xref: /openbmc/linux/drivers/hwmon/mr75203.c (revision 3ce7547e)
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 struct hwmon_channel_info pvt_temp = {
227 	.type = hwmon_temp,
228 };
229 
230 static struct hwmon_channel_info pvt_in = {
231 	.type = hwmon_in,
232 };
233 
234 static const struct hwmon_ops pvt_hwmon_ops = {
235 	.is_visible = pvt_is_visible,
236 	.read = pvt_read,
237 };
238 
239 static struct hwmon_chip_info pvt_chip_info = {
240 	.ops = &pvt_hwmon_ops,
241 };
242 
243 static int pvt_init(struct pvt_device *pvt)
244 {
245 	u16 sys_freq, key, middle, low = 4, high = 8;
246 	struct regmap *t_map = pvt->t_map;
247 	struct regmap *p_map = pvt->p_map;
248 	struct regmap *v_map = pvt->v_map;
249 	u32 t_num = pvt->t_num;
250 	u32 p_num = pvt->p_num;
251 	u32 v_num = pvt->v_num;
252 	u32 clk_synth, val;
253 	int ret;
254 
255 	sys_freq = clk_get_rate(pvt->clk) / HZ_PER_MHZ;
256 	while (high >= low) {
257 		middle = (low + high + 1) / 2;
258 		key = DIV_ROUND_CLOSEST(sys_freq, middle);
259 		if (key > CLK_SYS_CYCLES_MAX) {
260 			low = middle + 1;
261 			continue;
262 		} else if (key < CLK_SYS_CYCLES_MIN) {
263 			high = middle - 1;
264 			continue;
265 		} else {
266 			break;
267 		}
268 	}
269 
270 	/*
271 	 * The system supports 'clk_sys' to 'clk_ip' frequency ratios
272 	 * from 2:1 to 512:1
273 	 */
274 	key = clamp_val(key, CLK_SYS_CYCLES_MIN, CLK_SYS_CYCLES_MAX) - 2;
275 
276 	clk_synth = ((key + 1) >> 1) << CLK_SYNTH_LO_SFT |
277 		    (key >> 1) << CLK_SYNTH_HI_SFT |
278 		    (key >> 1) << CLK_SYNTH_HOLD_SFT | CLK_SYNTH_EN;
279 
280 	pvt->ip_freq = sys_freq * 100 / (key + 2);
281 
282 	if (t_num) {
283 		ret = regmap_write(t_map, SDIF_SMPL_CTRL, 0x0);
284 		if(ret < 0)
285 			return ret;
286 
287 		ret = regmap_write(t_map, SDIF_HALT, 0x0);
288 		if(ret < 0)
289 			return ret;
290 
291 		ret = regmap_write(t_map, CLK_SYNTH, clk_synth);
292 		if(ret < 0)
293 			return ret;
294 
295 		ret = regmap_write(t_map, SDIF_DISABLE, 0x0);
296 		if(ret < 0)
297 			return ret;
298 
299 		ret = regmap_read_poll_timeout(t_map, SDIF_STAT,
300 					       val, !(val & SDIF_BUSY),
301 					       PVT_POLL_DELAY_US,
302 					       PVT_POLL_TIMEOUT_US);
303 		if (ret)
304 			return ret;
305 
306 		val = CFG0_MODE_2 | CFG0_PARALLEL_OUT | CFG0_12_BIT |
307 		      IP_CFG << SDIF_ADDR_SFT | SDIF_WRN_W | SDIF_PROG;
308 		ret = regmap_write(t_map, SDIF_W, val);
309 		if(ret < 0)
310 			return ret;
311 
312 		ret = regmap_read_poll_timeout(t_map, SDIF_STAT,
313 					       val, !(val & SDIF_BUSY),
314 					       PVT_POLL_DELAY_US,
315 					       PVT_POLL_TIMEOUT_US);
316 		if (ret)
317 			return ret;
318 
319 		val = POWER_DELAY_CYCLE_256 | IP_TMR << SDIF_ADDR_SFT |
320 			      SDIF_WRN_W | SDIF_PROG;
321 		ret = regmap_write(t_map, SDIF_W, val);
322 		if(ret < 0)
323 			return ret;
324 
325 		ret = regmap_read_poll_timeout(t_map, SDIF_STAT,
326 					       val, !(val & SDIF_BUSY),
327 					       PVT_POLL_DELAY_US,
328 					       PVT_POLL_TIMEOUT_US);
329 		if (ret)
330 			return ret;
331 
332 		val = IP_RST_REL | IP_RUN_CONT | IP_AUTO |
333 		      IP_CTRL << SDIF_ADDR_SFT |
334 		      SDIF_WRN_W | SDIF_PROG;
335 		ret = regmap_write(t_map, SDIF_W, val);
336 		if(ret < 0)
337 			return ret;
338 	}
339 
340 	if (p_num) {
341 		ret = regmap_write(p_map, SDIF_HALT, 0x0);
342 		if(ret < 0)
343 			return ret;
344 
345 		ret = regmap_write(p_map, SDIF_DISABLE, BIT(p_num) - 1);
346 		if(ret < 0)
347 			return ret;
348 
349 		ret = regmap_write(p_map, CLK_SYNTH, clk_synth);
350 		if(ret < 0)
351 			return ret;
352 	}
353 
354 	if (v_num) {
355 		ret = regmap_write(v_map, SDIF_SMPL_CTRL, 0x0);
356 		if(ret < 0)
357 			return ret;
358 
359 		ret = regmap_write(v_map, SDIF_HALT, 0x0);
360 		if(ret < 0)
361 			return ret;
362 
363 		ret = regmap_write(v_map, CLK_SYNTH, clk_synth);
364 		if(ret < 0)
365 			return ret;
366 
367 		ret = regmap_write(v_map, SDIF_DISABLE, 0x0);
368 		if(ret < 0)
369 			return ret;
370 
371 		ret = regmap_read_poll_timeout(v_map, SDIF_STAT,
372 					       val, !(val & SDIF_BUSY),
373 					       PVT_POLL_DELAY_US,
374 					       PVT_POLL_TIMEOUT_US);
375 		if (ret)
376 			return ret;
377 
378 		val = CFG1_VOL_MEAS_MODE | CFG1_PARALLEL_OUT |
379 		      CFG1_14_BIT | IP_CFG << SDIF_ADDR_SFT |
380 		      SDIF_WRN_W | SDIF_PROG;
381 		ret = regmap_write(v_map, SDIF_W, val);
382 		if(ret < 0)
383 			return ret;
384 
385 		ret = regmap_read_poll_timeout(v_map, SDIF_STAT,
386 					       val, !(val & SDIF_BUSY),
387 					       PVT_POLL_DELAY_US,
388 					       PVT_POLL_TIMEOUT_US);
389 		if (ret)
390 			return ret;
391 
392 		val = POWER_DELAY_CYCLE_64 | IP_TMR << SDIF_ADDR_SFT |
393 		      SDIF_WRN_W | SDIF_PROG;
394 		ret = regmap_write(v_map, SDIF_W, val);
395 		if(ret < 0)
396 			return ret;
397 
398 		ret = regmap_read_poll_timeout(v_map, SDIF_STAT,
399 					       val, !(val & SDIF_BUSY),
400 					       PVT_POLL_DELAY_US,
401 					       PVT_POLL_TIMEOUT_US);
402 		if (ret)
403 			return ret;
404 
405 		val = IP_RST_REL | IP_RUN_CONT | IP_AUTO | IP_VM_MODE |
406 		      IP_CTRL << SDIF_ADDR_SFT |
407 		      SDIF_WRN_W | SDIF_PROG;
408 		ret = regmap_write(v_map, SDIF_W, val);
409 		if(ret < 0)
410 			return ret;
411 	}
412 
413 	return 0;
414 }
415 
416 static struct regmap_config pvt_regmap_config = {
417 	.reg_bits = 32,
418 	.reg_stride = 4,
419 	.val_bits = 32,
420 };
421 
422 static int pvt_get_regmap(struct platform_device *pdev, char *reg_name,
423 			  struct pvt_device *pvt)
424 {
425 	struct device *dev = &pdev->dev;
426 	struct regmap **reg_map;
427 	void __iomem *io_base;
428 
429 	if (!strcmp(reg_name, "common"))
430 		reg_map = &pvt->c_map;
431 	else if (!strcmp(reg_name, "ts"))
432 		reg_map = &pvt->t_map;
433 	else if (!strcmp(reg_name, "pd"))
434 		reg_map = &pvt->p_map;
435 	else if (!strcmp(reg_name, "vm"))
436 		reg_map = &pvt->v_map;
437 	else
438 		return -EINVAL;
439 
440 	io_base = devm_platform_ioremap_resource_byname(pdev, reg_name);
441 	if (IS_ERR(io_base))
442 		return PTR_ERR(io_base);
443 
444 	pvt_regmap_config.name = reg_name;
445 	*reg_map = devm_regmap_init_mmio(dev, io_base, &pvt_regmap_config);
446 	if (IS_ERR(*reg_map)) {
447 		dev_err(dev, "failed to init register map\n");
448 		return PTR_ERR(*reg_map);
449 	}
450 
451 	return 0;
452 }
453 
454 static void pvt_clk_disable(void *data)
455 {
456 	struct pvt_device *pvt = data;
457 
458 	clk_disable_unprepare(pvt->clk);
459 }
460 
461 static int pvt_clk_enable(struct device *dev, struct pvt_device *pvt)
462 {
463 	int ret;
464 
465 	ret = clk_prepare_enable(pvt->clk);
466 	if (ret)
467 		return ret;
468 
469 	return devm_add_action_or_reset(dev, pvt_clk_disable, pvt);
470 }
471 
472 static void pvt_reset_control_assert(void *data)
473 {
474 	struct pvt_device *pvt = data;
475 
476 	reset_control_assert(pvt->rst);
477 }
478 
479 static int pvt_reset_control_deassert(struct device *dev, struct pvt_device *pvt)
480 {
481 	int ret;
482 
483 	ret = reset_control_deassert(pvt->rst);
484 	if (ret)
485 		return ret;
486 
487 	return devm_add_action_or_reset(dev, pvt_reset_control_assert, pvt);
488 }
489 
490 static int mr75203_probe(struct platform_device *pdev)
491 {
492 	const struct hwmon_channel_info **pvt_info;
493 	u32 ts_num, vm_num, pd_num, val, index, i;
494 	struct device *dev = &pdev->dev;
495 	u32 *temp_config, *in_config;
496 	struct device *hwmon_dev;
497 	struct pvt_device *pvt;
498 	int ret;
499 
500 	pvt = devm_kzalloc(dev, sizeof(*pvt), GFP_KERNEL);
501 	if (!pvt)
502 		return -ENOMEM;
503 
504 	ret = pvt_get_regmap(pdev, "common", pvt);
505 	if (ret)
506 		return ret;
507 
508 	pvt->clk = devm_clk_get(dev, NULL);
509 	if (IS_ERR(pvt->clk))
510 		return dev_err_probe(dev, PTR_ERR(pvt->clk), "failed to get clock\n");
511 
512 	ret = pvt_clk_enable(dev, pvt);
513 	if (ret) {
514 		dev_err(dev, "failed to enable clock\n");
515 		return ret;
516 	}
517 
518 	pvt->rst = devm_reset_control_get_exclusive(dev, NULL);
519 	if (IS_ERR(pvt->rst))
520 		return dev_err_probe(dev, PTR_ERR(pvt->rst),
521 				     "failed to get reset control\n");
522 
523 	ret = pvt_reset_control_deassert(dev, pvt);
524 	if (ret)
525 		return dev_err_probe(dev, ret, "cannot deassert reset control\n");
526 
527 	ret = regmap_read(pvt->c_map, PVT_IP_CONFIG, &val);
528 	if(ret < 0)
529 		return ret;
530 
531 	ts_num = (val & TS_NUM_MSK) >> TS_NUM_SFT;
532 	pd_num = (val & PD_NUM_MSK) >> PD_NUM_SFT;
533 	vm_num = (val & VM_NUM_MSK) >> VM_NUM_SFT;
534 	pvt->t_num = ts_num;
535 	pvt->p_num = pd_num;
536 	pvt->v_num = vm_num;
537 	val = 0;
538 	if (ts_num)
539 		val++;
540 	if (vm_num)
541 		val++;
542 	if (!val)
543 		return -ENODEV;
544 
545 	pvt_info = devm_kcalloc(dev, val + 2, sizeof(*pvt_info), GFP_KERNEL);
546 	if (!pvt_info)
547 		return -ENOMEM;
548 	pvt_info[0] = HWMON_CHANNEL_INFO(chip, HWMON_C_REGISTER_TZ);
549 	index = 1;
550 
551 	if (ts_num) {
552 		ret = pvt_get_regmap(pdev, "ts", pvt);
553 		if (ret)
554 			return ret;
555 
556 		temp_config = devm_kcalloc(dev, ts_num + 1,
557 					   sizeof(*temp_config), GFP_KERNEL);
558 		if (!temp_config)
559 			return -ENOMEM;
560 
561 		memset32(temp_config, HWMON_T_INPUT, ts_num);
562 		pvt_temp.config = temp_config;
563 		pvt_info[index++] = &pvt_temp;
564 	}
565 
566 	if (pd_num) {
567 		ret = pvt_get_regmap(pdev, "pd", pvt);
568 		if (ret)
569 			return ret;
570 	}
571 
572 	if (vm_num) {
573 		u32 num = vm_num;
574 
575 		ret = pvt_get_regmap(pdev, "vm", pvt);
576 		if (ret)
577 			return ret;
578 
579 		pvt->vm_idx = devm_kcalloc(dev, vm_num, sizeof(*pvt->vm_idx),
580 					   GFP_KERNEL);
581 		if (!pvt->vm_idx)
582 			return -ENOMEM;
583 
584 		ret = device_property_read_u8_array(dev, "intel,vm-map",
585 						    pvt->vm_idx, vm_num);
586 		if (ret) {
587 			num = 0;
588 		} else {
589 			for (i = 0; i < vm_num; i++)
590 				if (pvt->vm_idx[i] >= vm_num ||
591 				    pvt->vm_idx[i] == 0xff) {
592 					num = i;
593 					break;
594 				}
595 		}
596 
597 		/*
598 		 * Incase intel,vm-map property is not defined, we assume
599 		 * incremental channel numbers.
600 		 */
601 		for (i = num; i < vm_num; i++)
602 			pvt->vm_idx[i] = i;
603 
604 		in_config = devm_kcalloc(dev, num + 1,
605 					 sizeof(*in_config), GFP_KERNEL);
606 		if (!in_config)
607 			return -ENOMEM;
608 
609 		memset32(in_config, HWMON_I_INPUT, num);
610 		in_config[num] = 0;
611 		pvt_in.config = in_config;
612 
613 		pvt_info[index++] = &pvt_in;
614 	}
615 
616 	ret = pvt_init(pvt);
617 	if (ret) {
618 		dev_err(dev, "failed to init pvt: %d\n", ret);
619 		return ret;
620 	}
621 
622 	pvt_chip_info.info = pvt_info;
623 	hwmon_dev = devm_hwmon_device_register_with_info(dev, "pvt",
624 							 pvt,
625 							 &pvt_chip_info,
626 							 NULL);
627 
628 	return PTR_ERR_OR_ZERO(hwmon_dev);
629 }
630 
631 static const struct of_device_id moortec_pvt_of_match[] = {
632 	{ .compatible = "moortec,mr75203" },
633 	{ }
634 };
635 MODULE_DEVICE_TABLE(of, moortec_pvt_of_match);
636 
637 static struct platform_driver moortec_pvt_driver = {
638 	.driver = {
639 		.name = "moortec-pvt",
640 		.of_match_table = moortec_pvt_of_match,
641 	},
642 	.probe = mr75203_probe,
643 };
644 module_platform_driver(moortec_pvt_driver);
645 
646 MODULE_LICENSE("GPL v2");
647