[mirror_ubuntu-focal-kernel.git] / drivers / thermal / kirkwood_thermal.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Kirkwood thermal sensor driver
 *
 * Copyright (C) 2012 Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
 */
#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,
			  int *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. According to Marvell internal
	 * documentation the formula for this is:
	 * Celsius = (322-reg)/1.3625
	 */
	reg = (reg >> KIRKWOOD_THERMAL_TEMP_OFFSET) &
		KIRKWOOD_THERMAL_TEMP_MASK;
	*temp = ((3220000000UL - (10000000UL * reg)) / 13625);

	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;

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

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	priv->sensor = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(priv->sensor))
		return PTR_ERR(priv->sensor);

	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);

	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",
		.of_match_table = 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
9c92ab61	1	// SPDX-License-Identifier: GPL-2.0-only
7060aa36 NI	2	/*
	3	* Kirkwood thermal sensor driver
	4	*
	5	* Copyright (C) 2012 Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
7060aa36 NI	6	*/
	7	#include <linux/device.h>
	8	#include <linux/err.h>
	9	#include <linux/io.h>
	10	#include <linux/kernel.h>
	11	#include <linux/of.h>
	12	#include <linux/module.h>
	13	#include <linux/platform_device.h>
	14	#include <linux/thermal.h>
	15
	16	#define KIRKWOOD_THERMAL_VALID_OFFSET 9
	17	#define KIRKWOOD_THERMAL_VALID_MASK 0x1
	18	#define KIRKWOOD_THERMAL_TEMP_OFFSET 10
	19	#define KIRKWOOD_THERMAL_TEMP_MASK 0x1FF
	20
	21	/* Kirkwood Thermal Sensor Dev Structure */
	22	struct kirkwood_thermal_priv {
	23	void __iomem *sensor;
	24	};
	25
	26	static int kirkwood_get_temp(struct thermal_zone_device *thermal,
17e8351a	27	int *temp)
7060aa36 NI	28	{
	29	unsigned long reg;
	30	struct kirkwood_thermal_priv *priv = thermal->devdata;
	31
	32	reg = readl_relaxed(priv->sensor);
	33
	34	/* Valid check */
02519d33 EG	35	if (!((reg >> KIRKWOOD_THERMAL_VALID_OFFSET) &
02519d33 EG	36	KIRKWOOD_THERMAL_VALID_MASK)) {
7060aa36 NI	37	dev_err(&thermal->device,
	38	"Temperature sensor reading not valid\n");
	39	return -EIO;
	40	}
	41
	42	/*
696b6075 EG	43	* Calculate temperature. According to Marvell internal
	44	* documentation the formula for this is:
	45	* Celsius = (322-reg)/1.3625
7060aa36 NI	46	*/
	47	reg = (reg >> KIRKWOOD_THERMAL_TEMP_OFFSET) &
	48	KIRKWOOD_THERMAL_TEMP_MASK;
696b6075	49	temp = ((3220000000UL - (10000000UL reg)) / 13625);
7060aa36 NI	50
	51	return 0;
	52	}
	53
	54	static struct thermal_zone_device_ops ops = {
	55	.get_temp = kirkwood_get_temp,
	56	};
	57
	58	static const struct of_device_id kirkwood_thermal_id_table[] = {
	59	{ .compatible = "marvell,kirkwood-thermal" },
	60	{}
	61	};
	62
	63	static int kirkwood_thermal_probe(struct platform_device *pdev)
	64	{
	65	struct thermal_zone_device *thermal = NULL;
	66	struct kirkwood_thermal_priv *priv;
	67	struct resource *res;
	68
7060aa36 NI	69	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
	70	if (!priv)
	71	return -ENOMEM;
	72
c28f692c	73	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
aa3b5d22 SK	74	priv->sensor = devm_ioremap_resource(&pdev->dev, res);
	75	if (IS_ERR(priv->sensor))
	76	return PTR_ERR(priv->sensor);
7060aa36 NI	77
	78	thermal = thermal_zone_device_register("kirkwood_thermal", 0, 0,
	79	priv, &ops, NULL, 0, 0);
	80	if (IS_ERR(thermal)) {
	81	dev_err(&pdev->dev,
	82	"Failed to register thermal zone device\n");
	83	return PTR_ERR(thermal);
	84	}
	85
	86	platform_set_drvdata(pdev, thermal);
	87
	88	return 0;
	89	}
	90
	91	static int kirkwood_thermal_exit(struct platform_device *pdev)
	92	{
	93	struct thermal_zone_device *kirkwood_thermal =
	94	platform_get_drvdata(pdev);
	95
	96	thermal_zone_device_unregister(kirkwood_thermal);
7060aa36 NI	97
	98	return 0;
	99	}
	100
	101	MODULE_DEVICE_TABLE(of, kirkwood_thermal_id_table);
	102
	103	static struct platform_driver kirkwood_thermal_driver = {
	104	.probe = kirkwood_thermal_probe,
	105	.remove = kirkwood_thermal_exit,
	106	.driver = {
	107	.name = "kirkwood_thermal",
90c3194e	108	.of_match_table = kirkwood_thermal_id_table,
7060aa36 NI	109	},
	110	};
	111
	112	module_platform_driver(kirkwood_thermal_driver);
	113
	114	MODULE_AUTHOR("Nobuhiro Iwamatsu <iwamatsu@nigauri.org>");
	115	MODULE_DESCRIPTION("kirkwood thermal driver");
	116	MODULE_LICENSE("GPL");