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1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Counter driver for the ACCES 104-QUAD-8
4  * Copyright (C) 2016 William Breathitt Gray
5  *
6  * This driver supports the ACCES 104-QUAD-8 and ACCES 104-QUAD-4.
7  */
8 #include <linux/bitops.h>
9 #include <linux/counter.h>
10 #include <linux/device.h>
11 #include <linux/errno.h>
12 #include <linux/iio/iio.h>
13 #include <linux/iio/types.h>
14 #include <linux/io.h>
15 #include <linux/ioport.h>
16 #include <linux/isa.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/moduleparam.h>
20 #include <linux/types.h>
21 
22 #define QUAD8_EXTENT 32
23 
24 static unsigned int base[max_num_isa_dev(QUAD8_EXTENT)];
25 static unsigned int num_quad8;
26 module_param_array(base, uint, &num_quad8, 0);
27 MODULE_PARM_DESC(base, "ACCES 104-QUAD-8 base addresses");
28 
29 #define QUAD8_NUM_COUNTERS 8
30 
31 /**
32  * struct quad8_iio - IIO device private data structure
33  * @counter:		instance of the counter_device
34  * @fck_prescaler:	array of filter clock prescaler configurations
35  * @preset:		array of preset values
36  * @count_mode:		array of count mode configurations
37  * @quadrature_mode:	array of quadrature mode configurations
38  * @quadrature_scale:	array of quadrature mode scale configurations
39  * @ab_enable:		array of A and B inputs enable configurations
40  * @preset_enable:	array of set_to_preset_on_index attribute configurations
41  * @synchronous_mode:	array of index function synchronous mode configurations
42  * @index_polarity:	array of index function polarity configurations
43  * @cable_fault_enable:	differential encoder cable status enable configurations
44  * @base:		base port address of the IIO device
45  */
46 struct quad8_iio {
47 	struct mutex lock;
48 	struct counter_device counter;
49 	unsigned int fck_prescaler[QUAD8_NUM_COUNTERS];
50 	unsigned int preset[QUAD8_NUM_COUNTERS];
51 	unsigned int count_mode[QUAD8_NUM_COUNTERS];
52 	unsigned int quadrature_mode[QUAD8_NUM_COUNTERS];
53 	unsigned int quadrature_scale[QUAD8_NUM_COUNTERS];
54 	unsigned int ab_enable[QUAD8_NUM_COUNTERS];
55 	unsigned int preset_enable[QUAD8_NUM_COUNTERS];
56 	unsigned int synchronous_mode[QUAD8_NUM_COUNTERS];
57 	unsigned int index_polarity[QUAD8_NUM_COUNTERS];
58 	unsigned int cable_fault_enable;
59 	unsigned int base;
60 };
61 
62 #define QUAD8_REG_CHAN_OP 0x11
63 #define QUAD8_REG_INDEX_INPUT_LEVELS 0x16
64 #define QUAD8_DIFF_ENCODER_CABLE_STATUS 0x17
65 /* Error flag */
66 #define QUAD8_FLAG_E BIT(4)
67 /* Up/Down flag */
68 #define QUAD8_FLAG_UD BIT(5)
69 /* Reset and Load Signal Decoders */
70 #define QUAD8_CTR_RLD 0x00
71 /* Counter Mode Register */
72 #define QUAD8_CTR_CMR 0x20
73 /* Input / Output Control Register */
74 #define QUAD8_CTR_IOR 0x40
75 /* Index Control Register */
76 #define QUAD8_CTR_IDR 0x60
77 /* Reset Byte Pointer (three byte data pointer) */
78 #define QUAD8_RLD_RESET_BP 0x01
79 /* Reset Counter */
80 #define QUAD8_RLD_RESET_CNTR 0x02
81 /* Reset Borrow Toggle, Carry Toggle, Compare Toggle, and Sign flags */
82 #define QUAD8_RLD_RESET_FLAGS 0x04
83 /* Reset Error flag */
84 #define QUAD8_RLD_RESET_E 0x06
85 /* Preset Register to Counter */
86 #define QUAD8_RLD_PRESET_CNTR 0x08
87 /* Transfer Counter to Output Latch */
88 #define QUAD8_RLD_CNTR_OUT 0x10
89 /* Transfer Preset Register LSB to FCK Prescaler */
90 #define QUAD8_RLD_PRESET_PSC 0x18
91 #define QUAD8_CHAN_OP_ENABLE_COUNTERS 0x00
92 #define QUAD8_CHAN_OP_RESET_COUNTERS 0x01
93 #define QUAD8_CMR_QUADRATURE_X1 0x08
94 #define QUAD8_CMR_QUADRATURE_X2 0x10
95 #define QUAD8_CMR_QUADRATURE_X4 0x18
96 
97 
quad8_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)98 static int quad8_read_raw(struct iio_dev *indio_dev,
99 	struct iio_chan_spec const *chan, int *val, int *val2, long mask)
100 {
101 	struct quad8_iio *const priv = iio_priv(indio_dev);
102 	const int base_offset = priv->base + 2 * chan->channel;
103 	int i;
104 
105 	switch (mask) {
106 	case IIO_CHAN_INFO_RAW:
107 		if (chan->type == IIO_INDEX) {
108 			*val = !!(inb(priv->base + QUAD8_REG_INDEX_INPUT_LEVELS)
109 				& BIT(chan->channel));
110 			return IIO_VAL_INT;
111 		}
112 
113 		*val = 0;
114 
115 		mutex_lock(&priv->lock);
116 
117 		/* Reset Byte Pointer; transfer Counter to Output Latch */
118 		outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP | QUAD8_RLD_CNTR_OUT,
119 		     base_offset + 1);
120 
121 		for (i = 0; i < 3; i++)
122 			*val |= (unsigned int)inb(base_offset) << (8 * i);
123 
124 		mutex_unlock(&priv->lock);
125 
126 		return IIO_VAL_INT;
127 	case IIO_CHAN_INFO_ENABLE:
128 		*val = priv->ab_enable[chan->channel];
129 		return IIO_VAL_INT;
130 	case IIO_CHAN_INFO_SCALE:
131 		*val = 1;
132 		*val2 = priv->quadrature_scale[chan->channel];
133 		return IIO_VAL_FRACTIONAL_LOG2;
134 	}
135 
136 	return -EINVAL;
137 }
138 
quad8_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)139 static int quad8_write_raw(struct iio_dev *indio_dev,
140 	struct iio_chan_spec const *chan, int val, int val2, long mask)
141 {
142 	struct quad8_iio *const priv = iio_priv(indio_dev);
143 	const int base_offset = priv->base + 2 * chan->channel;
144 	int i;
145 	unsigned int ior_cfg;
146 
147 	switch (mask) {
148 	case IIO_CHAN_INFO_RAW:
149 		if (chan->type == IIO_INDEX)
150 			return -EINVAL;
151 
152 		/* Only 24-bit values are supported */
153 		if ((unsigned int)val > 0xFFFFFF)
154 			return -EINVAL;
155 
156 		mutex_lock(&priv->lock);
157 
158 		/* Reset Byte Pointer */
159 		outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP, base_offset + 1);
160 
161 		/* Counter can only be set via Preset Register */
162 		for (i = 0; i < 3; i++)
163 			outb(val >> (8 * i), base_offset);
164 
165 		/* Transfer Preset Register to Counter */
166 		outb(QUAD8_CTR_RLD | QUAD8_RLD_PRESET_CNTR, base_offset + 1);
167 
168 		/* Reset Byte Pointer */
169 		outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP, base_offset + 1);
170 
171 		/* Set Preset Register back to original value */
172 		val = priv->preset[chan->channel];
173 		for (i = 0; i < 3; i++)
174 			outb(val >> (8 * i), base_offset);
175 
176 		/* Reset Borrow, Carry, Compare, and Sign flags */
177 		outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_FLAGS, base_offset + 1);
178 		/* Reset Error flag */
179 		outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_E, base_offset + 1);
180 
181 		mutex_unlock(&priv->lock);
182 
183 		return 0;
184 	case IIO_CHAN_INFO_ENABLE:
185 		/* only boolean values accepted */
186 		if (val < 0 || val > 1)
187 			return -EINVAL;
188 
189 		mutex_lock(&priv->lock);
190 
191 		priv->ab_enable[chan->channel] = val;
192 
193 		ior_cfg = val | priv->preset_enable[chan->channel] << 1;
194 
195 		/* Load I/O control configuration */
196 		outb(QUAD8_CTR_IOR | ior_cfg, base_offset + 1);
197 
198 		mutex_unlock(&priv->lock);
199 
200 		return 0;
201 	case IIO_CHAN_INFO_SCALE:
202 		mutex_lock(&priv->lock);
203 
204 		/* Quadrature scaling only available in quadrature mode */
205 		if (!priv->quadrature_mode[chan->channel] &&
206 				(val2 || val != 1)) {
207 			mutex_unlock(&priv->lock);
208 			return -EINVAL;
209 		}
210 
211 		/* Only three gain states (1, 0.5, 0.25) */
212 		if (val == 1 && !val2)
213 			priv->quadrature_scale[chan->channel] = 0;
214 		else if (!val)
215 			switch (val2) {
216 			case 500000:
217 				priv->quadrature_scale[chan->channel] = 1;
218 				break;
219 			case 250000:
220 				priv->quadrature_scale[chan->channel] = 2;
221 				break;
222 			default:
223 				mutex_unlock(&priv->lock);
224 				return -EINVAL;
225 			}
226 		else {
227 			mutex_unlock(&priv->lock);
228 			return -EINVAL;
229 		}
230 
231 		mutex_unlock(&priv->lock);
232 		return 0;
233 	}
234 
235 	return -EINVAL;
236 }
237 
238 static const struct iio_info quad8_info = {
239 	.read_raw = quad8_read_raw,
240 	.write_raw = quad8_write_raw
241 };
242 
quad8_read_preset(struct iio_dev * indio_dev,uintptr_t private,const struct iio_chan_spec * chan,char * buf)243 static ssize_t quad8_read_preset(struct iio_dev *indio_dev, uintptr_t private,
244 	const struct iio_chan_spec *chan, char *buf)
245 {
246 	const struct quad8_iio *const priv = iio_priv(indio_dev);
247 
248 	return snprintf(buf, PAGE_SIZE, "%u\n", priv->preset[chan->channel]);
249 }
250 
quad8_write_preset(struct iio_dev * indio_dev,uintptr_t private,const struct iio_chan_spec * chan,const char * buf,size_t len)251 static ssize_t quad8_write_preset(struct iio_dev *indio_dev, uintptr_t private,
252 	const struct iio_chan_spec *chan, const char *buf, size_t len)
253 {
254 	struct quad8_iio *const priv = iio_priv(indio_dev);
255 	const int base_offset = priv->base + 2 * chan->channel;
256 	unsigned int preset;
257 	int ret;
258 	int i;
259 
260 	ret = kstrtouint(buf, 0, &preset);
261 	if (ret)
262 		return ret;
263 
264 	/* Only 24-bit values are supported */
265 	if (preset > 0xFFFFFF)
266 		return -EINVAL;
267 
268 	mutex_lock(&priv->lock);
269 
270 	priv->preset[chan->channel] = preset;
271 
272 	/* Reset Byte Pointer */
273 	outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP, base_offset + 1);
274 
275 	/* Set Preset Register */
276 	for (i = 0; i < 3; i++)
277 		outb(preset >> (8 * i), base_offset);
278 
279 	mutex_unlock(&priv->lock);
280 
281 	return len;
282 }
283 
quad8_read_set_to_preset_on_index(struct iio_dev * indio_dev,uintptr_t private,const struct iio_chan_spec * chan,char * buf)284 static ssize_t quad8_read_set_to_preset_on_index(struct iio_dev *indio_dev,
285 	uintptr_t private, const struct iio_chan_spec *chan, char *buf)
286 {
287 	const struct quad8_iio *const priv = iio_priv(indio_dev);
288 
289 	return snprintf(buf, PAGE_SIZE, "%u\n",
290 		!priv->preset_enable[chan->channel]);
291 }
292 
quad8_write_set_to_preset_on_index(struct iio_dev * indio_dev,uintptr_t private,const struct iio_chan_spec * chan,const char * buf,size_t len)293 static ssize_t quad8_write_set_to_preset_on_index(struct iio_dev *indio_dev,
294 	uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
295 	size_t len)
296 {
297 	struct quad8_iio *const priv = iio_priv(indio_dev);
298 	const int base_offset = priv->base + 2 * chan->channel + 1;
299 	bool preset_enable;
300 	int ret;
301 	unsigned int ior_cfg;
302 
303 	ret = kstrtobool(buf, &preset_enable);
304 	if (ret)
305 		return ret;
306 
307 	/* Preset enable is active low in Input/Output Control register */
308 	preset_enable = !preset_enable;
309 
310 	mutex_lock(&priv->lock);
311 
312 	priv->preset_enable[chan->channel] = preset_enable;
313 
314 	ior_cfg = priv->ab_enable[chan->channel] |
315 		(unsigned int)preset_enable << 1;
316 
317 	/* Load I/O control configuration to Input / Output Control Register */
318 	outb(QUAD8_CTR_IOR | ior_cfg, base_offset);
319 
320 	mutex_unlock(&priv->lock);
321 
322 	return len;
323 }
324 
325 static const char *const quad8_noise_error_states[] = {
326 	"No excessive noise is present at the count inputs",
327 	"Excessive noise is present at the count inputs"
328 };
329 
quad8_get_noise_error(struct iio_dev * indio_dev,const struct iio_chan_spec * chan)330 static int quad8_get_noise_error(struct iio_dev *indio_dev,
331 	const struct iio_chan_spec *chan)
332 {
333 	struct quad8_iio *const priv = iio_priv(indio_dev);
334 	const int base_offset = priv->base + 2 * chan->channel + 1;
335 
336 	return !!(inb(base_offset) & QUAD8_FLAG_E);
337 }
338 
339 static const struct iio_enum quad8_noise_error_enum = {
340 	.items = quad8_noise_error_states,
341 	.num_items = ARRAY_SIZE(quad8_noise_error_states),
342 	.get = quad8_get_noise_error
343 };
344 
345 static const char *const quad8_count_direction_states[] = {
346 	"down",
347 	"up"
348 };
349 
quad8_get_count_direction(struct iio_dev * indio_dev,const struct iio_chan_spec * chan)350 static int quad8_get_count_direction(struct iio_dev *indio_dev,
351 	const struct iio_chan_spec *chan)
352 {
353 	struct quad8_iio *const priv = iio_priv(indio_dev);
354 	const int base_offset = priv->base + 2 * chan->channel + 1;
355 
356 	return !!(inb(base_offset) & QUAD8_FLAG_UD);
357 }
358 
359 static const struct iio_enum quad8_count_direction_enum = {
360 	.items = quad8_count_direction_states,
361 	.num_items = ARRAY_SIZE(quad8_count_direction_states),
362 	.get = quad8_get_count_direction
363 };
364 
365 static const char *const quad8_count_modes[] = {
366 	"normal",
367 	"range limit",
368 	"non-recycle",
369 	"modulo-n"
370 };
371 
quad8_set_count_mode(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,unsigned int cnt_mode)372 static int quad8_set_count_mode(struct iio_dev *indio_dev,
373 	const struct iio_chan_spec *chan, unsigned int cnt_mode)
374 {
375 	struct quad8_iio *const priv = iio_priv(indio_dev);
376 	unsigned int mode_cfg = cnt_mode << 1;
377 	const int base_offset = priv->base + 2 * chan->channel + 1;
378 
379 	mutex_lock(&priv->lock);
380 
381 	priv->count_mode[chan->channel] = cnt_mode;
382 
383 	/* Add quadrature mode configuration */
384 	if (priv->quadrature_mode[chan->channel])
385 		mode_cfg |= (priv->quadrature_scale[chan->channel] + 1) << 3;
386 
387 	/* Load mode configuration to Counter Mode Register */
388 	outb(QUAD8_CTR_CMR | mode_cfg, base_offset);
389 
390 	mutex_unlock(&priv->lock);
391 
392 	return 0;
393 }
394 
quad8_get_count_mode(struct iio_dev * indio_dev,const struct iio_chan_spec * chan)395 static int quad8_get_count_mode(struct iio_dev *indio_dev,
396 	const struct iio_chan_spec *chan)
397 {
398 	const struct quad8_iio *const priv = iio_priv(indio_dev);
399 
400 	return priv->count_mode[chan->channel];
401 }
402 
403 static const struct iio_enum quad8_count_mode_enum = {
404 	.items = quad8_count_modes,
405 	.num_items = ARRAY_SIZE(quad8_count_modes),
406 	.set = quad8_set_count_mode,
407 	.get = quad8_get_count_mode
408 };
409 
410 static const char *const quad8_synchronous_modes[] = {
411 	"non-synchronous",
412 	"synchronous"
413 };
414 
quad8_set_synchronous_mode(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,unsigned int synchronous_mode)415 static int quad8_set_synchronous_mode(struct iio_dev *indio_dev,
416 	const struct iio_chan_spec *chan, unsigned int synchronous_mode)
417 {
418 	struct quad8_iio *const priv = iio_priv(indio_dev);
419 	const int base_offset = priv->base + 2 * chan->channel + 1;
420 	unsigned int idr_cfg = synchronous_mode;
421 
422 	mutex_lock(&priv->lock);
423 
424 	idr_cfg |= priv->index_polarity[chan->channel] << 1;
425 
426 	/* Index function must be non-synchronous in non-quadrature mode */
427 	if (synchronous_mode && !priv->quadrature_mode[chan->channel]) {
428 		mutex_unlock(&priv->lock);
429 		return -EINVAL;
430 	}
431 
432 	priv->synchronous_mode[chan->channel] = synchronous_mode;
433 
434 	/* Load Index Control configuration to Index Control Register */
435 	outb(QUAD8_CTR_IDR | idr_cfg, base_offset);
436 
437 	mutex_unlock(&priv->lock);
438 
439 	return 0;
440 }
441 
quad8_get_synchronous_mode(struct iio_dev * indio_dev,const struct iio_chan_spec * chan)442 static int quad8_get_synchronous_mode(struct iio_dev *indio_dev,
443 	const struct iio_chan_spec *chan)
444 {
445 	const struct quad8_iio *const priv = iio_priv(indio_dev);
446 
447 	return priv->synchronous_mode[chan->channel];
448 }
449 
450 static const struct iio_enum quad8_synchronous_mode_enum = {
451 	.items = quad8_synchronous_modes,
452 	.num_items = ARRAY_SIZE(quad8_synchronous_modes),
453 	.set = quad8_set_synchronous_mode,
454 	.get = quad8_get_synchronous_mode
455 };
456 
457 static const char *const quad8_quadrature_modes[] = {
458 	"non-quadrature",
459 	"quadrature"
460 };
461 
quad8_set_quadrature_mode(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,unsigned int quadrature_mode)462 static int quad8_set_quadrature_mode(struct iio_dev *indio_dev,
463 	const struct iio_chan_spec *chan, unsigned int quadrature_mode)
464 {
465 	struct quad8_iio *const priv = iio_priv(indio_dev);
466 	const int base_offset = priv->base + 2 * chan->channel + 1;
467 	unsigned int mode_cfg;
468 
469 	mutex_lock(&priv->lock);
470 
471 	mode_cfg = priv->count_mode[chan->channel] << 1;
472 
473 	if (quadrature_mode)
474 		mode_cfg |= (priv->quadrature_scale[chan->channel] + 1) << 3;
475 	else {
476 		/* Quadrature scaling only available in quadrature mode */
477 		priv->quadrature_scale[chan->channel] = 0;
478 
479 		/* Synchronous function not supported in non-quadrature mode */
480 		if (priv->synchronous_mode[chan->channel])
481 			quad8_set_synchronous_mode(indio_dev, chan, 0);
482 	}
483 
484 	priv->quadrature_mode[chan->channel] = quadrature_mode;
485 
486 	/* Load mode configuration to Counter Mode Register */
487 	outb(QUAD8_CTR_CMR | mode_cfg, base_offset);
488 
489 	mutex_unlock(&priv->lock);
490 
491 	return 0;
492 }
493 
quad8_get_quadrature_mode(struct iio_dev * indio_dev,const struct iio_chan_spec * chan)494 static int quad8_get_quadrature_mode(struct iio_dev *indio_dev,
495 	const struct iio_chan_spec *chan)
496 {
497 	const struct quad8_iio *const priv = iio_priv(indio_dev);
498 
499 	return priv->quadrature_mode[chan->channel];
500 }
501 
502 static const struct iio_enum quad8_quadrature_mode_enum = {
503 	.items = quad8_quadrature_modes,
504 	.num_items = ARRAY_SIZE(quad8_quadrature_modes),
505 	.set = quad8_set_quadrature_mode,
506 	.get = quad8_get_quadrature_mode
507 };
508 
509 static const char *const quad8_index_polarity_modes[] = {
510 	"negative",
511 	"positive"
512 };
513 
quad8_set_index_polarity(struct iio_dev * indio_dev,const struct iio_chan_spec * chan,unsigned int index_polarity)514 static int quad8_set_index_polarity(struct iio_dev *indio_dev,
515 	const struct iio_chan_spec *chan, unsigned int index_polarity)
516 {
517 	struct quad8_iio *const priv = iio_priv(indio_dev);
518 	const int base_offset = priv->base + 2 * chan->channel + 1;
519 	unsigned int idr_cfg = index_polarity << 1;
520 
521 	mutex_lock(&priv->lock);
522 
523 	idr_cfg |= priv->synchronous_mode[chan->channel];
524 
525 	priv->index_polarity[chan->channel] = index_polarity;
526 
527 	/* Load Index Control configuration to Index Control Register */
528 	outb(QUAD8_CTR_IDR | idr_cfg, base_offset);
529 
530 	mutex_unlock(&priv->lock);
531 
532 	return 0;
533 }
534 
quad8_get_index_polarity(struct iio_dev * indio_dev,const struct iio_chan_spec * chan)535 static int quad8_get_index_polarity(struct iio_dev *indio_dev,
536 	const struct iio_chan_spec *chan)
537 {
538 	const struct quad8_iio *const priv = iio_priv(indio_dev);
539 
540 	return priv->index_polarity[chan->channel];
541 }
542 
543 static const struct iio_enum quad8_index_polarity_enum = {
544 	.items = quad8_index_polarity_modes,
545 	.num_items = ARRAY_SIZE(quad8_index_polarity_modes),
546 	.set = quad8_set_index_polarity,
547 	.get = quad8_get_index_polarity
548 };
549 
550 static const struct iio_chan_spec_ext_info quad8_count_ext_info[] = {
551 	{
552 		.name = "preset",
553 		.shared = IIO_SEPARATE,
554 		.read = quad8_read_preset,
555 		.write = quad8_write_preset
556 	},
557 	{
558 		.name = "set_to_preset_on_index",
559 		.shared = IIO_SEPARATE,
560 		.read = quad8_read_set_to_preset_on_index,
561 		.write = quad8_write_set_to_preset_on_index
562 	},
563 	IIO_ENUM("noise_error", IIO_SEPARATE, &quad8_noise_error_enum),
564 	IIO_ENUM_AVAILABLE("noise_error", &quad8_noise_error_enum),
565 	IIO_ENUM("count_direction", IIO_SEPARATE, &quad8_count_direction_enum),
566 	IIO_ENUM_AVAILABLE("count_direction", &quad8_count_direction_enum),
567 	IIO_ENUM("count_mode", IIO_SEPARATE, &quad8_count_mode_enum),
568 	IIO_ENUM_AVAILABLE("count_mode", &quad8_count_mode_enum),
569 	IIO_ENUM("quadrature_mode", IIO_SEPARATE, &quad8_quadrature_mode_enum),
570 	IIO_ENUM_AVAILABLE("quadrature_mode", &quad8_quadrature_mode_enum),
571 	{}
572 };
573 
574 static const struct iio_chan_spec_ext_info quad8_index_ext_info[] = {
575 	IIO_ENUM("synchronous_mode", IIO_SEPARATE,
576 		&quad8_synchronous_mode_enum),
577 	IIO_ENUM_AVAILABLE("synchronous_mode", &quad8_synchronous_mode_enum),
578 	IIO_ENUM("index_polarity", IIO_SEPARATE, &quad8_index_polarity_enum),
579 	IIO_ENUM_AVAILABLE("index_polarity", &quad8_index_polarity_enum),
580 	{}
581 };
582 
583 #define QUAD8_COUNT_CHAN(_chan) {					\
584 	.type = IIO_COUNT,						\
585 	.channel = (_chan),						\
586 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |			\
587 		BIT(IIO_CHAN_INFO_ENABLE) | BIT(IIO_CHAN_INFO_SCALE),	\
588 	.ext_info = quad8_count_ext_info,				\
589 	.indexed = 1							\
590 }
591 
592 #define QUAD8_INDEX_CHAN(_chan) {			\
593 	.type = IIO_INDEX,				\
594 	.channel = (_chan),				\
595 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	\
596 	.ext_info = quad8_index_ext_info,		\
597 	.indexed = 1					\
598 }
599 
600 static const struct iio_chan_spec quad8_channels[] = {
601 	QUAD8_COUNT_CHAN(0), QUAD8_INDEX_CHAN(0),
602 	QUAD8_COUNT_CHAN(1), QUAD8_INDEX_CHAN(1),
603 	QUAD8_COUNT_CHAN(2), QUAD8_INDEX_CHAN(2),
604 	QUAD8_COUNT_CHAN(3), QUAD8_INDEX_CHAN(3),
605 	QUAD8_COUNT_CHAN(4), QUAD8_INDEX_CHAN(4),
606 	QUAD8_COUNT_CHAN(5), QUAD8_INDEX_CHAN(5),
607 	QUAD8_COUNT_CHAN(6), QUAD8_INDEX_CHAN(6),
608 	QUAD8_COUNT_CHAN(7), QUAD8_INDEX_CHAN(7)
609 };
610 
quad8_signal_read(struct counter_device * counter,struct counter_signal * signal,enum counter_signal_value * val)611 static int quad8_signal_read(struct counter_device *counter,
612 	struct counter_signal *signal, enum counter_signal_value *val)
613 {
614 	const struct quad8_iio *const priv = counter->priv;
615 	unsigned int state;
616 
617 	/* Only Index signal levels can be read */
618 	if (signal->id < 16)
619 		return -EINVAL;
620 
621 	state = inb(priv->base + QUAD8_REG_INDEX_INPUT_LEVELS)
622 		& BIT(signal->id - 16);
623 
624 	*val = (state) ? COUNTER_SIGNAL_HIGH : COUNTER_SIGNAL_LOW;
625 
626 	return 0;
627 }
628 
quad8_count_read(struct counter_device * counter,struct counter_count * count,unsigned long * val)629 static int quad8_count_read(struct counter_device *counter,
630 	struct counter_count *count, unsigned long *val)
631 {
632 	struct quad8_iio *const priv = counter->priv;
633 	const int base_offset = priv->base + 2 * count->id;
634 	int i;
635 
636 	*val = 0;
637 
638 	mutex_lock(&priv->lock);
639 
640 	/* Reset Byte Pointer; transfer Counter to Output Latch */
641 	outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP | QUAD8_RLD_CNTR_OUT,
642 	     base_offset + 1);
643 
644 	for (i = 0; i < 3; i++)
645 		*val |= (unsigned long)inb(base_offset) << (8 * i);
646 
647 	mutex_unlock(&priv->lock);
648 
649 	return 0;
650 }
651 
quad8_count_write(struct counter_device * counter,struct counter_count * count,unsigned long val)652 static int quad8_count_write(struct counter_device *counter,
653 	struct counter_count *count, unsigned long val)
654 {
655 	struct quad8_iio *const priv = counter->priv;
656 	const int base_offset = priv->base + 2 * count->id;
657 	int i;
658 
659 	/* Only 24-bit values are supported */
660 	if (val > 0xFFFFFF)
661 		return -EINVAL;
662 
663 	mutex_lock(&priv->lock);
664 
665 	/* Reset Byte Pointer */
666 	outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP, base_offset + 1);
667 
668 	/* Counter can only be set via Preset Register */
669 	for (i = 0; i < 3; i++)
670 		outb(val >> (8 * i), base_offset);
671 
672 	/* Transfer Preset Register to Counter */
673 	outb(QUAD8_CTR_RLD | QUAD8_RLD_PRESET_CNTR, base_offset + 1);
674 
675 	/* Reset Byte Pointer */
676 	outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP, base_offset + 1);
677 
678 	/* Set Preset Register back to original value */
679 	val = priv->preset[count->id];
680 	for (i = 0; i < 3; i++)
681 		outb(val >> (8 * i), base_offset);
682 
683 	/* Reset Borrow, Carry, Compare, and Sign flags */
684 	outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_FLAGS, base_offset + 1);
685 	/* Reset Error flag */
686 	outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_E, base_offset + 1);
687 
688 	mutex_unlock(&priv->lock);
689 
690 	return 0;
691 }
692 
693 enum quad8_count_function {
694 	QUAD8_COUNT_FUNCTION_PULSE_DIRECTION = 0,
695 	QUAD8_COUNT_FUNCTION_QUADRATURE_X1,
696 	QUAD8_COUNT_FUNCTION_QUADRATURE_X2,
697 	QUAD8_COUNT_FUNCTION_QUADRATURE_X4
698 };
699 
700 static enum counter_count_function quad8_count_functions_list[] = {
701 	[QUAD8_COUNT_FUNCTION_PULSE_DIRECTION] = COUNTER_COUNT_FUNCTION_PULSE_DIRECTION,
702 	[QUAD8_COUNT_FUNCTION_QUADRATURE_X1] = COUNTER_COUNT_FUNCTION_QUADRATURE_X1_A,
703 	[QUAD8_COUNT_FUNCTION_QUADRATURE_X2] = COUNTER_COUNT_FUNCTION_QUADRATURE_X2_A,
704 	[QUAD8_COUNT_FUNCTION_QUADRATURE_X4] = COUNTER_COUNT_FUNCTION_QUADRATURE_X4
705 };
706 
quad8_function_get(struct counter_device * counter,struct counter_count * count,size_t * function)707 static int quad8_function_get(struct counter_device *counter,
708 	struct counter_count *count, size_t *function)
709 {
710 	struct quad8_iio *const priv = counter->priv;
711 	const int id = count->id;
712 
713 	mutex_lock(&priv->lock);
714 
715 	if (priv->quadrature_mode[id])
716 		switch (priv->quadrature_scale[id]) {
717 		case 0:
718 			*function = QUAD8_COUNT_FUNCTION_QUADRATURE_X1;
719 			break;
720 		case 1:
721 			*function = QUAD8_COUNT_FUNCTION_QUADRATURE_X2;
722 			break;
723 		case 2:
724 			*function = QUAD8_COUNT_FUNCTION_QUADRATURE_X4;
725 			break;
726 		}
727 	else
728 		*function = QUAD8_COUNT_FUNCTION_PULSE_DIRECTION;
729 
730 	mutex_unlock(&priv->lock);
731 
732 	return 0;
733 }
734 
quad8_function_set(struct counter_device * counter,struct counter_count * count,size_t function)735 static int quad8_function_set(struct counter_device *counter,
736 	struct counter_count *count, size_t function)
737 {
738 	struct quad8_iio *const priv = counter->priv;
739 	const int id = count->id;
740 	unsigned int *const quadrature_mode = priv->quadrature_mode + id;
741 	unsigned int *const scale = priv->quadrature_scale + id;
742 	unsigned int *const synchronous_mode = priv->synchronous_mode + id;
743 	const int base_offset = priv->base + 2 * id + 1;
744 	unsigned int mode_cfg;
745 	unsigned int idr_cfg;
746 
747 	mutex_lock(&priv->lock);
748 
749 	mode_cfg = priv->count_mode[id] << 1;
750 	idr_cfg = priv->index_polarity[id] << 1;
751 
752 	if (function == QUAD8_COUNT_FUNCTION_PULSE_DIRECTION) {
753 		*quadrature_mode = 0;
754 
755 		/* Quadrature scaling only available in quadrature mode */
756 		*scale = 0;
757 
758 		/* Synchronous function not supported in non-quadrature mode */
759 		if (*synchronous_mode) {
760 			*synchronous_mode = 0;
761 			/* Disable synchronous function mode */
762 			outb(QUAD8_CTR_IDR | idr_cfg, base_offset);
763 		}
764 	} else {
765 		*quadrature_mode = 1;
766 
767 		switch (function) {
768 		case QUAD8_COUNT_FUNCTION_QUADRATURE_X1:
769 			*scale = 0;
770 			mode_cfg |= QUAD8_CMR_QUADRATURE_X1;
771 			break;
772 		case QUAD8_COUNT_FUNCTION_QUADRATURE_X2:
773 			*scale = 1;
774 			mode_cfg |= QUAD8_CMR_QUADRATURE_X2;
775 			break;
776 		case QUAD8_COUNT_FUNCTION_QUADRATURE_X4:
777 			*scale = 2;
778 			mode_cfg |= QUAD8_CMR_QUADRATURE_X4;
779 			break;
780 		}
781 	}
782 
783 	/* Load mode configuration to Counter Mode Register */
784 	outb(QUAD8_CTR_CMR | mode_cfg, base_offset);
785 
786 	mutex_unlock(&priv->lock);
787 
788 	return 0;
789 }
790 
quad8_direction_get(struct counter_device * counter,struct counter_count * count,enum counter_count_direction * direction)791 static void quad8_direction_get(struct counter_device *counter,
792 	struct counter_count *count, enum counter_count_direction *direction)
793 {
794 	const struct quad8_iio *const priv = counter->priv;
795 	unsigned int ud_flag;
796 	const unsigned int flag_addr = priv->base + 2 * count->id + 1;
797 
798 	/* U/D flag: nonzero = up, zero = down */
799 	ud_flag = inb(flag_addr) & QUAD8_FLAG_UD;
800 
801 	*direction = (ud_flag) ? COUNTER_COUNT_DIRECTION_FORWARD :
802 		COUNTER_COUNT_DIRECTION_BACKWARD;
803 }
804 
805 enum quad8_synapse_action {
806 	QUAD8_SYNAPSE_ACTION_NONE = 0,
807 	QUAD8_SYNAPSE_ACTION_RISING_EDGE,
808 	QUAD8_SYNAPSE_ACTION_FALLING_EDGE,
809 	QUAD8_SYNAPSE_ACTION_BOTH_EDGES
810 };
811 
812 static enum counter_synapse_action quad8_index_actions_list[] = {
813 	[QUAD8_SYNAPSE_ACTION_NONE] = COUNTER_SYNAPSE_ACTION_NONE,
814 	[QUAD8_SYNAPSE_ACTION_RISING_EDGE] = COUNTER_SYNAPSE_ACTION_RISING_EDGE
815 };
816 
817 static enum counter_synapse_action quad8_synapse_actions_list[] = {
818 	[QUAD8_SYNAPSE_ACTION_NONE] = COUNTER_SYNAPSE_ACTION_NONE,
819 	[QUAD8_SYNAPSE_ACTION_RISING_EDGE] = COUNTER_SYNAPSE_ACTION_RISING_EDGE,
820 	[QUAD8_SYNAPSE_ACTION_FALLING_EDGE] = COUNTER_SYNAPSE_ACTION_FALLING_EDGE,
821 	[QUAD8_SYNAPSE_ACTION_BOTH_EDGES] = COUNTER_SYNAPSE_ACTION_BOTH_EDGES
822 };
823 
quad8_action_get(struct counter_device * counter,struct counter_count * count,struct counter_synapse * synapse,size_t * action)824 static int quad8_action_get(struct counter_device *counter,
825 	struct counter_count *count, struct counter_synapse *synapse,
826 	size_t *action)
827 {
828 	struct quad8_iio *const priv = counter->priv;
829 	int err;
830 	size_t function = 0;
831 	const size_t signal_a_id = count->synapses[0].signal->id;
832 	enum counter_count_direction direction;
833 
834 	/* Handle Index signals */
835 	if (synapse->signal->id >= 16) {
836 		if (priv->preset_enable[count->id])
837 			*action = QUAD8_SYNAPSE_ACTION_RISING_EDGE;
838 		else
839 			*action = QUAD8_SYNAPSE_ACTION_NONE;
840 
841 		return 0;
842 	}
843 
844 	err = quad8_function_get(counter, count, &function);
845 	if (err)
846 		return err;
847 
848 	/* Default action mode */
849 	*action = QUAD8_SYNAPSE_ACTION_NONE;
850 
851 	/* Determine action mode based on current count function mode */
852 	switch (function) {
853 	case QUAD8_COUNT_FUNCTION_PULSE_DIRECTION:
854 		if (synapse->signal->id == signal_a_id)
855 			*action = QUAD8_SYNAPSE_ACTION_RISING_EDGE;
856 		break;
857 	case QUAD8_COUNT_FUNCTION_QUADRATURE_X1:
858 		if (synapse->signal->id == signal_a_id) {
859 			quad8_direction_get(counter, count, &direction);
860 
861 			if (direction == COUNTER_COUNT_DIRECTION_FORWARD)
862 				*action = QUAD8_SYNAPSE_ACTION_RISING_EDGE;
863 			else
864 				*action = QUAD8_SYNAPSE_ACTION_FALLING_EDGE;
865 		}
866 		break;
867 	case QUAD8_COUNT_FUNCTION_QUADRATURE_X2:
868 		if (synapse->signal->id == signal_a_id)
869 			*action = QUAD8_SYNAPSE_ACTION_BOTH_EDGES;
870 		break;
871 	case QUAD8_COUNT_FUNCTION_QUADRATURE_X4:
872 		*action = QUAD8_SYNAPSE_ACTION_BOTH_EDGES;
873 		break;
874 	}
875 
876 	return 0;
877 }
878 
879 static const struct counter_ops quad8_ops = {
880 	.signal_read = quad8_signal_read,
881 	.count_read = quad8_count_read,
882 	.count_write = quad8_count_write,
883 	.function_get = quad8_function_get,
884 	.function_set = quad8_function_set,
885 	.action_get = quad8_action_get
886 };
887 
quad8_index_polarity_get(struct counter_device * counter,struct counter_signal * signal,size_t * index_polarity)888 static int quad8_index_polarity_get(struct counter_device *counter,
889 	struct counter_signal *signal, size_t *index_polarity)
890 {
891 	const struct quad8_iio *const priv = counter->priv;
892 	const size_t channel_id = signal->id - 16;
893 
894 	*index_polarity = priv->index_polarity[channel_id];
895 
896 	return 0;
897 }
898 
quad8_index_polarity_set(struct counter_device * counter,struct counter_signal * signal,size_t index_polarity)899 static int quad8_index_polarity_set(struct counter_device *counter,
900 	struct counter_signal *signal, size_t index_polarity)
901 {
902 	struct quad8_iio *const priv = counter->priv;
903 	const size_t channel_id = signal->id - 16;
904 	const int base_offset = priv->base + 2 * channel_id + 1;
905 	unsigned int idr_cfg = index_polarity << 1;
906 
907 	mutex_lock(&priv->lock);
908 
909 	idr_cfg |= priv->synchronous_mode[channel_id];
910 
911 	priv->index_polarity[channel_id] = index_polarity;
912 
913 	/* Load Index Control configuration to Index Control Register */
914 	outb(QUAD8_CTR_IDR | idr_cfg, base_offset);
915 
916 	mutex_unlock(&priv->lock);
917 
918 	return 0;
919 }
920 
921 static struct counter_signal_enum_ext quad8_index_pol_enum = {
922 	.items = quad8_index_polarity_modes,
923 	.num_items = ARRAY_SIZE(quad8_index_polarity_modes),
924 	.get = quad8_index_polarity_get,
925 	.set = quad8_index_polarity_set
926 };
927 
quad8_synchronous_mode_get(struct counter_device * counter,struct counter_signal * signal,size_t * synchronous_mode)928 static int quad8_synchronous_mode_get(struct counter_device *counter,
929 	struct counter_signal *signal, size_t *synchronous_mode)
930 {
931 	const struct quad8_iio *const priv = counter->priv;
932 	const size_t channel_id = signal->id - 16;
933 
934 	*synchronous_mode = priv->synchronous_mode[channel_id];
935 
936 	return 0;
937 }
938 
quad8_synchronous_mode_set(struct counter_device * counter,struct counter_signal * signal,size_t synchronous_mode)939 static int quad8_synchronous_mode_set(struct counter_device *counter,
940 	struct counter_signal *signal, size_t synchronous_mode)
941 {
942 	struct quad8_iio *const priv = counter->priv;
943 	const size_t channel_id = signal->id - 16;
944 	const int base_offset = priv->base + 2 * channel_id + 1;
945 	unsigned int idr_cfg = synchronous_mode;
946 
947 	mutex_lock(&priv->lock);
948 
949 	idr_cfg |= priv->index_polarity[channel_id] << 1;
950 
951 	/* Index function must be non-synchronous in non-quadrature mode */
952 	if (synchronous_mode && !priv->quadrature_mode[channel_id]) {
953 		mutex_unlock(&priv->lock);
954 		return -EINVAL;
955 	}
956 
957 	priv->synchronous_mode[channel_id] = synchronous_mode;
958 
959 	/* Load Index Control configuration to Index Control Register */
960 	outb(QUAD8_CTR_IDR | idr_cfg, base_offset);
961 
962 	mutex_unlock(&priv->lock);
963 
964 	return 0;
965 }
966 
967 static struct counter_signal_enum_ext quad8_syn_mode_enum = {
968 	.items = quad8_synchronous_modes,
969 	.num_items = ARRAY_SIZE(quad8_synchronous_modes),
970 	.get = quad8_synchronous_mode_get,
971 	.set = quad8_synchronous_mode_set
972 };
973 
quad8_count_floor_read(struct counter_device * counter,struct counter_count * count,void * private,char * buf)974 static ssize_t quad8_count_floor_read(struct counter_device *counter,
975 	struct counter_count *count, void *private, char *buf)
976 {
977 	/* Only a floor of 0 is supported */
978 	return sprintf(buf, "0\n");
979 }
980 
quad8_count_mode_get(struct counter_device * counter,struct counter_count * count,size_t * cnt_mode)981 static int quad8_count_mode_get(struct counter_device *counter,
982 	struct counter_count *count, size_t *cnt_mode)
983 {
984 	const struct quad8_iio *const priv = counter->priv;
985 
986 	/* Map 104-QUAD-8 count mode to Generic Counter count mode */
987 	switch (priv->count_mode[count->id]) {
988 	case 0:
989 		*cnt_mode = COUNTER_COUNT_MODE_NORMAL;
990 		break;
991 	case 1:
992 		*cnt_mode = COUNTER_COUNT_MODE_RANGE_LIMIT;
993 		break;
994 	case 2:
995 		*cnt_mode = COUNTER_COUNT_MODE_NON_RECYCLE;
996 		break;
997 	case 3:
998 		*cnt_mode = COUNTER_COUNT_MODE_MODULO_N;
999 		break;
1000 	}
1001 
1002 	return 0;
1003 }
1004 
quad8_count_mode_set(struct counter_device * counter,struct counter_count * count,size_t cnt_mode)1005 static int quad8_count_mode_set(struct counter_device *counter,
1006 	struct counter_count *count, size_t cnt_mode)
1007 {
1008 	struct quad8_iio *const priv = counter->priv;
1009 	unsigned int mode_cfg;
1010 	const int base_offset = priv->base + 2 * count->id + 1;
1011 
1012 	/* Map Generic Counter count mode to 104-QUAD-8 count mode */
1013 	switch (cnt_mode) {
1014 	case COUNTER_COUNT_MODE_NORMAL:
1015 		cnt_mode = 0;
1016 		break;
1017 	case COUNTER_COUNT_MODE_RANGE_LIMIT:
1018 		cnt_mode = 1;
1019 		break;
1020 	case COUNTER_COUNT_MODE_NON_RECYCLE:
1021 		cnt_mode = 2;
1022 		break;
1023 	case COUNTER_COUNT_MODE_MODULO_N:
1024 		cnt_mode = 3;
1025 		break;
1026 	}
1027 
1028 	mutex_lock(&priv->lock);
1029 
1030 	priv->count_mode[count->id] = cnt_mode;
1031 
1032 	/* Set count mode configuration value */
1033 	mode_cfg = cnt_mode << 1;
1034 
1035 	/* Add quadrature mode configuration */
1036 	if (priv->quadrature_mode[count->id])
1037 		mode_cfg |= (priv->quadrature_scale[count->id] + 1) << 3;
1038 
1039 	/* Load mode configuration to Counter Mode Register */
1040 	outb(QUAD8_CTR_CMR | mode_cfg, base_offset);
1041 
1042 	mutex_unlock(&priv->lock);
1043 
1044 	return 0;
1045 }
1046 
1047 static struct counter_count_enum_ext quad8_cnt_mode_enum = {
1048 	.items = counter_count_mode_str,
1049 	.num_items = ARRAY_SIZE(counter_count_mode_str),
1050 	.get = quad8_count_mode_get,
1051 	.set = quad8_count_mode_set
1052 };
1053 
quad8_count_direction_read(struct counter_device * counter,struct counter_count * count,void * priv,char * buf)1054 static ssize_t quad8_count_direction_read(struct counter_device *counter,
1055 	struct counter_count *count, void *priv, char *buf)
1056 {
1057 	enum counter_count_direction dir;
1058 
1059 	quad8_direction_get(counter, count, &dir);
1060 
1061 	return sprintf(buf, "%s\n", counter_count_direction_str[dir]);
1062 }
1063 
quad8_count_enable_read(struct counter_device * counter,struct counter_count * count,void * private,char * buf)1064 static ssize_t quad8_count_enable_read(struct counter_device *counter,
1065 	struct counter_count *count, void *private, char *buf)
1066 {
1067 	const struct quad8_iio *const priv = counter->priv;
1068 
1069 	return sprintf(buf, "%u\n", priv->ab_enable[count->id]);
1070 }
1071 
quad8_count_enable_write(struct counter_device * counter,struct counter_count * count,void * private,const char * buf,size_t len)1072 static ssize_t quad8_count_enable_write(struct counter_device *counter,
1073 	struct counter_count *count, void *private, const char *buf, size_t len)
1074 {
1075 	struct quad8_iio *const priv = counter->priv;
1076 	const int base_offset = priv->base + 2 * count->id;
1077 	int err;
1078 	bool ab_enable;
1079 	unsigned int ior_cfg;
1080 
1081 	err = kstrtobool(buf, &ab_enable);
1082 	if (err)
1083 		return err;
1084 
1085 	mutex_lock(&priv->lock);
1086 
1087 	priv->ab_enable[count->id] = ab_enable;
1088 
1089 	ior_cfg = ab_enable | priv->preset_enable[count->id] << 1;
1090 
1091 	/* Load I/O control configuration */
1092 	outb(QUAD8_CTR_IOR | ior_cfg, base_offset + 1);
1093 
1094 	mutex_unlock(&priv->lock);
1095 
1096 	return len;
1097 }
1098 
quad8_error_noise_get(struct counter_device * counter,struct counter_count * count,size_t * noise_error)1099 static int quad8_error_noise_get(struct counter_device *counter,
1100 	struct counter_count *count, size_t *noise_error)
1101 {
1102 	const struct quad8_iio *const priv = counter->priv;
1103 	const int base_offset = priv->base + 2 * count->id + 1;
1104 
1105 	*noise_error = !!(inb(base_offset) & QUAD8_FLAG_E);
1106 
1107 	return 0;
1108 }
1109 
1110 static struct counter_count_enum_ext quad8_error_noise_enum = {
1111 	.items = quad8_noise_error_states,
1112 	.num_items = ARRAY_SIZE(quad8_noise_error_states),
1113 	.get = quad8_error_noise_get
1114 };
1115 
quad8_count_preset_read(struct counter_device * counter,struct counter_count * count,void * private,char * buf)1116 static ssize_t quad8_count_preset_read(struct counter_device *counter,
1117 	struct counter_count *count, void *private, char *buf)
1118 {
1119 	const struct quad8_iio *const priv = counter->priv;
1120 
1121 	return sprintf(buf, "%u\n", priv->preset[count->id]);
1122 }
1123 
quad8_preset_register_set(struct quad8_iio * quad8iio,int id,unsigned int preset)1124 static void quad8_preset_register_set(struct quad8_iio *quad8iio, int id,
1125 		unsigned int preset)
1126 {
1127 	const unsigned int base_offset = quad8iio->base + 2 * id;
1128 	int i;
1129 
1130 	quad8iio->preset[id] = preset;
1131 
1132 	/* Reset Byte Pointer */
1133 	outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP, base_offset + 1);
1134 
1135 	/* Set Preset Register */
1136 	for (i = 0; i < 3; i++)
1137 		outb(preset >> (8 * i), base_offset);
1138 }
1139 
quad8_count_preset_write(struct counter_device * counter,struct counter_count * count,void * private,const char * buf,size_t len)1140 static ssize_t quad8_count_preset_write(struct counter_device *counter,
1141 	struct counter_count *count, void *private, const char *buf, size_t len)
1142 {
1143 	struct quad8_iio *const priv = counter->priv;
1144 	unsigned int preset;
1145 	int ret;
1146 
1147 	ret = kstrtouint(buf, 0, &preset);
1148 	if (ret)
1149 		return ret;
1150 
1151 	/* Only 24-bit values are supported */
1152 	if (preset > 0xFFFFFF)
1153 		return -EINVAL;
1154 
1155 	mutex_lock(&priv->lock);
1156 
1157 	quad8_preset_register_set(priv, count->id, preset);
1158 
1159 	mutex_unlock(&priv->lock);
1160 
1161 	return len;
1162 }
1163 
quad8_count_ceiling_read(struct counter_device * counter,struct counter_count * count,void * private,char * buf)1164 static ssize_t quad8_count_ceiling_read(struct counter_device *counter,
1165 	struct counter_count *count, void *private, char *buf)
1166 {
1167 	struct quad8_iio *const priv = counter->priv;
1168 
1169 	mutex_lock(&priv->lock);
1170 
1171 	/* Range Limit and Modulo-N count modes use preset value as ceiling */
1172 	switch (priv->count_mode[count->id]) {
1173 	case 1:
1174 	case 3:
1175 		mutex_unlock(&priv->lock);
1176 		return sprintf(buf, "%u\n", priv->preset[count->id]);
1177 	}
1178 
1179 	mutex_unlock(&priv->lock);
1180 
1181 	/* By default 0xFFFFFF (24 bits unsigned) is maximum count */
1182 	return sprintf(buf, "16777215\n");
1183 }
1184 
quad8_count_ceiling_write(struct counter_device * counter,struct counter_count * count,void * private,const char * buf,size_t len)1185 static ssize_t quad8_count_ceiling_write(struct counter_device *counter,
1186 	struct counter_count *count, void *private, const char *buf, size_t len)
1187 {
1188 	struct quad8_iio *const priv = counter->priv;
1189 	unsigned int ceiling;
1190 	int ret;
1191 
1192 	ret = kstrtouint(buf, 0, &ceiling);
1193 	if (ret)
1194 		return ret;
1195 
1196 	/* Only 24-bit values are supported */
1197 	if (ceiling > 0xFFFFFF)
1198 		return -EINVAL;
1199 
1200 	mutex_lock(&priv->lock);
1201 
1202 	/* Range Limit and Modulo-N count modes use preset value as ceiling */
1203 	switch (priv->count_mode[count->id]) {
1204 	case 1:
1205 	case 3:
1206 		quad8_preset_register_set(priv, count->id, ceiling);
1207 		mutex_unlock(&priv->lock);
1208 		return len;
1209 	}
1210 
1211 	mutex_unlock(&priv->lock);
1212 
1213 	return -EINVAL;
1214 }
1215 
quad8_count_preset_enable_read(struct counter_device * counter,struct counter_count * count,void * private,char * buf)1216 static ssize_t quad8_count_preset_enable_read(struct counter_device *counter,
1217 	struct counter_count *count, void *private, char *buf)
1218 {
1219 	const struct quad8_iio *const priv = counter->priv;
1220 
1221 	return sprintf(buf, "%u\n", !priv->preset_enable[count->id]);
1222 }
1223 
quad8_count_preset_enable_write(struct counter_device * counter,struct counter_count * count,void * private,const char * buf,size_t len)1224 static ssize_t quad8_count_preset_enable_write(struct counter_device *counter,
1225 	struct counter_count *count, void *private, const char *buf, size_t len)
1226 {
1227 	struct quad8_iio *const priv = counter->priv;
1228 	const int base_offset = priv->base + 2 * count->id + 1;
1229 	bool preset_enable;
1230 	int ret;
1231 	unsigned int ior_cfg;
1232 
1233 	ret = kstrtobool(buf, &preset_enable);
1234 	if (ret)
1235 		return ret;
1236 
1237 	/* Preset enable is active low in Input/Output Control register */
1238 	preset_enable = !preset_enable;
1239 
1240 	mutex_lock(&priv->lock);
1241 
1242 	priv->preset_enable[count->id] = preset_enable;
1243 
1244 	ior_cfg = priv->ab_enable[count->id] | (unsigned int)preset_enable << 1;
1245 
1246 	/* Load I/O control configuration to Input / Output Control Register */
1247 	outb(QUAD8_CTR_IOR | ior_cfg, base_offset);
1248 
1249 	mutex_unlock(&priv->lock);
1250 
1251 	return len;
1252 }
1253 
quad8_signal_cable_fault_read(struct counter_device * counter,struct counter_signal * signal,void * private,char * buf)1254 static ssize_t quad8_signal_cable_fault_read(struct counter_device *counter,
1255 					     struct counter_signal *signal,
1256 					     void *private, char *buf)
1257 {
1258 	struct quad8_iio *const priv = counter->priv;
1259 	const size_t channel_id = signal->id / 2;
1260 	bool disabled;
1261 	unsigned int status;
1262 	unsigned int fault;
1263 
1264 	mutex_lock(&priv->lock);
1265 
1266 	disabled = !(priv->cable_fault_enable & BIT(channel_id));
1267 
1268 	if (disabled) {
1269 		mutex_unlock(&priv->lock);
1270 		return -EINVAL;
1271 	}
1272 
1273 	/* Logic 0 = cable fault */
1274 	status = inb(priv->base + QUAD8_DIFF_ENCODER_CABLE_STATUS);
1275 
1276 	mutex_unlock(&priv->lock);
1277 
1278 	/* Mask respective channel and invert logic */
1279 	fault = !(status & BIT(channel_id));
1280 
1281 	return sprintf(buf, "%u\n", fault);
1282 }
1283 
quad8_signal_cable_fault_enable_read(struct counter_device * counter,struct counter_signal * signal,void * private,char * buf)1284 static ssize_t quad8_signal_cable_fault_enable_read(
1285 	struct counter_device *counter, struct counter_signal *signal,
1286 	void *private, char *buf)
1287 {
1288 	const struct quad8_iio *const priv = counter->priv;
1289 	const size_t channel_id = signal->id / 2;
1290 	const unsigned int enb = !!(priv->cable_fault_enable & BIT(channel_id));
1291 
1292 	return sprintf(buf, "%u\n", enb);
1293 }
1294 
quad8_signal_cable_fault_enable_write(struct counter_device * counter,struct counter_signal * signal,void * private,const char * buf,size_t len)1295 static ssize_t quad8_signal_cable_fault_enable_write(
1296 	struct counter_device *counter, struct counter_signal *signal,
1297 	void *private, const char *buf, size_t len)
1298 {
1299 	struct quad8_iio *const priv = counter->priv;
1300 	const size_t channel_id = signal->id / 2;
1301 	bool enable;
1302 	int ret;
1303 	unsigned int cable_fault_enable;
1304 
1305 	ret = kstrtobool(buf, &enable);
1306 	if (ret)
1307 		return ret;
1308 
1309 	mutex_lock(&priv->lock);
1310 
1311 	if (enable)
1312 		priv->cable_fault_enable |= BIT(channel_id);
1313 	else
1314 		priv->cable_fault_enable &= ~BIT(channel_id);
1315 
1316 	/* Enable is active low in Differential Encoder Cable Status register */
1317 	cable_fault_enable = ~priv->cable_fault_enable;
1318 
1319 	outb(cable_fault_enable, priv->base + QUAD8_DIFF_ENCODER_CABLE_STATUS);
1320 
1321 	mutex_unlock(&priv->lock);
1322 
1323 	return len;
1324 }
1325 
quad8_signal_fck_prescaler_read(struct counter_device * counter,struct counter_signal * signal,void * private,char * buf)1326 static ssize_t quad8_signal_fck_prescaler_read(struct counter_device *counter,
1327 	struct counter_signal *signal, void *private, char *buf)
1328 {
1329 	const struct quad8_iio *const priv = counter->priv;
1330 	const size_t channel_id = signal->id / 2;
1331 
1332 	return sprintf(buf, "%u\n", priv->fck_prescaler[channel_id]);
1333 }
1334 
quad8_signal_fck_prescaler_write(struct counter_device * counter,struct counter_signal * signal,void * private,const char * buf,size_t len)1335 static ssize_t quad8_signal_fck_prescaler_write(struct counter_device *counter,
1336 	struct counter_signal *signal, void *private, const char *buf,
1337 	size_t len)
1338 {
1339 	struct quad8_iio *const priv = counter->priv;
1340 	const size_t channel_id = signal->id / 2;
1341 	const int base_offset = priv->base + 2 * channel_id;
1342 	u8 prescaler;
1343 	int ret;
1344 
1345 	ret = kstrtou8(buf, 0, &prescaler);
1346 	if (ret)
1347 		return ret;
1348 
1349 	mutex_lock(&priv->lock);
1350 
1351 	priv->fck_prescaler[channel_id] = prescaler;
1352 
1353 	/* Reset Byte Pointer */
1354 	outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP, base_offset + 1);
1355 
1356 	/* Set filter clock factor */
1357 	outb(prescaler, base_offset);
1358 	outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP | QUAD8_RLD_PRESET_PSC,
1359 	     base_offset + 1);
1360 
1361 	mutex_unlock(&priv->lock);
1362 
1363 	return len;
1364 }
1365 
1366 static const struct counter_signal_ext quad8_signal_ext[] = {
1367 	{
1368 		.name = "cable_fault",
1369 		.read = quad8_signal_cable_fault_read
1370 	},
1371 	{
1372 		.name = "cable_fault_enable",
1373 		.read = quad8_signal_cable_fault_enable_read,
1374 		.write = quad8_signal_cable_fault_enable_write
1375 	},
1376 	{
1377 		.name = "filter_clock_prescaler",
1378 		.read = quad8_signal_fck_prescaler_read,
1379 		.write = quad8_signal_fck_prescaler_write
1380 	}
1381 };
1382 
1383 static const struct counter_signal_ext quad8_index_ext[] = {
1384 	COUNTER_SIGNAL_ENUM("index_polarity", &quad8_index_pol_enum),
1385 	COUNTER_SIGNAL_ENUM_AVAILABLE("index_polarity",	&quad8_index_pol_enum),
1386 	COUNTER_SIGNAL_ENUM("synchronous_mode", &quad8_syn_mode_enum),
1387 	COUNTER_SIGNAL_ENUM_AVAILABLE("synchronous_mode", &quad8_syn_mode_enum)
1388 };
1389 
1390 #define QUAD8_QUAD_SIGNAL(_id, _name) {		\
1391 	.id = (_id),				\
1392 	.name = (_name),			\
1393 	.ext = quad8_signal_ext,		\
1394 	.num_ext = ARRAY_SIZE(quad8_signal_ext)	\
1395 }
1396 
1397 #define	QUAD8_INDEX_SIGNAL(_id, _name) {	\
1398 	.id = (_id),				\
1399 	.name = (_name),			\
1400 	.ext = quad8_index_ext,			\
1401 	.num_ext = ARRAY_SIZE(quad8_index_ext)	\
1402 }
1403 
1404 static struct counter_signal quad8_signals[] = {
1405 	QUAD8_QUAD_SIGNAL(0, "Channel 1 Quadrature A"),
1406 	QUAD8_QUAD_SIGNAL(1, "Channel 1 Quadrature B"),
1407 	QUAD8_QUAD_SIGNAL(2, "Channel 2 Quadrature A"),
1408 	QUAD8_QUAD_SIGNAL(3, "Channel 2 Quadrature B"),
1409 	QUAD8_QUAD_SIGNAL(4, "Channel 3 Quadrature A"),
1410 	QUAD8_QUAD_SIGNAL(5, "Channel 3 Quadrature B"),
1411 	QUAD8_QUAD_SIGNAL(6, "Channel 4 Quadrature A"),
1412 	QUAD8_QUAD_SIGNAL(7, "Channel 4 Quadrature B"),
1413 	QUAD8_QUAD_SIGNAL(8, "Channel 5 Quadrature A"),
1414 	QUAD8_QUAD_SIGNAL(9, "Channel 5 Quadrature B"),
1415 	QUAD8_QUAD_SIGNAL(10, "Channel 6 Quadrature A"),
1416 	QUAD8_QUAD_SIGNAL(11, "Channel 6 Quadrature B"),
1417 	QUAD8_QUAD_SIGNAL(12, "Channel 7 Quadrature A"),
1418 	QUAD8_QUAD_SIGNAL(13, "Channel 7 Quadrature B"),
1419 	QUAD8_QUAD_SIGNAL(14, "Channel 8 Quadrature A"),
1420 	QUAD8_QUAD_SIGNAL(15, "Channel 8 Quadrature B"),
1421 	QUAD8_INDEX_SIGNAL(16, "Channel 1 Index"),
1422 	QUAD8_INDEX_SIGNAL(17, "Channel 2 Index"),
1423 	QUAD8_INDEX_SIGNAL(18, "Channel 3 Index"),
1424 	QUAD8_INDEX_SIGNAL(19, "Channel 4 Index"),
1425 	QUAD8_INDEX_SIGNAL(20, "Channel 5 Index"),
1426 	QUAD8_INDEX_SIGNAL(21, "Channel 6 Index"),
1427 	QUAD8_INDEX_SIGNAL(22, "Channel 7 Index"),
1428 	QUAD8_INDEX_SIGNAL(23, "Channel 8 Index")
1429 };
1430 
1431 #define QUAD8_COUNT_SYNAPSES(_id) {					\
1432 	{								\
1433 		.actions_list = quad8_synapse_actions_list,		\
1434 		.num_actions = ARRAY_SIZE(quad8_synapse_actions_list),	\
1435 		.signal = quad8_signals + 2 * (_id)			\
1436 	},								\
1437 	{								\
1438 		.actions_list = quad8_synapse_actions_list,		\
1439 		.num_actions = ARRAY_SIZE(quad8_synapse_actions_list),	\
1440 		.signal = quad8_signals + 2 * (_id) + 1			\
1441 	},								\
1442 	{								\
1443 		.actions_list = quad8_index_actions_list,		\
1444 		.num_actions = ARRAY_SIZE(quad8_index_actions_list),	\
1445 		.signal = quad8_signals + 2 * (_id) + 16		\
1446 	}								\
1447 }
1448 
1449 static struct counter_synapse quad8_count_synapses[][3] = {
1450 	QUAD8_COUNT_SYNAPSES(0), QUAD8_COUNT_SYNAPSES(1),
1451 	QUAD8_COUNT_SYNAPSES(2), QUAD8_COUNT_SYNAPSES(3),
1452 	QUAD8_COUNT_SYNAPSES(4), QUAD8_COUNT_SYNAPSES(5),
1453 	QUAD8_COUNT_SYNAPSES(6), QUAD8_COUNT_SYNAPSES(7)
1454 };
1455 
1456 static const struct counter_count_ext quad8_count_ext[] = {
1457 	{
1458 		.name = "ceiling",
1459 		.read = quad8_count_ceiling_read,
1460 		.write = quad8_count_ceiling_write
1461 	},
1462 	{
1463 		.name = "floor",
1464 		.read = quad8_count_floor_read
1465 	},
1466 	COUNTER_COUNT_ENUM("count_mode", &quad8_cnt_mode_enum),
1467 	COUNTER_COUNT_ENUM_AVAILABLE("count_mode", &quad8_cnt_mode_enum),
1468 	{
1469 		.name = "direction",
1470 		.read = quad8_count_direction_read
1471 	},
1472 	{
1473 		.name = "enable",
1474 		.read = quad8_count_enable_read,
1475 		.write = quad8_count_enable_write
1476 	},
1477 	COUNTER_COUNT_ENUM("error_noise", &quad8_error_noise_enum),
1478 	COUNTER_COUNT_ENUM_AVAILABLE("error_noise", &quad8_error_noise_enum),
1479 	{
1480 		.name = "preset",
1481 		.read = quad8_count_preset_read,
1482 		.write = quad8_count_preset_write
1483 	},
1484 	{
1485 		.name = "preset_enable",
1486 		.read = quad8_count_preset_enable_read,
1487 		.write = quad8_count_preset_enable_write
1488 	}
1489 };
1490 
1491 #define QUAD8_COUNT(_id, _cntname) {					\
1492 	.id = (_id),							\
1493 	.name = (_cntname),						\
1494 	.functions_list = quad8_count_functions_list,			\
1495 	.num_functions = ARRAY_SIZE(quad8_count_functions_list),	\
1496 	.synapses = quad8_count_synapses[(_id)],			\
1497 	.num_synapses =	2,						\
1498 	.ext = quad8_count_ext,						\
1499 	.num_ext = ARRAY_SIZE(quad8_count_ext)				\
1500 }
1501 
1502 static struct counter_count quad8_counts[] = {
1503 	QUAD8_COUNT(0, "Channel 1 Count"),
1504 	QUAD8_COUNT(1, "Channel 2 Count"),
1505 	QUAD8_COUNT(2, "Channel 3 Count"),
1506 	QUAD8_COUNT(3, "Channel 4 Count"),
1507 	QUAD8_COUNT(4, "Channel 5 Count"),
1508 	QUAD8_COUNT(5, "Channel 6 Count"),
1509 	QUAD8_COUNT(6, "Channel 7 Count"),
1510 	QUAD8_COUNT(7, "Channel 8 Count")
1511 };
1512 
quad8_probe(struct device * dev,unsigned int id)1513 static int quad8_probe(struct device *dev, unsigned int id)
1514 {
1515 	struct iio_dev *indio_dev;
1516 	struct quad8_iio *quad8iio;
1517 	int i, j;
1518 	unsigned int base_offset;
1519 	int err;
1520 
1521 	if (!devm_request_region(dev, base[id], QUAD8_EXTENT, dev_name(dev))) {
1522 		dev_err(dev, "Unable to lock port addresses (0x%X-0x%X)\n",
1523 			base[id], base[id] + QUAD8_EXTENT);
1524 		return -EBUSY;
1525 	}
1526 
1527 	/* Allocate IIO device; this also allocates driver data structure */
1528 	indio_dev = devm_iio_device_alloc(dev, sizeof(*quad8iio));
1529 	if (!indio_dev)
1530 		return -ENOMEM;
1531 
1532 	/* Initialize IIO device */
1533 	indio_dev->info = &quad8_info;
1534 	indio_dev->modes = INDIO_DIRECT_MODE;
1535 	indio_dev->num_channels = ARRAY_SIZE(quad8_channels);
1536 	indio_dev->channels = quad8_channels;
1537 	indio_dev->name = dev_name(dev);
1538 
1539 	/* Initialize Counter device and driver data */
1540 	quad8iio = iio_priv(indio_dev);
1541 	quad8iio->counter.name = dev_name(dev);
1542 	quad8iio->counter.parent = dev;
1543 	quad8iio->counter.ops = &quad8_ops;
1544 	quad8iio->counter.counts = quad8_counts;
1545 	quad8iio->counter.num_counts = ARRAY_SIZE(quad8_counts);
1546 	quad8iio->counter.signals = quad8_signals;
1547 	quad8iio->counter.num_signals = ARRAY_SIZE(quad8_signals);
1548 	quad8iio->counter.priv = quad8iio;
1549 	quad8iio->base = base[id];
1550 
1551 	/* Initialize mutex */
1552 	mutex_init(&quad8iio->lock);
1553 
1554 	/* Reset all counters and disable interrupt function */
1555 	outb(QUAD8_CHAN_OP_RESET_COUNTERS, base[id] + QUAD8_REG_CHAN_OP);
1556 	/* Set initial configuration for all counters */
1557 	for (i = 0; i < QUAD8_NUM_COUNTERS; i++) {
1558 		base_offset = base[id] + 2 * i;
1559 		/* Reset Byte Pointer */
1560 		outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP, base_offset + 1);
1561 		/* Reset filter clock factor */
1562 		outb(0, base_offset);
1563 		outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP | QUAD8_RLD_PRESET_PSC,
1564 		     base_offset + 1);
1565 		/* Reset Byte Pointer */
1566 		outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_BP, base_offset + 1);
1567 		/* Reset Preset Register */
1568 		for (j = 0; j < 3; j++)
1569 			outb(0x00, base_offset);
1570 		/* Reset Borrow, Carry, Compare, and Sign flags */
1571 		outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_FLAGS, base_offset + 1);
1572 		/* Reset Error flag */
1573 		outb(QUAD8_CTR_RLD | QUAD8_RLD_RESET_E, base_offset + 1);
1574 		/* Binary encoding; Normal count; non-quadrature mode */
1575 		outb(QUAD8_CTR_CMR, base_offset + 1);
1576 		/* Disable A and B inputs; preset on index; FLG1 as Carry */
1577 		outb(QUAD8_CTR_IOR, base_offset + 1);
1578 		/* Disable index function; negative index polarity */
1579 		outb(QUAD8_CTR_IDR, base_offset + 1);
1580 	}
1581 	/* Disable Differential Encoder Cable Status for all channels */
1582 	outb(0xFF, base[id] + QUAD8_DIFF_ENCODER_CABLE_STATUS);
1583 	/* Enable all counters */
1584 	outb(QUAD8_CHAN_OP_ENABLE_COUNTERS, base[id] + QUAD8_REG_CHAN_OP);
1585 
1586 	/* Register IIO device */
1587 	err = devm_iio_device_register(dev, indio_dev);
1588 	if (err)
1589 		return err;
1590 
1591 	/* Register Counter device */
1592 	return devm_counter_register(dev, &quad8iio->counter);
1593 }
1594 
1595 static struct isa_driver quad8_driver = {
1596 	.probe = quad8_probe,
1597 	.driver = {
1598 		.name = "104-quad-8"
1599 	}
1600 };
1601 
1602 module_isa_driver(quad8_driver, num_quad8);
1603 
1604 MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>");
1605 MODULE_DESCRIPTION("ACCES 104-QUAD-8 IIO driver");
1606 MODULE_LICENSE("GPL v2");
1607