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 /* Format: HID-SENSOR-usage_id_in_hex */ 27 /* Usage ID from spec for Time: 0x2000A0 */ 28 #define DRIVER_NAME "HID-SENSOR-2000a0" /* must be lowercase */ 29 30 enum hid_time_channel { 31 CHANNEL_SCAN_INDEX_YEAR, 32 CHANNEL_SCAN_INDEX_MONTH, 33 CHANNEL_SCAN_INDEX_DAY, 34 CHANNEL_SCAN_INDEX_HOUR, 35 CHANNEL_SCAN_INDEX_MINUTE, 36 CHANNEL_SCAN_INDEX_SECOND, 37 TIME_RTC_CHANNEL_MAX, 38 }; 39 40 struct hid_time_state { 41 struct hid_sensor_hub_callbacks callbacks; 42 struct hid_sensor_common common_attributes; 43 struct hid_sensor_hub_attribute_info info[TIME_RTC_CHANNEL_MAX]; 44 struct rtc_time last_time; 45 spinlock_t lock_last_time; 46 struct completion comp_last_time; 47 struct rtc_time time_buf; 48 struct rtc_device *rtc; 49 }; 50 51 static const u32 hid_time_addresses[TIME_RTC_CHANNEL_MAX] = { 52 HID_USAGE_SENSOR_TIME_YEAR, 53 HID_USAGE_SENSOR_TIME_MONTH, 54 HID_USAGE_SENSOR_TIME_DAY, 55 HID_USAGE_SENSOR_TIME_HOUR, 56 HID_USAGE_SENSOR_TIME_MINUTE, 57 HID_USAGE_SENSOR_TIME_SECOND, 58 }; 59 60 /* Channel names for verbose error messages */ 61 static const char * const hid_time_channel_names[TIME_RTC_CHANNEL_MAX] = { 62 "year", "month", "day", "hour", "minute", "second", 63 }; 64 65 /* Callback handler to send event after all samples are received and captured */ 66 static int hid_time_proc_event(struct hid_sensor_hub_device *hsdev, 67 unsigned usage_id, void *priv) 68 { 69 unsigned long flags; 70 struct hid_time_state *time_state = platform_get_drvdata(priv); 71 72 spin_lock_irqsave(&time_state->lock_last_time, flags); 73 time_state->last_time = time_state->time_buf; 74 spin_unlock_irqrestore(&time_state->lock_last_time, flags); 75 complete(&time_state->comp_last_time); 76 return 0; 77 } 78 79 static u32 hid_time_value(size_t raw_len, char *raw_data) 80 { 81 switch (raw_len) { 82 case 1: 83 return *(u8 *)raw_data; 84 case 2: 85 return *(u16 *)raw_data; 86 case 4: 87 return *(u32 *)raw_data; 88 default: 89 return (u32)(~0U); /* 0xff... or -1 to denote an error */ 90 } 91 } 92 93 static int hid_time_capture_sample(struct hid_sensor_hub_device *hsdev, 94 unsigned usage_id, size_t raw_len, 95 char *raw_data, void *priv) 96 { 97 struct hid_time_state *time_state = platform_get_drvdata(priv); 98 struct rtc_time *time_buf = &time_state->time_buf; 99 100 switch (usage_id) { 101 case HID_USAGE_SENSOR_TIME_YEAR: 102 /* 103 * The draft for HID-sensors (HUTRR39) currently doesn't define 104 * the range for the year attribute. Therefor we support 105 * 8 bit (0-99) and 16 or 32 bits (full) as size for the year. 106 */ 107 if (raw_len == 1) { 108 time_buf->tm_year = *(u8 *)raw_data; 109 if (time_buf->tm_year < 70) 110 /* assume we are in 1970...2069 */ 111 time_buf->tm_year += 100; 112 } else 113 time_buf->tm_year = 114 (int)hid_time_value(raw_len, raw_data)-1900; 115 break; 116 case HID_USAGE_SENSOR_TIME_MONTH: 117 /* sensors are sending the month as 1-12, we need 0-11 */ 118 time_buf->tm_mon = (int)hid_time_value(raw_len, raw_data)-1; 119 break; 120 case HID_USAGE_SENSOR_TIME_DAY: 121 time_buf->tm_mday = (int)hid_time_value(raw_len, raw_data); 122 break; 123 case HID_USAGE_SENSOR_TIME_HOUR: 124 time_buf->tm_hour = (int)hid_time_value(raw_len, raw_data); 125 break; 126 case HID_USAGE_SENSOR_TIME_MINUTE: 127 time_buf->tm_min = (int)hid_time_value(raw_len, raw_data); 128 break; 129 case HID_USAGE_SENSOR_TIME_SECOND: 130 time_buf->tm_sec = (int)hid_time_value(raw_len, raw_data); 131 break; 132 default: 133 return -EINVAL; 134 } 135 return 0; 136 } 137 138 /* small helper, haven't found any other way */ 139 static const char *hid_time_attrib_name(u32 attrib_id) 140 { 141 static const char unknown[] = "unknown"; 142 unsigned i; 143 144 for (i = 0; i < TIME_RTC_CHANNEL_MAX; ++i) { 145 if (hid_time_addresses[i] == attrib_id) 146 return hid_time_channel_names[i]; 147 } 148 return unknown; /* should never happen */ 149 } 150 151 static int hid_time_parse_report(struct platform_device *pdev, 152 struct hid_sensor_hub_device *hsdev, 153 unsigned usage_id, 154 struct hid_time_state *time_state) 155 { 156 int report_id, i; 157 158 for (i = 0; i < TIME_RTC_CHANNEL_MAX; ++i) 159 if (sensor_hub_input_get_attribute_info(hsdev, 160 HID_INPUT_REPORT, usage_id, 161 hid_time_addresses[i], 162 &time_state->info[i]) < 0) 163 return -EINVAL; 164 /* Check the (needed) attributes for sanity */ 165 report_id = time_state->info[0].report_id; 166 if (report_id < 0) { 167 dev_err(&pdev->dev, "bad report ID!\n"); 168 return -EINVAL; 169 } 170 for (i = 0; i < TIME_RTC_CHANNEL_MAX; ++i) { 171 if (time_state->info[i].report_id != report_id) { 172 dev_err(&pdev->dev, 173 "not all needed attributes inside the same report!\n"); 174 return -EINVAL; 175 } 176 if (time_state->info[i].size == 3 || 177 time_state->info[i].size > 4) { 178 dev_err(&pdev->dev, 179 "attribute '%s' not 8, 16 or 32 bits wide!\n", 180 hid_time_attrib_name( 181 time_state->info[i].attrib_id)); 182 return -EINVAL; 183 } 184 if (time_state->info[i].units != 185 HID_USAGE_SENSOR_UNITS_NOT_SPECIFIED && 186 /* allow attribute seconds with unit seconds */ 187 !(time_state->info[i].attrib_id == 188 HID_USAGE_SENSOR_TIME_SECOND && 189 time_state->info[i].units == 190 HID_USAGE_SENSOR_UNITS_SECOND)) { 191 dev_err(&pdev->dev, 192 "attribute '%s' hasn't a unit of type 'none'!\n", 193 hid_time_attrib_name( 194 time_state->info[i].attrib_id)); 195 return -EINVAL; 196 } 197 if (time_state->info[i].unit_expo) { 198 dev_err(&pdev->dev, 199 "attribute '%s' hasn't a unit exponent of 1!\n", 200 hid_time_attrib_name( 201 time_state->info[i].attrib_id)); 202 return -EINVAL; 203 } 204 } 205 206 return 0; 207 } 208 209 static int hid_rtc_read_time(struct device *dev, struct rtc_time *tm) 210 { 211 unsigned long flags; 212 struct hid_time_state *time_state = 213 platform_get_drvdata(to_platform_device(dev)); 214 int ret; 215 216 INIT_COMPLETION(time_state->comp_last_time); 217 /* get a report with all values through requesting one value */ 218 sensor_hub_input_attr_get_raw_value(time_state->common_attributes.hsdev, 219 HID_USAGE_SENSOR_TIME, hid_time_addresses[0], 220 time_state->info[0].report_id); 221 /* wait for all values (event) */ 222 ret = wait_for_completion_killable_timeout( 223 &time_state->comp_last_time, HZ*6); 224 if (ret > 0) { 225 /* no error */ 226 spin_lock_irqsave(&time_state->lock_last_time, flags); 227 *tm = time_state->last_time; 228 spin_unlock_irqrestore(&time_state->lock_last_time, flags); 229 return 0; 230 } 231 if (!ret) 232 return -EIO; /* timeouted */ 233 return ret; /* killed (-ERESTARTSYS) */ 234 } 235 236 static const struct rtc_class_ops hid_time_rtc_ops = { 237 .read_time = hid_rtc_read_time, 238 }; 239 240 static int hid_time_probe(struct platform_device *pdev) 241 { 242 int ret = 0; 243 struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data; 244 struct hid_time_state *time_state = devm_kzalloc(&pdev->dev, 245 sizeof(struct hid_time_state), GFP_KERNEL); 246 247 if (time_state == NULL) 248 return -ENOMEM; 249 250 platform_set_drvdata(pdev, time_state); 251 252 spin_lock_init(&time_state->lock_last_time); 253 init_completion(&time_state->comp_last_time); 254 time_state->common_attributes.hsdev = hsdev; 255 time_state->common_attributes.pdev = pdev; 256 257 ret = hid_sensor_parse_common_attributes(hsdev, 258 HID_USAGE_SENSOR_TIME, 259 &time_state->common_attributes); 260 if (ret) { 261 dev_err(&pdev->dev, "failed to setup common attributes!\n"); 262 return ret; 263 } 264 265 ret = hid_time_parse_report(pdev, hsdev, HID_USAGE_SENSOR_TIME, 266 time_state); 267 if (ret) { 268 dev_err(&pdev->dev, "failed to setup attributes!\n"); 269 return ret; 270 } 271 272 time_state->callbacks.send_event = hid_time_proc_event; 273 time_state->callbacks.capture_sample = hid_time_capture_sample; 274 time_state->callbacks.pdev = pdev; 275 ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_TIME, 276 &time_state->callbacks); 277 if (ret < 0) { 278 dev_err(&pdev->dev, "register callback failed!\n"); 279 return ret; 280 } 281 282 time_state->rtc = devm_rtc_device_register(&pdev->dev, 283 "hid-sensor-time", &hid_time_rtc_ops, 284 THIS_MODULE); 285 286 if (IS_ERR(time_state->rtc)) { 287 dev_err(&pdev->dev, "rtc device register failed!\n"); 288 return PTR_ERR(time_state->rtc); 289 } 290 291 return ret; 292 } 293 294 static int hid_time_remove(struct platform_device *pdev) 295 { 296 struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data; 297 298 sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_TIME); 299 300 return 0; 301 } 302 303 static struct platform_driver hid_time_platform_driver = { 304 .driver = { 305 .name = DRIVER_NAME, 306 .owner = THIS_MODULE, 307 }, 308 .probe = hid_time_probe, 309 .remove = hid_time_remove, 310 }; 311 module_platform_driver(hid_time_platform_driver); 312 313 MODULE_DESCRIPTION("HID Sensor Time"); 314 MODULE_AUTHOR("Alexander Holler <holler@ahsoftware.de>"); 315 MODULE_LICENSE("GPL"); 316