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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * HID Sensor Time Driver4 * Copyright (c) 2012, Alexander Holler.5 */6#include <linux/device.h>7#include <linux/platform_device.h>8#include <linux/module.h>9#include <linux/hid-sensor-hub.h>10#include <linux/iio/iio.h>11#include <linux/rtc.h>12 13enum hid_time_channel {14 CHANNEL_SCAN_INDEX_YEAR,15 CHANNEL_SCAN_INDEX_MONTH,16 CHANNEL_SCAN_INDEX_DAY,17 CHANNEL_SCAN_INDEX_HOUR,18 CHANNEL_SCAN_INDEX_MINUTE,19 CHANNEL_SCAN_INDEX_SECOND,20 TIME_RTC_CHANNEL_MAX,21};22 23struct hid_time_state {24 struct hid_sensor_hub_callbacks callbacks;25 struct hid_sensor_common common_attributes;26 struct hid_sensor_hub_attribute_info info[TIME_RTC_CHANNEL_MAX];27 struct rtc_time last_time;28 spinlock_t lock_last_time;29 struct completion comp_last_time;30 struct rtc_time time_buf;31 struct rtc_device *rtc;32};33 34static const u32 hid_time_addresses[TIME_RTC_CHANNEL_MAX] = {35 HID_USAGE_SENSOR_TIME_YEAR,36 HID_USAGE_SENSOR_TIME_MONTH,37 HID_USAGE_SENSOR_TIME_DAY,38 HID_USAGE_SENSOR_TIME_HOUR,39 HID_USAGE_SENSOR_TIME_MINUTE,40 HID_USAGE_SENSOR_TIME_SECOND,41};42 43/* Channel names for verbose error messages */44static const char * const hid_time_channel_names[TIME_RTC_CHANNEL_MAX] = {45 "year", "month", "day", "hour", "minute", "second",46};47 48/* Callback handler to send event after all samples are received and captured */49static int hid_time_proc_event(struct hid_sensor_hub_device *hsdev,50 unsigned usage_id, void *priv)51{52 unsigned long flags;53 struct hid_time_state *time_state = platform_get_drvdata(priv);54 55 spin_lock_irqsave(&time_state->lock_last_time, flags);56 time_state->last_time = time_state->time_buf;57 spin_unlock_irqrestore(&time_state->lock_last_time, flags);58 complete(&time_state->comp_last_time);59 return 0;60}61 62static u32 hid_time_value(size_t raw_len, char *raw_data)63{64 switch (raw_len) {65 case 1:66 return *(u8 *)raw_data;67 case 2:68 return *(u16 *)raw_data;69 case 4:70 return *(u32 *)raw_data;71 default:72 return (u32)(~0U); /* 0xff... or -1 to denote an error */73 }74}75 76static int hid_time_capture_sample(struct hid_sensor_hub_device *hsdev,77 unsigned usage_id, size_t raw_len,78 char *raw_data, void *priv)79{80 struct hid_time_state *time_state = platform_get_drvdata(priv);81 struct rtc_time *time_buf = &time_state->time_buf;82 83 switch (usage_id) {84 case HID_USAGE_SENSOR_TIME_YEAR:85 /*86 * The draft for HID-sensors (HUTRR39) currently doesn't define87 * the range for the year attribute. Therefor we support88 * 8 bit (0-99) and 16 or 32 bits (full) as size for the year.89 */90 if (raw_len == 1) {91 time_buf->tm_year = *(u8 *)raw_data;92 if (time_buf->tm_year < 70)93 /* assume we are in 1970...2069 */94 time_buf->tm_year += 100;95 } else96 time_buf->tm_year =97 (int)hid_time_value(raw_len, raw_data)-1900;98 break;99 case HID_USAGE_SENSOR_TIME_MONTH:100 /* sensors are sending the month as 1-12, we need 0-11 */101 time_buf->tm_mon = (int)hid_time_value(raw_len, raw_data)-1;102 break;103 case HID_USAGE_SENSOR_TIME_DAY:104 time_buf->tm_mday = (int)hid_time_value(raw_len, raw_data);105 break;106 case HID_USAGE_SENSOR_TIME_HOUR:107 time_buf->tm_hour = (int)hid_time_value(raw_len, raw_data);108 break;109 case HID_USAGE_SENSOR_TIME_MINUTE:110 time_buf->tm_min = (int)hid_time_value(raw_len, raw_data);111 break;112 case HID_USAGE_SENSOR_TIME_SECOND:113 time_buf->tm_sec = (int)hid_time_value(raw_len, raw_data);114 break;115 default:116 return -EINVAL;117 }118 return 0;119}120 121/* small helper, haven't found any other way */122static const char *hid_time_attrib_name(u32 attrib_id)123{124 static const char unknown[] = "unknown";125 unsigned i;126 127 for (i = 0; i < TIME_RTC_CHANNEL_MAX; ++i) {128 if (hid_time_addresses[i] == attrib_id)129 return hid_time_channel_names[i];130 }131 return unknown; /* should never happen */132}133 134static int hid_time_parse_report(struct platform_device *pdev,135 struct hid_sensor_hub_device *hsdev,136 unsigned usage_id,137 struct hid_time_state *time_state)138{139 int report_id, i;140 141 for (i = 0; i < TIME_RTC_CHANNEL_MAX; ++i)142 if (sensor_hub_input_get_attribute_info(hsdev,143 HID_INPUT_REPORT, usage_id,144 hid_time_addresses[i],145 &time_state->info[i]) < 0)146 return -EINVAL;147 /* Check the (needed) attributes for sanity */148 report_id = time_state->info[0].report_id;149 if (report_id < 0) {150 dev_err(&pdev->dev, "bad report ID!\n");151 return -EINVAL;152 }153 for (i = 0; i < TIME_RTC_CHANNEL_MAX; ++i) {154 if (time_state->info[i].report_id != report_id) {155 dev_err(&pdev->dev,156 "not all needed attributes inside the same report!\n");157 return -EINVAL;158 }159 if (time_state->info[i].size == 3 ||160 time_state->info[i].size > 4) {161 dev_err(&pdev->dev,162 "attribute '%s' not 8, 16 or 32 bits wide!\n",163 hid_time_attrib_name(164 time_state->info[i].attrib_id));165 return -EINVAL;166 }167 if (time_state->info[i].units !=168 HID_USAGE_SENSOR_UNITS_NOT_SPECIFIED &&169 /* allow attribute seconds with unit seconds */170 !(time_state->info[i].attrib_id ==171 HID_USAGE_SENSOR_TIME_SECOND &&172 time_state->info[i].units ==173 HID_USAGE_SENSOR_UNITS_SECOND)) {174 dev_err(&pdev->dev,175 "attribute '%s' hasn't a unit of type 'none'!\n",176 hid_time_attrib_name(177 time_state->info[i].attrib_id));178 return -EINVAL;179 }180 if (time_state->info[i].unit_expo) {181 dev_err(&pdev->dev,182 "attribute '%s' hasn't a unit exponent of 1!\n",183 hid_time_attrib_name(184 time_state->info[i].attrib_id));185 return -EINVAL;186 }187 }188 189 return 0;190}191 192static int hid_rtc_read_time(struct device *dev, struct rtc_time *tm)193{194 unsigned long flags;195 struct hid_time_state *time_state = dev_get_drvdata(dev);196 int ret;197 198 reinit_completion(&time_state->comp_last_time);199 /* get a report with all values through requesting one value */200 sensor_hub_input_attr_get_raw_value(time_state->common_attributes.hsdev,201 HID_USAGE_SENSOR_TIME, hid_time_addresses[0],202 time_state->info[0].report_id, SENSOR_HUB_SYNC, false);203 /* wait for all values (event) */204 ret = wait_for_completion_killable_timeout(205 &time_state->comp_last_time, HZ*6);206 if (ret > 0) {207 /* no error */208 spin_lock_irqsave(&time_state->lock_last_time, flags);209 *tm = time_state->last_time;210 spin_unlock_irqrestore(&time_state->lock_last_time, flags);211 return 0;212 }213 if (!ret)214 return -EIO; /* timeouted */215 return ret; /* killed (-ERESTARTSYS) */216}217 218static const struct rtc_class_ops hid_time_rtc_ops = {219 .read_time = hid_rtc_read_time,220};221 222static int hid_time_probe(struct platform_device *pdev)223{224 int ret = 0;225 struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);226 struct hid_time_state *time_state = devm_kzalloc(&pdev->dev,227 sizeof(struct hid_time_state), GFP_KERNEL);228 229 if (time_state == NULL)230 return -ENOMEM;231 232 platform_set_drvdata(pdev, time_state);233 234 spin_lock_init(&time_state->lock_last_time);235 init_completion(&time_state->comp_last_time);236 time_state->common_attributes.hsdev = hsdev;237 time_state->common_attributes.pdev = pdev;238 239 ret = hid_sensor_parse_common_attributes(hsdev,240 HID_USAGE_SENSOR_TIME,241 &time_state->common_attributes,242 NULL,243 0);244 if (ret) {245 dev_err(&pdev->dev, "failed to setup common attributes!\n");246 return ret;247 }248 249 ret = hid_time_parse_report(pdev, hsdev, HID_USAGE_SENSOR_TIME,250 time_state);251 if (ret) {252 dev_err(&pdev->dev, "failed to setup attributes!\n");253 return ret;254 }255 256 time_state->callbacks.send_event = hid_time_proc_event;257 time_state->callbacks.capture_sample = hid_time_capture_sample;258 time_state->callbacks.pdev = pdev;259 ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_TIME,260 &time_state->callbacks);261 if (ret < 0) {262 dev_err(&pdev->dev, "register callback failed!\n");263 return ret;264 }265 266 ret = sensor_hub_device_open(hsdev);267 if (ret) {268 dev_err(&pdev->dev, "failed to open sensor hub device!\n");269 goto err_open;270 }271 272 /*273 * Enable HID input processing early in order to be able to read the274 * clock already in devm_rtc_device_register().275 */276 hid_device_io_start(hsdev->hdev);277 278 time_state->rtc = devm_rtc_device_register(&pdev->dev,279 "hid-sensor-time", &hid_time_rtc_ops,280 THIS_MODULE);281 282 if (IS_ERR(time_state->rtc)) {283 hid_device_io_stop(hsdev->hdev);284 ret = PTR_ERR(time_state->rtc);285 time_state->rtc = NULL;286 dev_err(&pdev->dev, "rtc device register failed!\n");287 goto err_rtc;288 }289 290 return ret;291 292err_rtc:293 sensor_hub_device_close(hsdev);294err_open:295 sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_TIME);296 return ret;297}298 299static void hid_time_remove(struct platform_device *pdev)300{301 struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);302 303 sensor_hub_device_close(hsdev);304 sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_TIME);305}306 307static const struct platform_device_id hid_time_ids[] = {308 {309 /* Format: HID-SENSOR-usage_id_in_hex_lowercase */310 .name = "HID-SENSOR-2000a0",311 },312 { /* sentinel */ }313};314MODULE_DEVICE_TABLE(platform, hid_time_ids);315 316static struct platform_driver hid_time_platform_driver = {317 .id_table = hid_time_ids,318 .driver = {319 .name = KBUILD_MODNAME,320 },321 .probe = hid_time_probe,322 .remove_new = hid_time_remove,323};324module_platform_driver(hid_time_platform_driver);325 326MODULE_DESCRIPTION("HID Sensor Time");327MODULE_AUTHOR("Alexander Holler <holler@ahsoftware.de>");328MODULE_LICENSE("GPL");329MODULE_IMPORT_NS(IIO_HID);330