diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/rtc/rtc-hid-sensor-time.c | 331 |
1 files changed, 331 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-hid-sensor-time.c b/drivers/rtc/rtc-hid-sensor-time.c new file mode 100644 index 000000000..16fdefafe --- /dev/null +++ b/drivers/rtc/rtc-hid-sensor-time.c @@ -0,0 +1,331 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * HID Sensor Time Driver + * Copyright (c) 2012, Alexander Holler. + */ +#include <linux/device.h> +#include <linux/platform_device.h> +#include <linux/module.h> +#include <linux/hid-sensor-hub.h> +#include <linux/iio/iio.h> +#include <linux/rtc.h> + +enum hid_time_channel { + CHANNEL_SCAN_INDEX_YEAR, + CHANNEL_SCAN_INDEX_MONTH, + CHANNEL_SCAN_INDEX_DAY, + CHANNEL_SCAN_INDEX_HOUR, + CHANNEL_SCAN_INDEX_MINUTE, + CHANNEL_SCAN_INDEX_SECOND, + TIME_RTC_CHANNEL_MAX, +}; + +struct hid_time_state { + struct hid_sensor_hub_callbacks callbacks; + struct hid_sensor_common common_attributes; + struct hid_sensor_hub_attribute_info info[TIME_RTC_CHANNEL_MAX]; + struct rtc_time last_time; + spinlock_t lock_last_time; + struct completion comp_last_time; + struct rtc_time time_buf; + struct rtc_device *rtc; +}; + +static const u32 hid_time_addresses[TIME_RTC_CHANNEL_MAX] = { + HID_USAGE_SENSOR_TIME_YEAR, + HID_USAGE_SENSOR_TIME_MONTH, + HID_USAGE_SENSOR_TIME_DAY, + HID_USAGE_SENSOR_TIME_HOUR, + HID_USAGE_SENSOR_TIME_MINUTE, + HID_USAGE_SENSOR_TIME_SECOND, +}; + +/* Channel names for verbose error messages */ +static const char * const hid_time_channel_names[TIME_RTC_CHANNEL_MAX] = { + "year", "month", "day", "hour", "minute", "second", +}; + +/* Callback handler to send event after all samples are received and captured */ +static int hid_time_proc_event(struct hid_sensor_hub_device *hsdev, + unsigned usage_id, void *priv) +{ + unsigned long flags; + struct hid_time_state *time_state = platform_get_drvdata(priv); + + spin_lock_irqsave(&time_state->lock_last_time, flags); + time_state->last_time = time_state->time_buf; + spin_unlock_irqrestore(&time_state->lock_last_time, flags); + complete(&time_state->comp_last_time); + return 0; +} + +static u32 hid_time_value(size_t raw_len, char *raw_data) +{ + switch (raw_len) { + case 1: + return *(u8 *)raw_data; + case 2: + return *(u16 *)raw_data; + case 4: + return *(u32 *)raw_data; + default: + return (u32)(~0U); /* 0xff... or -1 to denote an error */ + } +} + +static int hid_time_capture_sample(struct hid_sensor_hub_device *hsdev, + unsigned usage_id, size_t raw_len, + char *raw_data, void *priv) +{ + struct hid_time_state *time_state = platform_get_drvdata(priv); + struct rtc_time *time_buf = &time_state->time_buf; + + switch (usage_id) { + case HID_USAGE_SENSOR_TIME_YEAR: + /* + * The draft for HID-sensors (HUTRR39) currently doesn't define + * the range for the year attribute. Therefor we support + * 8 bit (0-99) and 16 or 32 bits (full) as size for the year. + */ + if (raw_len == 1) { + time_buf->tm_year = *(u8 *)raw_data; + if (time_buf->tm_year < 70) + /* assume we are in 1970...2069 */ + time_buf->tm_year += 100; + } else + time_buf->tm_year = + (int)hid_time_value(raw_len, raw_data)-1900; + break; + case HID_USAGE_SENSOR_TIME_MONTH: + /* sensors are sending the month as 1-12, we need 0-11 */ + time_buf->tm_mon = (int)hid_time_value(raw_len, raw_data)-1; + break; + case HID_USAGE_SENSOR_TIME_DAY: + time_buf->tm_mday = (int)hid_time_value(raw_len, raw_data); + break; + case HID_USAGE_SENSOR_TIME_HOUR: + time_buf->tm_hour = (int)hid_time_value(raw_len, raw_data); + break; + case HID_USAGE_SENSOR_TIME_MINUTE: + time_buf->tm_min = (int)hid_time_value(raw_len, raw_data); + break; + case HID_USAGE_SENSOR_TIME_SECOND: + time_buf->tm_sec = (int)hid_time_value(raw_len, raw_data); + break; + default: + return -EINVAL; + } + return 0; +} + +/* small helper, haven't found any other way */ +static const char *hid_time_attrib_name(u32 attrib_id) +{ + static const char unknown[] = "unknown"; + unsigned i; + + for (i = 0; i < TIME_RTC_CHANNEL_MAX; ++i) { + if (hid_time_addresses[i] == attrib_id) + return hid_time_channel_names[i]; + } + return unknown; /* should never happen */ +} + +static int hid_time_parse_report(struct platform_device *pdev, + struct hid_sensor_hub_device *hsdev, + unsigned usage_id, + struct hid_time_state *time_state) +{ + int report_id, i; + + for (i = 0; i < TIME_RTC_CHANNEL_MAX; ++i) + if (sensor_hub_input_get_attribute_info(hsdev, + HID_INPUT_REPORT, usage_id, + hid_time_addresses[i], + &time_state->info[i]) < 0) + return -EINVAL; + /* Check the (needed) attributes for sanity */ + report_id = time_state->info[0].report_id; + if (report_id < 0) { + dev_err(&pdev->dev, "bad report ID!\n"); + return -EINVAL; + } + for (i = 0; i < TIME_RTC_CHANNEL_MAX; ++i) { + if (time_state->info[i].report_id != report_id) { + dev_err(&pdev->dev, + "not all needed attributes inside the same report!\n"); + return -EINVAL; + } + if (time_state->info[i].size == 3 || + time_state->info[i].size > 4) { + dev_err(&pdev->dev, + "attribute '%s' not 8, 16 or 32 bits wide!\n", + hid_time_attrib_name( + time_state->info[i].attrib_id)); + return -EINVAL; + } + if (time_state->info[i].units != + HID_USAGE_SENSOR_UNITS_NOT_SPECIFIED && + /* allow attribute seconds with unit seconds */ + !(time_state->info[i].attrib_id == + HID_USAGE_SENSOR_TIME_SECOND && + time_state->info[i].units == + HID_USAGE_SENSOR_UNITS_SECOND)) { + dev_err(&pdev->dev, + "attribute '%s' hasn't a unit of type 'none'!\n", + hid_time_attrib_name( + time_state->info[i].attrib_id)); + return -EINVAL; + } + if (time_state->info[i].unit_expo) { + dev_err(&pdev->dev, + "attribute '%s' hasn't a unit exponent of 1!\n", + hid_time_attrib_name( + time_state->info[i].attrib_id)); + return -EINVAL; + } + } + + return 0; +} + +static int hid_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + unsigned long flags; + struct hid_time_state *time_state = dev_get_drvdata(dev); + int ret; + + reinit_completion(&time_state->comp_last_time); + /* get a report with all values through requesting one value */ + sensor_hub_input_attr_get_raw_value(time_state->common_attributes.hsdev, + HID_USAGE_SENSOR_TIME, hid_time_addresses[0], + time_state->info[0].report_id, SENSOR_HUB_SYNC, false); + /* wait for all values (event) */ + ret = wait_for_completion_killable_timeout( + &time_state->comp_last_time, HZ*6); + if (ret > 0) { + /* no error */ + spin_lock_irqsave(&time_state->lock_last_time, flags); + *tm = time_state->last_time; + spin_unlock_irqrestore(&time_state->lock_last_time, flags); + return 0; + } + if (!ret) + return -EIO; /* timeouted */ + return ret; /* killed (-ERESTARTSYS) */ +} + +static const struct rtc_class_ops hid_time_rtc_ops = { + .read_time = hid_rtc_read_time, +}; + +static int hid_time_probe(struct platform_device *pdev) +{ + int ret = 0; + struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev); + struct hid_time_state *time_state = devm_kzalloc(&pdev->dev, + sizeof(struct hid_time_state), GFP_KERNEL); + + if (time_state == NULL) + return -ENOMEM; + + platform_set_drvdata(pdev, time_state); + + spin_lock_init(&time_state->lock_last_time); + init_completion(&time_state->comp_last_time); + time_state->common_attributes.hsdev = hsdev; + time_state->common_attributes.pdev = pdev; + + ret = hid_sensor_parse_common_attributes(hsdev, + HID_USAGE_SENSOR_TIME, + &time_state->common_attributes, + NULL, + 0); + if (ret) { + dev_err(&pdev->dev, "failed to setup common attributes!\n"); + return ret; + } + + ret = hid_time_parse_report(pdev, hsdev, HID_USAGE_SENSOR_TIME, + time_state); + if (ret) { + dev_err(&pdev->dev, "failed to setup attributes!\n"); + return ret; + } + + time_state->callbacks.send_event = hid_time_proc_event; + time_state->callbacks.capture_sample = hid_time_capture_sample; + time_state->callbacks.pdev = pdev; + ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_TIME, + &time_state->callbacks); + if (ret < 0) { + dev_err(&pdev->dev, "register callback failed!\n"); + return ret; + } + + ret = sensor_hub_device_open(hsdev); + if (ret) { + dev_err(&pdev->dev, "failed to open sensor hub device!\n"); + goto err_open; + } + + /* + * Enable HID input processing early in order to be able to read the + * clock already in devm_rtc_device_register(). + */ + hid_device_io_start(hsdev->hdev); + + time_state->rtc = devm_rtc_device_register(&pdev->dev, + "hid-sensor-time", &hid_time_rtc_ops, + THIS_MODULE); + + if (IS_ERR(time_state->rtc)) { + hid_device_io_stop(hsdev->hdev); + ret = PTR_ERR(time_state->rtc); + time_state->rtc = NULL; + dev_err(&pdev->dev, "rtc device register failed!\n"); + goto err_rtc; + } + + return ret; + +err_rtc: + sensor_hub_device_close(hsdev); +err_open: + sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_TIME); + return ret; +} + +static int hid_time_remove(struct platform_device *pdev) +{ + struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev); + + sensor_hub_device_close(hsdev); + sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_TIME); + + return 0; +} + +static const struct platform_device_id hid_time_ids[] = { + { + /* Format: HID-SENSOR-usage_id_in_hex_lowercase */ + .name = "HID-SENSOR-2000a0", + }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(platform, hid_time_ids); + +static struct platform_driver hid_time_platform_driver = { + .id_table = hid_time_ids, + .driver = { + .name = KBUILD_MODNAME, + }, + .probe = hid_time_probe, + .remove = hid_time_remove, +}; +module_platform_driver(hid_time_platform_driver); + +MODULE_DESCRIPTION("HID Sensor Time"); +MODULE_AUTHOR("Alexander Holler <holler@ahsoftware.de>"); +MODULE_LICENSE("GPL"); +MODULE_IMPORT_NS(IIO_HID); |