Loading...
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 | /*
* 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,
int *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 *res;
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;
}
stdev = devm_kzalloc(&pdev->dev, sizeof(*stdev), GFP_KERNEL);
if (!stdev)
return -ENOMEM;
/* Enable thermal sensor */
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
stdev->thermal_base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(stdev->thermal_base))
return PTR_ERR(stdev->thermal_base);
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);
/* 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",
.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");
|