch + 1);
586 ad7280_attributes[cnt] =
587 &st->iio_attr[cnt].dev_attr.attr;
588 }
589
590 ad7280_attributes[cnt] = NULL;
591
592 return 0;
593 }
594
ad7280_read_channel_config(struct device * dev,struct device_attribute * attr,char * buf)595 static ssize_t ad7280_read_channel_config(struct device *dev,
596 struct device_attribute *attr,
597 char *buf)
598 {
599 struct iio_dev *indio_dev = dev_get_drvdata(dev);
600 struct ad7280_state *st = iio_priv(indio_dev);
601 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
602 unsigned val;
603
604 switch ((u32) this_attr->address) {
605 case AD7280A_CELL_OVERVOLTAGE:
606 val = 1000 + (st->cell_threshhigh * 1568) / 100;
607 break;
608 case AD7280A_CELL_UNDERVOLTAGE:
609 val = 1000 + (st->cell_threshlow * 1568) / 100;
610 break;
611 case AD7280A_AUX_ADC_OVERVOLTAGE:
612 val = (st->aux_threshhigh * 196) / 10;
613 break;
614 case AD7280A_AUX_ADC_UNDERVOLTAGE:
615 val = (st->aux_threshlow * 196) / 10;
616 break;
617 default:
618 return -EINVAL;
619 }
620
621 return sprintf(buf, "%d\n", val);
622 }
623
ad7280_write_channel_config(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)624 static ssize_t ad7280_write_channel_config(struct device *dev,
625 struct device_attribute *attr,
626 const char *buf,
627 size_t len)
628 {
629 struct iio_dev *indio_dev = dev_get_drvdata(dev);
630 struct ad7280_state *st = iio_priv(indio_dev);
631 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
632
633 long val;
634 int ret;
635
636 ret = strict_strtol(buf, 10, &val);
637 if (ret)
638 return ret;
639
640 switch ((u32) this_attr->address) {
641 case AD7280A_CELL_OVERVOLTAGE:
642 case AD7280A_CELL_UNDERVOLTAGE:
643 val = ((val - 1000) * 100) / 1568; /* LSB 15.68mV */
644 break;
645 case AD7280A_AUX_ADC_OVERVOLTAGE:
646 case AD7280A_AUX_ADC_UNDERVOLTAGE:
647 val = (val * 10) / 196; /* LSB 19.6mV */
648 break;
649 default:
650 return -EFAULT;
651 }
652
653 val = clamp(val, 0L, 0xFFL);
654
655 mutex_lock(&indio_dev->mlock);
656 switch ((u32) this_attr->address) {
657 case AD7280A_CELL_OVERVOLTAGE:
658 st->cell_threshhigh = val;
659 break;
660 case AD7280A_CELL_UNDERVOLTAGE:
661 st->cell_threshlow = val;
662 break;
663 case AD7280A_AUX_ADC_OVERVOLTAGE:
664 st->aux_threshhigh = val;
665 break;
666 case AD7280A_AUX_ADC_UNDERVOLTAGE:
667 st->aux_threshlow = val;
668 break;
669 }
670
671 ret = ad7280_write(st, AD7280A_DEVADDR_MASTER,
672 this_attr->address, 1, val);
673
674 mutex_unlock(&indio_dev->mlock);
675
676 return ret ? ret : len;
677 }
678
ad7280_event_handler(int irq,void * private)679 static irqreturn_t ad7280_event_handler(int irq, void *private)
680 {
681 struct iio_dev *indio_dev = private;
682 struct ad7280_state *st = iio_priv(indio_dev);
683 unsigned *channels;
684 int i, ret;
685
686 channels = kcalloc(st->scan_cnt, sizeof(*channels), GFP_KERNEL);
687 if (channels == NULL)
688 return IRQ_HANDLED;
689
690 ret = ad7280_read_all_channels(st, st->scan_cnt, channels);
691 if (ret < 0)
692 goto out;
693
694 for (i = 0; i < st->scan_cnt; i++) {
695 if (((channels[i] >> 23) & 0xF) <= AD7280A_CELL_VOLTAGE_6) {
696 if (((channels[i] >> 11) & 0xFFF) >=
697 st->cell_threshhigh)
698 iio_push_event(indio_dev,
699 IIO_EVENT_CODE(IIO_VOLTAGE,
700 1,
701 0,
702 IIO_EV_DIR_RISING,
703 IIO_EV_TYPE_THRESH,
704 0, 0, 0),
705 iio_get_time_ns());
706 else if (((channels[i] >> 11) & 0xFFF) <=
707 st->cell_threshlow)
708 iio_push_event(indio_dev,
709 IIO_EVENT_CODE(IIO_VOLTAGE,
710 1,
711 0,
712 IIO_EV_DIR_FALLING,
713 IIO_EV_TYPE_THRESH,
714 0, 0, 0),
715 iio_get_time_ns());
716 } else {
717 if (((channels[i] >> 11) & 0xFFF) >= st->aux_threshhigh)
718 iio_push_event(indio_dev,
719 IIO_UNMOD_EVENT_CODE(IIO_TEMP,
720 0,
721 IIO_EV_TYPE_THRESH,
722 IIO_EV_DIR_RISING),
723 iio_get_time_ns());
724 else if (((channels[i] >> 11) & 0xFFF) <=
725 st->aux_threshlow)
726 iio_push_event(indio_dev,
727 IIO_UNMOD_EVENT_CODE(IIO_TEMP,
728 0,
729 IIO_EV_TYPE_THRESH,
730 IIO_EV_DIR_FALLING),
731 iio_get_time_ns());
732 }
733 }
734
735 out:
736 kfree(channels);
737
738 return IRQ_HANDLED;
739 }
740
741 static IIO_DEVICE_ATTR_NAMED(in_thresh_low_value,
742 in_voltage-voltage_thresh_low_value,
743 S_IRUGO | S_IWUSR,
744 ad7280_read_channel_config,
745 ad7280_write_channel_config,
746 AD7280A_CELL_UNDERVOLTAGE);
747
748 static IIO_DEVICE_ATTR_NAMED(in_thresh_high_value,
749 in_voltage-voltage_thresh_high_value,
750 S_IRUGO | S_IWUSR,
751 ad7280_read_channel_config,
752 ad7280_write_channel_config,
753 AD7280A_CELL_OVERVOLTAGE);
754
755 static IIO_DEVICE_ATTR(in_temp_thresh_low_value,
756 S_IRUGO | S_IWUSR,
757 ad7280_read_channel_config,
758 ad7280_write_channel_config,
759 AD7280A_AUX_ADC_UNDERVOLTAGE);
760
761 static IIO_DEVICE_ATTR(in_temp_thresh_high_value,
762 S_IRUGO | S_IWUSR,
763 ad7280_read_channel_config,
764 ad7280_write_channel_config,
765 AD7280A_AUX_ADC_OVERVOLTAGE);
766
767
768 static struct attribute *ad7280_event_attributes[] = {
769 &iio_dev_attr_in_thresh_low_value.dev_attr.attr,
770 &iio_dev_attr_in_thresh_high_value.dev_attr.attr,
771 &iio_dev_attr_in_temp_thresh_low_value.dev_attr.attr,
772 &iio_dev_attr_in_temp_thresh_high_value.dev_attr.attr,
773 NULL,
774 };
775
776 static struct attribute_group ad7280_event_attrs_group = {
777 .attrs = ad7280_event_attributes,
778 };
779
ad7280_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long m)780 static int ad7280_read_raw(struct iio_dev *indio_dev,
781 struct iio_chan_spec const *chan,
782 int *val,
783 int *val2,
784 long m)
785 {
786 struct ad7280_state *st = iio_priv(indio_dev);
787 unsigned int scale_uv;
788 int ret;
789
790 switch (m) {
791 case 0:
792 mutex_lock(&indio_dev->mlock);
793 if (chan->address == AD7280A_ALL_CELLS)
794 ret = ad7280_read_all_channels(st, st->scan_cnt, NULL);
795 else
796 ret = ad7280_read_channel(st, chan->address >> 8,
797 chan->address & 0xFF);
798 mutex_unlock(&indio_dev->mlock);
799
800 if (ret < 0)
801 return ret;
802
803 *val = ret;
804
805 return IIO_VAL_INT;
806 case IIO_CHAN_INFO_SCALE:
807 if ((chan->address & 0xFF) <= AD7280A_CELL_VOLTAGE_6)
808 scale_uv = (4000 * 1000) >> AD7280A_BITS;
809 else
810 scale_uv = (5000 * 1000) >> AD7280A_BITS;
811
812 *val = scale_uv / 1000;
813 *val2 = (scale_uv % 1000) * 1000;
814 return IIO_VAL_INT_PLUS_MICRO;
815 }
816 return -EINVAL;
817 }
818
819 static const struct iio_info ad7280_info = {
820 .read_raw = &ad7280_read_raw,
821 .event_attrs = &ad7280_event_attrs_group,
822 .attrs = &ad7280_attrs_group,
823 .driver_module = THIS_MODULE,
824 };
825
826 static const struct ad7280_platform_data ad7793_default_pdata = {
827 .acquisition_time = AD7280A_ACQ_TIME_400ns,
828 .conversion_averaging = AD7280A_CONV_AVG_DIS,
829 .thermistor_term_en = true,
830 };
831
ad7280_probe(struct spi_device * spi)832 static int __devinit ad7280_probe(struct spi_device *spi)
833 {
834 const struct ad7280_platform_data *pdata = spi->dev.platform_data;
835 struct ad7280_state *st;
836 int ret;
837 const unsigned short tACQ_ns[4] = {465, 1010, 1460, 1890};
838 const unsigned short nAVG[4] = {1, 2, 4, 8};
839 struct iio_dev *indio_dev = iio_allocate_device(sizeof(*st));
840
841 if (indio_dev == NULL)
842 return -ENOMEM;
843
844 st = iio_priv(indio_dev);
845 spi_set_drvdata(spi, indio_dev);
846 st->spi = spi;
847
848 if (!pdata)
849 pdata = &ad7793_default_pdata;
850
851 ad7280_crc8_build_table(st->crc_tab);
852
853 st->spi->max_speed_hz = AD7280A_MAX_SPI_CLK_Hz;
854 st->spi->mode = SPI_MODE_1;
855 spi_setup(st->spi);
856
857 st->ctrl_lb = AD7280A_CTRL_LB_ACQ_TIME(pdata->acquisition_time & 0x3);
858 st->ctrl_hb = AD7280A_CTRL_HB_CONV_AVG(pdata->conversion_averaging
859 & 0x3) | (pdata->thermistor_term_en ?
860 AD7280A_CTRL_LB_THERMISTOR_EN : 0);
861
862 ret = ad7280_chain_setup(st);
863 if (ret < 0)
864 goto error_free_device;
865
866 st->slave_num = ret;
867 st->scan_cnt = (st->slave_num + 1) * AD7280A_NUM_CH;
868 st->cell_threshhigh = 0xFF;
869 st->aux_threshhigh = 0xFF;
870
871 /*
872 * Total Conversion Time = ((tACQ + tCONV) *
873 * (Number of Conversions per Part)) −
874 * tACQ + ((N - 1) * tDELAY)
875 *
876 * Readback Delay = Total Conversion Time + tWAIT
877 */
878
879 st->readback_delay_us =
880 ((tACQ_ns[pdata->acquisition_time & 0x3] + 695) *
881 (AD7280A_NUM_CH * nAVG[pdata->conversion_averaging & 0x3]))
882 - tACQ_ns[pdata->acquisition_time & 0x3] +
883 st->slave_num * 250;
884
885 /* Convert to usecs */
886 st->readback_delay_us = DIV_ROUND_UP(st->readback_delay_us, 1000);
887 st->readback_delay_us += 5; /* Add tWAIT */
888
889 indio_dev->name = spi_get_device_id(spi)->name;
890 indio_dev->dev.parent = &spi->dev;
891 indio_dev->modes = INDIO_DIRECT_MODE;
892
893 ret = ad7280_channel_init(st);
894 if (ret < 0)
895 goto error_free_device;
896
897 indio_dev->num_channels = ret;
898 indio_dev->channels = st->channels;
899 indio_dev->info = &ad7280_info;
900
901 ret = ad7280_attr_init(st);
902 if (ret < 0)
903 goto error_free_channels;
904
905 ret = iio_device_register(indio_dev);
906 if (ret)
907 goto error_free_attr;
908
909 if (spi->irq > 0) {
910 ret = ad7280_write(st, AD7280A_DEVADDR_MASTER,
911 AD7280A_ALERT, 1,
912 AD7280A_ALERT_RELAY_SIG_CHAIN_DOWN);
913 if (ret)
914 goto error_unregister;
915
916 ret = ad7280_write(st, AD7280A_DEVADDR(st->slave_num),
917 AD7280A_ALERT, 0,
918 AD7280A_ALERT_GEN_STATIC_HIGH |
919 (pdata->chain_last_alert_ignore & 0xF));
920 if (ret)
921 goto error_unregister;
922
923 ret = request_threaded_irq(spi->irq,
924 NULL,
925 ad7280_event_handler,
926 IRQF_TRIGGER_FALLING |
927 IRQF_ONESHOT,
928 indio_dev->name,
929 indio_dev);
930 if (ret)
931 goto error_unregister;
932 }
933
934 return 0;
935 error_unregister:
936 iio_device_unregister(indio_dev);
937
938 error_free_attr:
939 kfree(st->iio_attr);
940
941 error_free_channels:
942 kfree(st->channels);
943
944 error_free_device:
945 iio_free_device(indio_dev);
946
947 return ret;
948 }
949
ad7280_remove(struct spi_device * spi)950 static int __devexit ad7280_remove(struct spi_device *spi)
951 {
952 struct iio_dev *indio_dev = spi_get_drvdata(spi);
953 struct ad7280_state *st = iio_priv(indio_dev);
954
955 if (spi->irq > 0)
956 free_irq(spi->irq, indio_dev);
957 iio_device_unregister(indio_dev);
958
959 ad7280_write(st, AD7280A_DEVADDR_MASTER, AD7280A_CONTROL_HB, 1,
960 AD7280A_CTRL_HB_PWRDN_SW | st->ctrl_hb);
961
962 kfree(st->channels);
963 kfree(st->iio_attr);
964 iio_free_device(indio_dev);
965
966 return 0;
967 }
968
969 static const struct spi_device_id ad7280_id[] = {
970 {"ad7280a", 0},
971 {}
972 };
973 MODULE_DEVICE_TABLE(spi, ad7280_id);
974
975 static struct spi_driver ad7280_driver = {
976 .driver = {
977 .name = "ad7280",
978 .owner = THIS_MODULE,
979 },
980 .probe = ad7280_probe,
981 .remove = __devexit_p(ad7280_remove),
982 .id_table = ad7280_id,
983 };
984 module_spi_driver(ad7280_driver);
985
986 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
987 MODULE_DESCRIPTION("Analog Devices AD7280A");
988 MODULE_LICENSE("GPL v2");
989