[mirror_ubuntu-artful-kernel.git] / drivers / thermal / spear_thermal.c

/*
 * SPEAr thermal driver.
 *
 * Copyright (C) 2011-2012 ST Microelectronics
 * Author: Vincenzo Frascino <vincenzo.frascino@st.com>
 *
 * 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/clk.h>
#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 MD_FACTOR	1000

/* SPEAr Thermal Sensor Dev Structure */
struct spear_thermal_dev {
	/* pointer to base address of the thermal sensor */
	void __iomem *thermal_base;
	/* clk structure */
	struct clk *clk;
	/* pointer to thermal flags */
	unsigned int flags;
};

static inline int thermal_get_temp(struct thermal_zone_device *thermal,
				unsigned long *temp)
{
	struct spear_thermal_dev *stdev = thermal->devdata;

	/*
	 * Data are ready to be read after 628 usec from POWERDOWN signal
	 * (PDN) = 1
	 */
	*temp = (readl_relaxed(stdev->thermal_base) & 0x7F) * MD_FACTOR;
	return 0;
}

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

#ifdef CONFIG_PM
static int spear_thermal_suspend(struct device *dev)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct thermal_zone_device *spear_thermal = platform_get_drvdata(pdev);
	struct spear_thermal_dev *stdev = spear_thermal->devdata;
	unsigned int actual_mask = 0;

	/* Disable SPEAr Thermal Sensor */
	actual_mask = readl_relaxed(stdev->thermal_base);
	writel_relaxed(actual_mask & ~stdev->flags, stdev->thermal_base);

	clk_disable(stdev->clk);
	dev_info(dev, "Suspended.\n");

	return 0;
}

static int spear_thermal_resume(struct device *dev)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct thermal_zone_device *spear_thermal = platform_get_drvdata(pdev);
	struct spear_thermal_dev *stdev = spear_thermal->devdata;
	unsigned int actual_mask = 0;
	int ret = 0;

	ret = clk_enable(stdev->clk);
	if (ret) {
		dev_err(&pdev->dev, "Can't enable clock\n");
		return ret;
	}

	/* Enable SPEAr Thermal Sensor */
	actual_mask = readl_relaxed(stdev->thermal_base);
	writel_relaxed(actual_mask | stdev->flags, stdev->thermal_base);

	dev_info(dev, "Resumed.\n");

	return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(spear_thermal_pm_ops, spear_thermal_suspend,
		spear_thermal_resume);

static int spear_thermal_probe(struct platform_device *pdev)
{
	struct thermal_zone_device *spear_thermal = NULL;
	struct spear_thermal_dev *stdev;
	struct device_node *np = pdev->dev.of_node;
	struct resource *stres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	int ret = 0, val;

	if (!np || !of_property_read_u32(np, "st,thermal-flags", &val)) {
		dev_err(&pdev->dev, "Failed: DT Pdata not passed\n");
		return -EINVAL;
	}

	if (!stres) {
		dev_err(&pdev->dev, "memory resource missing\n");
		return -ENODEV;
	}

	stdev = devm_kzalloc(&pdev->dev, sizeof(*stdev), GFP_KERNEL);
	if (!stdev) {
		dev_err(&pdev->dev, "kzalloc fail\n");
		return -ENOMEM;
	}

	/* Enable thermal sensor */
	stdev->thermal_base = devm_ioremap(&pdev->dev, stres->start,
			resource_size(stres));
	if (!stdev->thermal_base) {
		dev_err(&pdev->dev, "ioremap failed\n");
		return -ENOMEM;
	}

	stdev->clk = devm_clk_get(&pdev->dev, NULL);
	if (IS_ERR(stdev->clk)) {
		dev_err(&pdev->dev, "Can't get clock\n");
		return PTR_ERR(stdev->clk);
	}

	ret = clk_enable(stdev->clk);
	if (ret) {
		dev_err(&pdev->dev, "Can't enable clock\n");
		return ret;
	}

	stdev->flags = val;
	writel_relaxed(stdev->flags, stdev->thermal_base);

	spear_thermal = thermal_zone_device_register("spear_thermal", 0, 0,
				stdev, &ops, NULL, 0, 0);
	if (IS_ERR(spear_thermal)) {
		dev_err(&pdev->dev, "thermal zone device is NULL\n");
		ret = PTR_ERR(spear_thermal);
		goto disable_clk;
	}

	platform_set_drvdata(pdev, spear_thermal);

	dev_info(&spear_thermal->device, "Thermal Sensor Loaded at: 0x%p.\n",
			stdev->thermal_base);

	return 0;

disable_clk:
	clk_disable(stdev->clk);

	return ret;
}

static int spear_thermal_exit(struct platform_device *pdev)
{
	unsigned int actual_mask = 0;
	struct thermal_zone_device *spear_thermal = platform_get_drvdata(pdev);
	struct spear_thermal_dev *stdev = spear_thermal->devdata;

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

	/* Disable SPEAr Thermal Sensor */
	actual_mask = readl_relaxed(stdev->thermal_base);
	writel_relaxed(actual_mask & ~stdev->flags, stdev->thermal_base);

	clk_disable(stdev->clk);

	return 0;
}

static const struct of_device_id spear_thermal_id_table[] = {
	{ .compatible = "st,thermal-spear1340" },
	{}
};
MODULE_DEVICE_TABLE(of, spear_thermal_id_table);

static struct platform_driver spear_thermal_driver = {
	.probe = spear_thermal_probe,
	.remove = spear_thermal_exit,
	.driver = {
		.name = "spear_thermal",
		.owner = THIS_MODULE,
		.pm = &spear_thermal_pm_ops,
		.of_match_table = spear_thermal_id_table,
	},
};

module_platform_driver(spear_thermal_driver);

MODULE_AUTHOR("Vincenzo Frascino <vincenzo.frascino@st.com>");
MODULE_DESCRIPTION("SPEAr thermal driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
6a92c366 VF	1	/*
	2	* SPEAr thermal driver.
	3	*
	4	* Copyright (C) 2011-2012 ST Microelectronics
	5	* Author: Vincenzo Frascino <vincenzo.frascino@st.com>
	6	*
	7	* This software is licensed under the terms of the GNU General Public
	8	* License version 2, as published by the Free Software Foundation, and
	9	* may be copied, distributed, and modified under those terms.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	*/
	17
	18	#include <linux/clk.h>
	19	#include <linux/device.h>
	20	#include <linux/err.h>
	21	#include <linux/io.h>
	22	#include <linux/kernel.h>
b9c7aff4	23	#include <linux/of.h>
6a92c366 VF	24	#include <linux/module.h>
6a92c366 VF	25	#include <linux/platform_device.h>
6a92c366 VF	26	#include <linux/thermal.h>
	27
	28	#define MD_FACTOR 1000
	29
	30	/* SPEAr Thermal Sensor Dev Structure */
	31	struct spear_thermal_dev {
	32	/* pointer to base address of the thermal sensor */
	33	void __iomem *thermal_base;
	34	/* clk structure */
	35	struct clk *clk;
	36	/* pointer to thermal flags */
	37	unsigned int flags;
	38	};
	39
	40	static inline int thermal_get_temp(struct thermal_zone_device *thermal,
	41	unsigned long *temp)
	42	{
	43	struct spear_thermal_dev *stdev = thermal->devdata;
	44
	45	/*
	46	* Data are ready to be read after 628 usec from POWERDOWN signal
	47	* (PDN) = 1
	48	*/
de716e32	49	temp = (readl_relaxed(stdev->thermal_base) & 0x7F) MD_FACTOR;
6a92c366 VF	50	return 0;
	51	}
	52
	53	static struct thermal_zone_device_ops ops = {
	54	.get_temp = thermal_get_temp,
	55	};
	56
	57	#ifdef CONFIG_PM
	58	static int spear_thermal_suspend(struct device *dev)
	59	{
	60	struct platform_device *pdev = to_platform_device(dev);
	61	struct thermal_zone_device *spear_thermal = platform_get_drvdata(pdev);
	62	struct spear_thermal_dev *stdev = spear_thermal->devdata;
	63	unsigned int actual_mask = 0;
	64
	65	/* Disable SPEAr Thermal Sensor */
de716e32 VK	66	actual_mask = readl_relaxed(stdev->thermal_base);
de716e32 VK	67	writel_relaxed(actual_mask & ~stdev->flags, stdev->thermal_base);
6a92c366 VF	68
	69	clk_disable(stdev->clk);
	70	dev_info(dev, "Suspended.\n");
	71
	72	return 0;
	73	}
	74
	75	static int spear_thermal_resume(struct device *dev)
	76	{
	77	struct platform_device *pdev = to_platform_device(dev);
	78	struct thermal_zone_device *spear_thermal = platform_get_drvdata(pdev);
	79	struct spear_thermal_dev *stdev = spear_thermal->devdata;
	80	unsigned int actual_mask = 0;
	81	int ret = 0;
	82
	83	ret = clk_enable(stdev->clk);
	84	if (ret) {
	85	dev_err(&pdev->dev, "Can't enable clock\n");
	86	return ret;
	87	}
	88
	89	/* Enable SPEAr Thermal Sensor */
de716e32 VK	90	actual_mask = readl_relaxed(stdev->thermal_base);
de716e32 VK	91	writel_relaxed(actual_mask \| stdev->flags, stdev->thermal_base);
6a92c366 VF	92
	93	dev_info(dev, "Resumed.\n");
	94
	95	return 0;
	96	}
	97	#endif
	98
	99	static SIMPLE_DEV_PM_OPS(spear_thermal_pm_ops, spear_thermal_suspend,
	100	spear_thermal_resume);
	101
	102	static int spear_thermal_probe(struct platform_device *pdev)
	103	{
	104	struct thermal_zone_device *spear_thermal = NULL;
	105	struct spear_thermal_dev *stdev;
b9c7aff4	106	struct device_node *np = pdev->dev.of_node;
6a92c366	107	struct resource *stres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
b9c7aff4 VK	108	int ret = 0, val;
	109
	110	if (!np \|\| !of_property_read_u32(np, "st,thermal-flags", &val)) {
	111	dev_err(&pdev->dev, "Failed: DT Pdata not passed\n");
	112	return -EINVAL;
	113	}
6a92c366 VF	114
	115	if (!stres) {
	116	dev_err(&pdev->dev, "memory resource missing\n");
	117	return -ENODEV;
	118	}
	119
6a92c366 VF	120	stdev = devm_kzalloc(&pdev->dev, sizeof(*stdev), GFP_KERNEL);
	121	if (!stdev) {
	122	dev_err(&pdev->dev, "kzalloc fail\n");
	123	return -ENOMEM;
	124	}
	125
	126	/* Enable thermal sensor */
	127	stdev->thermal_base = devm_ioremap(&pdev->dev, stres->start,
	128	resource_size(stres));
	129	if (!stdev->thermal_base) {
	130	dev_err(&pdev->dev, "ioremap failed\n");
	131	return -ENOMEM;
	132	}
	133
03b79bda	134	stdev->clk = devm_clk_get(&pdev->dev, NULL);
6a92c366 VF	135	if (IS_ERR(stdev->clk)) {
	136	dev_err(&pdev->dev, "Can't get clock\n");
	137	return PTR_ERR(stdev->clk);
	138	}
	139
	140	ret = clk_enable(stdev->clk);
	141	if (ret) {
	142	dev_err(&pdev->dev, "Can't enable clock\n");
03b79bda	143	return ret;
6a92c366 VF	144	}
6a92c366 VF	145
b9c7aff4	146	stdev->flags = val;
de716e32	147	writel_relaxed(stdev->flags, stdev->thermal_base);
6a92c366	148
c56f5c03	149	spear_thermal = thermal_zone_device_register("spear_thermal", 0, 0,
50125a9b	150	stdev, &ops, NULL, 0, 0);
03ee62f0	151	if (IS_ERR(spear_thermal)) {
6a92c366	152	dev_err(&pdev->dev, "thermal zone device is NULL\n");
03ee62f0	153	ret = PTR_ERR(spear_thermal);
6a92c366 VF	154	goto disable_clk;
	155	}
	156
	157	platform_set_drvdata(pdev, spear_thermal);
	158
	159	dev_info(&spear_thermal->device, "Thermal Sensor Loaded at: 0x%p.\n",
	160	stdev->thermal_base);
	161
	162	return 0;
	163
	164	disable_clk:
	165	clk_disable(stdev->clk);
6a92c366 VF	166
	167	return ret;
	168	}
	169
	170	static int spear_thermal_exit(struct platform_device *pdev)
	171	{
	172	unsigned int actual_mask = 0;
	173	struct thermal_zone_device *spear_thermal = platform_get_drvdata(pdev);
	174	struct spear_thermal_dev *stdev = spear_thermal->devdata;
	175
	176	thermal_zone_device_unregister(spear_thermal);
	177	platform_set_drvdata(pdev, NULL);
	178
	179	/* Disable SPEAr Thermal Sensor */
de716e32 VK	180	actual_mask = readl_relaxed(stdev->thermal_base);
de716e32 VK	181	writel_relaxed(actual_mask & ~stdev->flags, stdev->thermal_base);
6a92c366 VF	182
6a92c366 VF	183	clk_disable(stdev->clk);
6a92c366 VF	184
	185	return 0;
	186	}
	187
b9c7aff4 VK	188	static const struct of_device_id spear_thermal_id_table[] = {
	189	{ .compatible = "st,thermal-spear1340" },
	190	{}
	191	};
	192	MODULE_DEVICE_TABLE(of, spear_thermal_id_table);
	193
6a92c366 VF	194	static struct platform_driver spear_thermal_driver = {
	195	.probe = spear_thermal_probe,
	196	.remove = spear_thermal_exit,
	197	.driver = {
	198	.name = "spear_thermal",
	199	.owner = THIS_MODULE,
	200	.pm = &spear_thermal_pm_ops,
5454f211	201	.of_match_table = spear_thermal_id_table,
6a92c366 VF	202	},
	203	};
	204
	205	module_platform_driver(spear_thermal_driver);
	206
	207	MODULE_AUTHOR("Vincenzo Frascino <vincenzo.frascino@st.com>");
	208	MODULE_DESCRIPTION("SPEAr thermal driver");
	209	MODULE_LICENSE("GPL");