xref: /linux/drivers/mfd/iqs62x.c (revision 24bce201d79807b668bf9d9e0aca801c5c0d5f78)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Azoteq IQS620A/621/622/624/625 Multi-Function Sensors
4  *
5  * Copyright (C) 2019 Jeff LaBundy <jeff@labundy.com>
6  *
7  * These devices rely on application-specific register settings and calibration
8  * data developed in and exported from a suite of GUIs offered by the vendor. A
9  * separate tool converts the GUIs' ASCII-based output into a standard firmware
10  * file parsed by the driver.
11  *
12  * Link to datasheets and GUIs: https://www.azoteq.com/
13  *
14  * Link to conversion tool: https://github.com/jlabundy/iqs62x-h2bin.git
15  */
16 
17 #include <linux/completion.h>
18 #include <linux/delay.h>
19 #include <linux/device.h>
20 #include <linux/err.h>
21 #include <linux/firmware.h>
22 #include <linux/i2c.h>
23 #include <linux/interrupt.h>
24 #include <linux/kernel.h>
25 #include <linux/list.h>
26 #include <linux/mfd/core.h>
27 #include <linux/mfd/iqs62x.h>
28 #include <linux/module.h>
29 #include <linux/notifier.h>
30 #include <linux/of_device.h>
31 #include <linux/property.h>
32 #include <linux/regmap.h>
33 #include <linux/slab.h>
34 #include <asm/unaligned.h>
35 
36 #define IQS62X_PROD_NUM				0x00
37 
38 #define IQS62X_SYS_FLAGS			0x10
39 
40 #define IQS620_HALL_FLAGS			0x16
41 #define IQS621_HALL_FLAGS			0x19
42 #define IQS622_HALL_FLAGS			IQS621_HALL_FLAGS
43 
44 #define IQS624_INTERVAL_NUM			0x18
45 #define IQS625_INTERVAL_NUM			0x12
46 
47 #define IQS622_PROX_SETTINGS_4			0x48
48 #define IQS620_PROX_SETTINGS_4			0x50
49 #define IQS620_PROX_SETTINGS_4_SAR_EN		BIT(7)
50 
51 #define IQS621_ALS_CAL_DIV_LUX			0x82
52 #define IQS621_ALS_CAL_DIV_IR			0x83
53 
54 #define IQS620_TEMP_CAL_MULT			0xC2
55 #define IQS620_TEMP_CAL_DIV			0xC3
56 #define IQS620_TEMP_CAL_OFFS			0xC4
57 
58 #define IQS62X_SYS_SETTINGS			0xD0
59 #define IQS62X_SYS_SETTINGS_ACK_RESET		BIT(6)
60 #define IQS62X_SYS_SETTINGS_EVENT_MODE		BIT(5)
61 #define IQS62X_SYS_SETTINGS_CLK_DIV		BIT(4)
62 #define IQS62X_SYS_SETTINGS_COMM_ATI		BIT(3)
63 #define IQS62X_SYS_SETTINGS_REDO_ATI		BIT(1)
64 
65 #define IQS62X_PWR_SETTINGS			0xD2
66 #define IQS62X_PWR_SETTINGS_DIS_AUTO		BIT(5)
67 #define IQS62X_PWR_SETTINGS_PWR_MODE_MASK	(BIT(4) | BIT(3))
68 #define IQS62X_PWR_SETTINGS_PWR_MODE_HALT	(BIT(4) | BIT(3))
69 #define IQS62X_PWR_SETTINGS_PWR_MODE_NORM	0
70 
71 #define IQS62X_OTP_CMD				0xF0
72 #define IQS62X_OTP_CMD_FG3			0x13
73 #define IQS62X_OTP_DATA				0xF1
74 #define IQS62X_MAX_REG				0xFF
75 
76 #define IQS62X_HALL_CAL_MASK			GENMASK(3, 0)
77 
78 #define IQS62X_FW_REC_TYPE_INFO			0
79 #define IQS62X_FW_REC_TYPE_PROD			1
80 #define IQS62X_FW_REC_TYPE_HALL			2
81 #define IQS62X_FW_REC_TYPE_MASK			3
82 #define IQS62X_FW_REC_TYPE_DATA			4
83 
84 #define IQS62X_ATI_STARTUP_MS			350
85 #define IQS62X_FILT_SETTLE_MS			250
86 
87 struct iqs62x_fw_rec {
88 	u8 type;
89 	u8 addr;
90 	u8 len;
91 	u8 data;
92 } __packed;
93 
94 struct iqs62x_fw_blk {
95 	struct list_head list;
96 	u8 addr;
97 	u8 mask;
98 	u8 len;
99 	u8 data[];
100 };
101 
102 struct iqs62x_info {
103 	u8 prod_num;
104 	u8 sw_num;
105 	u8 hw_num;
106 } __packed;
107 
108 static int iqs62x_dev_init(struct iqs62x_core *iqs62x)
109 {
110 	struct iqs62x_fw_blk *fw_blk;
111 	unsigned int val;
112 	int ret;
113 
114 	list_for_each_entry(fw_blk, &iqs62x->fw_blk_head, list) {
115 		/*
116 		 * In case ATI is in progress, wait for it to complete before
117 		 * lowering the core clock frequency.
118 		 */
119 		if (fw_blk->addr == IQS62X_SYS_SETTINGS &&
120 		    *fw_blk->data & IQS62X_SYS_SETTINGS_CLK_DIV)
121 			msleep(IQS62X_ATI_STARTUP_MS);
122 
123 		if (fw_blk->mask)
124 			ret = regmap_update_bits(iqs62x->regmap, fw_blk->addr,
125 						 fw_blk->mask, *fw_blk->data);
126 		else
127 			ret = regmap_raw_write(iqs62x->regmap, fw_blk->addr,
128 					       fw_blk->data, fw_blk->len);
129 		if (ret)
130 			return ret;
131 	}
132 
133 	switch (iqs62x->dev_desc->prod_num) {
134 	case IQS620_PROD_NUM:
135 	case IQS622_PROD_NUM:
136 		ret = regmap_read(iqs62x->regmap,
137 				  iqs62x->dev_desc->prox_settings, &val);
138 		if (ret)
139 			return ret;
140 
141 		if (val & IQS620_PROX_SETTINGS_4_SAR_EN)
142 			iqs62x->ui_sel = IQS62X_UI_SAR1;
143 		fallthrough;
144 
145 	case IQS621_PROD_NUM:
146 		ret = regmap_write(iqs62x->regmap, IQS620_GLBL_EVENT_MASK,
147 				   IQS620_GLBL_EVENT_MASK_PMU |
148 				   iqs62x->dev_desc->prox_mask |
149 				   iqs62x->dev_desc->sar_mask |
150 				   iqs62x->dev_desc->hall_mask |
151 				   iqs62x->dev_desc->hyst_mask |
152 				   iqs62x->dev_desc->temp_mask |
153 				   iqs62x->dev_desc->als_mask |
154 				   iqs62x->dev_desc->ir_mask);
155 		if (ret)
156 			return ret;
157 		break;
158 
159 	default:
160 		ret = regmap_write(iqs62x->regmap, IQS624_HALL_UI,
161 				   IQS624_HALL_UI_WHL_EVENT |
162 				   IQS624_HALL_UI_INT_EVENT |
163 				   IQS624_HALL_UI_AUTO_CAL);
164 		if (ret)
165 			return ret;
166 
167 		/*
168 		 * The IQS625 default interval divider is below the minimum
169 		 * permissible value, and the datasheet mandates that it is
170 		 * corrected during initialization (unless an updated value
171 		 * has already been provided by firmware).
172 		 *
173 		 * To protect against an unacceptably low user-entered value
174 		 * stored in the firmware, the same check is extended to the
175 		 * IQS624 as well.
176 		 */
177 		ret = regmap_read(iqs62x->regmap, IQS624_INTERVAL_DIV, &val);
178 		if (ret)
179 			return ret;
180 
181 		if (val >= iqs62x->dev_desc->interval_div)
182 			break;
183 
184 		ret = regmap_write(iqs62x->regmap, IQS624_INTERVAL_DIV,
185 				   iqs62x->dev_desc->interval_div);
186 		if (ret)
187 			return ret;
188 	}
189 
190 	/*
191 	 * Place the device in streaming mode at first so as not to miss the
192 	 * limited number of interrupts that would otherwise occur after ATI
193 	 * completes. The device is subsequently placed in event mode by the
194 	 * interrupt handler.
195 	 *
196 	 * In the meantime, mask interrupts during ATI to prevent the device
197 	 * from soliciting I2C traffic until the noise-sensitive ATI process
198 	 * is complete.
199 	 */
200 	ret = regmap_update_bits(iqs62x->regmap, IQS62X_SYS_SETTINGS,
201 				 IQS62X_SYS_SETTINGS_ACK_RESET |
202 				 IQS62X_SYS_SETTINGS_EVENT_MODE |
203 				 IQS62X_SYS_SETTINGS_COMM_ATI |
204 				 IQS62X_SYS_SETTINGS_REDO_ATI,
205 				 IQS62X_SYS_SETTINGS_ACK_RESET |
206 				 IQS62X_SYS_SETTINGS_REDO_ATI);
207 	if (ret)
208 		return ret;
209 
210 	/*
211 	 * The following delay gives the device time to deassert its RDY output
212 	 * in case a communication window was open while the REDO_ATI field was
213 	 * written. This prevents an interrupt from being serviced prematurely.
214 	 */
215 	usleep_range(5000, 5100);
216 
217 	return 0;
218 }
219 
220 static int iqs62x_firmware_parse(struct iqs62x_core *iqs62x,
221 				 const struct firmware *fw)
222 {
223 	struct i2c_client *client = iqs62x->client;
224 	struct iqs62x_fw_rec *fw_rec;
225 	struct iqs62x_fw_blk *fw_blk;
226 	unsigned int val;
227 	size_t pos = 0;
228 	int ret = 0;
229 	u8 mask, len, *data;
230 	u8 hall_cal_index = 0;
231 
232 	while (pos < fw->size) {
233 		if (pos + sizeof(*fw_rec) > fw->size) {
234 			ret = -EINVAL;
235 			break;
236 		}
237 		fw_rec = (struct iqs62x_fw_rec *)(fw->data + pos);
238 		pos += sizeof(*fw_rec);
239 
240 		if (pos + fw_rec->len - 1 > fw->size) {
241 			ret = -EINVAL;
242 			break;
243 		}
244 		pos += fw_rec->len - 1;
245 
246 		switch (fw_rec->type) {
247 		case IQS62X_FW_REC_TYPE_INFO:
248 			continue;
249 
250 		case IQS62X_FW_REC_TYPE_PROD:
251 			if (fw_rec->data == iqs62x->dev_desc->prod_num)
252 				continue;
253 
254 			dev_err(&client->dev,
255 				"Incompatible product number: 0x%02X\n",
256 				fw_rec->data);
257 			ret = -EINVAL;
258 			break;
259 
260 		case IQS62X_FW_REC_TYPE_HALL:
261 			if (!hall_cal_index) {
262 				ret = regmap_write(iqs62x->regmap,
263 						   IQS62X_OTP_CMD,
264 						   IQS62X_OTP_CMD_FG3);
265 				if (ret)
266 					break;
267 
268 				ret = regmap_read(iqs62x->regmap,
269 						  IQS62X_OTP_DATA, &val);
270 				if (ret)
271 					break;
272 
273 				hall_cal_index = val & IQS62X_HALL_CAL_MASK;
274 				if (!hall_cal_index) {
275 					dev_err(&client->dev,
276 						"Uncalibrated device\n");
277 					ret = -ENODATA;
278 					break;
279 				}
280 			}
281 
282 			if (hall_cal_index > fw_rec->len) {
283 				ret = -EINVAL;
284 				break;
285 			}
286 
287 			mask = 0;
288 			data = &fw_rec->data + hall_cal_index - 1;
289 			len = sizeof(*data);
290 			break;
291 
292 		case IQS62X_FW_REC_TYPE_MASK:
293 			if (fw_rec->len < (sizeof(mask) + sizeof(*data))) {
294 				ret = -EINVAL;
295 				break;
296 			}
297 
298 			mask = fw_rec->data;
299 			data = &fw_rec->data + sizeof(mask);
300 			len = sizeof(*data);
301 			break;
302 
303 		case IQS62X_FW_REC_TYPE_DATA:
304 			mask = 0;
305 			data = &fw_rec->data;
306 			len = fw_rec->len;
307 			break;
308 
309 		default:
310 			dev_err(&client->dev,
311 				"Unrecognized record type: 0x%02X\n",
312 				fw_rec->type);
313 			ret = -EINVAL;
314 		}
315 
316 		if (ret)
317 			break;
318 
319 		fw_blk = devm_kzalloc(&client->dev,
320 				      struct_size(fw_blk, data, len),
321 				      GFP_KERNEL);
322 		if (!fw_blk) {
323 			ret = -ENOMEM;
324 			break;
325 		}
326 
327 		fw_blk->addr = fw_rec->addr;
328 		fw_blk->mask = mask;
329 		fw_blk->len = len;
330 		memcpy(fw_blk->data, data, len);
331 
332 		list_add(&fw_blk->list, &iqs62x->fw_blk_head);
333 	}
334 
335 	release_firmware(fw);
336 
337 	return ret;
338 }
339 
340 const struct iqs62x_event_desc iqs62x_events[IQS62X_NUM_EVENTS] = {
341 	[IQS62X_EVENT_PROX_CH0_T] = {
342 		.reg	= IQS62X_EVENT_PROX,
343 		.mask	= BIT(4),
344 		.val	= BIT(4),
345 	},
346 	[IQS62X_EVENT_PROX_CH0_P] = {
347 		.reg	= IQS62X_EVENT_PROX,
348 		.mask	= BIT(0),
349 		.val	= BIT(0),
350 	},
351 	[IQS62X_EVENT_PROX_CH1_T] = {
352 		.reg	= IQS62X_EVENT_PROX,
353 		.mask	= BIT(5),
354 		.val	= BIT(5),
355 	},
356 	[IQS62X_EVENT_PROX_CH1_P] = {
357 		.reg	= IQS62X_EVENT_PROX,
358 		.mask	= BIT(1),
359 		.val	= BIT(1),
360 	},
361 	[IQS62X_EVENT_PROX_CH2_T] = {
362 		.reg	= IQS62X_EVENT_PROX,
363 		.mask	= BIT(6),
364 		.val	= BIT(6),
365 	},
366 	[IQS62X_EVENT_PROX_CH2_P] = {
367 		.reg	= IQS62X_EVENT_PROX,
368 		.mask	= BIT(2),
369 		.val	= BIT(2),
370 	},
371 	[IQS62X_EVENT_HYST_POS_T] = {
372 		.reg	= IQS62X_EVENT_HYST,
373 		.mask	= BIT(6) | BIT(7),
374 		.val	= BIT(6),
375 	},
376 	[IQS62X_EVENT_HYST_POS_P] = {
377 		.reg	= IQS62X_EVENT_HYST,
378 		.mask	= BIT(5) | BIT(7),
379 		.val	= BIT(5),
380 	},
381 	[IQS62X_EVENT_HYST_NEG_T] = {
382 		.reg	= IQS62X_EVENT_HYST,
383 		.mask	= BIT(6) | BIT(7),
384 		.val	= BIT(6) | BIT(7),
385 	},
386 	[IQS62X_EVENT_HYST_NEG_P] = {
387 		.reg	= IQS62X_EVENT_HYST,
388 		.mask	= BIT(5) | BIT(7),
389 		.val	= BIT(5) | BIT(7),
390 	},
391 	[IQS62X_EVENT_SAR1_ACT] = {
392 		.reg	= IQS62X_EVENT_HYST,
393 		.mask	= BIT(4),
394 		.val	= BIT(4),
395 	},
396 	[IQS62X_EVENT_SAR1_QRD] = {
397 		.reg	= IQS62X_EVENT_HYST,
398 		.mask	= BIT(2),
399 		.val	= BIT(2),
400 	},
401 	[IQS62X_EVENT_SAR1_MOVE] = {
402 		.reg	= IQS62X_EVENT_HYST,
403 		.mask	= BIT(1),
404 		.val	= BIT(1),
405 	},
406 	[IQS62X_EVENT_SAR1_HALT] = {
407 		.reg	= IQS62X_EVENT_HYST,
408 		.mask	= BIT(0),
409 		.val	= BIT(0),
410 	},
411 	[IQS62X_EVENT_WHEEL_UP] = {
412 		.reg	= IQS62X_EVENT_WHEEL,
413 		.mask	= BIT(7) | BIT(6),
414 		.val	= BIT(7),
415 	},
416 	[IQS62X_EVENT_WHEEL_DN] = {
417 		.reg	= IQS62X_EVENT_WHEEL,
418 		.mask	= BIT(7) | BIT(6),
419 		.val	= BIT(7) | BIT(6),
420 	},
421 	[IQS62X_EVENT_HALL_N_T] = {
422 		.reg	= IQS62X_EVENT_HALL,
423 		.mask	= BIT(2) | BIT(0),
424 		.val	= BIT(2),
425 	},
426 	[IQS62X_EVENT_HALL_N_P] = {
427 		.reg	= IQS62X_EVENT_HALL,
428 		.mask	= BIT(1) | BIT(0),
429 		.val	= BIT(1),
430 	},
431 	[IQS62X_EVENT_HALL_S_T] = {
432 		.reg	= IQS62X_EVENT_HALL,
433 		.mask	= BIT(2) | BIT(0),
434 		.val	= BIT(2) | BIT(0),
435 	},
436 	[IQS62X_EVENT_HALL_S_P] = {
437 		.reg	= IQS62X_EVENT_HALL,
438 		.mask	= BIT(1) | BIT(0),
439 		.val	= BIT(1) | BIT(0),
440 	},
441 	[IQS62X_EVENT_SYS_RESET] = {
442 		.reg	= IQS62X_EVENT_SYS,
443 		.mask	= BIT(7),
444 		.val	= BIT(7),
445 	},
446 	[IQS62X_EVENT_SYS_ATI] = {
447 		.reg	= IQS62X_EVENT_SYS,
448 		.mask	= BIT(2),
449 		.val	= BIT(2),
450 	},
451 };
452 EXPORT_SYMBOL_GPL(iqs62x_events);
453 
454 static irqreturn_t iqs62x_irq(int irq, void *context)
455 {
456 	struct iqs62x_core *iqs62x = context;
457 	struct i2c_client *client = iqs62x->client;
458 	struct iqs62x_event_data event_data;
459 	struct iqs62x_event_desc event_desc;
460 	enum iqs62x_event_reg event_reg;
461 	unsigned long event_flags = 0;
462 	int ret, i, j;
463 	u8 event_map[IQS62X_EVENT_SIZE];
464 
465 	/*
466 	 * The device asserts the RDY output to signal the beginning of a
467 	 * communication window, which is closed by an I2C stop condition.
468 	 * As such, all interrupt status is captured in a single read and
469 	 * broadcast to any interested sub-device drivers.
470 	 */
471 	ret = regmap_raw_read(iqs62x->regmap, IQS62X_SYS_FLAGS, event_map,
472 			      sizeof(event_map));
473 	if (ret) {
474 		dev_err(&client->dev, "Failed to read device status: %d\n",
475 			ret);
476 		return IRQ_NONE;
477 	}
478 
479 	for (i = 0; i < sizeof(event_map); i++) {
480 		event_reg = iqs62x->dev_desc->event_regs[iqs62x->ui_sel][i];
481 
482 		switch (event_reg) {
483 		case IQS62X_EVENT_UI_LO:
484 			event_data.ui_data = get_unaligned_le16(&event_map[i]);
485 			fallthrough;
486 
487 		case IQS62X_EVENT_UI_HI:
488 		case IQS62X_EVENT_NONE:
489 			continue;
490 
491 		case IQS62X_EVENT_ALS:
492 			event_data.als_flags = event_map[i];
493 			continue;
494 
495 		case IQS62X_EVENT_IR:
496 			event_data.ir_flags = event_map[i];
497 			continue;
498 
499 		case IQS62X_EVENT_INTER:
500 			event_data.interval = event_map[i];
501 			continue;
502 
503 		case IQS62X_EVENT_HYST:
504 			event_map[i] <<= iqs62x->dev_desc->hyst_shift;
505 			fallthrough;
506 
507 		case IQS62X_EVENT_WHEEL:
508 		case IQS62X_EVENT_HALL:
509 		case IQS62X_EVENT_PROX:
510 		case IQS62X_EVENT_SYS:
511 			break;
512 		}
513 
514 		for (j = 0; j < IQS62X_NUM_EVENTS; j++) {
515 			event_desc = iqs62x_events[j];
516 
517 			if (event_desc.reg != event_reg)
518 				continue;
519 
520 			if ((event_map[i] & event_desc.mask) == event_desc.val)
521 				event_flags |= BIT(j);
522 		}
523 	}
524 
525 	/*
526 	 * The device resets itself in response to the I2C master stalling
527 	 * communication past a fixed timeout. In this case, all registers
528 	 * are restored and any interested sub-device drivers are notified.
529 	 */
530 	if (event_flags & BIT(IQS62X_EVENT_SYS_RESET)) {
531 		dev_err(&client->dev, "Unexpected device reset\n");
532 
533 		ret = iqs62x_dev_init(iqs62x);
534 		if (ret) {
535 			dev_err(&client->dev,
536 				"Failed to re-initialize device: %d\n", ret);
537 			return IRQ_NONE;
538 		}
539 
540 		iqs62x->event_cache |= BIT(IQS62X_EVENT_SYS_RESET);
541 		reinit_completion(&iqs62x->ati_done);
542 	} else if (event_flags & BIT(IQS62X_EVENT_SYS_ATI)) {
543 		iqs62x->event_cache |= BIT(IQS62X_EVENT_SYS_ATI);
544 		reinit_completion(&iqs62x->ati_done);
545 	} else if (!completion_done(&iqs62x->ati_done)) {
546 		ret = regmap_update_bits(iqs62x->regmap, IQS62X_SYS_SETTINGS,
547 					 IQS62X_SYS_SETTINGS_EVENT_MODE, 0xFF);
548 		if (ret) {
549 			dev_err(&client->dev,
550 				"Failed to enable event mode: %d\n", ret);
551 			return IRQ_NONE;
552 		}
553 
554 		msleep(IQS62X_FILT_SETTLE_MS);
555 		complete_all(&iqs62x->ati_done);
556 	}
557 
558 	/*
559 	 * Reset and ATI events are not broadcast to the sub-device drivers
560 	 * until ATI has completed. Any other events that may have occurred
561 	 * during ATI are ignored.
562 	 */
563 	if (completion_done(&iqs62x->ati_done)) {
564 		event_flags |= iqs62x->event_cache;
565 		ret = blocking_notifier_call_chain(&iqs62x->nh, event_flags,
566 						   &event_data);
567 		if (ret & NOTIFY_STOP_MASK)
568 			return IRQ_NONE;
569 
570 		iqs62x->event_cache = 0;
571 	}
572 
573 	/*
574 	 * Once the communication window is closed, a small delay is added to
575 	 * ensure the device's RDY output has been deasserted by the time the
576 	 * interrupt handler returns.
577 	 */
578 	usleep_range(150, 200);
579 
580 	return IRQ_HANDLED;
581 }
582 
583 static void iqs62x_firmware_load(const struct firmware *fw, void *context)
584 {
585 	struct iqs62x_core *iqs62x = context;
586 	struct i2c_client *client = iqs62x->client;
587 	int ret;
588 
589 	if (fw) {
590 		ret = iqs62x_firmware_parse(iqs62x, fw);
591 		if (ret) {
592 			dev_err(&client->dev, "Failed to parse firmware: %d\n",
593 				ret);
594 			goto err_out;
595 		}
596 	}
597 
598 	ret = iqs62x_dev_init(iqs62x);
599 	if (ret) {
600 		dev_err(&client->dev, "Failed to initialize device: %d\n", ret);
601 		goto err_out;
602 	}
603 
604 	ret = devm_request_threaded_irq(&client->dev, client->irq,
605 					NULL, iqs62x_irq, IRQF_ONESHOT,
606 					client->name, iqs62x);
607 	if (ret) {
608 		dev_err(&client->dev, "Failed to request IRQ: %d\n", ret);
609 		goto err_out;
610 	}
611 
612 	if (!wait_for_completion_timeout(&iqs62x->ati_done,
613 					 msecs_to_jiffies(2000))) {
614 		dev_err(&client->dev, "Failed to complete ATI\n");
615 		goto err_out;
616 	}
617 
618 	ret = devm_mfd_add_devices(&client->dev, PLATFORM_DEVID_NONE,
619 				   iqs62x->dev_desc->sub_devs,
620 				   iqs62x->dev_desc->num_sub_devs,
621 				   NULL, 0, NULL);
622 	if (ret)
623 		dev_err(&client->dev, "Failed to add sub-devices: %d\n", ret);
624 
625 err_out:
626 	complete_all(&iqs62x->fw_done);
627 }
628 
629 static const struct mfd_cell iqs620at_sub_devs[] = {
630 	{
631 		.name = "iqs62x-keys",
632 		.of_compatible = "azoteq,iqs620a-keys",
633 	},
634 	{
635 		.name = "iqs620a-pwm",
636 		.of_compatible = "azoteq,iqs620a-pwm",
637 	},
638 	{ .name = "iqs620at-temp", },
639 };
640 
641 static const struct mfd_cell iqs620a_sub_devs[] = {
642 	{
643 		.name = "iqs62x-keys",
644 		.of_compatible = "azoteq,iqs620a-keys",
645 	},
646 	{
647 		.name = "iqs620a-pwm",
648 		.of_compatible = "azoteq,iqs620a-pwm",
649 	},
650 };
651 
652 static const struct mfd_cell iqs621_sub_devs[] = {
653 	{
654 		.name = "iqs62x-keys",
655 		.of_compatible = "azoteq,iqs621-keys",
656 	},
657 	{ .name = "iqs621-als", },
658 };
659 
660 static const struct mfd_cell iqs622_sub_devs[] = {
661 	{
662 		.name = "iqs62x-keys",
663 		.of_compatible = "azoteq,iqs622-keys",
664 	},
665 	{ .name = "iqs621-als", },
666 };
667 
668 static const struct mfd_cell iqs624_sub_devs[] = {
669 	{
670 		.name = "iqs62x-keys",
671 		.of_compatible = "azoteq,iqs624-keys",
672 	},
673 	{ .name = "iqs624-pos", },
674 };
675 
676 static const struct mfd_cell iqs625_sub_devs[] = {
677 	{
678 		.name = "iqs62x-keys",
679 		.of_compatible = "azoteq,iqs625-keys",
680 	},
681 	{ .name = "iqs624-pos", },
682 };
683 
684 static const u8 iqs620at_cal_regs[] = {
685 	IQS620_TEMP_CAL_MULT,
686 	IQS620_TEMP_CAL_DIV,
687 	IQS620_TEMP_CAL_OFFS,
688 };
689 
690 static const u8 iqs621_cal_regs[] = {
691 	IQS621_ALS_CAL_DIV_LUX,
692 	IQS621_ALS_CAL_DIV_IR,
693 };
694 
695 static const enum iqs62x_event_reg iqs620a_event_regs[][IQS62X_EVENT_SIZE] = {
696 	[IQS62X_UI_PROX] = {
697 		IQS62X_EVENT_SYS,	/* 0x10 */
698 		IQS62X_EVENT_NONE,
699 		IQS62X_EVENT_PROX,	/* 0x12 */
700 		IQS62X_EVENT_HYST,	/* 0x13 */
701 		IQS62X_EVENT_NONE,
702 		IQS62X_EVENT_NONE,
703 		IQS62X_EVENT_HALL,	/* 0x16 */
704 		IQS62X_EVENT_NONE,
705 		IQS62X_EVENT_NONE,
706 		IQS62X_EVENT_NONE,
707 	},
708 	[IQS62X_UI_SAR1] = {
709 		IQS62X_EVENT_SYS,	/* 0x10 */
710 		IQS62X_EVENT_NONE,
711 		IQS62X_EVENT_NONE,
712 		IQS62X_EVENT_HYST,	/* 0x13 */
713 		IQS62X_EVENT_NONE,
714 		IQS62X_EVENT_NONE,
715 		IQS62X_EVENT_HALL,	/* 0x16 */
716 		IQS62X_EVENT_NONE,
717 		IQS62X_EVENT_NONE,
718 		IQS62X_EVENT_NONE,
719 	},
720 };
721 
722 static const enum iqs62x_event_reg iqs621_event_regs[][IQS62X_EVENT_SIZE] = {
723 	[IQS62X_UI_PROX] = {
724 		IQS62X_EVENT_SYS,	/* 0x10 */
725 		IQS62X_EVENT_NONE,
726 		IQS62X_EVENT_PROX,	/* 0x12 */
727 		IQS62X_EVENT_HYST,	/* 0x13 */
728 		IQS62X_EVENT_NONE,
729 		IQS62X_EVENT_NONE,
730 		IQS62X_EVENT_ALS,	/* 0x16 */
731 		IQS62X_EVENT_UI_LO,	/* 0x17 */
732 		IQS62X_EVENT_UI_HI,	/* 0x18 */
733 		IQS62X_EVENT_HALL,	/* 0x19 */
734 	},
735 };
736 
737 static const enum iqs62x_event_reg iqs622_event_regs[][IQS62X_EVENT_SIZE] = {
738 	[IQS62X_UI_PROX] = {
739 		IQS62X_EVENT_SYS,	/* 0x10 */
740 		IQS62X_EVENT_NONE,
741 		IQS62X_EVENT_PROX,	/* 0x12 */
742 		IQS62X_EVENT_NONE,
743 		IQS62X_EVENT_ALS,	/* 0x14 */
744 		IQS62X_EVENT_NONE,
745 		IQS62X_EVENT_IR,	/* 0x16 */
746 		IQS62X_EVENT_UI_LO,	/* 0x17 */
747 		IQS62X_EVENT_UI_HI,	/* 0x18 */
748 		IQS62X_EVENT_HALL,	/* 0x19 */
749 	},
750 	[IQS62X_UI_SAR1] = {
751 		IQS62X_EVENT_SYS,	/* 0x10 */
752 		IQS62X_EVENT_NONE,
753 		IQS62X_EVENT_NONE,
754 		IQS62X_EVENT_HYST,	/* 0x13 */
755 		IQS62X_EVENT_ALS,	/* 0x14 */
756 		IQS62X_EVENT_NONE,
757 		IQS62X_EVENT_IR,	/* 0x16 */
758 		IQS62X_EVENT_UI_LO,	/* 0x17 */
759 		IQS62X_EVENT_UI_HI,	/* 0x18 */
760 		IQS62X_EVENT_HALL,	/* 0x19 */
761 	},
762 };
763 
764 static const enum iqs62x_event_reg iqs624_event_regs[][IQS62X_EVENT_SIZE] = {
765 	[IQS62X_UI_PROX] = {
766 		IQS62X_EVENT_SYS,	/* 0x10 */
767 		IQS62X_EVENT_NONE,
768 		IQS62X_EVENT_PROX,	/* 0x12 */
769 		IQS62X_EVENT_NONE,
770 		IQS62X_EVENT_WHEEL,	/* 0x14 */
771 		IQS62X_EVENT_NONE,
772 		IQS62X_EVENT_UI_LO,	/* 0x16 */
773 		IQS62X_EVENT_UI_HI,	/* 0x17 */
774 		IQS62X_EVENT_INTER,	/* 0x18 */
775 		IQS62X_EVENT_NONE,
776 	},
777 };
778 
779 static const enum iqs62x_event_reg iqs625_event_regs[][IQS62X_EVENT_SIZE] = {
780 	[IQS62X_UI_PROX] = {
781 		IQS62X_EVENT_SYS,	/* 0x10 */
782 		IQS62X_EVENT_PROX,	/* 0x11 */
783 		IQS62X_EVENT_INTER,	/* 0x12 */
784 		IQS62X_EVENT_NONE,
785 		IQS62X_EVENT_NONE,
786 		IQS62X_EVENT_NONE,
787 		IQS62X_EVENT_NONE,
788 		IQS62X_EVENT_NONE,
789 		IQS62X_EVENT_NONE,
790 		IQS62X_EVENT_NONE,
791 	},
792 };
793 
794 static const struct iqs62x_dev_desc iqs62x_devs[] = {
795 	{
796 		.dev_name	= "iqs620at",
797 		.sub_devs	= iqs620at_sub_devs,
798 		.num_sub_devs	= ARRAY_SIZE(iqs620at_sub_devs),
799 		.prod_num	= IQS620_PROD_NUM,
800 		.sw_num		= 0x08,
801 		.cal_regs	= iqs620at_cal_regs,
802 		.num_cal_regs	= ARRAY_SIZE(iqs620at_cal_regs),
803 		.prox_mask	= BIT(0),
804 		.sar_mask	= BIT(1) | BIT(7),
805 		.hall_mask	= BIT(2),
806 		.hyst_mask	= BIT(3),
807 		.temp_mask	= BIT(4),
808 		.prox_settings	= IQS620_PROX_SETTINGS_4,
809 		.hall_flags	= IQS620_HALL_FLAGS,
810 		.fw_name	= "iqs620a.bin",
811 		.event_regs	= &iqs620a_event_regs[IQS62X_UI_PROX],
812 	},
813 	{
814 		.dev_name	= "iqs620a",
815 		.sub_devs	= iqs620a_sub_devs,
816 		.num_sub_devs	= ARRAY_SIZE(iqs620a_sub_devs),
817 		.prod_num	= IQS620_PROD_NUM,
818 		.sw_num		= 0x08,
819 		.prox_mask	= BIT(0),
820 		.sar_mask	= BIT(1) | BIT(7),
821 		.hall_mask	= BIT(2),
822 		.hyst_mask	= BIT(3),
823 		.temp_mask	= BIT(4),
824 		.prox_settings	= IQS620_PROX_SETTINGS_4,
825 		.hall_flags	= IQS620_HALL_FLAGS,
826 		.fw_name	= "iqs620a.bin",
827 		.event_regs	= &iqs620a_event_regs[IQS62X_UI_PROX],
828 	},
829 	{
830 		.dev_name	= "iqs621",
831 		.sub_devs	= iqs621_sub_devs,
832 		.num_sub_devs	= ARRAY_SIZE(iqs621_sub_devs),
833 		.prod_num	= IQS621_PROD_NUM,
834 		.sw_num		= 0x09,
835 		.cal_regs	= iqs621_cal_regs,
836 		.num_cal_regs	= ARRAY_SIZE(iqs621_cal_regs),
837 		.prox_mask	= BIT(0),
838 		.hall_mask	= BIT(1),
839 		.als_mask	= BIT(2),
840 		.hyst_mask	= BIT(3),
841 		.temp_mask	= BIT(4),
842 		.als_flags	= IQS621_ALS_FLAGS,
843 		.hall_flags	= IQS621_HALL_FLAGS,
844 		.hyst_shift	= 5,
845 		.fw_name	= "iqs621.bin",
846 		.event_regs	= &iqs621_event_regs[IQS62X_UI_PROX],
847 	},
848 	{
849 		.dev_name	= "iqs622",
850 		.sub_devs	= iqs622_sub_devs,
851 		.num_sub_devs	= ARRAY_SIZE(iqs622_sub_devs),
852 		.prod_num	= IQS622_PROD_NUM,
853 		.sw_num		= 0x06,
854 		.prox_mask	= BIT(0),
855 		.sar_mask	= BIT(1),
856 		.hall_mask	= BIT(2),
857 		.als_mask	= BIT(3),
858 		.ir_mask	= BIT(4),
859 		.prox_settings	= IQS622_PROX_SETTINGS_4,
860 		.als_flags	= IQS622_ALS_FLAGS,
861 		.hall_flags	= IQS622_HALL_FLAGS,
862 		.fw_name	= "iqs622.bin",
863 		.event_regs	= &iqs622_event_regs[IQS62X_UI_PROX],
864 	},
865 	{
866 		.dev_name	= "iqs624",
867 		.sub_devs	= iqs624_sub_devs,
868 		.num_sub_devs	= ARRAY_SIZE(iqs624_sub_devs),
869 		.prod_num	= IQS624_PROD_NUM,
870 		.sw_num		= 0x0B,
871 		.interval	= IQS624_INTERVAL_NUM,
872 		.interval_div	= 3,
873 		.fw_name	= "iqs624.bin",
874 		.event_regs	= &iqs624_event_regs[IQS62X_UI_PROX],
875 	},
876 	{
877 		.dev_name	= "iqs625",
878 		.sub_devs	= iqs625_sub_devs,
879 		.num_sub_devs	= ARRAY_SIZE(iqs625_sub_devs),
880 		.prod_num	= IQS625_PROD_NUM,
881 		.sw_num		= 0x0B,
882 		.interval	= IQS625_INTERVAL_NUM,
883 		.interval_div	= 10,
884 		.fw_name	= "iqs625.bin",
885 		.event_regs	= &iqs625_event_regs[IQS62X_UI_PROX],
886 	},
887 };
888 
889 static const struct regmap_config iqs62x_regmap_config = {
890 	.reg_bits = 8,
891 	.val_bits = 8,
892 	.max_register = IQS62X_MAX_REG,
893 };
894 
895 static int iqs62x_probe(struct i2c_client *client)
896 {
897 	struct iqs62x_core *iqs62x;
898 	struct iqs62x_info info;
899 	unsigned int val;
900 	int ret, i, j;
901 	const char *fw_name = NULL;
902 
903 	iqs62x = devm_kzalloc(&client->dev, sizeof(*iqs62x), GFP_KERNEL);
904 	if (!iqs62x)
905 		return -ENOMEM;
906 
907 	i2c_set_clientdata(client, iqs62x);
908 	iqs62x->client = client;
909 
910 	BLOCKING_INIT_NOTIFIER_HEAD(&iqs62x->nh);
911 	INIT_LIST_HEAD(&iqs62x->fw_blk_head);
912 
913 	init_completion(&iqs62x->ati_done);
914 	init_completion(&iqs62x->fw_done);
915 
916 	iqs62x->regmap = devm_regmap_init_i2c(client, &iqs62x_regmap_config);
917 	if (IS_ERR(iqs62x->regmap)) {
918 		ret = PTR_ERR(iqs62x->regmap);
919 		dev_err(&client->dev, "Failed to initialize register map: %d\n",
920 			ret);
921 		return ret;
922 	}
923 
924 	ret = regmap_raw_read(iqs62x->regmap, IQS62X_PROD_NUM, &info,
925 			      sizeof(info));
926 	if (ret)
927 		return ret;
928 
929 	/*
930 	 * The following sequence validates the device's product and software
931 	 * numbers. It then determines if the device is factory-calibrated by
932 	 * checking for nonzero values in the device's designated calibration
933 	 * registers (if applicable). Depending on the device, the absence of
934 	 * calibration data indicates a reduced feature set or invalid device.
935 	 *
936 	 * For devices given in both calibrated and uncalibrated versions, the
937 	 * calibrated version (e.g. IQS620AT) appears first in the iqs62x_devs
938 	 * array. The uncalibrated version (e.g. IQS620A) appears next and has
939 	 * the same product and software numbers, but no calibration registers
940 	 * are specified.
941 	 */
942 	for (i = 0; i < ARRAY_SIZE(iqs62x_devs); i++) {
943 		if (info.prod_num != iqs62x_devs[i].prod_num)
944 			continue;
945 
946 		iqs62x->dev_desc = &iqs62x_devs[i];
947 
948 		if (info.sw_num < iqs62x->dev_desc->sw_num)
949 			continue;
950 
951 		iqs62x->sw_num = info.sw_num;
952 		iqs62x->hw_num = info.hw_num;
953 
954 		/*
955 		 * Read each of the device's designated calibration registers,
956 		 * if any, and exit from the inner loop early if any are equal
957 		 * to zero (indicating the device is uncalibrated). This could
958 		 * be acceptable depending on the device (e.g. IQS620A instead
959 		 * of IQS620AT).
960 		 */
961 		for (j = 0; j < iqs62x->dev_desc->num_cal_regs; j++) {
962 			ret = regmap_read(iqs62x->regmap,
963 					  iqs62x->dev_desc->cal_regs[j], &val);
964 			if (ret)
965 				return ret;
966 
967 			if (!val)
968 				break;
969 		}
970 
971 		/*
972 		 * If the number of nonzero values read from the device equals
973 		 * the number of designated calibration registers (which could
974 		 * be zero), exit from the outer loop early to signal that the
975 		 * device's product and software numbers match a known device,
976 		 * and the device is calibrated (if applicable).
977 		 */
978 		if (j == iqs62x->dev_desc->num_cal_regs)
979 			break;
980 	}
981 
982 	if (!iqs62x->dev_desc) {
983 		dev_err(&client->dev, "Unrecognized product number: 0x%02X\n",
984 			info.prod_num);
985 		return -EINVAL;
986 	}
987 
988 	if (!iqs62x->sw_num) {
989 		dev_err(&client->dev, "Unrecognized software number: 0x%02X\n",
990 			info.sw_num);
991 		return -EINVAL;
992 	}
993 
994 	if (i == ARRAY_SIZE(iqs62x_devs)) {
995 		dev_err(&client->dev, "Uncalibrated device\n");
996 		return -ENODATA;
997 	}
998 
999 	device_property_read_string(&client->dev, "firmware-name", &fw_name);
1000 
1001 	ret = request_firmware_nowait(THIS_MODULE, FW_ACTION_UEVENT,
1002 				      fw_name ? : iqs62x->dev_desc->fw_name,
1003 				      &client->dev, GFP_KERNEL, iqs62x,
1004 				      iqs62x_firmware_load);
1005 	if (ret)
1006 		dev_err(&client->dev, "Failed to request firmware: %d\n", ret);
1007 
1008 	return ret;
1009 }
1010 
1011 static int iqs62x_remove(struct i2c_client *client)
1012 {
1013 	struct iqs62x_core *iqs62x = i2c_get_clientdata(client);
1014 
1015 	wait_for_completion(&iqs62x->fw_done);
1016 
1017 	return 0;
1018 }
1019 
1020 static int __maybe_unused iqs62x_suspend(struct device *dev)
1021 {
1022 	struct iqs62x_core *iqs62x = dev_get_drvdata(dev);
1023 	int ret;
1024 
1025 	wait_for_completion(&iqs62x->fw_done);
1026 
1027 	/*
1028 	 * As per the datasheet, automatic mode switching must be disabled
1029 	 * before the device is placed in or taken out of halt mode.
1030 	 */
1031 	ret = regmap_update_bits(iqs62x->regmap, IQS62X_PWR_SETTINGS,
1032 				 IQS62X_PWR_SETTINGS_DIS_AUTO, 0xFF);
1033 	if (ret)
1034 		return ret;
1035 
1036 	return regmap_update_bits(iqs62x->regmap, IQS62X_PWR_SETTINGS,
1037 				  IQS62X_PWR_SETTINGS_PWR_MODE_MASK,
1038 				  IQS62X_PWR_SETTINGS_PWR_MODE_HALT);
1039 }
1040 
1041 static int __maybe_unused iqs62x_resume(struct device *dev)
1042 {
1043 	struct iqs62x_core *iqs62x = dev_get_drvdata(dev);
1044 	int ret;
1045 
1046 	ret = regmap_update_bits(iqs62x->regmap, IQS62X_PWR_SETTINGS,
1047 				 IQS62X_PWR_SETTINGS_PWR_MODE_MASK,
1048 				 IQS62X_PWR_SETTINGS_PWR_MODE_NORM);
1049 	if (ret)
1050 		return ret;
1051 
1052 	return regmap_update_bits(iqs62x->regmap, IQS62X_PWR_SETTINGS,
1053 				  IQS62X_PWR_SETTINGS_DIS_AUTO, 0);
1054 }
1055 
1056 static SIMPLE_DEV_PM_OPS(iqs62x_pm, iqs62x_suspend, iqs62x_resume);
1057 
1058 static const struct of_device_id iqs62x_of_match[] = {
1059 	{ .compatible = "azoteq,iqs620a" },
1060 	{ .compatible = "azoteq,iqs621" },
1061 	{ .compatible = "azoteq,iqs622" },
1062 	{ .compatible = "azoteq,iqs624" },
1063 	{ .compatible = "azoteq,iqs625" },
1064 	{ }
1065 };
1066 MODULE_DEVICE_TABLE(of, iqs62x_of_match);
1067 
1068 static struct i2c_driver iqs62x_i2c_driver = {
1069 	.driver = {
1070 		.name = "iqs62x",
1071 		.of_match_table = iqs62x_of_match,
1072 		.pm = &iqs62x_pm,
1073 	},
1074 	.probe_new = iqs62x_probe,
1075 	.remove = iqs62x_remove,
1076 };
1077 module_i2c_driver(iqs62x_i2c_driver);
1078 
1079 MODULE_AUTHOR("Jeff LaBundy <jeff@labundy.com>");
1080 MODULE_DESCRIPTION("Azoteq IQS620A/621/622/624/625 Multi-Function Sensors");
1081 MODULE_LICENSE("GPL");
1082