1 /* 2 * HID Sensor Time Driver 3 * Copyright (c) 2012, Alexander Holler. 4 * 5 * This program is free software; you can redistribute it and/or modify it 6 * under the terms and conditions of the GNU General Public License, 7 * version 2, as published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 12 * more details. 13 * 14 * You should have received a copy of the GNU General Public License along with 15 * this program; if not, write to the Free Software Foundation, Inc., 16 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. 17 * 18 */ 19 #include <linux/device.h> 20 #include <linux/platform_device.h> 21 #include <linux/module.h> 22 #include <linux/hid-sensor-hub.h> 23 #include <linux/iio/iio.h> 24 #include <linux/rtc.h> 25 26 enum hid_time_channel { 27 CHANNEL_SCAN_INDEX_YEAR, 28 CHANNEL_SCAN_INDEX_MONTH, 29 CHANNEL_SCAN_INDEX_DAY, 30 CHANNEL_SCAN_INDEX_HOUR, 31 CHANNEL_SCAN_INDEX_MINUTE, 32 CHANNEL_SCAN_INDEX_SECOND, 33 TIME_RTC_CHANNEL_MAX, 34 }; 35 36 struct hid_time_state { 37 struct hid_sensor_hub_callbacks callbacks; 38 struct hid_sensor_common common_attributes; 39 struct hid_sensor_hub_attribute_info info[TIME_RTC_CHANNEL_MAX]; 40 struct rtc_time last_time; 41 spinlock_t lock_last_time; 42 struct completion comp_last_time; 43 struct rtc_time time_buf; 44 struct rtc_device *rtc; 45 }; 46 47 static const u32 hid_time_addresses[TIME_RTC_CHANNEL_MAX] = { 48 HID_USAGE_SENSOR_TIME_YEAR, 49 HID_USAGE_SENSOR_TIME_MONTH, 50 HID_USAGE_SENSOR_TIME_DAY, 51 HID_USAGE_SENSOR_TIME_HOUR, 52 HID_USAGE_SENSOR_TIME_MINUTE, 53 HID_USAGE_SENSOR_TIME_SECOND, 54 }; 55 56 /* Channel names for verbose error messages */ 57 static const char * const hid_time_channel_names[TIME_RTC_CHANNEL_MAX] = { 58 "year", "month", "day", "hour", "minute", "second", 59 }; 60 61 /* Callback handler to send event after all samples are received and captured */ 62 static int hid_time_proc_event(struct hid_sensor_hub_device *hsdev, 63 unsigned usage_id, void *priv) 64 { 65 unsigned long flags; 66 struct hid_time_state *time_state = platform_get_drvdata(priv); 67 68 spin_lock_irqsave(&time_state->lock_last_time, flags); 69 time_state->last_time = time_state->time_buf; 70 spin_unlock_irqrestore(&time_state->lock_last_time, flags); 71 complete(&time_state->comp_last_time); 72 return 0; 73 } 74 75 static u32 hid_time_value(size_t raw_len, char *raw_data) 76 { 77 switch (raw_len) { 78 case 1: 79 return *(u8 *)raw_data; 80 case 2: 81 return *(u16 *)raw_data; 82 case 4: 83 return *(u32 *)raw_data; 84 default: 85 return (u32)(~0U); /* 0xff... or -1 to denote an error */ 86 } 87 } 88 89 static int hid_time_capture_sample(struct hid_sensor_hub_device *hsdev, 90 unsigned usage_id, size_t raw_len, 91 char *raw_data, void *priv) 92 { 93 struct hid_time_state *time_state = platform_get_drvdata(priv); 94 struct rtc_time *time_buf = &time_state->time_buf; 95 96 switch (usage_id) { 97 case HID_USAGE_SENSOR_TIME_YEAR: 98 /* 99 * The draft for HID-sensors (HUTRR39) currently doesn't define 100 * the range for the year attribute. Therefor we support 101 * 8 bit (0-99) and 16 or 32 bits (full) as size for the year. 102 */ 103 if (raw_len == 1) { 104 time_buf->tm_year = *(u8 *)raw_data; 105 if (time_buf->tm_year < 70) 106 /* assume we are in 1970...2069 */ 107 time_buf->tm_year += 100; 108 } else 109 time_buf->tm_year = 110 (int)hid_time_value(raw_len, raw_data)-1900; 111 break; 112 case HID_USAGE_SENSOR_TIME_MONTH: 113 /* sensors are sending the month as 1-12, we need 0-11 */ 114 time_buf->tm_mon = (int)hid_time_value(raw_len, raw_data)-1; 115 break; 116 case HID_USAGE_SENSOR_TIME_DAY: 117 time_buf->tm_mday = (int)hid_time_value(raw_len, raw_data); 118 break; 119 case HID_USAGE_SENSOR_TIME_HOUR: 120 time_buf->tm_hour = (int)hid_time_value(raw_len, raw_data); 121 break; 122 case HID_USAGE_SENSOR_TIME_MINUTE: 123 time_buf->tm_min = (int)hid_time_value(raw_len, raw_data); 124 break; 125 case HID_USAGE_SENSOR_TIME_SECOND: 126 time_buf->tm_sec = (int)hid_time_value(raw_len, raw_data); 127 break; 128 default: 129 return -EINVAL; 130 } 131 return 0; 132 } 133 134 /* small helper, haven't found any other way */ 135 static const char *hid_time_attrib_name(u32 attrib_id) 136 { 137 static const char unknown[] = "unknown"; 138 unsigned i; 139 140 for (i = 0; i < TIME_RTC_CHANNEL_MAX; ++i) { 141 if (hid_time_addresses[i] == attrib_id) 142 return hid_time_channel_names[i]; 143 } 144 return unknown; /* should never happen */ 145 } 146 147 static int hid_time_parse_report(struct platform_device *pdev, 148 struct hid_sensor_hub_device *hsdev, 149 unsigned usage_id, 150 struct hid_time_state *time_state) 151 { 152 int report_id, i; 153 154 for (i = 0; i < TIME_RTC_CHANNEL_MAX; ++i) 155 if (sensor_hub_input_get_attribute_info(hsdev, 156 HID_INPUT_REPORT, usage_id, 157 hid_time_addresses[i], 158 &time_state->info[i]) < 0) 159 return -EINVAL; 160 /* Check the (needed) attributes for sanity */ 161 report_id = time_state->info[0].report_id; 162 if (report_id < 0) { 163 dev_err(&pdev->dev, "bad report ID!\n"); 164 return -EINVAL; 165 } 166 for (i = 0; i < TIME_RTC_CHANNEL_MAX; ++i) { 167 if (time_state->info[i].report_id != report_id) { 168 dev_err(&pdev->dev, 169 "not all needed attributes inside the same report!\n"); 170 return -EINVAL; 171 } 172 if (time_state->info[i].size == 3 || 173 time_state->info[i].size > 4) { 174 dev_err(&pdev->dev, 175 "attribute '%s' not 8, 16 or 32 bits wide!\n", 176 hid_time_attrib_name( 177 time_state->info[i].attrib_id)); 178 return -EINVAL; 179 } 180 if (time_state->info[i].units != 181 HID_USAGE_SENSOR_UNITS_NOT_SPECIFIED && 182 /* allow attribute seconds with unit seconds */ 183 !(time_state->info[i].attrib_id == 184 HID_USAGE_SENSOR_TIME_SECOND && 185 time_state->info[i].units == 186 HID_USAGE_SENSOR_UNITS_SECOND)) { 187 dev_err(&pdev->dev, 188 "attribute '%s' hasn't a unit of type 'none'!\n", 189 hid_time_attrib_name( 190 time_state->info[i].attrib_id)); 191 return -EINVAL; 192 } 193 if (time_state->info[i].unit_expo) { 194 dev_err(&pdev->dev, 195 "attribute '%s' hasn't a unit exponent of 1!\n", 196 hid_time_attrib_name( 197 time_state->info[i].attrib_id)); 198 return -EINVAL; 199 } 200 } 201 202 return 0; 203 } 204 205 static int hid_rtc_read_time(struct device *dev, struct rtc_time *tm) 206 { 207 unsigned long flags; 208 struct hid_time_state *time_state = dev_get_drvdata(dev); 209 int ret; 210 211 reinit_completion(&time_state->comp_last_time); 212 /* get a report with all values through requesting one value */ 213 sensor_hub_input_attr_get_raw_value(time_state->common_attributes.hsdev, 214 HID_USAGE_SENSOR_TIME, hid_time_addresses[0], 215 time_state->info[0].report_id, SENSOR_HUB_SYNC, false); 216 /* wait for all values (event) */ 217 ret = wait_for_completion_killable_timeout( 218 &time_state->comp_last_time, HZ*6); 219 if (ret > 0) { 220 /* no error */ 221 spin_lock_irqsave(&time_state->lock_last_time, flags); 222 *tm = time_state->last_time; 223 spin_unlock_irqrestore(&time_state->lock_last_time, flags); 224 return 0; 225 } 226 if (!ret) 227 return -EIO; /* timeouted */ 228 return ret; /* killed (-ERESTARTSYS) */ 229 } 230 231 static const struct rtc_class_ops hid_time_rtc_ops = { 232 .read_time = hid_rtc_read_time, 233 }; 234 235 static int hid_time_probe(struct platform_device *pdev) 236 { 237 int ret = 0; 238 struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev); 239 struct hid_time_state *time_state = devm_kzalloc(&pdev->dev, 240 sizeof(struct hid_time_state), GFP_KERNEL); 241 242 if (time_state == NULL) 243 return -ENOMEM; 244 245 platform_set_drvdata(pdev, time_state); 246 247 spin_lock_init(&time_state->lock_last_time); 248 init_completion(&time_state->comp_last_time); 249 time_state->common_attributes.hsdev = hsdev; 250 time_state->common_attributes.pdev = pdev; 251 252 ret = hid_sensor_parse_common_attributes(hsdev, 253 HID_USAGE_SENSOR_TIME, 254 &time_state->common_attributes); 255 if (ret) { 256 dev_err(&pdev->dev, "failed to setup common attributes!\n"); 257 return ret; 258 } 259 260 ret = hid_time_parse_report(pdev, hsdev, HID_USAGE_SENSOR_TIME, 261 time_state); 262 if (ret) { 263 dev_err(&pdev->dev, "failed to setup attributes!\n"); 264 return ret; 265 } 266 267 time_state->callbacks.send_event = hid_time_proc_event; 268 time_state->callbacks.capture_sample = hid_time_capture_sample; 269 time_state->callbacks.pdev = pdev; 270 ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_TIME, 271 &time_state->callbacks); 272 if (ret < 0) { 273 dev_err(&pdev->dev, "register callback failed!\n"); 274 return ret; 275 } 276 277 ret = sensor_hub_device_open(hsdev); 278 if (ret) { 279 dev_err(&pdev->dev, "failed to open sensor hub device!\n"); 280 goto err_open; 281 } 282 283 /* 284 * Enable HID input processing early in order to be able to read the 285 * clock already in devm_rtc_device_register(). 286 */ 287 hid_device_io_start(hsdev->hdev); 288 289 time_state->rtc = devm_rtc_device_register(&pdev->dev, 290 "hid-sensor-time", &hid_time_rtc_ops, 291 THIS_MODULE); 292 293 if (IS_ERR(time_state->rtc)) { 294 hid_device_io_stop(hsdev->hdev); 295 ret = PTR_ERR(time_state->rtc); 296 time_state->rtc = NULL; 297 dev_err(&pdev->dev, "rtc device register failed!\n"); 298 goto err_rtc; 299 } 300 301 return ret; 302 303 err_rtc: 304 sensor_hub_device_close(hsdev); 305 err_open: 306 sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_TIME); 307 return ret; 308 } 309 310 static int hid_time_remove(struct platform_device *pdev) 311 { 312 struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev); 313 314 sensor_hub_device_close(hsdev); 315 sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_TIME); 316 317 return 0; 318 } 319 320 static const struct platform_device_id hid_time_ids[] = { 321 { 322 /* Format: HID-SENSOR-usage_id_in_hex_lowercase */ 323 .name = "HID-SENSOR-2000a0", 324 }, 325 { /* sentinel */ } 326 }; 327 MODULE_DEVICE_TABLE(platform, hid_time_ids); 328 329 static struct platform_driver hid_time_platform_driver = { 330 .id_table = hid_time_ids, 331 .driver = { 332 .name = KBUILD_MODNAME, 333 }, 334 .probe = hid_time_probe, 335 .remove = hid_time_remove, 336 }; 337 module_platform_driver(hid_time_platform_driver); 338 339 MODULE_DESCRIPTION("HID Sensor Time"); 340 MODULE_AUTHOR("Alexander Holler <holler@ahsoftware.de>"); 341 MODULE_LICENSE("GPL"); 342