rtc-hid-sensor-time.c 9.6 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37
/*
 * HID Sensor Time Driver
 * Copyright (c) 2012, Alexander Holler.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
 *
 */
#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;
38
	struct hid_sensor_common common_attributes;
39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74
	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;
}

75 76 77 78 79 80 81 82 83 84 85 86 87 88
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 */
	}
}

89 90 91 92 93 94 95 96 97
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:
98 99 100 101 102
		/*
		 * 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.
		 */
103 104 105 106 107 108
		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
109 110
			time_buf->tm_year =
				(int)hid_time_value(raw_len, raw_data)-1900;
111 112
		break;
	case HID_USAGE_SENSOR_TIME_MONTH:
113 114
		/* 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;
115 116
		break;
	case HID_USAGE_SENSOR_TIME_DAY:
117
		time_buf->tm_mday = (int)hid_time_value(raw_len, raw_data);
118 119
		break;
	case HID_USAGE_SENSOR_TIME_HOUR:
120
		time_buf->tm_hour = (int)hid_time_value(raw_len, raw_data);
121 122
		break;
	case HID_USAGE_SENSOR_TIME_MINUTE:
123
		time_buf->tm_min = (int)hid_time_value(raw_len, raw_data);
124 125
		break;
	case HID_USAGE_SENSOR_TIME_SECOND:
126
		time_buf->tm_sec = (int)hid_time_value(raw_len, raw_data);
127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171
		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;
		}
172 173 174 175
		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",
176 177
				hid_time_attrib_name(
					time_state->info[i].attrib_id));
178
			return -EINVAL;
179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211
		}
		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 =
		platform_get_drvdata(to_platform_device(dev));
	int ret;

212
	reinit_completion(&time_state->comp_last_time);
213 214 215
	/* 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],
216
			time_state->info[0].report_id, SENSOR_HUB_SYNC, false);
217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238
	/* 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;
239
	struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
240 241 242 243 244 245 246 247
	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);

248
	spin_lock_init(&time_state->lock_last_time);
249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277
	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);
	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;
	}

278 279 280 281 282 283
	ret = sensor_hub_device_open(hsdev);
	if (ret) {
		dev_err(&pdev->dev, "failed to open sensor hub device!\n");
		goto err_open;
	}

284 285 286 287 288 289
	/*
	 * 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);

290 291 292
	time_state->rtc = devm_rtc_device_register(&pdev->dev,
					"hid-sensor-time", &hid_time_rtc_ops,
					THIS_MODULE);
293

294
	if (IS_ERR(time_state->rtc)) {
295
		hid_device_io_stop(hsdev->hdev);
296
		ret = PTR_ERR(time_state->rtc);
297
		time_state->rtc = NULL;
298
		dev_err(&pdev->dev, "rtc device register failed!\n");
299
		goto err_rtc;
300 301 302
	}

	return ret;
303 304 305 306 307 308

err_rtc:
	sensor_hub_device_close(hsdev);
err_open:
	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_TIME);
	return ret;
309 310 311 312
}

static int hid_time_remove(struct platform_device *pdev)
{
313
	struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
314

315
	sensor_hub_device_close(hsdev);
316 317 318 319 320
	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_TIME);

	return 0;
}

321
static const struct platform_device_id hid_time_ids[] = {
322 323 324 325 326 327 328 329
	{
		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
		.name = "HID-SENSOR-2000a0",
	},
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(platform, hid_time_ids);

330
static struct platform_driver hid_time_platform_driver = {
331
	.id_table = hid_time_ids,
332
	.driver = {
333
		.name	= KBUILD_MODNAME,
334 335 336 337 338 339 340 341 342
	},
	.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");