Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 1 | /* |
| 2 | * ntc_thermistor.c - NTC Thermistors |
| 3 | * |
| 4 | * Copyright (C) 2010 Samsung Electronics |
| 5 | * MyungJoo Ham <myungjoo.ham@samsung.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; either version 2 of the License, or |
| 10 | * (at your option) any later version. |
| 11 | * |
| 12 | * This program is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | * GNU General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License |
| 18 | * along with this program; if not, write to the Free Software |
| 19 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 20 | * |
| 21 | */ |
| 22 | |
| 23 | #include <linux/slab.h> |
| 24 | #include <linux/module.h> |
| 25 | #include <linux/pm_runtime.h> |
| 26 | #include <linux/math64.h> |
| 27 | #include <linux/platform_device.h> |
| 28 | #include <linux/err.h> |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 29 | #include <linux/of.h> |
| 30 | #include <linux/of_device.h> |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 31 | |
| 32 | #include <linux/platform_data/ntc_thermistor.h> |
| 33 | |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 34 | #include <linux/iio/iio.h> |
| 35 | #include <linux/iio/machine.h> |
| 36 | #include <linux/iio/driver.h> |
| 37 | #include <linux/iio/consumer.h> |
| 38 | |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 39 | #include <linux/hwmon.h> |
| 40 | #include <linux/hwmon-sysfs.h> |
| 41 | |
| 42 | struct ntc_compensation { |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 43 | int temp_c; |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 44 | unsigned int ohm; |
| 45 | }; |
| 46 | |
Jean Delvare | ead82d6 | 2014-05-25 17:23:08 +0200 | [diff] [blame] | 47 | /* Order matters, ntc_match references the entries by index */ |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 48 | static const struct platform_device_id ntc_thermistor_id[] = { |
| 49 | { "ncp15wb473", TYPE_NCPXXWB473 }, |
| 50 | { "ncp18wb473", TYPE_NCPXXWB473 }, |
| 51 | { "ncp21wb473", TYPE_NCPXXWB473 }, |
| 52 | { "ncp03wb473", TYPE_NCPXXWB473 }, |
| 53 | { "ncp15wl333", TYPE_NCPXXWL333 }, |
Johannes Pointner | ed67f08 | 2014-07-01 08:05:52 +0200 | [diff] [blame] | 54 | { "b57330v2103", TYPE_B57330V2103}, |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 55 | { }, |
| 56 | }; |
| 57 | |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 58 | /* |
| 59 | * A compensation table should be sorted by the values of .ohm |
| 60 | * in descending order. |
| 61 | * The following compensation tables are from the specification of Murata NTC |
| 62 | * Thermistors Datasheet |
| 63 | */ |
Sachin Kamat | 4626dcf | 2013-02-19 15:07:34 +0530 | [diff] [blame] | 64 | static const struct ntc_compensation ncpXXwb473[] = { |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 65 | { .temp_c = -40, .ohm = 1747920 }, |
| 66 | { .temp_c = -35, .ohm = 1245428 }, |
| 67 | { .temp_c = -30, .ohm = 898485 }, |
| 68 | { .temp_c = -25, .ohm = 655802 }, |
| 69 | { .temp_c = -20, .ohm = 483954 }, |
| 70 | { .temp_c = -15, .ohm = 360850 }, |
| 71 | { .temp_c = -10, .ohm = 271697 }, |
| 72 | { .temp_c = -5, .ohm = 206463 }, |
| 73 | { .temp_c = 0, .ohm = 158214 }, |
| 74 | { .temp_c = 5, .ohm = 122259 }, |
| 75 | { .temp_c = 10, .ohm = 95227 }, |
| 76 | { .temp_c = 15, .ohm = 74730 }, |
| 77 | { .temp_c = 20, .ohm = 59065 }, |
| 78 | { .temp_c = 25, .ohm = 47000 }, |
| 79 | { .temp_c = 30, .ohm = 37643 }, |
| 80 | { .temp_c = 35, .ohm = 30334 }, |
| 81 | { .temp_c = 40, .ohm = 24591 }, |
| 82 | { .temp_c = 45, .ohm = 20048 }, |
| 83 | { .temp_c = 50, .ohm = 16433 }, |
| 84 | { .temp_c = 55, .ohm = 13539 }, |
| 85 | { .temp_c = 60, .ohm = 11209 }, |
| 86 | { .temp_c = 65, .ohm = 9328 }, |
| 87 | { .temp_c = 70, .ohm = 7798 }, |
| 88 | { .temp_c = 75, .ohm = 6544 }, |
| 89 | { .temp_c = 80, .ohm = 5518 }, |
| 90 | { .temp_c = 85, .ohm = 4674 }, |
| 91 | { .temp_c = 90, .ohm = 3972 }, |
| 92 | { .temp_c = 95, .ohm = 3388 }, |
| 93 | { .temp_c = 100, .ohm = 2902 }, |
| 94 | { .temp_c = 105, .ohm = 2494 }, |
| 95 | { .temp_c = 110, .ohm = 2150 }, |
| 96 | { .temp_c = 115, .ohm = 1860 }, |
| 97 | { .temp_c = 120, .ohm = 1615 }, |
| 98 | { .temp_c = 125, .ohm = 1406 }, |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 99 | }; |
Sachin Kamat | 4626dcf | 2013-02-19 15:07:34 +0530 | [diff] [blame] | 100 | static const struct ntc_compensation ncpXXwl333[] = { |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 101 | { .temp_c = -40, .ohm = 1610154 }, |
| 102 | { .temp_c = -35, .ohm = 1130850 }, |
| 103 | { .temp_c = -30, .ohm = 802609 }, |
| 104 | { .temp_c = -25, .ohm = 575385 }, |
| 105 | { .temp_c = -20, .ohm = 416464 }, |
| 106 | { .temp_c = -15, .ohm = 304219 }, |
| 107 | { .temp_c = -10, .ohm = 224193 }, |
| 108 | { .temp_c = -5, .ohm = 166623 }, |
| 109 | { .temp_c = 0, .ohm = 124850 }, |
| 110 | { .temp_c = 5, .ohm = 94287 }, |
| 111 | { .temp_c = 10, .ohm = 71747 }, |
| 112 | { .temp_c = 15, .ohm = 54996 }, |
| 113 | { .temp_c = 20, .ohm = 42455 }, |
| 114 | { .temp_c = 25, .ohm = 33000 }, |
| 115 | { .temp_c = 30, .ohm = 25822 }, |
| 116 | { .temp_c = 35, .ohm = 20335 }, |
| 117 | { .temp_c = 40, .ohm = 16115 }, |
| 118 | { .temp_c = 45, .ohm = 12849 }, |
| 119 | { .temp_c = 50, .ohm = 10306 }, |
| 120 | { .temp_c = 55, .ohm = 8314 }, |
| 121 | { .temp_c = 60, .ohm = 6746 }, |
| 122 | { .temp_c = 65, .ohm = 5503 }, |
| 123 | { .temp_c = 70, .ohm = 4513 }, |
| 124 | { .temp_c = 75, .ohm = 3721 }, |
| 125 | { .temp_c = 80, .ohm = 3084 }, |
| 126 | { .temp_c = 85, .ohm = 2569 }, |
| 127 | { .temp_c = 90, .ohm = 2151 }, |
| 128 | { .temp_c = 95, .ohm = 1809 }, |
| 129 | { .temp_c = 100, .ohm = 1529 }, |
| 130 | { .temp_c = 105, .ohm = 1299 }, |
| 131 | { .temp_c = 110, .ohm = 1108 }, |
| 132 | { .temp_c = 115, .ohm = 949 }, |
| 133 | { .temp_c = 120, .ohm = 817 }, |
| 134 | { .temp_c = 125, .ohm = 707 }, |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 135 | }; |
| 136 | |
Johannes Pointner | ed67f08 | 2014-07-01 08:05:52 +0200 | [diff] [blame] | 137 | /* |
| 138 | * The following compensation table is from the specification of EPCOS NTC |
| 139 | * Thermistors Datasheet |
| 140 | */ |
| 141 | static const struct ntc_compensation b57330v2103[] = { |
| 142 | { .temp_c = -40, .ohm = 190030 }, |
| 143 | { .temp_c = -35, .ohm = 145360 }, |
| 144 | { .temp_c = -30, .ohm = 112060 }, |
| 145 | { .temp_c = -25, .ohm = 87041 }, |
| 146 | { .temp_c = -20, .ohm = 68104 }, |
| 147 | { .temp_c = -15, .ohm = 53665 }, |
| 148 | { .temp_c = -10, .ohm = 42576 }, |
| 149 | { .temp_c = -5, .ohm = 34001 }, |
| 150 | { .temp_c = 0, .ohm = 27326 }, |
| 151 | { .temp_c = 5, .ohm = 22096 }, |
| 152 | { .temp_c = 10, .ohm = 17973 }, |
| 153 | { .temp_c = 15, .ohm = 14703 }, |
| 154 | { .temp_c = 20, .ohm = 12090 }, |
| 155 | { .temp_c = 25, .ohm = 10000 }, |
| 156 | { .temp_c = 30, .ohm = 8311 }, |
| 157 | { .temp_c = 35, .ohm = 6941 }, |
| 158 | { .temp_c = 40, .ohm = 5825 }, |
| 159 | { .temp_c = 45, .ohm = 4911 }, |
| 160 | { .temp_c = 50, .ohm = 4158 }, |
| 161 | { .temp_c = 55, .ohm = 3536 }, |
| 162 | { .temp_c = 60, .ohm = 3019 }, |
| 163 | { .temp_c = 65, .ohm = 2588 }, |
| 164 | { .temp_c = 70, .ohm = 2227 }, |
| 165 | { .temp_c = 75, .ohm = 1924 }, |
| 166 | { .temp_c = 80, .ohm = 1668 }, |
| 167 | { .temp_c = 85, .ohm = 1451 }, |
| 168 | { .temp_c = 90, .ohm = 1266 }, |
| 169 | { .temp_c = 95, .ohm = 1108 }, |
| 170 | { .temp_c = 100, .ohm = 973 }, |
| 171 | { .temp_c = 105, .ohm = 857 }, |
| 172 | { .temp_c = 110, .ohm = 757 }, |
| 173 | { .temp_c = 115, .ohm = 671 }, |
| 174 | { .temp_c = 120, .ohm = 596 }, |
| 175 | { .temp_c = 125, .ohm = 531 }, |
| 176 | }; |
| 177 | |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 178 | struct ntc_data { |
| 179 | struct device *hwmon_dev; |
| 180 | struct ntc_thermistor_platform_data *pdata; |
| 181 | const struct ntc_compensation *comp; |
| 182 | struct device *dev; |
| 183 | int n_comp; |
| 184 | char name[PLATFORM_NAME_SIZE]; |
| 185 | }; |
| 186 | |
Jean Delvare | 59cf424 | 2014-05-25 17:23:08 +0200 | [diff] [blame] | 187 | #if defined(CONFIG_OF) && IS_ENABLED(CONFIG_IIO) |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 188 | static int ntc_adc_iio_read(struct ntc_thermistor_platform_data *pdata) |
| 189 | { |
| 190 | struct iio_channel *channel = pdata->chan; |
Doug Anderson | d3d89c4 | 2014-02-13 14:39:34 -0800 | [diff] [blame] | 191 | s64 result; |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 192 | int val, ret; |
| 193 | |
| 194 | ret = iio_read_channel_raw(channel, &val); |
| 195 | if (ret < 0) { |
| 196 | pr_err("read channel() error: %d\n", ret); |
| 197 | return ret; |
| 198 | } |
| 199 | |
| 200 | /* unit: mV */ |
Doug Anderson | d3d89c4 | 2014-02-13 14:39:34 -0800 | [diff] [blame] | 201 | result = pdata->pullup_uv * (s64) val; |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 202 | result >>= 12; |
| 203 | |
Doug Anderson | d3d89c4 | 2014-02-13 14:39:34 -0800 | [diff] [blame] | 204 | return (int)result; |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 205 | } |
| 206 | |
| 207 | static const struct of_device_id ntc_match[] = { |
Naveen Krishna Chatradhi | 8b6f5e0 | 2014-06-25 11:59:31 +0530 | [diff] [blame] | 208 | { .compatible = "murata,ncp15wb473", |
| 209 | .data = &ntc_thermistor_id[0] }, |
| 210 | { .compatible = "murata,ncp18wb473", |
| 211 | .data = &ntc_thermistor_id[1] }, |
| 212 | { .compatible = "murata,ncp21wb473", |
| 213 | .data = &ntc_thermistor_id[2] }, |
| 214 | { .compatible = "murata,ncp03wb473", |
| 215 | .data = &ntc_thermistor_id[3] }, |
| 216 | { .compatible = "murata,ncp15wl333", |
| 217 | .data = &ntc_thermistor_id[4] }, |
Johannes Pointner | ed67f08 | 2014-07-01 08:05:52 +0200 | [diff] [blame] | 218 | { .compatible = "epcos,b57330v2103", |
| 219 | .data = &ntc_thermistor_id[5]}, |
Naveen Krishna Chatradhi | 8b6f5e0 | 2014-06-25 11:59:31 +0530 | [diff] [blame] | 220 | |
| 221 | /* Usage of vendor name "ntc" is deprecated */ |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 222 | { .compatible = "ntc,ncp15wb473", |
Jean Delvare | ead82d6 | 2014-05-25 17:23:08 +0200 | [diff] [blame] | 223 | .data = &ntc_thermistor_id[0] }, |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 224 | { .compatible = "ntc,ncp18wb473", |
Jean Delvare | ead82d6 | 2014-05-25 17:23:08 +0200 | [diff] [blame] | 225 | .data = &ntc_thermistor_id[1] }, |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 226 | { .compatible = "ntc,ncp21wb473", |
Jean Delvare | ead82d6 | 2014-05-25 17:23:08 +0200 | [diff] [blame] | 227 | .data = &ntc_thermistor_id[2] }, |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 228 | { .compatible = "ntc,ncp03wb473", |
Jean Delvare | ead82d6 | 2014-05-25 17:23:08 +0200 | [diff] [blame] | 229 | .data = &ntc_thermistor_id[3] }, |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 230 | { .compatible = "ntc,ncp15wl333", |
Jean Delvare | ead82d6 | 2014-05-25 17:23:08 +0200 | [diff] [blame] | 231 | .data = &ntc_thermistor_id[4] }, |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 232 | { }, |
| 233 | }; |
| 234 | MODULE_DEVICE_TABLE(of, ntc_match); |
| 235 | |
| 236 | static struct ntc_thermistor_platform_data * |
| 237 | ntc_thermistor_parse_dt(struct platform_device *pdev) |
| 238 | { |
| 239 | struct iio_channel *chan; |
| 240 | struct device_node *np = pdev->dev.of_node; |
| 241 | struct ntc_thermistor_platform_data *pdata; |
| 242 | |
| 243 | if (!np) |
| 244 | return NULL; |
| 245 | |
| 246 | pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); |
| 247 | if (!pdata) |
| 248 | return ERR_PTR(-ENOMEM); |
| 249 | |
| 250 | chan = iio_channel_get(&pdev->dev, NULL); |
| 251 | if (IS_ERR(chan)) |
| 252 | return ERR_CAST(chan); |
| 253 | |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 254 | if (of_property_read_u32(np, "pullup-uv", &pdata->pullup_uv)) |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 255 | return ERR_PTR(-ENODEV); |
| 256 | if (of_property_read_u32(np, "pullup-ohm", &pdata->pullup_ohm)) |
| 257 | return ERR_PTR(-ENODEV); |
| 258 | if (of_property_read_u32(np, "pulldown-ohm", &pdata->pulldown_ohm)) |
| 259 | return ERR_PTR(-ENODEV); |
| 260 | |
| 261 | if (of_find_property(np, "connected-positive", NULL)) |
| 262 | pdata->connect = NTC_CONNECTED_POSITIVE; |
| 263 | else /* status change should be possible if not always on. */ |
| 264 | pdata->connect = NTC_CONNECTED_GROUND; |
| 265 | |
| 266 | pdata->chan = chan; |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 267 | pdata->read_uv = ntc_adc_iio_read; |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 268 | |
| 269 | return pdata; |
| 270 | } |
| 271 | static void ntc_iio_channel_release(struct ntc_thermistor_platform_data *pdata) |
| 272 | { |
| 273 | if (pdata->chan) |
| 274 | iio_channel_release(pdata->chan); |
| 275 | } |
| 276 | #else |
| 277 | static struct ntc_thermistor_platform_data * |
| 278 | ntc_thermistor_parse_dt(struct platform_device *pdev) |
| 279 | { |
| 280 | return NULL; |
| 281 | } |
| 282 | |
Jean Delvare | 59cf424 | 2014-05-25 17:23:08 +0200 | [diff] [blame] | 283 | #define ntc_match NULL |
| 284 | |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 285 | static void ntc_iio_channel_release(struct ntc_thermistor_platform_data *pdata) |
| 286 | { } |
| 287 | #endif |
| 288 | |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 289 | static inline u64 div64_u64_safe(u64 dividend, u64 divisor) |
| 290 | { |
| 291 | if (divisor == 0 && dividend == 0) |
| 292 | return 0; |
| 293 | if (divisor == 0) |
| 294 | return UINT_MAX; |
| 295 | return div64_u64(dividend, divisor); |
| 296 | } |
| 297 | |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 298 | static int get_ohm_of_thermistor(struct ntc_data *data, unsigned int uv) |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 299 | { |
| 300 | struct ntc_thermistor_platform_data *pdata = data->pdata; |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 301 | u64 mv = uv / 1000; |
| 302 | u64 pmv = pdata->pullup_uv / 1000; |
| 303 | u64 n, puo, pdo; |
| 304 | puo = pdata->pullup_ohm; |
| 305 | pdo = pdata->pulldown_ohm; |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 306 | |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 307 | if (mv == 0) { |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 308 | if (pdata->connect == NTC_CONNECTED_POSITIVE) |
Guenter Roeck | dbe43a6 | 2012-04-22 20:58:51 -0700 | [diff] [blame] | 309 | return INT_MAX; |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 310 | return 0; |
| 311 | } |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 312 | if (mv >= pmv) |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 313 | return (pdata->connect == NTC_CONNECTED_POSITIVE) ? |
Guenter Roeck | dbe43a6 | 2012-04-22 20:58:51 -0700 | [diff] [blame] | 314 | 0 : INT_MAX; |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 315 | |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 316 | if (pdata->connect == NTC_CONNECTED_POSITIVE && puo == 0) |
| 317 | n = div64_u64_safe(pdo * (pmv - mv), mv); |
| 318 | else if (pdata->connect == NTC_CONNECTED_GROUND && pdo == 0) |
| 319 | n = div64_u64_safe(puo * mv, pmv - mv); |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 320 | else if (pdata->connect == NTC_CONNECTED_POSITIVE) |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 321 | n = div64_u64_safe(pdo * puo * (pmv - mv), |
| 322 | puo * mv - pdo * (pmv - mv)); |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 323 | else |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 324 | n = div64_u64_safe(pdo * puo * mv, pdo * (pmv - mv) - puo * mv); |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 325 | |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 326 | if (n > INT_MAX) |
| 327 | n = INT_MAX; |
| 328 | return n; |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 329 | } |
| 330 | |
Guenter Roeck | dbe43a6 | 2012-04-22 20:58:51 -0700 | [diff] [blame] | 331 | static void lookup_comp(struct ntc_data *data, unsigned int ohm, |
| 332 | int *i_low, int *i_high) |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 333 | { |
Guenter Roeck | dbe43a6 | 2012-04-22 20:58:51 -0700 | [diff] [blame] | 334 | int start, end, mid; |
| 335 | |
| 336 | /* |
| 337 | * Handle special cases: Resistance is higher than or equal to |
| 338 | * resistance in first table entry, or resistance is lower or equal |
| 339 | * to resistance in last table entry. |
| 340 | * In these cases, return i_low == i_high, either pointing to the |
| 341 | * beginning or to the end of the table depending on the condition. |
| 342 | */ |
| 343 | if (ohm >= data->comp[0].ohm) { |
| 344 | *i_low = 0; |
| 345 | *i_high = 0; |
| 346 | return; |
| 347 | } |
| 348 | if (ohm <= data->comp[data->n_comp - 1].ohm) { |
| 349 | *i_low = data->n_comp - 1; |
| 350 | *i_high = data->n_comp - 1; |
| 351 | return; |
| 352 | } |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 353 | |
| 354 | /* Do a binary search on compensation table */ |
| 355 | start = 0; |
| 356 | end = data->n_comp; |
Guenter Roeck | dbe43a6 | 2012-04-22 20:58:51 -0700 | [diff] [blame] | 357 | while (start < end) { |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 358 | mid = start + (end - start) / 2; |
Guenter Roeck | dbe43a6 | 2012-04-22 20:58:51 -0700 | [diff] [blame] | 359 | /* |
| 360 | * start <= mid < end |
| 361 | * data->comp[start].ohm > ohm >= data->comp[end].ohm |
| 362 | * |
| 363 | * We could check for "ohm == data->comp[mid].ohm" here, but |
| 364 | * that is a quite unlikely condition, and we would have to |
| 365 | * check again after updating start. Check it at the end instead |
| 366 | * for simplicity. |
| 367 | */ |
| 368 | if (ohm >= data->comp[mid].ohm) { |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 369 | end = mid; |
Guenter Roeck | dbe43a6 | 2012-04-22 20:58:51 -0700 | [diff] [blame] | 370 | } else { |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 371 | start = mid + 1; |
Guenter Roeck | dbe43a6 | 2012-04-22 20:58:51 -0700 | [diff] [blame] | 372 | /* |
| 373 | * ohm >= data->comp[start].ohm might be true here, |
| 374 | * since we set start to mid + 1. In that case, we are |
| 375 | * done. We could keep going, but the condition is quite |
| 376 | * likely to occur, so it is worth checking for it. |
| 377 | */ |
| 378 | if (ohm >= data->comp[start].ohm) |
| 379 | end = start; |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 380 | } |
Guenter Roeck | dbe43a6 | 2012-04-22 20:58:51 -0700 | [diff] [blame] | 381 | /* |
| 382 | * start <= end |
| 383 | * data->comp[start].ohm >= ohm >= data->comp[end].ohm |
| 384 | */ |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 385 | } |
Guenter Roeck | dbe43a6 | 2012-04-22 20:58:51 -0700 | [diff] [blame] | 386 | /* |
| 387 | * start == end |
| 388 | * ohm >= data->comp[end].ohm |
| 389 | */ |
| 390 | *i_low = end; |
| 391 | if (ohm == data->comp[end].ohm) |
| 392 | *i_high = end; |
| 393 | else |
| 394 | *i_high = end - 1; |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 395 | } |
| 396 | |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 397 | static int get_temp_mc(struct ntc_data *data, unsigned int ohm) |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 398 | { |
| 399 | int low, high; |
Guenter Roeck | dbe43a6 | 2012-04-22 20:58:51 -0700 | [diff] [blame] | 400 | int temp; |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 401 | |
Guenter Roeck | dbe43a6 | 2012-04-22 20:58:51 -0700 | [diff] [blame] | 402 | lookup_comp(data, ohm, &low, &high); |
| 403 | if (low == high) { |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 404 | /* Unable to use linear approximation */ |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 405 | temp = data->comp[low].temp_c * 1000; |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 406 | } else { |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 407 | temp = data->comp[low].temp_c * 1000 + |
| 408 | ((data->comp[high].temp_c - data->comp[low].temp_c) * |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 409 | 1000 * ((int)ohm - (int)data->comp[low].ohm)) / |
| 410 | ((int)data->comp[high].ohm - (int)data->comp[low].ohm); |
| 411 | } |
Guenter Roeck | dbe43a6 | 2012-04-22 20:58:51 -0700 | [diff] [blame] | 412 | return temp; |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 413 | } |
| 414 | |
Guenter Roeck | dbe43a6 | 2012-04-22 20:58:51 -0700 | [diff] [blame] | 415 | static int ntc_thermistor_get_ohm(struct ntc_data *data) |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 416 | { |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 417 | int read_uv; |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 418 | |
Guenter Roeck | dbe43a6 | 2012-04-22 20:58:51 -0700 | [diff] [blame] | 419 | if (data->pdata->read_ohm) |
| 420 | return data->pdata->read_ohm(); |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 421 | |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 422 | if (data->pdata->read_uv) { |
| 423 | read_uv = data->pdata->read_uv(data->pdata); |
| 424 | if (read_uv < 0) |
| 425 | return read_uv; |
| 426 | return get_ohm_of_thermistor(data, read_uv); |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 427 | } |
Guenter Roeck | dbe43a6 | 2012-04-22 20:58:51 -0700 | [diff] [blame] | 428 | return -EINVAL; |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 429 | } |
| 430 | |
| 431 | static ssize_t ntc_show_name(struct device *dev, |
| 432 | struct device_attribute *attr, char *buf) |
| 433 | { |
| 434 | struct ntc_data *data = dev_get_drvdata(dev); |
| 435 | |
| 436 | return sprintf(buf, "%s\n", data->name); |
| 437 | } |
| 438 | |
| 439 | static ssize_t ntc_show_type(struct device *dev, |
| 440 | struct device_attribute *attr, char *buf) |
| 441 | { |
| 442 | return sprintf(buf, "4\n"); |
| 443 | } |
| 444 | |
| 445 | static ssize_t ntc_show_temp(struct device *dev, |
| 446 | struct device_attribute *attr, char *buf) |
| 447 | { |
| 448 | struct ntc_data *data = dev_get_drvdata(dev); |
Guenter Roeck | dbe43a6 | 2012-04-22 20:58:51 -0700 | [diff] [blame] | 449 | int ohm; |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 450 | |
Guenter Roeck | dbe43a6 | 2012-04-22 20:58:51 -0700 | [diff] [blame] | 451 | ohm = ntc_thermistor_get_ohm(data); |
| 452 | if (ohm < 0) |
| 453 | return ohm; |
| 454 | |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 455 | return sprintf(buf, "%d\n", get_temp_mc(data, ohm)); |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 456 | } |
| 457 | |
| 458 | static SENSOR_DEVICE_ATTR(temp1_type, S_IRUGO, ntc_show_type, NULL, 0); |
| 459 | static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, ntc_show_temp, NULL, 0); |
| 460 | static DEVICE_ATTR(name, S_IRUGO, ntc_show_name, NULL); |
| 461 | |
| 462 | static struct attribute *ntc_attributes[] = { |
| 463 | &dev_attr_name.attr, |
| 464 | &sensor_dev_attr_temp1_type.dev_attr.attr, |
| 465 | &sensor_dev_attr_temp1_input.dev_attr.attr, |
| 466 | NULL, |
| 467 | }; |
| 468 | |
| 469 | static const struct attribute_group ntc_attr_group = { |
| 470 | .attrs = ntc_attributes, |
| 471 | }; |
| 472 | |
Bill Pemberton | 6c931ae | 2012-11-19 13:22:35 -0500 | [diff] [blame] | 473 | static int ntc_thermistor_probe(struct platform_device *pdev) |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 474 | { |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 475 | const struct of_device_id *of_id = |
| 476 | of_match_device(of_match_ptr(ntc_match), &pdev->dev); |
| 477 | const struct platform_device_id *pdev_id; |
| 478 | struct ntc_thermistor_platform_data *pdata; |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 479 | struct ntc_data *data; |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 480 | int ret; |
| 481 | |
| 482 | pdata = ntc_thermistor_parse_dt(pdev); |
| 483 | if (IS_ERR(pdata)) |
| 484 | return PTR_ERR(pdata); |
| 485 | else if (pdata == NULL) |
Jingoo Han | a8b3a3a | 2013-07-30 17:13:06 +0900 | [diff] [blame] | 486 | pdata = dev_get_platdata(&pdev->dev); |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 487 | |
| 488 | if (!pdata) { |
| 489 | dev_err(&pdev->dev, "No platform init data supplied.\n"); |
| 490 | return -ENODEV; |
| 491 | } |
| 492 | |
| 493 | /* Either one of the two is required. */ |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 494 | if (!pdata->read_uv && !pdata->read_ohm) { |
Guenter Roeck | a7871de | 2012-04-23 10:33:45 -0700 | [diff] [blame] | 495 | dev_err(&pdev->dev, |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 496 | "Both read_uv and read_ohm missing. Need either one of the two.\n"); |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 497 | return -EINVAL; |
| 498 | } |
| 499 | |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 500 | if (pdata->read_uv && pdata->read_ohm) { |
Guenter Roeck | a7871de | 2012-04-23 10:33:45 -0700 | [diff] [blame] | 501 | dev_warn(&pdev->dev, |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 502 | "Only one of read_uv and read_ohm is needed; ignoring read_uv.\n"); |
| 503 | pdata->read_uv = NULL; |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 504 | } |
| 505 | |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 506 | if (pdata->read_uv && (pdata->pullup_uv == 0 || |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 507 | (pdata->pullup_ohm == 0 && pdata->connect == |
| 508 | NTC_CONNECTED_GROUND) || |
| 509 | (pdata->pulldown_ohm == 0 && pdata->connect == |
| 510 | NTC_CONNECTED_POSITIVE) || |
| 511 | (pdata->connect != NTC_CONNECTED_POSITIVE && |
| 512 | pdata->connect != NTC_CONNECTED_GROUND))) { |
Guenter Roeck | a7871de | 2012-04-23 10:33:45 -0700 | [diff] [blame] | 513 | dev_err(&pdev->dev, |
Guenter Roeck | 088ce2a | 2013-03-13 16:40:39 -0700 | [diff] [blame] | 514 | "Required data to use read_uv not supplied.\n"); |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 515 | return -EINVAL; |
| 516 | } |
| 517 | |
Guenter Roeck | 41141e6 | 2012-04-23 10:39:00 -0700 | [diff] [blame] | 518 | data = devm_kzalloc(&pdev->dev, sizeof(struct ntc_data), GFP_KERNEL); |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 519 | if (!data) |
| 520 | return -ENOMEM; |
| 521 | |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 522 | pdev_id = of_id ? of_id->data : platform_get_device_id(pdev); |
| 523 | |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 524 | data->dev = &pdev->dev; |
| 525 | data->pdata = pdata; |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 526 | strlcpy(data->name, pdev_id->name, sizeof(data->name)); |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 527 | |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 528 | switch (pdev_id->driver_data) { |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 529 | case TYPE_NCPXXWB473: |
| 530 | data->comp = ncpXXwb473; |
| 531 | data->n_comp = ARRAY_SIZE(ncpXXwb473); |
| 532 | break; |
| 533 | case TYPE_NCPXXWL333: |
| 534 | data->comp = ncpXXwl333; |
| 535 | data->n_comp = ARRAY_SIZE(ncpXXwl333); |
| 536 | break; |
Johannes Pointner | ed67f08 | 2014-07-01 08:05:52 +0200 | [diff] [blame] | 537 | case TYPE_B57330V2103: |
| 538 | data->comp = b57330v2103; |
| 539 | data->n_comp = ARRAY_SIZE(b57330v2103); |
| 540 | break; |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 541 | default: |
| 542 | dev_err(&pdev->dev, "Unknown device type: %lu(%s)\n", |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 543 | pdev_id->driver_data, pdev_id->name); |
Guenter Roeck | 41141e6 | 2012-04-23 10:39:00 -0700 | [diff] [blame] | 544 | return -EINVAL; |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 545 | } |
| 546 | |
| 547 | platform_set_drvdata(pdev, data); |
| 548 | |
| 549 | ret = sysfs_create_group(&data->dev->kobj, &ntc_attr_group); |
| 550 | if (ret) { |
| 551 | dev_err(data->dev, "unable to create sysfs files\n"); |
Guenter Roeck | 41141e6 | 2012-04-23 10:39:00 -0700 | [diff] [blame] | 552 | return ret; |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 553 | } |
| 554 | |
| 555 | data->hwmon_dev = hwmon_device_register(data->dev); |
Guenter Roeck | 425d247 | 2012-04-23 10:41:03 -0700 | [diff] [blame] | 556 | if (IS_ERR(data->hwmon_dev)) { |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 557 | dev_err(data->dev, "unable to register as hwmon device.\n"); |
Guenter Roeck | 425d247 | 2012-04-23 10:41:03 -0700 | [diff] [blame] | 558 | ret = PTR_ERR(data->hwmon_dev); |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 559 | goto err_after_sysfs; |
| 560 | } |
| 561 | |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 562 | dev_info(&pdev->dev, "Thermistor type: %s successfully probed.\n", |
Naveen Krishna Chatradhi | 93a88ef | 2014-06-26 18:20:14 +0530 | [diff] [blame] | 563 | pdev_id->name); |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 564 | |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 565 | return 0; |
| 566 | err_after_sysfs: |
| 567 | sysfs_remove_group(&data->dev->kobj, &ntc_attr_group); |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 568 | ntc_iio_channel_release(pdata); |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 569 | return ret; |
| 570 | } |
| 571 | |
Bill Pemberton | 281dfd0 | 2012-11-19 13:25:51 -0500 | [diff] [blame] | 572 | static int ntc_thermistor_remove(struct platform_device *pdev) |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 573 | { |
| 574 | struct ntc_data *data = platform_get_drvdata(pdev); |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 575 | struct ntc_thermistor_platform_data *pdata = data->pdata; |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 576 | |
| 577 | hwmon_device_unregister(data->hwmon_dev); |
| 578 | sysfs_remove_group(&data->dev->kobj, &ntc_attr_group); |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 579 | ntc_iio_channel_release(pdata); |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 580 | |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 581 | return 0; |
| 582 | } |
| 583 | |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 584 | static struct platform_driver ntc_thermistor_driver = { |
| 585 | .driver = { |
| 586 | .name = "ntc-thermistor", |
| 587 | .owner = THIS_MODULE, |
Naveen Krishna Chatradhi | 9e8269d | 2013-03-13 09:38:20 +0530 | [diff] [blame] | 588 | .of_match_table = of_match_ptr(ntc_match), |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 589 | }, |
| 590 | .probe = ntc_thermistor_probe, |
Bill Pemberton | 9e5e9b7 | 2012-11-19 13:21:20 -0500 | [diff] [blame] | 591 | .remove = ntc_thermistor_remove, |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 592 | .id_table = ntc_thermistor_id, |
| 593 | }; |
| 594 | |
Axel Lin | 25a236a | 2011-11-25 02:31:00 -0500 | [diff] [blame] | 595 | module_platform_driver(ntc_thermistor_driver); |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 596 | |
Johannes Pointner | ed67f08 | 2014-07-01 08:05:52 +0200 | [diff] [blame] | 597 | MODULE_DESCRIPTION("NTC Thermistor Driver"); |
Donggeun Kim | f22aaaa | 2011-06-20 16:48:19 +0900 | [diff] [blame] | 598 | MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>"); |
| 599 | MODULE_LICENSE("GPL"); |
| 600 | MODULE_ALIAS("platform:ntc-thermistor"); |