summaryrefslogtreecommitdiffstats
path: root/drivers/thermal/ti-soc-thermal/ti-thermal-common.c
blob: 2ce4b19f312ac66724788dc9f1f628ffb3ea6f01 (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
// SPDX-License-Identifier: GPL-2.0-only
/*
 * OMAP thermal driver interface
 *
 * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
 * Contact:
 *   Eduardo Valentin <eduardo.valentin@ti.com>
 */

#include <linux/device.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/gfp.h>
#include <linux/kernel.h>
#include <linux/workqueue.h>
#include <linux/thermal.h>
#include <linux/cpufreq.h>
#include <linux/cpumask.h>
#include <linux/cpu_cooling.h>
#include <linux/of.h>

#include "ti-thermal.h"
#include "ti-bandgap.h"

/* common data structures */
struct ti_thermal_data {
	struct cpufreq_policy *policy;
	struct thermal_zone_device *ti_thermal;
	struct thermal_zone_device *pcb_tz;
	struct thermal_cooling_device *cool_dev;
	struct ti_bandgap *bgp;
	enum thermal_device_mode mode;
	struct work_struct thermal_wq;
	int sensor_id;
	bool our_zone;
};

static void ti_thermal_work(struct work_struct *work)
{
	struct ti_thermal_data *data = container_of(work,
					struct ti_thermal_data, thermal_wq);

	thermal_zone_device_update(data->ti_thermal, THERMAL_EVENT_UNSPECIFIED);

	dev_dbg(&data->ti_thermal->device, "updated thermal zone %s\n",
		data->ti_thermal->type);
}

/**
 * ti_thermal_hotspot_temperature - returns sensor extrapolated temperature
 * @t:	omap sensor temperature
 * @s:	omap sensor slope value
 * @c:	omap sensor const value
 */
static inline int ti_thermal_hotspot_temperature(int t, int s, int c)
{
	int delta = t * s / 1000 + c;

	if (delta < 0)
		delta = 0;

	return t + delta;
}

/* thermal zone ops */
/* Get temperature callback function for thermal zone */
static inline int __ti_thermal_get_temp(void *devdata, int *temp)
{
	struct thermal_zone_device *pcb_tz = NULL;
	struct ti_thermal_data *data = devdata;
	struct ti_bandgap *bgp;
	const struct ti_temp_sensor *s;
	int ret, tmp, slope, constant;
	int pcb_temp;

	if (!data)
		return 0;

	bgp = data->bgp;
	s = &bgp->conf->sensors[data->sensor_id];

	ret = ti_bandgap_read_temperature(bgp, data->sensor_id, &tmp);
	if (ret)
		return ret;

	/* Default constants */
	slope = thermal_zone_get_slope(data->ti_thermal);
	constant = thermal_zone_get_offset(data->ti_thermal);

	pcb_tz = data->pcb_tz;
	/* In case pcb zone is available, use the extrapolation rule with it */
	if (!IS_ERR(pcb_tz)) {
		ret = thermal_zone_get_temp(pcb_tz, &pcb_temp);
		if (!ret) {
			tmp -= pcb_temp; /* got a valid PCB temp */
			slope = s->slope_pcb;
			constant = s->constant_pcb;
		} else {
			dev_err(bgp->dev,
				"Failed to read PCB state. Using defaults\n");
			ret = 0;
		}
	}
	*temp = ti_thermal_hotspot_temperature(tmp, slope, constant);

	return ret;
}

static inline int ti_thermal_get_temp(struct thermal_zone_device *thermal,
				      int *temp)
{
	struct ti_thermal_data *data = thermal->devdata;

	return __ti_thermal_get_temp(data, temp);
}

static int __ti_thermal_get_trend(void *p, int trip, enum thermal_trend *trend)
{
	struct ti_thermal_data *data = p;
	struct ti_bandgap *bgp;
	int id, tr, ret = 0;

	bgp = data->bgp;
	id = data->sensor_id;

	ret = ti_bandgap_get_trend(bgp, id, &tr);
	if (ret)
		return ret;

	if (tr > 0)
		*trend = THERMAL_TREND_RAISING;
	else if (tr < 0)
		*trend = THERMAL_TREND_DROPPING;
	else
		*trend = THERMAL_TREND_STABLE;

	return 0;
}

static const struct thermal_zone_of_device_ops ti_of_thermal_ops = {
	.get_temp = __ti_thermal_get_temp,
	.get_trend = __ti_thermal_get_trend,
};

static struct ti_thermal_data
*ti_thermal_build_data(struct ti_bandgap *bgp, int id)
{
	struct ti_thermal_data *data;

	data = devm_kzalloc(bgp->dev, sizeof(*data), GFP_KERNEL);
	if (!data) {
		dev_err(bgp->dev, "kzalloc fail\n");
		return NULL;
	}
	data->sensor_id = id;
	data->bgp = bgp;
	data->mode = THERMAL_DEVICE_ENABLED;
	/* pcb_tz will be either valid or PTR_ERR() */
	data->pcb_tz = thermal_zone_get_zone_by_name("pcb");
	INIT_WORK(&data->thermal_wq, ti_thermal_work);

	return data;
}

int ti_thermal_expose_sensor(struct ti_bandgap *bgp, int id,
			     char *domain)
{
	struct ti_thermal_data *data;

	data = ti_bandgap_get_sensor_data(bgp, id);

	if (IS_ERR_OR_NULL(data))
		data = ti_thermal_build_data(bgp, id);

	if (!data)
		return -EINVAL;

	/* in case this is specified by DT */
	data->ti_thermal = devm_thermal_zone_of_sensor_register(bgp->dev, id,
					data, &ti_of_thermal_ops);
	if (IS_ERR(data->ti_thermal)) {
		dev_err(bgp->dev, "thermal zone device is NULL\n");
		return PTR_ERR(data->ti_thermal);
	}

	ti_bandgap_set_sensor_data(bgp, id, data);
	ti_bandgap_write_update_interval(bgp, data->sensor_id,
					data->ti_thermal->polling_delay);

	return 0;
}

int ti_thermal_remove_sensor(struct ti_bandgap *bgp, int id)
{
	struct ti_thermal_data *data;

	data = ti_bandgap_get_sensor_data(bgp, id);

	if (!IS_ERR_OR_NULL(data) && data->ti_thermal) {
		if (data->our_zone)
			thermal_zone_device_unregister(data->ti_thermal);
	}

	return 0;
}

int ti_thermal_report_sensor_temperature(struct ti_bandgap *bgp, int id)
{
	struct ti_thermal_data *data;

	data = ti_bandgap_get_sensor_data(bgp, id);

	schedule_work(&data->thermal_wq);

	return 0;
}

int ti_thermal_register_cpu_cooling(struct ti_bandgap *bgp, int id)
{
	struct ti_thermal_data *data;
	struct device_node *np = bgp->dev->of_node;

	/*
	 * We are assuming here that if one deploys the zone
	 * using DT, then it must be aware that the cooling device
	 * loading has to happen via cpufreq driver.
	 */
	if (of_find_property(np, "#thermal-sensor-cells", NULL))
		return 0;

	data = ti_bandgap_get_sensor_data(bgp, id);
	if (!data || IS_ERR(data))
		data = ti_thermal_build_data(bgp, id);

	if (!data)
		return -EINVAL;

	data->policy = cpufreq_cpu_get(0);
	if (!data->policy) {
		pr_debug("%s: CPUFreq policy not found\n", __func__);
		return -EPROBE_DEFER;
	}

	/* Register cooling device */
	data->cool_dev = cpufreq_cooling_register(data->policy);
	if (IS_ERR(data->cool_dev)) {
		int ret = PTR_ERR(data->cool_dev);
		dev_err(bgp->dev, "Failed to register cpu cooling device %d\n",
			ret);
		cpufreq_cpu_put(data->policy);

		return ret;
	}
	ti_bandgap_set_sensor_data(bgp, id, data);

	return 0;
}

int ti_thermal_unregister_cpu_cooling(struct ti_bandgap *bgp, int id)
{
	struct ti_thermal_data *data;

	data = ti_bandgap_get_sensor_data(bgp, id);

	if (!IS_ERR_OR_NULL(data)) {
		cpufreq_cooling_unregister(data->cool_dev);
		if (data->policy)
			cpufreq_cpu_put(data->policy);
	}

	return 0;
}