[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / hwmon / jz4740-hwmon.c

/*
 * Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
 * JZ4740 SoC HWMON driver
 *
 * This program is free software; you can redistribute it and/or modify it
 * under  the terms of the GNU General  Public License as published by the
 * Free Software Foundation;  either version 2 of the License, or (at your
 * option) any later version.
 *
 * 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.,
 * 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 */

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

#include <linux/completion.h>
#include <linux/mfd/core.h>

#include <linux/hwmon.h>

struct jz4740_hwmon {
	struct resource *mem;
	void __iomem *base;

	int irq;

	const struct mfd_cell *cell;
	struct device *hwmon;

	struct completion read_completion;

	struct mutex lock;
};

static ssize_t jz4740_hwmon_show_name(struct device *dev,
	struct device_attribute *dev_attr, char *buf)
{
	return sprintf(buf, "jz4740\n");
}

static irqreturn_t jz4740_hwmon_irq(int irq, void *data)
{
	struct jz4740_hwmon *hwmon = data;

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

static ssize_t jz4740_hwmon_read_adcin(struct device *dev,
	struct device_attribute *dev_attr, char *buf)
{
	struct jz4740_hwmon *hwmon = dev_get_drvdata(dev);
	struct completion *completion = &hwmon->read_completion;
	long t;
	unsigned long val;
	int ret;

	mutex_lock(&hwmon->lock);

	INIT_COMPLETION(*completion);

	enable_irq(hwmon->irq);
	hwmon->cell->enable(to_platform_device(dev));

	t = wait_for_completion_interruptible_timeout(completion, HZ);

	if (t > 0) {
		val = readw(hwmon->base) & 0xfff;
		val = (val * 3300) >> 12;
		ret = sprintf(buf, "%lu\n", val);
	} else {
		ret = t ? t : -ETIMEDOUT;
	}

	hwmon->cell->disable(to_platform_device(dev));
	disable_irq(hwmon->irq);

	mutex_unlock(&hwmon->lock);

	return ret;
}

static DEVICE_ATTR(name, S_IRUGO, jz4740_hwmon_show_name, NULL);
static DEVICE_ATTR(in0_input, S_IRUGO, jz4740_hwmon_read_adcin, NULL);

static struct attribute *jz4740_hwmon_attributes[] = {
	&dev_attr_name.attr,
	&dev_attr_in0_input.attr,
	NULL
};

static const struct attribute_group jz4740_hwmon_attr_group = {
	.attrs = jz4740_hwmon_attributes,
};

static int jz4740_hwmon_probe(struct platform_device *pdev)
{
	int ret;
	struct jz4740_hwmon *hwmon;

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

	hwmon->cell = mfd_get_cell(pdev);

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

	hwmon->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!hwmon->mem) {
		dev_err(&pdev->dev, "Failed to get platform mmio resource\n");
		return -ENOENT;
	}

	hwmon->mem = devm_request_mem_region(&pdev->dev, hwmon->mem->start,
			resource_size(hwmon->mem), pdev->name);
	if (!hwmon->mem) {
		dev_err(&pdev->dev, "Failed to request mmio memory region\n");
		return -EBUSY;
	}

	hwmon->base = devm_ioremap_nocache(&pdev->dev, hwmon->mem->start,
					   resource_size(hwmon->mem));
	if (!hwmon->base) {
		dev_err(&pdev->dev, "Failed to ioremap mmio memory\n");
		return -EBUSY;
	}

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

	platform_set_drvdata(pdev, hwmon);

	ret = devm_request_irq(&pdev->dev, hwmon->irq, jz4740_hwmon_irq, 0,
			       pdev->name, hwmon);
	if (ret) {
		dev_err(&pdev->dev, "Failed to request irq: %d\n", ret);
		return ret;
	}
	disable_irq(hwmon->irq);

	ret = sysfs_create_group(&pdev->dev.kobj, &jz4740_hwmon_attr_group);
	if (ret) {
		dev_err(&pdev->dev, "Failed to create sysfs group: %d\n", ret);
		return ret;
	}

	hwmon->hwmon = hwmon_device_register(&pdev->dev);
	if (IS_ERR(hwmon->hwmon)) {
		ret = PTR_ERR(hwmon->hwmon);
		goto err_remove_file;
	}

	return 0;

err_remove_file:
	sysfs_remove_group(&pdev->dev.kobj, &jz4740_hwmon_attr_group);
	return ret;
}

static int jz4740_hwmon_remove(struct platform_device *pdev)
{
	struct jz4740_hwmon *hwmon = platform_get_drvdata(pdev);

	hwmon_device_unregister(hwmon->hwmon);
	sysfs_remove_group(&pdev->dev.kobj, &jz4740_hwmon_attr_group);

	return 0;
}

static struct platform_driver jz4740_hwmon_driver = {
	.probe	= jz4740_hwmon_probe,
	.remove = jz4740_hwmon_remove,
	.driver = {
		.name = "jz4740-hwmon",
		.owner = THIS_MODULE,
	},
};

module_platform_driver(jz4740_hwmon_driver);

MODULE_DESCRIPTION("JZ4740 SoC HWMON driver");
MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:jz4740-hwmon");
Commit	Line	Data
7f983ba9 LPC	1	/*
	2	* Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
	3	* JZ4740 SoC HWMON driver
	4	*
	5	* This program is free software; you can redistribute it and/or modify it
	6	* under the terms of the GNU General Public License as published by the
	7	* Free Software Foundation; either version 2 of the License, or (at your
	8	* option) any later version.
	9	*
	10	* You should have received a copy of the GNU General Public License along
	11	* with this program; if not, write to the Free Software Foundation, Inc.,
	12	* 675 Mass Ave, Cambridge, MA 02139, USA.
	13	*
	14	*/
	15
	16	#include <linux/err.h>
	17	#include <linux/interrupt.h>
	18	#include <linux/kernel.h>
	19	#include <linux/module.h>
	20	#include <linux/mutex.h>
	21	#include <linux/platform_device.h>
	22	#include <linux/slab.h>
b25df2bf	23	#include <linux/io.h>
7f983ba9 LPC	24
	25	#include <linux/completion.h>
	26	#include <linux/mfd/core.h>
	27
	28	#include <linux/hwmon.h>
	29
	30	struct jz4740_hwmon {
	31	struct resource *mem;
	32	void __iomem *base;
	33
	34	int irq;
	35
e9300066	36	const struct mfd_cell *cell;
7f983ba9 LPC	37	struct device *hwmon;
	38
	39	struct completion read_completion;
	40
	41	struct mutex lock;
	42	};
	43
	44	static ssize_t jz4740_hwmon_show_name(struct device *dev,
	45	struct device_attribute dev_attr, char buf)
	46	{
	47	return sprintf(buf, "jz4740\n");
	48	}
	49
	50	static irqreturn_t jz4740_hwmon_irq(int irq, void *data)
	51	{
	52	struct jz4740_hwmon *hwmon = data;
	53
	54	complete(&hwmon->read_completion);
	55	return IRQ_HANDLED;
	56	}
	57
	58	static ssize_t jz4740_hwmon_read_adcin(struct device *dev,
	59	struct device_attribute dev_attr, char buf)
	60	{
	61	struct jz4740_hwmon *hwmon = dev_get_drvdata(dev);
	62	struct completion *completion = &hwmon->read_completion;
0b57d760	63	long t;
7f983ba9 LPC	64	unsigned long val;
	65	int ret;
	66
	67	mutex_lock(&hwmon->lock);
	68
	69	INIT_COMPLETION(*completion);
	70
	71	enable_irq(hwmon->irq);
	72	hwmon->cell->enable(to_platform_device(dev));
	73
	74	t = wait_for_completion_interruptible_timeout(completion, HZ);
	75
	76	if (t > 0) {
	77	val = readw(hwmon->base) & 0xfff;
	78	val = (val * 3300) >> 12;
	79	ret = sprintf(buf, "%lu\n", val);
	80	} else {
	81	ret = t ? t : -ETIMEDOUT;
	82	}
	83
	84	hwmon->cell->disable(to_platform_device(dev));
	85	disable_irq(hwmon->irq);
	86
	87	mutex_unlock(&hwmon->lock);
	88
	89	return ret;
	90	}
	91
	92	static DEVICE_ATTR(name, S_IRUGO, jz4740_hwmon_show_name, NULL);
	93	static DEVICE_ATTR(in0_input, S_IRUGO, jz4740_hwmon_read_adcin, NULL);
	94
	95	static struct attribute *jz4740_hwmon_attributes[] = {
	96	&dev_attr_name.attr,
	97	&dev_attr_in0_input.attr,
	98	NULL
	99	};
	100
	101	static const struct attribute_group jz4740_hwmon_attr_group = {
	102	.attrs = jz4740_hwmon_attributes,
	103	};
	104
6c931ae1	105	static int jz4740_hwmon_probe(struct platform_device *pdev)
7f983ba9 LPC	106	{
	107	int ret;
	108	struct jz4740_hwmon *hwmon;
	109
b25df2bf GR	110	hwmon = devm_kzalloc(&pdev->dev, sizeof(*hwmon), GFP_KERNEL);
b25df2bf GR	111	if (!hwmon)
7f983ba9	112	return -ENOMEM;
7f983ba9	113
6a54ac21	114	hwmon->cell = mfd_get_cell(pdev);
7f983ba9 LPC	115
	116	hwmon->irq = platform_get_irq(pdev, 0);
	117	if (hwmon->irq < 0) {
b25df2bf GR	118	dev_err(&pdev->dev, "Failed to get platform irq: %d\n",
	119	hwmon->irq);
	120	return hwmon->irq;
7f983ba9 LPC	121	}
	122
	123	hwmon->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	124	if (!hwmon->mem) {
7f983ba9	125	dev_err(&pdev->dev, "Failed to get platform mmio resource\n");
b25df2bf	126	return -ENOENT;
7f983ba9 LPC	127	}
7f983ba9 LPC	128
b25df2bf	129	hwmon->mem = devm_request_mem_region(&pdev->dev, hwmon->mem->start,
7f983ba9 LPC	130	resource_size(hwmon->mem), pdev->name);
7f983ba9 LPC	131	if (!hwmon->mem) {
7f983ba9	132	dev_err(&pdev->dev, "Failed to request mmio memory region\n");
b25df2bf	133	return -EBUSY;
7f983ba9 LPC	134	}
7f983ba9 LPC	135
b25df2bf GR	136	hwmon->base = devm_ioremap_nocache(&pdev->dev, hwmon->mem->start,
b25df2bf GR	137	resource_size(hwmon->mem));
7f983ba9	138	if (!hwmon->base) {
7f983ba9	139	dev_err(&pdev->dev, "Failed to ioremap mmio memory\n");
b25df2bf	140	return -EBUSY;
7f983ba9 LPC	141	}
	142
	143	init_completion(&hwmon->read_completion);
	144	mutex_init(&hwmon->lock);
	145
	146	platform_set_drvdata(pdev, hwmon);
	147
b25df2bf GR	148	ret = devm_request_irq(&pdev->dev, hwmon->irq, jz4740_hwmon_irq, 0,
b25df2bf GR	149	pdev->name, hwmon);
7f983ba9 LPC	150	if (ret) {
7f983ba9 LPC	151	dev_err(&pdev->dev, "Failed to request irq: %d\n", ret);
b25df2bf	152	return ret;
7f983ba9 LPC	153	}
	154	disable_irq(hwmon->irq);
	155
	156	ret = sysfs_create_group(&pdev->dev.kobj, &jz4740_hwmon_attr_group);
	157	if (ret) {
	158	dev_err(&pdev->dev, "Failed to create sysfs group: %d\n", ret);
b25df2bf	159	return ret;
7f983ba9 LPC	160	}
	161
	162	hwmon->hwmon = hwmon_device_register(&pdev->dev);
	163	if (IS_ERR(hwmon->hwmon)) {
	164	ret = PTR_ERR(hwmon->hwmon);
	165	goto err_remove_file;
	166	}
	167
	168	return 0;
	169
	170	err_remove_file:
	171	sysfs_remove_group(&pdev->dev.kobj, &jz4740_hwmon_attr_group);
7f983ba9 LPC	172	return ret;
	173	}
	174
281dfd0b	175	static int jz4740_hwmon_remove(struct platform_device *pdev)
7f983ba9 LPC	176	{
	177	struct jz4740_hwmon *hwmon = platform_get_drvdata(pdev);
	178
	179	hwmon_device_unregister(hwmon->hwmon);
	180	sysfs_remove_group(&pdev->dev.kobj, &jz4740_hwmon_attr_group);
	181
7f983ba9 LPC	182	return 0;
	183	}
	184
d6c4f2ac	185	static struct platform_driver jz4740_hwmon_driver = {
7f983ba9	186	.probe = jz4740_hwmon_probe,
9e5e9b7a	187	.remove = jz4740_hwmon_remove,
7f983ba9 LPC	188	.driver = {
	189	.name = "jz4740-hwmon",
	190	.owner = THIS_MODULE,
	191	},
	192	};
	193
25a236a5	194	module_platform_driver(jz4740_hwmon_driver);
7f983ba9 LPC	195
	196	MODULE_DESCRIPTION("JZ4740 SoC HWMON driver");
	197	MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
	198	MODULE_LICENSE("GPL");
	199	MODULE_ALIAS("platform:jz4740-hwmon");