jz4740-battery.c 10.2 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
/*
 * Battery measurement code for Ingenic JZ SOC.
 *
 * Copyright (C) 2009 Jiejing Zhang <kzjeef@gmail.com>
 * Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
 *
 * based on tosa_battery.c
 *
 * Copyright (C) 2008 Marek Vasut <marek.vasut@gmail.com>
*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */

#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/io.h>

#include <linux/delay.h>
#include <linux/err.h>
#include <linux/gpio.h>
#include <linux/mfd/core.h>
#include <linux/power_supply.h>

#include <linux/power/jz4740-battery.h>
#include <linux/jz4740-adc.h>

struct jz_battery {
	struct jz_battery_platform_data *pdata;
	struct platform_device *pdev;

	void __iomem *base;

	int irq;
	int charge_irq;

	const struct mfd_cell *cell;

	int status;
	long voltage;

	struct completion read_completion;

	struct power_supply battery;
	struct delayed_work work;

	struct mutex lock;
};

static inline struct jz_battery *psy_to_jz_battery(struct power_supply *psy)
{
	return container_of(psy, struct jz_battery, battery);
}

static irqreturn_t jz_battery_irq_handler(int irq, void *devid)
{
	struct jz_battery *battery = devid;

	complete(&battery->read_completion);
	return IRQ_HANDLED;
}

static long jz_battery_read_voltage(struct jz_battery *battery)
{
	long t;
	unsigned long val;
	long voltage;

	mutex_lock(&battery->lock);

	reinit_completion(&battery->read_completion);

	enable_irq(battery->irq);
	battery->cell->enable(battery->pdev);

	t = wait_for_completion_interruptible_timeout(&battery->read_completion,
		HZ);

	if (t > 0) {
		val = readw(battery->base) & 0xfff;

		if (battery->pdata->info.voltage_max_design <= 2500000)
			val = (val * 78125UL) >> 7UL;
		else
			val = ((val * 924375UL) >> 9UL) + 33000;
		voltage = (long)val;
	} else {
		voltage = t ? t : -ETIMEDOUT;
	}

	battery->cell->disable(battery->pdev);
	disable_irq(battery->irq);

	mutex_unlock(&battery->lock);

	return voltage;
}

static int jz_battery_get_capacity(struct power_supply *psy)
{
	struct jz_battery *jz_battery = psy_to_jz_battery(psy);
	struct power_supply_info *info = &jz_battery->pdata->info;
	long voltage;
	int ret;
	int voltage_span;

	voltage = jz_battery_read_voltage(jz_battery);

	if (voltage < 0)
		return voltage;

	voltage_span = info->voltage_max_design - info->voltage_min_design;
	ret = ((voltage - info->voltage_min_design) * 100) / voltage_span;

	if (ret > 100)
		ret = 100;
	else if (ret < 0)
		ret = 0;

	return ret;
}

static int jz_battery_get_property(struct power_supply *psy,
	enum power_supply_property psp, union power_supply_propval *val)
{
	struct jz_battery *jz_battery = psy_to_jz_battery(psy);
	struct power_supply_info *info = &jz_battery->pdata->info;
	long voltage;

	switch (psp) {
	case POWER_SUPPLY_PROP_STATUS:
		val->intval = jz_battery->status;
		break;
	case POWER_SUPPLY_PROP_TECHNOLOGY:
		val->intval = jz_battery->pdata->info.technology;
		break;
	case POWER_SUPPLY_PROP_HEALTH:
		voltage = jz_battery_read_voltage(jz_battery);
		if (voltage < info->voltage_min_design)
			val->intval = POWER_SUPPLY_HEALTH_DEAD;
		else
			val->intval = POWER_SUPPLY_HEALTH_GOOD;
		break;
	case POWER_SUPPLY_PROP_CAPACITY:
		val->intval = jz_battery_get_capacity(psy);
		break;
	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
		val->intval = jz_battery_read_voltage(jz_battery);
		if (val->intval < 0)
			return val->intval;
		break;
	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
		val->intval = info->voltage_max_design;
		break;
	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
		val->intval = info->voltage_min_design;
		break;
	case POWER_SUPPLY_PROP_PRESENT:
		val->intval = 1;
		break;
	default:
		return -EINVAL;
	}
	return 0;
}

static void jz_battery_external_power_changed(struct power_supply *psy)
{
	struct jz_battery *jz_battery = psy_to_jz_battery(psy);

	mod_delayed_work(system_wq, &jz_battery->work, 0);
}

static irqreturn_t jz_battery_charge_irq(int irq, void *data)
{
	struct jz_battery *jz_battery = data;

	mod_delayed_work(system_wq, &jz_battery->work, 0);

	return IRQ_HANDLED;
}

static void jz_battery_update(struct jz_battery *jz_battery)
{
	int status;
	long voltage;
	bool has_changed = false;
	int is_charging;

	if (gpio_is_valid(jz_battery->pdata->gpio_charge)) {
		is_charging = gpio_get_value(jz_battery->pdata->gpio_charge);
		is_charging ^= jz_battery->pdata->gpio_charge_active_low;
		if (is_charging)
			status = POWER_SUPPLY_STATUS_CHARGING;
		else
			status = POWER_SUPPLY_STATUS_NOT_CHARGING;

		if (status != jz_battery->status) {
			jz_battery->status = status;
			has_changed = true;
		}
	}

	voltage = jz_battery_read_voltage(jz_battery);
	if (abs(voltage - jz_battery->voltage) < 50000) {
		jz_battery->voltage = voltage;
		has_changed = true;
	}

	if (has_changed)
		power_supply_changed(&jz_battery->battery);
}

static enum power_supply_property jz_battery_properties[] = {
	POWER_SUPPLY_PROP_STATUS,
	POWER_SUPPLY_PROP_TECHNOLOGY,
	POWER_SUPPLY_PROP_HEALTH,
	POWER_SUPPLY_PROP_CAPACITY,
	POWER_SUPPLY_PROP_VOLTAGE_NOW,
	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
	POWER_SUPPLY_PROP_PRESENT,
};

static void jz_battery_work(struct work_struct *work)
{
	/* Too small interval will increase system workload */
	const int interval = HZ * 30;
	struct jz_battery *jz_battery = container_of(work, struct jz_battery,
					    work.work);

	jz_battery_update(jz_battery);
	schedule_delayed_work(&jz_battery->work, interval);
}

static int jz_battery_probe(struct platform_device *pdev)
{
	int ret = 0;
	struct jz_battery_platform_data *pdata = pdev->dev.parent->platform_data;
	struct jz_battery *jz_battery;
	struct power_supply *battery;
	struct resource *mem;

	if (!pdata) {
		dev_err(&pdev->dev, "No platform_data supplied\n");
		return -ENXIO;
	}

	jz_battery = devm_kzalloc(&pdev->dev, sizeof(*jz_battery), GFP_KERNEL);
	if (!jz_battery) {
		dev_err(&pdev->dev, "Failed to allocate driver structure\n");
		return -ENOMEM;
	}

	jz_battery->cell = mfd_get_cell(pdev);

	jz_battery->irq = platform_get_irq(pdev, 0);
	if (jz_battery->irq < 0) {
		dev_err(&pdev->dev, "Failed to get platform irq: %d\n", ret);
		return jz_battery->irq;
	}

	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	jz_battery->base = devm_ioremap_resource(&pdev->dev, mem);
	if (IS_ERR(jz_battery->base))
		return PTR_ERR(jz_battery->base);

	battery = &jz_battery->battery;
	battery->name = pdata->info.name;
	battery->type = POWER_SUPPLY_TYPE_BATTERY;
	battery->properties	= jz_battery_properties;
	battery->num_properties	= ARRAY_SIZE(jz_battery_properties);
	battery->get_property = jz_battery_get_property;
	battery->external_power_changed = jz_battery_external_power_changed;
	battery->use_for_apm = 1;

	jz_battery->pdata = pdata;
	jz_battery->pdev = pdev;

	init_completion(&jz_battery->read_completion);
	mutex_init(&jz_battery->lock);

	INIT_DELAYED_WORK(&jz_battery->work, jz_battery_work);

	ret = request_irq(jz_battery->irq, jz_battery_irq_handler, 0, pdev->name,
			jz_battery);
	if (ret) {
		dev_err(&pdev->dev, "Failed to request irq %d\n", ret);
		return ret;
	}
	disable_irq(jz_battery->irq);

	if (gpio_is_valid(pdata->gpio_charge)) {
		ret = gpio_request(pdata->gpio_charge, dev_name(&pdev->dev));
		if (ret) {
			dev_err(&pdev->dev, "charger state gpio request failed.\n");
			goto err_free_irq;
		}
		ret = gpio_direction_input(pdata->gpio_charge);
		if (ret) {
			dev_err(&pdev->dev, "charger state gpio set direction failed.\n");
			goto err_free_gpio;
		}

		jz_battery->charge_irq = gpio_to_irq(pdata->gpio_charge);

		if (jz_battery->charge_irq >= 0) {
			ret = request_irq(jz_battery->charge_irq,
				    jz_battery_charge_irq,
				    IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
				    dev_name(&pdev->dev), jz_battery);
			if (ret) {
				dev_err(&pdev->dev, "Failed to request charge irq: %d\n", ret);
				goto err_free_gpio;
			}
		}
	} else {
		jz_battery->charge_irq = -1;
	}

	if (jz_battery->pdata->info.voltage_max_design <= 2500000)
		jz4740_adc_set_config(pdev->dev.parent, JZ_ADC_CONFIG_BAT_MB,
			JZ_ADC_CONFIG_BAT_MB);
	else
		jz4740_adc_set_config(pdev->dev.parent, JZ_ADC_CONFIG_BAT_MB, 0);

	ret = power_supply_register(&pdev->dev, &jz_battery->battery);
	if (ret) {
		dev_err(&pdev->dev, "power supply battery register failed.\n");
		goto err_free_charge_irq;
	}

	platform_set_drvdata(pdev, jz_battery);
	schedule_delayed_work(&jz_battery->work, 0);

	return 0;

err_free_charge_irq:
	if (jz_battery->charge_irq >= 0)
		free_irq(jz_battery->charge_irq, jz_battery);
err_free_gpio:
	if (gpio_is_valid(pdata->gpio_charge))
		gpio_free(jz_battery->pdata->gpio_charge);
err_free_irq:
	free_irq(jz_battery->irq, jz_battery);
	return ret;
}

static int jz_battery_remove(struct platform_device *pdev)
{
	struct jz_battery *jz_battery = platform_get_drvdata(pdev);

	cancel_delayed_work_sync(&jz_battery->work);

	if (gpio_is_valid(jz_battery->pdata->gpio_charge)) {
		if (jz_battery->charge_irq >= 0)
			free_irq(jz_battery->charge_irq, jz_battery);
		gpio_free(jz_battery->pdata->gpio_charge);
	}

	power_supply_unregister(&jz_battery->battery);

	free_irq(jz_battery->irq, jz_battery);

	return 0;
}

#ifdef CONFIG_PM
static int jz_battery_suspend(struct device *dev)
{
	struct jz_battery *jz_battery = dev_get_drvdata(dev);

	cancel_delayed_work_sync(&jz_battery->work);
	jz_battery->status = POWER_SUPPLY_STATUS_UNKNOWN;

	return 0;
}

static int jz_battery_resume(struct device *dev)
{
	struct jz_battery *jz_battery = dev_get_drvdata(dev);

	schedule_delayed_work(&jz_battery->work, 0);

	return 0;
}

static const struct dev_pm_ops jz_battery_pm_ops = {
	.suspend	= jz_battery_suspend,
	.resume		= jz_battery_resume,
};

#define JZ_BATTERY_PM_OPS (&jz_battery_pm_ops)
#else
#define JZ_BATTERY_PM_OPS NULL
#endif

static struct platform_driver jz_battery_driver = {
	.probe		= jz_battery_probe,
	.remove		= jz_battery_remove,
	.driver = {
		.name = "jz4740-battery",
		.owner = THIS_MODULE,
		.pm = JZ_BATTERY_PM_OPS,
	},
};

module_platform_driver(jz_battery_driver);

MODULE_ALIAS("platform:jz4740-battery");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
MODULE_DESCRIPTION("JZ4740 SoC battery driver");