summaryrefslogtreecommitdiffstats
path: root/drivers/hwmon/gsc-hwmon.c
blob: d64be48f1ef6c51c2490ee633824440b068f00b3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
// SPDX-License-Identifier: GPL-2.0
/*
 * Driver for Gateworks System Controller Hardware Monitor module
 *
 * Copyright (C) 2020 Gateworks Corporation
 */
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/mfd/gsc.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/slab.h>

#include <linux/platform_data/gsc_hwmon.h>

#define GSC_HWMON_MAX_TEMP_CH	16
#define GSC_HWMON_MAX_IN_CH	16
#define GSC_HWMON_MAX_FAN_CH	16

#define GSC_HWMON_RESOLUTION	12
#define GSC_HWMON_VREF		2500

struct gsc_hwmon_data {
	struct gsc_dev *gsc;
	struct gsc_hwmon_platform_data *pdata;
	struct regmap *regmap;
	const struct gsc_hwmon_channel *temp_ch[GSC_HWMON_MAX_TEMP_CH];
	const struct gsc_hwmon_channel *in_ch[GSC_HWMON_MAX_IN_CH];
	const struct gsc_hwmon_channel *fan_ch[GSC_HWMON_MAX_FAN_CH];
	u32 temp_config[GSC_HWMON_MAX_TEMP_CH + 1];
	u32 in_config[GSC_HWMON_MAX_IN_CH + 1];
	u32 fan_config[GSC_HWMON_MAX_FAN_CH + 1];
	struct hwmon_channel_info temp_info;
	struct hwmon_channel_info in_info;
	struct hwmon_channel_info fan_info;
	const struct hwmon_channel_info *info[4];
	struct hwmon_chip_info chip;
};

static struct regmap_bus gsc_hwmon_regmap_bus = {
	.reg_read = gsc_read,
	.reg_write = gsc_write,
};

static const struct regmap_config gsc_hwmon_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
	.cache_type = REGCACHE_NONE,
};

static ssize_t pwm_auto_point_temp_show(struct device *dev,
					struct device_attribute *devattr,
					char *buf)
{
	struct gsc_hwmon_data *hwmon = dev_get_drvdata(dev);
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
	u8 reg = hwmon->pdata->fan_base + (2 * attr->index);
	u8 regs[2];
	int ret;

	ret = regmap_bulk_read(hwmon->regmap, reg, regs, 2);
	if (ret)
		return ret;

	ret = regs[0] | regs[1] << 8;
	return sprintf(buf, "%d\n", ret * 10);
}

static ssize_t pwm_auto_point_temp_store(struct device *dev,
					 struct device_attribute *devattr,
					 const char *buf, size_t count)
{
	struct gsc_hwmon_data *hwmon = dev_get_drvdata(dev);
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
	u8 reg = hwmon->pdata->fan_base + (2 * attr->index);
	u8 regs[2];
	long temp;
	int err;

	if (kstrtol(buf, 10, &temp))
		return -EINVAL;

	temp = clamp_val(temp, 0, 10000);
	temp = DIV_ROUND_CLOSEST(temp, 10);

	regs[0] = temp & 0xff;
	regs[1] = (temp >> 8) & 0xff;
	err = regmap_bulk_write(hwmon->regmap, reg, regs, 2);
	if (err)
		return err;

	return count;
}

static ssize_t pwm_auto_point_pwm_show(struct device *dev,
				       struct device_attribute *devattr,
				       char *buf)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);

	return sprintf(buf, "%d\n", 255 * (50 + (attr->index * 10)) / 100);
}

static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point1_pwm, pwm_auto_point_pwm, 0);
static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point1_temp, pwm_auto_point_temp, 0);

static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point2_pwm, pwm_auto_point_pwm, 1);
static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point2_temp, pwm_auto_point_temp, 1);

static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point3_pwm, pwm_auto_point_pwm, 2);
static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point3_temp, pwm_auto_point_temp, 2);

static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point4_pwm, pwm_auto_point_pwm, 3);
static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point4_temp, pwm_auto_point_temp, 3);

static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point5_pwm, pwm_auto_point_pwm, 4);
static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point5_temp, pwm_auto_point_temp, 4);

static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point6_pwm, pwm_auto_point_pwm, 5);
static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point6_temp, pwm_auto_point_temp, 5);

static struct attribute *gsc_hwmon_attributes[] = {
	&sensor_dev_attr_pwm1_auto_point1_pwm.dev_attr.attr,
	&sensor_dev_attr_pwm1_auto_point1_temp.dev_attr.attr,
	&sensor_dev_attr_pwm1_auto_point2_pwm.dev_attr.attr,
	&sensor_dev_attr_pwm1_auto_point2_temp.dev_attr.attr,
	&sensor_dev_attr_pwm1_auto_point3_pwm.dev_attr.attr,
	&sensor_dev_attr_pwm1_auto_point3_temp.dev_attr.attr,
	&sensor_dev_attr_pwm1_auto_point4_pwm.dev_attr.attr,
	&sensor_dev_attr_pwm1_auto_point4_temp.dev_attr.attr,
	&sensor_dev_attr_pwm1_auto_point5_pwm.dev_attr.attr,
	&sensor_dev_attr_pwm1_auto_point5_temp.dev_attr.attr,
	&sensor_dev_attr_pwm1_auto_point6_pwm.dev_attr.attr,
	&sensor_dev_attr_pwm1_auto_point6_temp.dev_attr.attr,
	NULL
};

static const struct attribute_group gsc_hwmon_group = {
	.attrs = gsc_hwmon_attributes,
};
__ATTRIBUTE_GROUPS(gsc_hwmon);

static int
gsc_hwmon_read(struct device *dev, enum hwmon_sensor_types type, u32 attr,
	       int channel, long *val)
{
	struct gsc_hwmon_data *hwmon = dev_get_drvdata(dev);
	const struct gsc_hwmon_channel *ch;
	int sz, ret;
	long tmp;
	u8 buf[3];

	switch (type) {
	case hwmon_in:
		ch = hwmon->in_ch[channel];
		break;
	case hwmon_temp:
		ch = hwmon->temp_ch[channel];
		break;
	case hwmon_fan:
		ch = hwmon->fan_ch[channel];
		break;
	default:
		return -EOPNOTSUPP;
	}

	sz = (ch->mode == mode_voltage_24bit) ? 3 : 2;
	ret = regmap_bulk_read(hwmon->regmap, ch->reg, buf, sz);
	if (ret)
		return ret;

	tmp = 0;
	while (sz-- > 0)
		tmp |= (buf[sz] << (8 * sz));

	switch (ch->mode) {
	case mode_temperature:
		if (tmp > 0x8000)
			tmp -= 0xffff;
		tmp *= 100; /* convert to millidegrees celsius */
		break;
	case mode_voltage_raw:
		tmp = clamp_val(tmp, 0, BIT(GSC_HWMON_RESOLUTION));
		/* scale based on ref voltage and ADC resolution */
		tmp *= GSC_HWMON_VREF;
		tmp >>= GSC_HWMON_RESOLUTION;
		/* scale based on optional voltage divider */
		if (ch->vdiv[0] && ch->vdiv[1]) {
			tmp *= (ch->vdiv[0] + ch->vdiv[1]);
			tmp /= ch->vdiv[1];
		}
		/* adjust by uV offset */
		tmp += ch->mvoffset;
		break;
	case mode_fan:
		tmp *= 30; /* convert to revolutions per minute */
		break;
	case mode_voltage_24bit:
	case mode_voltage_16bit:
		/* no adjustment needed */
		break;
	}

	*val = tmp;

	return 0;
}

static int
gsc_hwmon_read_string(struct device *dev, enum hwmon_sensor_types type,
		      u32 attr, int channel, const char **buf)
{
	struct gsc_hwmon_data *hwmon = dev_get_drvdata(dev);

	switch (type) {
	case hwmon_in:
		*buf = hwmon->in_ch[channel]->name;
		break;
	case hwmon_temp:
		*buf = hwmon->temp_ch[channel]->name;
		break;
	case hwmon_fan:
		*buf = hwmon->fan_ch[channel]->name;
		break;
	default:
		return -ENOTSUPP;
	}

	return 0;
}

static umode_t
gsc_hwmon_is_visible(const void *_data, enum hwmon_sensor_types type, u32 attr,
		     int ch)
{
	return 0444;
}

static const struct hwmon_ops gsc_hwmon_ops = {
	.is_visible = gsc_hwmon_is_visible,
	.read = gsc_hwmon_read,
	.read_string = gsc_hwmon_read_string,
};

static struct gsc_hwmon_platform_data *
gsc_hwmon_get_devtree_pdata(struct device *dev)
{
	struct gsc_hwmon_platform_data *pdata;
	struct gsc_hwmon_channel *ch;
	struct fwnode_handle *child;
	struct device_node *fan;
	int nchannels;

	nchannels = device_get_child_node_count(dev);
	if (nchannels == 0)
		return ERR_PTR(-ENODEV);

	pdata = devm_kzalloc(dev,
			     sizeof(*pdata) + nchannels * sizeof(*ch),
			     GFP_KERNEL);
	if (!pdata)
		return ERR_PTR(-ENOMEM);
	ch = (struct gsc_hwmon_channel *)(pdata + 1);
	pdata->channels = ch;
	pdata->nchannels = nchannels;

	/* fan controller base address */
	fan = of_find_compatible_node(dev->parent->of_node, NULL, "gw,gsc-fan");
	if (fan && of_property_read_u32(fan, "reg", &pdata->fan_base)) {
		of_node_put(fan);
		dev_err(dev, "fan node without base\n");
		return ERR_PTR(-EINVAL);
	}

	of_node_put(fan);

	/* allocate structures for channels and count instances of each type */
	device_for_each_child_node(dev, child) {
		if (fwnode_property_read_string(child, "label", &ch->name)) {
			dev_err(dev, "channel without label\n");
			fwnode_handle_put(child);
			return ERR_PTR(-EINVAL);
		}
		if (fwnode_property_read_u32(child, "reg", &ch->reg)) {
			dev_err(dev, "channel without reg\n");
			fwnode_handle_put(child);
			return ERR_PTR(-EINVAL);
		}
		if (fwnode_property_read_u32(child, "gw,mode", &ch->mode)) {
			dev_err(dev, "channel without mode\n");
			fwnode_handle_put(child);
			return ERR_PTR(-EINVAL);
		}
		if (ch->mode > mode_max) {
			dev_err(dev, "invalid channel mode\n");
			fwnode_handle_put(child);
			return ERR_PTR(-EINVAL);
		}

		if (!fwnode_property_read_u32(child,
					      "gw,voltage-offset-microvolt",
					      &ch->mvoffset))
			ch->mvoffset /= 1000;
		fwnode_property_read_u32_array(child,
					       "gw,voltage-divider-ohms",
					       ch->vdiv, ARRAY_SIZE(ch->vdiv));
		ch++;
	}

	return pdata;
}

static int gsc_hwmon_probe(struct platform_device *pdev)
{
	struct gsc_dev *gsc = dev_get_drvdata(pdev->dev.parent);
	struct device *dev = &pdev->dev;
	struct device *hwmon_dev;
	struct gsc_hwmon_platform_data *pdata = dev_get_platdata(dev);
	struct gsc_hwmon_data *hwmon;
	const struct attribute_group **groups;
	int i, i_in, i_temp, i_fan;

	if (!pdata) {
		pdata = gsc_hwmon_get_devtree_pdata(dev);
		if (IS_ERR(pdata))
			return PTR_ERR(pdata);
	}

	hwmon = devm_kzalloc(dev, sizeof(*hwmon), GFP_KERNEL);
	if (!hwmon)
		return -ENOMEM;
	hwmon->gsc = gsc;
	hwmon->pdata = pdata;

	hwmon->regmap = devm_regmap_init(dev, &gsc_hwmon_regmap_bus,
					 gsc->i2c_hwmon,
					 &gsc_hwmon_regmap_config);
	if (IS_ERR(hwmon->regmap))
		return PTR_ERR(hwmon->regmap);

	for (i = 0, i_in = 0, i_temp = 0, i_fan = 0; i < hwmon->pdata->nchannels; i++) {
		const struct gsc_hwmon_channel *ch = &pdata->channels[i];

		switch (ch->mode) {
		case mode_temperature:
			if (i_temp == GSC_HWMON_MAX_TEMP_CH) {
				dev_err(gsc->dev, "too many temp channels\n");
				return -EINVAL;
			}
			hwmon->temp_ch[i_temp] = ch;
			hwmon->temp_config[i_temp] = HWMON_T_INPUT |
						     HWMON_T_LABEL;
			i_temp++;
			break;
		case mode_fan:
			if (i_fan == GSC_HWMON_MAX_FAN_CH) {
				dev_err(gsc->dev, "too many fan channels\n");
				return -EINVAL;
			}
			hwmon->fan_ch[i_fan] = ch;
			hwmon->fan_config[i_fan] = HWMON_F_INPUT |
						   HWMON_F_LABEL;
			i_fan++;
			break;
		case mode_voltage_24bit:
		case mode_voltage_16bit:
		case mode_voltage_raw:
			if (i_in == GSC_HWMON_MAX_IN_CH) {
				dev_err(gsc->dev, "too many input channels\n");
				return -EINVAL;
			}
			hwmon->in_ch[i_in] = ch;
			hwmon->in_config[i_in] =
				HWMON_I_INPUT | HWMON_I_LABEL;
			i_in++;
			break;
		default:
			dev_err(gsc->dev, "invalid mode: %d\n", ch->mode);
			return -EINVAL;
		}
	}

	/* setup config structures */
	hwmon->chip.ops = &gsc_hwmon_ops;
	hwmon->chip.info = hwmon->info;
	hwmon->info[0] = &hwmon->temp_info;
	hwmon->info[1] = &hwmon->in_info;
	hwmon->info[2] = &hwmon->fan_info;
	hwmon->temp_info.type = hwmon_temp;
	hwmon->temp_info.config = hwmon->temp_config;
	hwmon->in_info.type = hwmon_in;
	hwmon->in_info.config = hwmon->in_config;
	hwmon->fan_info.type = hwmon_fan;
	hwmon->fan_info.config = hwmon->fan_config;

	groups = pdata->fan_base ? gsc_hwmon_groups : NULL;
	hwmon_dev = devm_hwmon_device_register_with_info(dev,
							 KBUILD_MODNAME, hwmon,
							 &hwmon->chip, groups);
	return PTR_ERR_OR_ZERO(hwmon_dev);
}

static const struct of_device_id gsc_hwmon_of_match[] = {
	{ .compatible = "gw,gsc-adc", },
	{}
};

static struct platform_driver gsc_hwmon_driver = {
	.driver = {
		.name = "gsc-hwmon",
		.of_match_table = gsc_hwmon_of_match,
	},
	.probe = gsc_hwmon_probe,
};

module_platform_driver(gsc_hwmon_driver);

MODULE_AUTHOR("Tim Harvey <tharvey@gateworks.com>");
MODULE_DESCRIPTION("GSC hardware monitor driver");
MODULE_LICENSE("GPL v2");