1 // SPDX-License-Identifier: GPL-2.0-only
3 * OMAP thermal driver interface
5 * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
7 * Eduardo Valentin <eduardo.valentin@ti.com>
10 #include <linux/device.h>
11 #include <linux/err.h>
12 #include <linux/mutex.h>
13 #include <linux/gfp.h>
14 #include <linux/kernel.h>
15 #include <linux/workqueue.h>
16 #include <linux/thermal.h>
17 #include <linux/cpufreq.h>
18 #include <linux/cpumask.h>
19 #include <linux/cpu_cooling.h>
22 #include "ti-thermal.h"
23 #include "ti-bandgap.h"
25 /* common data structures */
26 struct ti_thermal_data {
27 struct cpufreq_policy *policy;
28 struct thermal_zone_device *ti_thermal;
29 struct thermal_zone_device *pcb_tz;
30 struct thermal_cooling_device *cool_dev;
31 struct ti_bandgap *bgp;
32 enum thermal_device_mode mode;
33 struct work_struct thermal_wq;
38 static void ti_thermal_work(struct work_struct *work)
40 struct ti_thermal_data *data = container_of(work,
41 struct ti_thermal_data, thermal_wq);
43 thermal_zone_device_update(data->ti_thermal, THERMAL_EVENT_UNSPECIFIED);
45 dev_dbg(&data->ti_thermal->device, "updated thermal zone %s\n",
46 data->ti_thermal->type);
50 * ti_thermal_hotspot_temperature - returns sensor extrapolated temperature
51 * @t: omap sensor temperature
52 * @s: omap sensor slope value
53 * @c: omap sensor const value
55 static inline int ti_thermal_hotspot_temperature(int t, int s, int c)
57 int delta = t * s / 1000 + c;
65 /* thermal zone ops */
66 /* Get temperature callback function for thermal zone */
67 static inline int __ti_thermal_get_temp(void *devdata, int *temp)
69 struct thermal_zone_device *pcb_tz = NULL;
70 struct ti_thermal_data *data = devdata;
71 struct ti_bandgap *bgp;
72 const struct ti_temp_sensor *s;
73 int ret, tmp, slope, constant;
80 s = &bgp->conf->sensors[data->sensor_id];
82 ret = ti_bandgap_read_temperature(bgp, data->sensor_id, &tmp);
86 /* Default constants */
87 slope = thermal_zone_get_slope(data->ti_thermal);
88 constant = thermal_zone_get_offset(data->ti_thermal);
90 pcb_tz = data->pcb_tz;
91 /* In case pcb zone is available, use the extrapolation rule with it */
92 if (!IS_ERR(pcb_tz)) {
93 ret = thermal_zone_get_temp(pcb_tz, &pcb_temp);
95 tmp -= pcb_temp; /* got a valid PCB temp */
97 constant = s->constant_pcb;
100 "Failed to read PCB state. Using defaults\n");
104 *temp = ti_thermal_hotspot_temperature(tmp, slope, constant);
109 static inline int ti_thermal_get_temp(struct thermal_zone_device *thermal,
112 struct ti_thermal_data *data = thermal->devdata;
114 return __ti_thermal_get_temp(data, temp);
117 static int __ti_thermal_get_trend(void *p, int trip, enum thermal_trend *trend)
119 struct ti_thermal_data *data = p;
120 struct ti_bandgap *bgp;
124 id = data->sensor_id;
126 ret = ti_bandgap_get_trend(bgp, id, &tr);
131 *trend = THERMAL_TREND_RAISING;
133 *trend = THERMAL_TREND_DROPPING;
135 *trend = THERMAL_TREND_STABLE;
140 static const struct thermal_zone_of_device_ops ti_of_thermal_ops = {
141 .get_temp = __ti_thermal_get_temp,
142 .get_trend = __ti_thermal_get_trend,
145 static struct ti_thermal_data
146 *ti_thermal_build_data(struct ti_bandgap *bgp, int id)
148 struct ti_thermal_data *data;
150 data = devm_kzalloc(bgp->dev, sizeof(*data), GFP_KERNEL);
152 dev_err(bgp->dev, "kzalloc fail\n");
155 data->sensor_id = id;
157 data->mode = THERMAL_DEVICE_ENABLED;
158 /* pcb_tz will be either valid or PTR_ERR() */
159 data->pcb_tz = thermal_zone_get_zone_by_name("pcb");
160 INIT_WORK(&data->thermal_wq, ti_thermal_work);
165 int ti_thermal_expose_sensor(struct ti_bandgap *bgp, int id,
168 struct ti_thermal_data *data;
171 data = ti_bandgap_get_sensor_data(bgp, id);
173 if (IS_ERR_OR_NULL(data))
174 data = ti_thermal_build_data(bgp, id);
179 /* in case this is specified by DT */
180 data->ti_thermal = devm_thermal_zone_of_sensor_register(bgp->dev, id,
181 data, &ti_of_thermal_ops);
182 if (IS_ERR(data->ti_thermal)) {
183 dev_err(bgp->dev, "thermal zone device is NULL\n");
184 return PTR_ERR(data->ti_thermal);
187 interval = jiffies_to_msecs(data->ti_thermal->polling_delay_jiffies);
189 ti_bandgap_set_sensor_data(bgp, id, data);
190 ti_bandgap_write_update_interval(bgp, data->sensor_id, interval);
195 int ti_thermal_remove_sensor(struct ti_bandgap *bgp, int id)
197 struct ti_thermal_data *data;
199 data = ti_bandgap_get_sensor_data(bgp, id);
201 if (!IS_ERR_OR_NULL(data) && data->ti_thermal) {
203 thermal_zone_device_unregister(data->ti_thermal);
209 int ti_thermal_report_sensor_temperature(struct ti_bandgap *bgp, int id)
211 struct ti_thermal_data *data;
213 data = ti_bandgap_get_sensor_data(bgp, id);
215 schedule_work(&data->thermal_wq);
220 int ti_thermal_register_cpu_cooling(struct ti_bandgap *bgp, int id)
222 struct ti_thermal_data *data;
223 struct device_node *np = bgp->dev->of_node;
226 * We are assuming here that if one deploys the zone
227 * using DT, then it must be aware that the cooling device
228 * loading has to happen via cpufreq driver.
230 if (of_find_property(np, "#thermal-sensor-cells", NULL))
233 data = ti_bandgap_get_sensor_data(bgp, id);
234 if (!data || IS_ERR(data))
235 data = ti_thermal_build_data(bgp, id);
240 data->policy = cpufreq_cpu_get(0);
242 pr_debug("%s: CPUFreq policy not found\n", __func__);
243 return -EPROBE_DEFER;
246 /* Register cooling device */
247 data->cool_dev = cpufreq_cooling_register(data->policy);
248 if (IS_ERR(data->cool_dev)) {
249 int ret = PTR_ERR(data->cool_dev);
250 dev_err(bgp->dev, "Failed to register cpu cooling device %d\n",
252 cpufreq_cpu_put(data->policy);
256 ti_bandgap_set_sensor_data(bgp, id, data);
261 int ti_thermal_unregister_cpu_cooling(struct ti_bandgap *bgp, int id)
263 struct ti_thermal_data *data;
265 data = ti_bandgap_get_sensor_data(bgp, id);
267 if (!IS_ERR_OR_NULL(data)) {
268 cpufreq_cooling_unregister(data->cool_dev);
270 cpufreq_cpu_put(data->policy);