drivers/rtc/rtc-hid-sensor-time.c - linux - Git at Google

 // 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);
	// 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);