[linux-2.6-block.git] / drivers / thermal / kirkwood_thermal.c

/*
 * Kirkwood thermal sensor driver
 *
 * Copyright (C) 2012 Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
 *
 * This software is licensed under the terms of the GNU General Public
 * License version 2, as published by the Free Software Foundation, and
 * may be copied, distributed, and modified under those terms.
 *
 * This program is distributed in the hope that 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.
 *
 */
#include <linux/device.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/thermal.h>

#define KIRKWOOD_THERMAL_VALID_OFFSET	9
#define KIRKWOOD_THERMAL_VALID_MASK	0x1
#define KIRKWOOD_THERMAL_TEMP_OFFSET	10
#define KIRKWOOD_THERMAL_TEMP_MASK	0x1FF

/* Kirkwood Thermal Sensor Dev Structure */
struct kirkwood_thermal_priv {
	void __iomem *sensor;
};

static int kirkwood_get_temp(struct thermal_zone_device *thermal,
			  unsigned long *temp)
{
	unsigned long reg;
	struct kirkwood_thermal_priv *priv = thermal->devdata;

	reg = readl_relaxed(priv->sensor);

	/* Valid check */
	if (!(reg >> KIRKWOOD_THERMAL_VALID_OFFSET) &
	    KIRKWOOD_THERMAL_VALID_MASK) {
		dev_err(&thermal->device,
			"Temperature sensor reading not valid\n");
		return -EIO;
	}

	/*
	 * Calculate temperature. See Section 8.10.1 of the 88AP510,
	 * datasheet, which has the same sensor.
	 * Documentation/arm/Marvell/README
	 */
	reg = (reg >> KIRKWOOD_THERMAL_TEMP_OFFSET) &
		KIRKWOOD_THERMAL_TEMP_MASK;
	*temp = ((2281638UL - (7298*reg)) / 10);

	return 0;
}

static struct thermal_zone_device_ops ops = {
	.get_temp = kirkwood_get_temp,
};

static const struct of_device_id kirkwood_thermal_id_table[] = {
	{ .compatible = "marvell,kirkwood-thermal" },
	{}
};

static int kirkwood_thermal_probe(struct platform_device *pdev)
{
	struct thermal_zone_device *thermal = NULL;
	struct kirkwood_thermal_priv *priv;
	struct resource *res;

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

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

	priv->sensor = devm_request_and_ioremap(&pdev->dev, res);
	if (!priv->sensor) {
		dev_err(&pdev->dev, "Failed to request_ioremap memory\n");
		return -EADDRNOTAVAIL;
	}

	thermal = thermal_zone_device_register("kirkwood_thermal", 0, 0,
					       priv, &ops, NULL, 0, 0);
	if (IS_ERR(thermal)) {
		dev_err(&pdev->dev,
			"Failed to register thermal zone device\n");
		return PTR_ERR(thermal);
	}

	platform_set_drvdata(pdev, thermal);

	return 0;
}

static int kirkwood_thermal_exit(struct platform_device *pdev)
{
	struct thermal_zone_device *kirkwood_thermal =
		platform_get_drvdata(pdev);

	thermal_zone_device_unregister(kirkwood_thermal);
	platform_set_drvdata(pdev, NULL);

	return 0;
}

MODULE_DEVICE_TABLE(of, kirkwood_thermal_id_table);

static struct platform_driver kirkwood_thermal_driver = {
	.probe = kirkwood_thermal_probe,
	.remove = kirkwood_thermal_exit,
	.driver = {
		.name = "kirkwood_thermal",
		.owner = THIS_MODULE,
		.of_match_table = of_match_ptr(kirkwood_thermal_id_table),
	},
};

module_platform_driver(kirkwood_thermal_driver);

MODULE_AUTHOR("Nobuhiro Iwamatsu <iwamatsu@nigauri.org>");
MODULE_DESCRIPTION("kirkwood thermal driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
7060aa36 NI	1	/*
	2	* Kirkwood thermal sensor driver
	3	*
	4	* Copyright (C) 2012 Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
	5	*
	6	* This software is licensed under the terms of the GNU General Public
	7	* License version 2, as published by the Free Software Foundation, and
	8	* may be copied, distributed, and modified under those terms.
	9	*
	10	* This program is distributed in the hope that it will be useful,
	11	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	13	* GNU General Public License for more details.
	14	*
	15	*/
	16	#include <linux/device.h>
	17	#include <linux/err.h>
	18	#include <linux/io.h>
	19	#include <linux/kernel.h>
	20	#include <linux/of.h>
	21	#include <linux/module.h>
	22	#include <linux/platform_device.h>
	23	#include <linux/thermal.h>
	24
	25	#define KIRKWOOD_THERMAL_VALID_OFFSET 9
	26	#define KIRKWOOD_THERMAL_VALID_MASK 0x1
	27	#define KIRKWOOD_THERMAL_TEMP_OFFSET 10
	28	#define KIRKWOOD_THERMAL_TEMP_MASK 0x1FF
	29
	30	/* Kirkwood Thermal Sensor Dev Structure */
	31	struct kirkwood_thermal_priv {
	32	void __iomem *sensor;
	33	};
	34
	35	static int kirkwood_get_temp(struct thermal_zone_device *thermal,
	36	unsigned long *temp)
	37	{
	38	unsigned long reg;
	39	struct kirkwood_thermal_priv *priv = thermal->devdata;
	40
	41	reg = readl_relaxed(priv->sensor);
	42
	43	/* Valid check */
	44	if (!(reg >> KIRKWOOD_THERMAL_VALID_OFFSET) &
	45	KIRKWOOD_THERMAL_VALID_MASK) {
	46	dev_err(&thermal->device,
	47	"Temperature sensor reading not valid\n");
	48	return -EIO;
	49	}
	50
	51	/*
	52	* Calculate temperature. See Section 8.10.1 of the 88AP510,
	53	* datasheet, which has the same sensor.
	54	* Documentation/arm/Marvell/README
	55	*/
	56	reg = (reg >> KIRKWOOD_THERMAL_TEMP_OFFSET) &
	57	KIRKWOOD_THERMAL_TEMP_MASK;
	58	temp = ((2281638UL - (7298reg)) / 10);
	59
	60	return 0;
	61	}
	62
	63	static struct thermal_zone_device_ops ops = {
	64	.get_temp = kirkwood_get_temp,
65	};
66
67	static const struct of_device_id kirkwood_thermal_id_table[] = {
68	{ .compatible = "marvell,kirkwood-thermal" },
69	{}
70	};
71
72	static int kirkwood_thermal_probe(struct platform_device *pdev)
73	{
74	struct thermal_zone_device *thermal = NULL;
75	struct kirkwood_thermal_priv *priv;
76	struct resource *res;
77
78	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
79	if (!res) {
80	dev_err(&pdev->dev, "Failed to get platform resource\n");
81	return -ENODEV;
82	}
83
84	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
85	if (!priv)
86	return -ENOMEM;
87
88	priv->sensor = devm_request_and_ioremap(&pdev->dev, res);
89	if (!priv->sensor) {
90	dev_err(&pdev->dev, "Failed to request_ioremap memory\n");
91	return -EADDRNOTAVAIL;
92	}
93
94	thermal = thermal_zone_device_register("kirkwood_thermal", 0, 0,
95	priv, &ops, NULL, 0, 0);
96	if (IS_ERR(thermal)) {
97	dev_err(&pdev->dev,
98	"Failed to register thermal zone device\n");
99	return PTR_ERR(thermal);
100	}
101
102	platform_set_drvdata(pdev, thermal);
103
104	return 0;
105	}
106
107	static int kirkwood_thermal_exit(struct platform_device *pdev)
108	{
109	struct thermal_zone_device *kirkwood_thermal =
110	platform_get_drvdata(pdev);
111
112	thermal_zone_device_unregister(kirkwood_thermal);
113	platform_set_drvdata(pdev, NULL);
114
115	return 0;
116	}
117
118	MODULE_DEVICE_TABLE(of, kirkwood_thermal_id_table);
119
120	static struct platform_driver kirkwood_thermal_driver = {
121	.probe = kirkwood_thermal_probe,
122	.remove = kirkwood_thermal_exit,
123	.driver = {
124	.name = "kirkwood_thermal",
125	.owner = THIS_MODULE,
126	.of_match_table = of_match_ptr(kirkwood_thermal_id_table),
127	},
128	};
129
130	module_platform_driver(kirkwood_thermal_driver);
131
132	MODULE_AUTHOR("Nobuhiro Iwamatsu <iwamatsu@nigauri.org>");
133	MODULE_DESCRIPTION("kirkwood thermal driver");
134	MODULE_LICENSE("GPL");