xref: /openbmc/linux/drivers/hwmon/mr75203.c (revision b7b3c35e)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2020 MaxLinear, Inc.
4  *
5  * This driver is a hardware monitoring driver for PVT controller
6  * (MR75203) which is used to configure & control Moortec embedded
7  * analog IP to enable multiple embedded temperature sensor(TS),
8  * voltage monitor(VM) & process detector(PD) modules.
9  */
10 #include <linux/bits.h>
11 #include <linux/clk.h>
12 #include <linux/hwmon.h>
13 #include <linux/module.h>
14 #include <linux/mod_devicetable.h>
15 #include <linux/mutex.h>
16 #include <linux/platform_device.h>
17 #include <linux/property.h>
18 #include <linux/regmap.h>
19 #include <linux/reset.h>
20 #include <linux/units.h>
21 
22 /* PVT Common register */
23 #define PVT_IP_CONFIG	0x04
24 #define TS_NUM_MSK	GENMASK(4, 0)
25 #define TS_NUM_SFT	0
26 #define PD_NUM_MSK	GENMASK(12, 8)
27 #define PD_NUM_SFT	8
28 #define VM_NUM_MSK	GENMASK(20, 16)
29 #define VM_NUM_SFT	16
30 #define CH_NUM_MSK	GENMASK(31, 24)
31 #define CH_NUM_SFT	24
32 
33 /* Macro Common Register */
34 #define CLK_SYNTH		0x00
35 #define CLK_SYNTH_LO_SFT	0
36 #define CLK_SYNTH_HI_SFT	8
37 #define CLK_SYNTH_HOLD_SFT	16
38 #define CLK_SYNTH_EN		BIT(24)
39 #define CLK_SYS_CYCLES_MAX	514
40 #define CLK_SYS_CYCLES_MIN	2
41 
42 #define SDIF_DISABLE	0x04
43 
44 #define SDIF_STAT	0x08
45 #define SDIF_BUSY	BIT(0)
46 #define SDIF_LOCK	BIT(1)
47 
48 #define SDIF_W		0x0c
49 #define SDIF_PROG	BIT(31)
50 #define SDIF_WRN_W	BIT(27)
51 #define SDIF_WRN_R	0x00
52 #define SDIF_ADDR_SFT	24
53 
54 #define SDIF_HALT	0x10
55 #define SDIF_CTRL	0x14
56 #define SDIF_SMPL_CTRL	0x20
57 
58 /* TS & PD Individual Macro Register */
59 #define COM_REG_SIZE	0x40
60 
61 #define SDIF_DONE(n)	(COM_REG_SIZE + 0x14 + 0x40 * (n))
62 #define SDIF_SMPL_DONE	BIT(0)
63 
64 #define SDIF_DATA(n)	(COM_REG_SIZE + 0x18 + 0x40 * (n))
65 #define SAMPLE_DATA_MSK	GENMASK(15, 0)
66 
67 #define HILO_RESET(n)	(COM_REG_SIZE + 0x2c + 0x40 * (n))
68 
69 /* VM Individual Macro Register */
70 #define VM_COM_REG_SIZE	0x200
71 #define VM_SDIF_DONE(n)	(VM_COM_REG_SIZE + 0x34 + 0x200 * (n))
72 #define VM_SDIF_DATA(n)	(VM_COM_REG_SIZE + 0x40 + 0x200 * (n))
73 
74 /* SDA Slave Register */
75 #define IP_CTRL			0x00
76 #define IP_RST_REL		BIT(1)
77 #define IP_RUN_CONT		BIT(3)
78 #define IP_AUTO			BIT(8)
79 #define IP_VM_MODE		BIT(10)
80 
81 #define IP_CFG			0x01
82 #define CFG0_MODE_2		BIT(0)
83 #define CFG0_PARALLEL_OUT	0
84 #define CFG0_12_BIT		0
85 #define CFG1_VOL_MEAS_MODE	0
86 #define CFG1_PARALLEL_OUT	0
87 #define CFG1_14_BIT		0
88 
89 #define IP_DATA		0x03
90 
91 #define IP_POLL		0x04
92 #define VM_CH_INIT	BIT(20)
93 #define VM_CH_REQ	BIT(21)
94 
95 #define IP_TMR			0x05
96 #define POWER_DELAY_CYCLE_256	0x100
97 #define POWER_DELAY_CYCLE_64	0x40
98 
99 #define PVT_POLL_DELAY_US	20
100 #define PVT_POLL_TIMEOUT_US	20000
101 #define PVT_H_CONST		100000
102 #define PVT_CAL5_CONST		2047
103 #define PVT_G_CONST		40000
104 #define PVT_CONV_BITS		10
105 #define PVT_N_CONST		90
106 #define PVT_R_CONST		245805
107 
108 struct pvt_device {
109 	struct regmap		*c_map;
110 	struct regmap		*t_map;
111 	struct regmap		*p_map;
112 	struct regmap		*v_map;
113 	struct clk		*clk;
114 	struct reset_control	*rst;
115 	u32			t_num;
116 	u32			p_num;
117 	u32			v_num;
118 	u32			ip_freq;
119 	u8			*vm_idx;
120 };
121 
122 static umode_t pvt_is_visible(const void *data, enum hwmon_sensor_types type,
123 			      u32 attr, int channel)
124 {
125 	switch (type) {
126 	case hwmon_temp:
127 		if (attr == hwmon_temp_input)
128 			return 0444;
129 		break;
130 	case hwmon_in:
131 		if (attr == hwmon_in_input)
132 			return 0444;
133 		break;
134 	default:
135 		break;
136 	}
137 	return 0;
138 }
139 
140 static int pvt_read_temp(struct device *dev, u32 attr, int channel, long *val)
141 {
142 	struct pvt_device *pvt = dev_get_drvdata(dev);
143 	struct regmap *t_map = pvt->t_map;
144 	u32 stat, nbs;
145 	int ret;
146 	u64 tmp;
147 
148 	switch (attr) {
149 	case hwmon_temp_input:
150 		ret = regmap_read_poll_timeout(t_map, SDIF_DONE(channel),
151 					       stat, stat & SDIF_SMPL_DONE,
152 					       PVT_POLL_DELAY_US,
153 					       PVT_POLL_TIMEOUT_US);
154 		if (ret)
155 			return ret;
156 
157 		ret = regmap_read(t_map, SDIF_DATA(channel), &nbs);
158 		if(ret < 0)
159 			return ret;
160 
161 		nbs &= SAMPLE_DATA_MSK;
162 
163 		/*
164 		 * Convert the register value to
165 		 * degrees centigrade temperature
166 		 */
167 		tmp = nbs * PVT_H_CONST;
168 		do_div(tmp, PVT_CAL5_CONST);
169 		*val = tmp - PVT_G_CONST - pvt->ip_freq;
170 
171 		return 0;
172 	default:
173 		return -EOPNOTSUPP;
174 	}
175 }
176 
177 static int pvt_read_in(struct device *dev, u32 attr, int channel, long *val)
178 {
179 	struct pvt_device *pvt = dev_get_drvdata(dev);
180 	struct regmap *v_map = pvt->v_map;
181 	u32 n, stat;
182 	u8 vm_idx;
183 	int ret;
184 
185 	if (channel >= pvt->v_num)
186 		return -EINVAL;
187 
188 	vm_idx = pvt->vm_idx[channel];
189 
190 	switch (attr) {
191 	case hwmon_in_input:
192 		ret = regmap_read_poll_timeout(v_map, VM_SDIF_DONE(vm_idx),
193 					       stat, stat & SDIF_SMPL_DONE,
194 					       PVT_POLL_DELAY_US,
195 					       PVT_POLL_TIMEOUT_US);
196 		if (ret)
197 			return ret;
198 
199 		ret = regmap_read(v_map, VM_SDIF_DATA(vm_idx), &n);
200 		if(ret < 0)
201 			return ret;
202 
203 		n &= SAMPLE_DATA_MSK;
204 		/* Convert the N bitstream count into voltage */
205 		*val = (PVT_N_CONST * n - PVT_R_CONST) >> PVT_CONV_BITS;
206 
207 		return 0;
208 	default:
209 		return -EOPNOTSUPP;
210 	}
211 }
212 
213 static int pvt_read(struct device *dev, enum hwmon_sensor_types type,
214 		    u32 attr, int channel, long *val)
215 {
216 	switch (type) {
217 	case hwmon_temp:
218 		return pvt_read_temp(dev, attr, channel, val);
219 	case hwmon_in:
220 		return pvt_read_in(dev, attr, channel, val);
221 	default:
222 		return -EOPNOTSUPP;
223 	}
224 }
225 
226 static const u32 pvt_chip_config[] = {
227 	HWMON_C_REGISTER_TZ,
228 	0
229 };
230 
231 static const struct hwmon_channel_info pvt_chip = {
232 	.type = hwmon_chip,
233 	.config = pvt_chip_config,
234 };
235 
236 static struct hwmon_channel_info pvt_temp = {
237 	.type = hwmon_temp,
238 };
239 
240 static struct hwmon_channel_info pvt_in = {
241 	.type = hwmon_in,
242 };
243 
244 static const struct hwmon_ops pvt_hwmon_ops = {
245 	.is_visible = pvt_is_visible,
246 	.read = pvt_read,
247 };
248 
249 static struct hwmon_chip_info pvt_chip_info = {
250 	.ops = &pvt_hwmon_ops,
251 };
252 
253 static int pvt_init(struct pvt_device *pvt)
254 {
255 	u16 sys_freq, key, middle, low = 4, high = 8;
256 	struct regmap *t_map = pvt->t_map;
257 	struct regmap *p_map = pvt->p_map;
258 	struct regmap *v_map = pvt->v_map;
259 	u32 t_num = pvt->t_num;
260 	u32 p_num = pvt->p_num;
261 	u32 v_num = pvt->v_num;
262 	u32 clk_synth, val;
263 	int ret;
264 
265 	sys_freq = clk_get_rate(pvt->clk) / HZ_PER_MHZ;
266 	while (high >= low) {
267 		middle = (low + high + 1) / 2;
268 		key = DIV_ROUND_CLOSEST(sys_freq, middle);
269 		if (key > CLK_SYS_CYCLES_MAX) {
270 			low = middle + 1;
271 			continue;
272 		} else if (key < CLK_SYS_CYCLES_MIN) {
273 			high = middle - 1;
274 			continue;
275 		} else {
276 			break;
277 		}
278 	}
279 
280 	/*
281 	 * The system supports 'clk_sys' to 'clk_ip' frequency ratios
282 	 * from 2:1 to 512:1
283 	 */
284 	key = clamp_val(key, CLK_SYS_CYCLES_MIN, CLK_SYS_CYCLES_MAX) - 2;
285 
286 	clk_synth = ((key + 1) >> 1) << CLK_SYNTH_LO_SFT |
287 		    (key >> 1) << CLK_SYNTH_HI_SFT |
288 		    (key >> 1) << CLK_SYNTH_HOLD_SFT | CLK_SYNTH_EN;
289 
290 	pvt->ip_freq = sys_freq * 100 / (key + 2);
291 
292 	if (t_num) {
293 		ret = regmap_write(t_map, SDIF_SMPL_CTRL, 0x0);
294 		if(ret < 0)
295 			return ret;
296 
297 		ret = regmap_write(t_map, SDIF_HALT, 0x0);
298 		if(ret < 0)
299 			return ret;
300 
301 		ret = regmap_write(t_map, CLK_SYNTH, clk_synth);
302 		if(ret < 0)
303 			return ret;
304 
305 		ret = regmap_write(t_map, SDIF_DISABLE, 0x0);
306 		if(ret < 0)
307 			return ret;
308 
309 		ret = regmap_read_poll_timeout(t_map, SDIF_STAT,
310 					       val, !(val & SDIF_BUSY),
311 					       PVT_POLL_DELAY_US,
312 					       PVT_POLL_TIMEOUT_US);
313 		if (ret)
314 			return ret;
315 
316 		val = CFG0_MODE_2 | CFG0_PARALLEL_OUT | CFG0_12_BIT |
317 		      IP_CFG << SDIF_ADDR_SFT | SDIF_WRN_W | SDIF_PROG;
318 		ret = regmap_write(t_map, SDIF_W, val);
319 		if(ret < 0)
320 			return ret;
321 
322 		ret = regmap_read_poll_timeout(t_map, SDIF_STAT,
323 					       val, !(val & SDIF_BUSY),
324 					       PVT_POLL_DELAY_US,
325 					       PVT_POLL_TIMEOUT_US);
326 		if (ret)
327 			return ret;
328 
329 		val = POWER_DELAY_CYCLE_256 | IP_TMR << SDIF_ADDR_SFT |
330 			      SDIF_WRN_W | SDIF_PROG;
331 		ret = regmap_write(t_map, SDIF_W, val);
332 		if(ret < 0)
333 			return ret;
334 
335 		ret = regmap_read_poll_timeout(t_map, SDIF_STAT,
336 					       val, !(val & SDIF_BUSY),
337 					       PVT_POLL_DELAY_US,
338 					       PVT_POLL_TIMEOUT_US);
339 		if (ret)
340 			return ret;
341 
342 		val = IP_RST_REL | IP_RUN_CONT | IP_AUTO |
343 		      IP_CTRL << SDIF_ADDR_SFT |
344 		      SDIF_WRN_W | SDIF_PROG;
345 		ret = regmap_write(t_map, SDIF_W, val);
346 		if(ret < 0)
347 			return ret;
348 	}
349 
350 	if (p_num) {
351 		ret = regmap_write(p_map, SDIF_HALT, 0x0);
352 		if(ret < 0)
353 			return ret;
354 
355 		ret = regmap_write(p_map, SDIF_DISABLE, BIT(p_num) - 1);
356 		if(ret < 0)
357 			return ret;
358 
359 		ret = regmap_write(p_map, CLK_SYNTH, clk_synth);
360 		if(ret < 0)
361 			return ret;
362 	}
363 
364 	if (v_num) {
365 		ret = regmap_write(v_map, SDIF_SMPL_CTRL, 0x0);
366 		if(ret < 0)
367 			return ret;
368 
369 		ret = regmap_write(v_map, SDIF_HALT, 0x0);
370 		if(ret < 0)
371 			return ret;
372 
373 		ret = regmap_write(v_map, CLK_SYNTH, clk_synth);
374 		if(ret < 0)
375 			return ret;
376 
377 		ret = regmap_write(v_map, SDIF_DISABLE, 0x0);
378 		if(ret < 0)
379 			return ret;
380 
381 		ret = regmap_read_poll_timeout(v_map, SDIF_STAT,
382 					       val, !(val & SDIF_BUSY),
383 					       PVT_POLL_DELAY_US,
384 					       PVT_POLL_TIMEOUT_US);
385 		if (ret)
386 			return ret;
387 
388 		val = CFG1_VOL_MEAS_MODE | CFG1_PARALLEL_OUT |
389 		      CFG1_14_BIT | IP_CFG << SDIF_ADDR_SFT |
390 		      SDIF_WRN_W | SDIF_PROG;
391 		ret = regmap_write(v_map, SDIF_W, val);
392 		if(ret < 0)
393 			return ret;
394 
395 		ret = regmap_read_poll_timeout(v_map, SDIF_STAT,
396 					       val, !(val & SDIF_BUSY),
397 					       PVT_POLL_DELAY_US,
398 					       PVT_POLL_TIMEOUT_US);
399 		if (ret)
400 			return ret;
401 
402 		val = POWER_DELAY_CYCLE_64 | IP_TMR << SDIF_ADDR_SFT |
403 		      SDIF_WRN_W | SDIF_PROG;
404 		ret = regmap_write(v_map, SDIF_W, val);
405 		if(ret < 0)
406 			return ret;
407 
408 		ret = regmap_read_poll_timeout(v_map, SDIF_STAT,
409 					       val, !(val & SDIF_BUSY),
410 					       PVT_POLL_DELAY_US,
411 					       PVT_POLL_TIMEOUT_US);
412 		if (ret)
413 			return ret;
414 
415 		val = IP_RST_REL | IP_RUN_CONT | IP_AUTO | IP_VM_MODE |
416 		      IP_CTRL << SDIF_ADDR_SFT |
417 		      SDIF_WRN_W | SDIF_PROG;
418 		ret = regmap_write(v_map, SDIF_W, val);
419 		if(ret < 0)
420 			return ret;
421 	}
422 
423 	return 0;
424 }
425 
426 static struct regmap_config pvt_regmap_config = {
427 	.reg_bits = 32,
428 	.reg_stride = 4,
429 	.val_bits = 32,
430 };
431 
432 static int pvt_get_regmap(struct platform_device *pdev, char *reg_name,
433 			  struct pvt_device *pvt)
434 {
435 	struct device *dev = &pdev->dev;
436 	struct regmap **reg_map;
437 	void __iomem *io_base;
438 
439 	if (!strcmp(reg_name, "common"))
440 		reg_map = &pvt->c_map;
441 	else if (!strcmp(reg_name, "ts"))
442 		reg_map = &pvt->t_map;
443 	else if (!strcmp(reg_name, "pd"))
444 		reg_map = &pvt->p_map;
445 	else if (!strcmp(reg_name, "vm"))
446 		reg_map = &pvt->v_map;
447 	else
448 		return -EINVAL;
449 
450 	io_base = devm_platform_ioremap_resource_byname(pdev, reg_name);
451 	if (IS_ERR(io_base))
452 		return PTR_ERR(io_base);
453 
454 	pvt_regmap_config.name = reg_name;
455 	*reg_map = devm_regmap_init_mmio(dev, io_base, &pvt_regmap_config);
456 	if (IS_ERR(*reg_map)) {
457 		dev_err(dev, "failed to init register map\n");
458 		return PTR_ERR(*reg_map);
459 	}
460 
461 	return 0;
462 }
463 
464 static void pvt_clk_disable(void *data)
465 {
466 	struct pvt_device *pvt = data;
467 
468 	clk_disable_unprepare(pvt->clk);
469 }
470 
471 static int pvt_clk_enable(struct device *dev, struct pvt_device *pvt)
472 {
473 	int ret;
474 
475 	ret = clk_prepare_enable(pvt->clk);
476 	if (ret)
477 		return ret;
478 
479 	return devm_add_action_or_reset(dev, pvt_clk_disable, pvt);
480 }
481 
482 static void pvt_reset_control_assert(void *data)
483 {
484 	struct pvt_device *pvt = data;
485 
486 	reset_control_assert(pvt->rst);
487 }
488 
489 static int pvt_reset_control_deassert(struct device *dev, struct pvt_device *pvt)
490 {
491 	int ret;
492 
493 	ret = reset_control_deassert(pvt->rst);
494 	if (ret)
495 		return ret;
496 
497 	return devm_add_action_or_reset(dev, pvt_reset_control_assert, pvt);
498 }
499 
500 static int mr75203_probe(struct platform_device *pdev)
501 {
502 	const struct hwmon_channel_info **pvt_info;
503 	u32 ts_num, vm_num, pd_num, val, index, i;
504 	struct device *dev = &pdev->dev;
505 	u32 *temp_config, *in_config;
506 	struct device *hwmon_dev;
507 	struct pvt_device *pvt;
508 	int ret;
509 
510 	pvt = devm_kzalloc(dev, sizeof(*pvt), GFP_KERNEL);
511 	if (!pvt)
512 		return -ENOMEM;
513 
514 	ret = pvt_get_regmap(pdev, "common", pvt);
515 	if (ret)
516 		return ret;
517 
518 	pvt->clk = devm_clk_get(dev, NULL);
519 	if (IS_ERR(pvt->clk))
520 		return dev_err_probe(dev, PTR_ERR(pvt->clk), "failed to get clock\n");
521 
522 	ret = pvt_clk_enable(dev, pvt);
523 	if (ret) {
524 		dev_err(dev, "failed to enable clock\n");
525 		return ret;
526 	}
527 
528 	pvt->rst = devm_reset_control_get_exclusive(dev, NULL);
529 	if (IS_ERR(pvt->rst))
530 		return dev_err_probe(dev, PTR_ERR(pvt->rst),
531 				     "failed to get reset control\n");
532 
533 	ret = pvt_reset_control_deassert(dev, pvt);
534 	if (ret)
535 		return dev_err_probe(dev, ret, "cannot deassert reset control\n");
536 
537 	ret = regmap_read(pvt->c_map, PVT_IP_CONFIG, &val);
538 	if(ret < 0)
539 		return ret;
540 
541 	ts_num = (val & TS_NUM_MSK) >> TS_NUM_SFT;
542 	pd_num = (val & PD_NUM_MSK) >> PD_NUM_SFT;
543 	vm_num = (val & VM_NUM_MSK) >> VM_NUM_SFT;
544 	pvt->t_num = ts_num;
545 	pvt->p_num = pd_num;
546 	pvt->v_num = vm_num;
547 	val = 0;
548 	if (ts_num)
549 		val++;
550 	if (vm_num)
551 		val++;
552 	if (!val)
553 		return -ENODEV;
554 
555 	pvt_info = devm_kcalloc(dev, val + 2, sizeof(*pvt_info), GFP_KERNEL);
556 	if (!pvt_info)
557 		return -ENOMEM;
558 	pvt_info[0] = &pvt_chip;
559 	index = 1;
560 
561 	if (ts_num) {
562 		ret = pvt_get_regmap(pdev, "ts", pvt);
563 		if (ret)
564 			return ret;
565 
566 		temp_config = devm_kcalloc(dev, ts_num + 1,
567 					   sizeof(*temp_config), GFP_KERNEL);
568 		if (!temp_config)
569 			return -ENOMEM;
570 
571 		memset32(temp_config, HWMON_T_INPUT, ts_num);
572 		pvt_temp.config = temp_config;
573 		pvt_info[index++] = &pvt_temp;
574 	}
575 
576 	if (pd_num) {
577 		ret = pvt_get_regmap(pdev, "pd", pvt);
578 		if (ret)
579 			return ret;
580 	}
581 
582 	if (vm_num) {
583 		u32 num = vm_num;
584 
585 		ret = pvt_get_regmap(pdev, "vm", pvt);
586 		if (ret)
587 			return ret;
588 
589 		pvt->vm_idx = devm_kcalloc(dev, vm_num, sizeof(*pvt->vm_idx),
590 					   GFP_KERNEL);
591 		if (!pvt->vm_idx)
592 			return -ENOMEM;
593 
594 		ret = device_property_read_u8_array(dev, "intel,vm-map",
595 						    pvt->vm_idx, vm_num);
596 		if (ret) {
597 			num = 0;
598 		} else {
599 			for (i = 0; i < vm_num; i++)
600 				if (pvt->vm_idx[i] >= vm_num ||
601 				    pvt->vm_idx[i] == 0xff) {
602 					num = i;
603 					break;
604 				}
605 		}
606 
607 		/*
608 		 * Incase intel,vm-map property is not defined, we assume
609 		 * incremental channel numbers.
610 		 */
611 		for (i = num; i < vm_num; i++)
612 			pvt->vm_idx[i] = i;
613 
614 		in_config = devm_kcalloc(dev, num + 1,
615 					 sizeof(*in_config), GFP_KERNEL);
616 		if (!in_config)
617 			return -ENOMEM;
618 
619 		memset32(in_config, HWMON_I_INPUT, num);
620 		in_config[num] = 0;
621 		pvt_in.config = in_config;
622 
623 		pvt_info[index++] = &pvt_in;
624 	}
625 
626 	ret = pvt_init(pvt);
627 	if (ret) {
628 		dev_err(dev, "failed to init pvt: %d\n", ret);
629 		return ret;
630 	}
631 
632 	pvt_chip_info.info = pvt_info;
633 	hwmon_dev = devm_hwmon_device_register_with_info(dev, "pvt",
634 							 pvt,
635 							 &pvt_chip_info,
636 							 NULL);
637 
638 	return PTR_ERR_OR_ZERO(hwmon_dev);
639 }
640 
641 static const struct of_device_id moortec_pvt_of_match[] = {
642 	{ .compatible = "moortec,mr75203" },
643 	{ }
644 };
645 MODULE_DEVICE_TABLE(of, moortec_pvt_of_match);
646 
647 static struct platform_driver moortec_pvt_driver = {
648 	.driver = {
649 		.name = "moortec-pvt",
650 		.of_match_table = moortec_pvt_of_match,
651 	},
652 	.probe = mr75203_probe,
653 };
654 module_platform_driver(moortec_pvt_driver);
655 
656 MODULE_LICENSE("GPL v2");
657