abx500.c 14.1 KB
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 38 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 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491
/*
 * Copyright (C) ST-Ericsson 2010 - 2013
 * Author: Martin Persson <martin.persson@stericsson.com>
 *         Hongbo Zhang <hongbo.zhang@linaro.org>
 * License Terms: GNU General Public License v2
 *
 * ABX500 does not provide auto ADC, so to monitor the required temperatures,
 * a periodic work is used. It is more important to not wake up the CPU than
 * to perform this job, hence the use of a deferred delay.
 *
 * A deferred delay for thermal monitor is considered safe because:
 * If the chip gets too hot during a sleep state it's most likely due to
 * external factors, such as the surrounding temperature. I.e. no SW decisions
 * will make any difference.
 */

#include <linux/err.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/interrupt.h>
#include <linux/jiffies.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pm.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/workqueue.h>
#include "abx500.h"

#define DEFAULT_MONITOR_DELAY	HZ
#define DEFAULT_MAX_TEMP	130

static inline void schedule_monitor(struct abx500_temp *data)
{
	data->work_active = true;
	schedule_delayed_work(&data->work, DEFAULT_MONITOR_DELAY);
}

static void threshold_updated(struct abx500_temp *data)
{
	int i;
	for (i = 0; i < data->monitored_sensors; i++)
		if (data->max[i] != 0 || data->min[i] != 0) {
			schedule_monitor(data);
			return;
		}

	dev_dbg(&data->pdev->dev, "No active thresholds.\n");
	cancel_delayed_work_sync(&data->work);
	data->work_active = false;
}

static void gpadc_monitor(struct work_struct *work)
{
	int temp, i, ret;
	char alarm_node[30];
	bool updated_min_alarm, updated_max_alarm;
	struct abx500_temp *data;

	data = container_of(work, struct abx500_temp, work.work);
	mutex_lock(&data->lock);

	for (i = 0; i < data->monitored_sensors; i++) {
		/* Thresholds are considered inactive if set to 0 */
		if (data->max[i] == 0 && data->min[i] == 0)
			continue;

		if (data->max[i] < data->min[i])
			continue;

		ret = data->ops.read_sensor(data, data->gpadc_addr[i], &temp);
		if (ret < 0) {
			dev_err(&data->pdev->dev, "GPADC read failed\n");
			continue;
		}

		updated_min_alarm = false;
		updated_max_alarm = false;

		if (data->min[i] != 0) {
			if (temp < data->min[i]) {
				if (data->min_alarm[i] == false) {
					data->min_alarm[i] = true;
					updated_min_alarm = true;
				}
			} else {
				if (data->min_alarm[i] == true) {
					data->min_alarm[i] = false;
					updated_min_alarm = true;
				}
			}
		}
		if (data->max[i] != 0) {
			if (temp > data->max[i]) {
				if (data->max_alarm[i] == false) {
					data->max_alarm[i] = true;
					updated_max_alarm = true;
				}
			} else if (temp < data->max[i] - data->max_hyst[i]) {
				if (data->max_alarm[i] == true) {
					data->max_alarm[i] = false;
					updated_max_alarm = true;
				}
			}
		}

		if (updated_min_alarm) {
			ret = sprintf(alarm_node, "temp%d_min_alarm", i + 1);
			sysfs_notify(&data->pdev->dev.kobj, NULL, alarm_node);
		}
		if (updated_max_alarm) {
			ret = sprintf(alarm_node, "temp%d_max_alarm", i + 1);
			sysfs_notify(&data->pdev->dev.kobj, NULL, alarm_node);
		}
	}

	schedule_monitor(data);
	mutex_unlock(&data->lock);
}

/* HWMON sysfs interfaces */
static ssize_t show_name(struct device *dev, struct device_attribute *devattr,
			 char *buf)
{
	struct abx500_temp *data = dev_get_drvdata(dev);
	/* Show chip name */
	return data->ops.show_name(dev, devattr, buf);
}

static ssize_t show_label(struct device *dev,
			  struct device_attribute *devattr, char *buf)
{
	struct abx500_temp *data = dev_get_drvdata(dev);
	/* Show each sensor label */
	return data->ops.show_label(dev, devattr, buf);
}

static ssize_t show_input(struct device *dev,
			  struct device_attribute *devattr, char *buf)
{
	int ret, temp;
	struct abx500_temp *data = dev_get_drvdata(dev);
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
	u8 gpadc_addr = data->gpadc_addr[attr->index];

	ret = data->ops.read_sensor(data, gpadc_addr, &temp);
	if (ret < 0)
		return ret;

	return sprintf(buf, "%d\n", temp);
}

/* Set functions (RW nodes) */
static ssize_t set_min(struct device *dev, struct device_attribute *devattr,
		       const char *buf, size_t count)
{
	unsigned long val;
	struct abx500_temp *data = dev_get_drvdata(dev);
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
	int res = kstrtol(buf, 10, &val);
	if (res < 0)
		return res;

	val = clamp_val(val, 0, DEFAULT_MAX_TEMP);

	mutex_lock(&data->lock);
	data->min[attr->index] = val;
	threshold_updated(data);
	mutex_unlock(&data->lock);

	return count;
}

static ssize_t set_max(struct device *dev, struct device_attribute *devattr,
		       const char *buf, size_t count)
{
	unsigned long val;
	struct abx500_temp *data = dev_get_drvdata(dev);
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
	int res = kstrtol(buf, 10, &val);
	if (res < 0)
		return res;

	val = clamp_val(val, 0, DEFAULT_MAX_TEMP);

	mutex_lock(&data->lock);
	data->max[attr->index] = val;
	threshold_updated(data);
	mutex_unlock(&data->lock);

	return count;
}

static ssize_t set_max_hyst(struct device *dev,
			    struct device_attribute *devattr,
			    const char *buf, size_t count)
{
	unsigned long val;
	struct abx500_temp *data = dev_get_drvdata(dev);
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
	int res = kstrtoul(buf, 10, &val);
	if (res < 0)
		return res;

	val = clamp_val(val, 0, DEFAULT_MAX_TEMP);

	mutex_lock(&data->lock);
	data->max_hyst[attr->index] = val;
	threshold_updated(data);
	mutex_unlock(&data->lock);

	return count;
}

/* Show functions (RO nodes) */
static ssize_t show_min(struct device *dev,
			struct device_attribute *devattr, char *buf)
{
	struct abx500_temp *data = dev_get_drvdata(dev);
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);

	return sprintf(buf, "%ld\n", data->min[attr->index]);
}

static ssize_t show_max(struct device *dev,
			struct device_attribute *devattr, char *buf)
{
	struct abx500_temp *data = dev_get_drvdata(dev);
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);

	return sprintf(buf, "%ld\n", data->max[attr->index]);
}

static ssize_t show_max_hyst(struct device *dev,
			     struct device_attribute *devattr, char *buf)
{
	struct abx500_temp *data = dev_get_drvdata(dev);
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);

	return sprintf(buf, "%ld\n", data->max_hyst[attr->index]);
}

static ssize_t show_min_alarm(struct device *dev,
			      struct device_attribute *devattr, char *buf)
{
	struct abx500_temp *data = dev_get_drvdata(dev);
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);

	return sprintf(buf, "%d\n", data->min_alarm[attr->index]);
}

static ssize_t show_max_alarm(struct device *dev,
			      struct device_attribute *devattr, char *buf)
{
	struct abx500_temp *data = dev_get_drvdata(dev);
	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);

	return sprintf(buf, "%d\n", data->max_alarm[attr->index]);
}

static umode_t abx500_attrs_visible(struct kobject *kobj,
				   struct attribute *attr, int n)
{
	struct device *dev = container_of(kobj, struct device, kobj);
	struct abx500_temp *data = dev_get_drvdata(dev);

	if (data->ops.is_visible)
		return data->ops.is_visible(attr, n);

	return attr->mode;
}

/* Chip name, required by hwmon */
static SENSOR_DEVICE_ATTR(name, S_IRUGO, show_name, NULL, 0);

/* GPADC - SENSOR1 */
static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_label, NULL, 0);
static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_input, NULL, 0);
static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO, show_min, set_min, 0);
static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_max, set_max, 0);
static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
			  show_max_hyst, set_max_hyst, 0);
static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_min_alarm, NULL, 0);
static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_max_alarm, NULL, 0);

/* GPADC - SENSOR2 */
static SENSOR_DEVICE_ATTR(temp2_label, S_IRUGO, show_label, NULL, 1);
static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_input, NULL, 1);
static SENSOR_DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_min, set_min, 1);
static SENSOR_DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_max, set_max, 1);
static SENSOR_DEVICE_ATTR(temp2_max_hyst, S_IWUSR | S_IRUGO,
			  show_max_hyst, set_max_hyst, 1);
static SENSOR_DEVICE_ATTR(temp2_min_alarm, S_IRUGO, show_min_alarm, NULL, 1);
static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_max_alarm, NULL, 1);

/* GPADC - SENSOR3 */
static SENSOR_DEVICE_ATTR(temp3_label, S_IRUGO, show_label, NULL, 2);
static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_input, NULL, 2);
static SENSOR_DEVICE_ATTR(temp3_min, S_IWUSR | S_IRUGO, show_min, set_min, 2);
static SENSOR_DEVICE_ATTR(temp3_max, S_IWUSR | S_IRUGO, show_max, set_max, 2);
static SENSOR_DEVICE_ATTR(temp3_max_hyst, S_IWUSR | S_IRUGO,
			  show_max_hyst, set_max_hyst, 2);
static SENSOR_DEVICE_ATTR(temp3_min_alarm, S_IRUGO, show_min_alarm, NULL, 2);
static SENSOR_DEVICE_ATTR(temp3_max_alarm, S_IRUGO, show_max_alarm, NULL, 2);

/* GPADC - SENSOR4 */
static SENSOR_DEVICE_ATTR(temp4_label, S_IRUGO, show_label, NULL, 3);
static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_input, NULL, 3);
static SENSOR_DEVICE_ATTR(temp4_min, S_IWUSR | S_IRUGO, show_min, set_min, 3);
static SENSOR_DEVICE_ATTR(temp4_max, S_IWUSR | S_IRUGO, show_max, set_max, 3);
static SENSOR_DEVICE_ATTR(temp4_max_hyst, S_IWUSR | S_IRUGO,
			  show_max_hyst, set_max_hyst, 3);
static SENSOR_DEVICE_ATTR(temp4_min_alarm, S_IRUGO, show_min_alarm, NULL, 3);
static SENSOR_DEVICE_ATTR(temp4_max_alarm, S_IRUGO, show_max_alarm, NULL, 3);

static struct attribute *abx500_temp_attributes[] = {
	&sensor_dev_attr_name.dev_attr.attr,

	&sensor_dev_attr_temp1_label.dev_attr.attr,
	&sensor_dev_attr_temp1_input.dev_attr.attr,
	&sensor_dev_attr_temp1_min.dev_attr.attr,
	&sensor_dev_attr_temp1_max.dev_attr.attr,
	&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
	&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
	&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,

	&sensor_dev_attr_temp2_label.dev_attr.attr,
	&sensor_dev_attr_temp2_input.dev_attr.attr,
	&sensor_dev_attr_temp2_min.dev_attr.attr,
	&sensor_dev_attr_temp2_max.dev_attr.attr,
	&sensor_dev_attr_temp2_max_hyst.dev_attr.attr,
	&sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
	&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,

	&sensor_dev_attr_temp3_label.dev_attr.attr,
	&sensor_dev_attr_temp3_input.dev_attr.attr,
	&sensor_dev_attr_temp3_min.dev_attr.attr,
	&sensor_dev_attr_temp3_max.dev_attr.attr,
	&sensor_dev_attr_temp3_max_hyst.dev_attr.attr,
	&sensor_dev_attr_temp3_min_alarm.dev_attr.attr,
	&sensor_dev_attr_temp3_max_alarm.dev_attr.attr,

	&sensor_dev_attr_temp4_label.dev_attr.attr,
	&sensor_dev_attr_temp4_input.dev_attr.attr,
	&sensor_dev_attr_temp4_min.dev_attr.attr,
	&sensor_dev_attr_temp4_max.dev_attr.attr,
	&sensor_dev_attr_temp4_max_hyst.dev_attr.attr,
	&sensor_dev_attr_temp4_min_alarm.dev_attr.attr,
	&sensor_dev_attr_temp4_max_alarm.dev_attr.attr,
	NULL
};

static const struct attribute_group abx500_temp_group = {
	.attrs = abx500_temp_attributes,
	.is_visible = abx500_attrs_visible,
};

static irqreturn_t abx500_temp_irq_handler(int irq, void *irq_data)
{
	struct platform_device *pdev = irq_data;
	struct abx500_temp *data = platform_get_drvdata(pdev);

	data->ops.irq_handler(irq, data);
	return IRQ_HANDLED;
}

static int setup_irqs(struct platform_device *pdev)
{
	int ret;
	int irq = platform_get_irq_byname(pdev, "ABX500_TEMP_WARM");

	if (irq < 0) {
		dev_err(&pdev->dev, "Get irq by name failed\n");
		return irq;
	}

	ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
		abx500_temp_irq_handler, IRQF_NO_SUSPEND, "abx500-temp", pdev);
	if (ret < 0)
		dev_err(&pdev->dev, "Request threaded irq failed (%d)\n", ret);

	return ret;
}

static int abx500_temp_probe(struct platform_device *pdev)
{
	struct abx500_temp *data;
	int err;

	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	data->pdev = pdev;
	mutex_init(&data->lock);

	/* Chip specific initialization */
	err = abx500_hwmon_init(data);
	if (err	< 0 || !data->ops.read_sensor || !data->ops.show_name ||
			!data->ops.show_label)
		return err;

	INIT_DEFERRABLE_WORK(&data->work, gpadc_monitor);

	platform_set_drvdata(pdev, data);

	err = sysfs_create_group(&pdev->dev.kobj, &abx500_temp_group);
	if (err < 0) {
		dev_err(&pdev->dev, "Create sysfs group failed (%d)\n", err);
		return err;
	}

	data->hwmon_dev = hwmon_device_register(&pdev->dev);
	if (IS_ERR(data->hwmon_dev)) {
		err = PTR_ERR(data->hwmon_dev);
		dev_err(&pdev->dev, "Class registration failed (%d)\n", err);
		goto exit_sysfs_group;
	}

	if (data->ops.irq_handler) {
		err = setup_irqs(pdev);
		if (err < 0)
			goto exit_hwmon_reg;
	}
	return 0;

exit_hwmon_reg:
	hwmon_device_unregister(data->hwmon_dev);
exit_sysfs_group:
	sysfs_remove_group(&pdev->dev.kobj, &abx500_temp_group);
	return err;
}

static int abx500_temp_remove(struct platform_device *pdev)
{
	struct abx500_temp *data = platform_get_drvdata(pdev);

	cancel_delayed_work_sync(&data->work);
	hwmon_device_unregister(data->hwmon_dev);
	sysfs_remove_group(&pdev->dev.kobj, &abx500_temp_group);

	return 0;
}

static int abx500_temp_suspend(struct platform_device *pdev,
			       pm_message_t state)
{
	struct abx500_temp *data = platform_get_drvdata(pdev);

	if (data->work_active)
		cancel_delayed_work_sync(&data->work);

	return 0;
}

static int abx500_temp_resume(struct platform_device *pdev)
{
	struct abx500_temp *data = platform_get_drvdata(pdev);

	if (data->work_active)
		schedule_monitor(data);

	return 0;
}

#ifdef CONFIG_OF
static const struct of_device_id abx500_temp_match[] = {
	{ .compatible = "stericsson,abx500-temp" },
	{},
};
#endif

static struct platform_driver abx500_temp_driver = {
	.driver = {
		.owner = THIS_MODULE,
		.name = "abx500-temp",
		.of_match_table = of_match_ptr(abx500_temp_match),
	},
	.suspend = abx500_temp_suspend,
	.resume = abx500_temp_resume,
	.probe = abx500_temp_probe,
	.remove = abx500_temp_remove,
};

module_platform_driver(abx500_temp_driver);

MODULE_AUTHOR("Martin Persson <martin.persson@stericsson.com>");
MODULE_DESCRIPTION("ABX500 temperature driver");
MODULE_LICENSE("GPL");