1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Thermal device driver for DA9062 and DA9061 |
4 | * Copyright (C) 2017 Dialog Semiconductor |
5 | */ |
6 | |
7 | /* When over-temperature is reached, an interrupt from the device will be |
8 | * triggered. Following this event the interrupt will be disabled and |
9 | * periodic transmission of uevents (HOT trip point) should define the |
10 | * first level of temperature supervision. It is expected that any final |
11 | * implementation of the thermal driver will include a .notify() function |
12 | * to implement these uevents to userspace. |
13 | * |
14 | * These uevents are intended to indicate non-invasive temperature control |
15 | * of the system, where the necessary measures for cooling are the |
16 | * responsibility of the host software. Once the temperature falls again, |
17 | * the IRQ is re-enabled so the start of a new over-temperature event can |
18 | * be detected without constant software monitoring. |
19 | */ |
20 | |
21 | #include <linux/errno.h> |
22 | #include <linux/interrupt.h> |
23 | #include <linux/module.h> |
24 | #include <linux/of.h> |
25 | #include <linux/platform_device.h> |
26 | #include <linux/regmap.h> |
27 | #include <linux/thermal.h> |
28 | #include <linux/workqueue.h> |
29 | |
30 | #include <linux/mfd/da9062/core.h> |
31 | #include <linux/mfd/da9062/registers.h> |
32 | |
33 | /* Minimum, maximum and default polling millisecond periods are provided |
34 | * here as an example. It is expected that any final implementation to also |
35 | * include a modification of these settings to match the required |
36 | * application. |
37 | */ |
38 | #define DA9062_DEFAULT_POLLING_MS_PERIOD 3000 |
39 | #define DA9062_MAX_POLLING_MS_PERIOD 10000 |
40 | #define DA9062_MIN_POLLING_MS_PERIOD 1000 |
41 | |
42 | #define DA9062_MILLI_CELSIUS(t) ((t) * 1000) |
43 | |
44 | static unsigned int pp_tmp = DA9062_DEFAULT_POLLING_MS_PERIOD; |
45 | |
46 | struct da9062_thermal_config { |
47 | const char *name; |
48 | }; |
49 | |
50 | struct da9062_thermal { |
51 | struct da9062 *hw; |
52 | struct delayed_work work; |
53 | struct thermal_zone_device *zone; |
54 | struct mutex lock; /* protection for da9062_thermal temperature */ |
55 | int temperature; |
56 | int irq; |
57 | const struct da9062_thermal_config *config; |
58 | struct device *dev; |
59 | }; |
60 | |
61 | static void da9062_thermal_poll_on(struct work_struct *work) |
62 | { |
63 | struct da9062_thermal *thermal = container_of(work, |
64 | struct da9062_thermal, |
65 | work.work); |
66 | unsigned long delay; |
67 | unsigned int val; |
68 | int ret; |
69 | |
70 | /* clear E_TEMP */ |
71 | ret = regmap_write(map: thermal->hw->regmap, |
72 | DA9062AA_EVENT_B, |
73 | DA9062AA_E_TEMP_MASK); |
74 | if (ret < 0) { |
75 | dev_err(thermal->dev, |
76 | "Cannot clear the TJUNC temperature status\n" ); |
77 | goto err_enable_irq; |
78 | } |
79 | |
80 | /* Now read E_TEMP again: it is acting like a status bit. |
81 | * If over-temperature, then this status will be true. |
82 | * If not over-temperature, this status will be false. |
83 | */ |
84 | ret = regmap_read(map: thermal->hw->regmap, |
85 | DA9062AA_EVENT_B, |
86 | val: &val); |
87 | if (ret < 0) { |
88 | dev_err(thermal->dev, |
89 | "Cannot check the TJUNC temperature status\n" ); |
90 | goto err_enable_irq; |
91 | } |
92 | |
93 | if (val & DA9062AA_E_TEMP_MASK) { |
94 | mutex_lock(&thermal->lock); |
95 | thermal->temperature = DA9062_MILLI_CELSIUS(125); |
96 | mutex_unlock(lock: &thermal->lock); |
97 | thermal_zone_device_update(thermal->zone, |
98 | THERMAL_EVENT_UNSPECIFIED); |
99 | |
100 | /* |
101 | * pp_tmp is between 1s and 10s, so we can round the jiffies |
102 | */ |
103 | delay = round_jiffies(j: msecs_to_jiffies(m: pp_tmp)); |
104 | queue_delayed_work(wq: system_freezable_wq, dwork: &thermal->work, delay); |
105 | return; |
106 | } |
107 | |
108 | mutex_lock(&thermal->lock); |
109 | thermal->temperature = DA9062_MILLI_CELSIUS(0); |
110 | mutex_unlock(lock: &thermal->lock); |
111 | thermal_zone_device_update(thermal->zone, |
112 | THERMAL_EVENT_UNSPECIFIED); |
113 | |
114 | err_enable_irq: |
115 | enable_irq(irq: thermal->irq); |
116 | } |
117 | |
118 | static irqreturn_t da9062_thermal_irq_handler(int irq, void *data) |
119 | { |
120 | struct da9062_thermal *thermal = data; |
121 | |
122 | disable_irq_nosync(irq: thermal->irq); |
123 | queue_delayed_work(wq: system_freezable_wq, dwork: &thermal->work, delay: 0); |
124 | |
125 | return IRQ_HANDLED; |
126 | } |
127 | |
128 | static int da9062_thermal_get_temp(struct thermal_zone_device *z, |
129 | int *temp) |
130 | { |
131 | struct da9062_thermal *thermal = thermal_zone_device_priv(tzd: z); |
132 | |
133 | mutex_lock(&thermal->lock); |
134 | *temp = thermal->temperature; |
135 | mutex_unlock(lock: &thermal->lock); |
136 | |
137 | return 0; |
138 | } |
139 | |
140 | static struct thermal_zone_device_ops da9062_thermal_ops = { |
141 | .get_temp = da9062_thermal_get_temp, |
142 | }; |
143 | |
144 | static struct thermal_trip trips[] = { |
145 | { .temperature = DA9062_MILLI_CELSIUS(125), .type = THERMAL_TRIP_HOT }, |
146 | }; |
147 | |
148 | static const struct da9062_thermal_config da9062_config = { |
149 | .name = "da9062-thermal" , |
150 | }; |
151 | |
152 | static const struct of_device_id da9062_compatible_reg_id_table[] = { |
153 | { .compatible = "dlg,da9062-thermal" , .data = &da9062_config }, |
154 | { }, |
155 | }; |
156 | |
157 | MODULE_DEVICE_TABLE(of, da9062_compatible_reg_id_table); |
158 | |
159 | static int da9062_thermal_probe(struct platform_device *pdev) |
160 | { |
161 | struct da9062 *chip = dev_get_drvdata(dev: pdev->dev.parent); |
162 | struct da9062_thermal *thermal; |
163 | const struct of_device_id *match; |
164 | int ret = 0; |
165 | |
166 | match = of_match_node(matches: da9062_compatible_reg_id_table, |
167 | node: pdev->dev.of_node); |
168 | if (!match) |
169 | return -ENXIO; |
170 | |
171 | if (pdev->dev.of_node) { |
172 | if (!of_property_read_u32(np: pdev->dev.of_node, |
173 | propname: "polling-delay-passive" , |
174 | out_value: &pp_tmp)) { |
175 | if (pp_tmp < DA9062_MIN_POLLING_MS_PERIOD || |
176 | pp_tmp > DA9062_MAX_POLLING_MS_PERIOD) { |
177 | dev_warn(&pdev->dev, |
178 | "Out-of-range polling period %d ms\n" , |
179 | pp_tmp); |
180 | pp_tmp = DA9062_DEFAULT_POLLING_MS_PERIOD; |
181 | } |
182 | } |
183 | } |
184 | |
185 | thermal = devm_kzalloc(dev: &pdev->dev, size: sizeof(struct da9062_thermal), |
186 | GFP_KERNEL); |
187 | if (!thermal) { |
188 | ret = -ENOMEM; |
189 | goto err; |
190 | } |
191 | |
192 | thermal->config = match->data; |
193 | thermal->hw = chip; |
194 | thermal->dev = &pdev->dev; |
195 | |
196 | INIT_DELAYED_WORK(&thermal->work, da9062_thermal_poll_on); |
197 | mutex_init(&thermal->lock); |
198 | |
199 | thermal->zone = thermal_zone_device_register_with_trips(type: thermal->config->name, |
200 | trips, ARRAY_SIZE(trips), mask: 0, devdata: thermal, |
201 | ops: &da9062_thermal_ops, NULL, passive_delay: pp_tmp, |
202 | polling_delay: 0); |
203 | if (IS_ERR(ptr: thermal->zone)) { |
204 | dev_err(&pdev->dev, "Cannot register thermal zone device\n" ); |
205 | ret = PTR_ERR(ptr: thermal->zone); |
206 | goto err; |
207 | } |
208 | ret = thermal_zone_device_enable(tz: thermal->zone); |
209 | if (ret) { |
210 | dev_err(&pdev->dev, "Cannot enable thermal zone device\n" ); |
211 | goto err_zone; |
212 | } |
213 | |
214 | dev_dbg(&pdev->dev, |
215 | "TJUNC temperature polling period set at %d ms\n" , pp_tmp); |
216 | |
217 | ret = platform_get_irq_byname(pdev, "THERMAL" ); |
218 | if (ret < 0) |
219 | goto err_zone; |
220 | |
221 | thermal->irq = ret; |
222 | |
223 | ret = request_threaded_irq(irq: thermal->irq, NULL, |
224 | thread_fn: da9062_thermal_irq_handler, |
225 | IRQF_TRIGGER_LOW | IRQF_ONESHOT, |
226 | name: "THERMAL" , dev: thermal); |
227 | if (ret) { |
228 | dev_err(&pdev->dev, |
229 | "Failed to request thermal device IRQ.\n" ); |
230 | goto err_zone; |
231 | } |
232 | |
233 | platform_set_drvdata(pdev, data: thermal); |
234 | return 0; |
235 | |
236 | err_zone: |
237 | thermal_zone_device_unregister(tz: thermal->zone); |
238 | err: |
239 | return ret; |
240 | } |
241 | |
242 | static void da9062_thermal_remove(struct platform_device *pdev) |
243 | { |
244 | struct da9062_thermal *thermal = platform_get_drvdata(pdev); |
245 | |
246 | free_irq(thermal->irq, thermal); |
247 | cancel_delayed_work_sync(dwork: &thermal->work); |
248 | thermal_zone_device_unregister(tz: thermal->zone); |
249 | } |
250 | |
251 | static struct platform_driver da9062_thermal_driver = { |
252 | .probe = da9062_thermal_probe, |
253 | .remove_new = da9062_thermal_remove, |
254 | .driver = { |
255 | .name = "da9062-thermal" , |
256 | .of_match_table = da9062_compatible_reg_id_table, |
257 | }, |
258 | }; |
259 | |
260 | module_platform_driver(da9062_thermal_driver); |
261 | |
262 | MODULE_AUTHOR("Steve Twiss" ); |
263 | MODULE_DESCRIPTION("Thermal TJUNC device driver for Dialog DA9062 and DA9061" ); |
264 | MODULE_LICENSE("GPL" ); |
265 | MODULE_ALIAS("platform:da9062-thermal" ); |
266 | |