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1e426ffd KM |
1 | /* |
2 | * R-Car THS/TSC thermal sensor driver | |
3 | * | |
4 | * Copyright (C) 2012 Renesas Solutions Corp. | |
5 | * Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License as published by | |
9 | * the Free Software Foundation; version 2 of the License. | |
10 | * | |
11 | * This program is distributed in the hope that it will be useful, but | |
12 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
14 | * General Public License for more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License along | |
17 | * with this program; if not, write to the Free Software Foundation, Inc., | |
18 | * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. | |
19 | */ | |
20 | #include <linux/delay.h> | |
21 | #include <linux/err.h> | |
22 | #include <linux/io.h> | |
23 | #include <linux/module.h> | |
24 | #include <linux/platform_device.h> | |
25 | #include <linux/slab.h> | |
26 | #include <linux/spinlock.h> | |
27 | #include <linux/thermal.h> | |
28 | ||
29 | #define THSCR 0x2c | |
30 | #define THSSR 0x30 | |
31 | ||
32 | /* THSCR */ | |
33 | #define CPTAP 0xf | |
34 | ||
35 | /* THSSR */ | |
36 | #define CTEMP 0x3f | |
37 | ||
38 | ||
39 | struct rcar_thermal_priv { | |
40 | void __iomem *base; | |
41 | struct device *dev; | |
42 | spinlock_t lock; | |
43 | u32 comp; | |
44 | }; | |
45 | ||
c499703e | 46 | #define MCELSIUS(temp) ((temp) * 1000) |
d12250ef | 47 | #define rcar_zone_to_priv(zone) (zone->devdata) |
c499703e | 48 | |
1e426ffd KM |
49 | /* |
50 | * basic functions | |
51 | */ | |
52 | static u32 rcar_thermal_read(struct rcar_thermal_priv *priv, u32 reg) | |
53 | { | |
54 | unsigned long flags; | |
55 | u32 ret; | |
56 | ||
57 | spin_lock_irqsave(&priv->lock, flags); | |
58 | ||
59 | ret = ioread32(priv->base + reg); | |
60 | ||
61 | spin_unlock_irqrestore(&priv->lock, flags); | |
62 | ||
63 | return ret; | |
64 | } | |
65 | ||
66 | #if 0 /* no user at this point */ | |
67 | static void rcar_thermal_write(struct rcar_thermal_priv *priv, | |
68 | u32 reg, u32 data) | |
69 | { | |
70 | unsigned long flags; | |
71 | ||
72 | spin_lock_irqsave(&priv->lock, flags); | |
73 | ||
74 | iowrite32(data, priv->base + reg); | |
75 | ||
76 | spin_unlock_irqrestore(&priv->lock, flags); | |
77 | } | |
78 | #endif | |
79 | ||
80 | static void rcar_thermal_bset(struct rcar_thermal_priv *priv, u32 reg, | |
81 | u32 mask, u32 data) | |
82 | { | |
83 | unsigned long flags; | |
84 | u32 val; | |
85 | ||
86 | spin_lock_irqsave(&priv->lock, flags); | |
87 | ||
88 | val = ioread32(priv->base + reg); | |
89 | val &= ~mask; | |
90 | val |= (data & mask); | |
91 | iowrite32(val, priv->base + reg); | |
92 | ||
93 | spin_unlock_irqrestore(&priv->lock, flags); | |
94 | } | |
95 | ||
96 | /* | |
97 | * zone device functions | |
98 | */ | |
99 | static int rcar_thermal_get_temp(struct thermal_zone_device *zone, | |
100 | unsigned long *temp) | |
101 | { | |
d12250ef | 102 | struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone); |
1e426ffd KM |
103 | int val, min, max, tmp; |
104 | ||
105 | tmp = -200; /* default */ | |
106 | while (1) { | |
107 | if (priv->comp < 1 || priv->comp > 12) { | |
108 | dev_err(priv->dev, | |
109 | "THSSR invalid data (%d)\n", priv->comp); | |
110 | priv->comp = 4; /* for next thermal */ | |
111 | return -EINVAL; | |
112 | } | |
113 | ||
114 | /* | |
115 | * THS comparator offset and the reference temperature | |
116 | * | |
117 | * Comparator | reference | Temperature field | |
118 | * offset | temperature | measurement | |
119 | * | (degrees C) | (degrees C) | |
120 | * -------------+---------------+------------------- | |
121 | * 1 | -45 | -45 to -30 | |
122 | * 2 | -30 | -30 to -15 | |
123 | * 3 | -15 | -15 to 0 | |
124 | * 4 | 0 | 0 to +15 | |
125 | * 5 | +15 | +15 to +30 | |
126 | * 6 | +30 | +30 to +45 | |
127 | * 7 | +45 | +45 to +60 | |
128 | * 8 | +60 | +60 to +75 | |
129 | * 9 | +75 | +75 to +90 | |
130 | * 10 | +90 | +90 to +105 | |
131 | * 11 | +105 | +105 to +120 | |
132 | * 12 | +120 | +120 to +135 | |
133 | */ | |
134 | ||
135 | /* calculate thermal limitation */ | |
136 | min = (priv->comp * 15) - 60; | |
137 | max = min + 15; | |
138 | ||
139 | /* | |
140 | * we need to wait 300us after changing comparator offset | |
141 | * to get stable temperature. | |
142 | * see "Usage Notes" on datasheet | |
143 | */ | |
144 | rcar_thermal_bset(priv, THSCR, CPTAP, priv->comp); | |
145 | udelay(300); | |
146 | ||
147 | /* calculate current temperature */ | |
148 | val = rcar_thermal_read(priv, THSSR) & CTEMP; | |
149 | val = (val * 5) - 65; | |
150 | ||
151 | dev_dbg(priv->dev, "comp/min/max/val = %d/%d/%d/%d\n", | |
152 | priv->comp, min, max, val); | |
153 | ||
154 | /* | |
155 | * If val is same as min/max, then, | |
156 | * it should try again on next comparator. | |
157 | * But the val might be correct temperature. | |
158 | * Keep it on "tmp" and compare with next val. | |
159 | */ | |
160 | if (tmp == val) | |
161 | break; | |
162 | ||
163 | if (val <= min) { | |
164 | tmp = min; | |
165 | priv->comp--; /* try again */ | |
166 | } else if (val >= max) { | |
167 | tmp = max; | |
168 | priv->comp++; /* try again */ | |
169 | } else { | |
170 | tmp = val; | |
171 | break; | |
172 | } | |
173 | } | |
174 | ||
c499703e | 175 | *temp = MCELSIUS(tmp); |
1e426ffd KM |
176 | return 0; |
177 | } | |
178 | ||
179 | static struct thermal_zone_device_ops rcar_thermal_zone_ops = { | |
180 | .get_temp = rcar_thermal_get_temp, | |
181 | }; | |
182 | ||
183 | /* | |
184 | * platform functions | |
185 | */ | |
186 | static int rcar_thermal_probe(struct platform_device *pdev) | |
187 | { | |
188 | struct thermal_zone_device *zone; | |
189 | struct rcar_thermal_priv *priv; | |
190 | struct resource *res; | |
1e426ffd KM |
191 | |
192 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
193 | if (!res) { | |
194 | dev_err(&pdev->dev, "Could not get platform resource\n"); | |
195 | return -ENODEV; | |
196 | } | |
197 | ||
198 | priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); | |
199 | if (!priv) { | |
200 | dev_err(&pdev->dev, "Could not allocate priv\n"); | |
201 | return -ENOMEM; | |
202 | } | |
203 | ||
204 | priv->comp = 4; /* basic setup */ | |
205 | priv->dev = &pdev->dev; | |
206 | spin_lock_init(&priv->lock); | |
207 | priv->base = devm_ioremap_nocache(&pdev->dev, | |
208 | res->start, resource_size(res)); | |
209 | if (!priv->base) { | |
210 | dev_err(&pdev->dev, "Unable to ioremap thermal register\n"); | |
4e8e2f64 | 211 | return -ENOMEM; |
1e426ffd KM |
212 | } |
213 | ||
608f62b9 | 214 | zone = thermal_zone_device_register("rcar_thermal", 0, 0, priv, |
50125a9b | 215 | &rcar_thermal_zone_ops, NULL, 0, 0); |
1e426ffd KM |
216 | if (IS_ERR(zone)) { |
217 | dev_err(&pdev->dev, "thermal zone device is NULL\n"); | |
4e8e2f64 | 218 | return PTR_ERR(zone); |
1e426ffd KM |
219 | } |
220 | ||
221 | platform_set_drvdata(pdev, zone); | |
222 | ||
223 | dev_info(&pdev->dev, "proved\n"); | |
224 | ||
225 | return 0; | |
1e426ffd KM |
226 | } |
227 | ||
228 | static int rcar_thermal_remove(struct platform_device *pdev) | |
229 | { | |
230 | struct thermal_zone_device *zone = platform_get_drvdata(pdev); | |
1e426ffd KM |
231 | |
232 | thermal_zone_device_unregister(zone); | |
233 | platform_set_drvdata(pdev, NULL); | |
234 | ||
1e426ffd KM |
235 | return 0; |
236 | } | |
237 | ||
238 | static struct platform_driver rcar_thermal_driver = { | |
239 | .driver = { | |
240 | .name = "rcar_thermal", | |
241 | }, | |
242 | .probe = rcar_thermal_probe, | |
243 | .remove = rcar_thermal_remove, | |
244 | }; | |
245 | module_platform_driver(rcar_thermal_driver); | |
246 | ||
247 | MODULE_LICENSE("GPL"); | |
248 | MODULE_DESCRIPTION("R-Car THS/TSC thermal sensor driver"); | |
249 | MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>"); |