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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * SPEAr thermal driver.4 *5 * Copyright (C) 2011-2012 ST Microelectronics6 * Author: Vincenzo Frascino <vincenzo.frascino@st.com>7 */8 9#include <linux/clk.h>10#include <linux/device.h>11#include <linux/err.h>12#include <linux/io.h>13#include <linux/kernel.h>14#include <linux/of.h>15#include <linux/module.h>16#include <linux/platform_device.h>17#include <linux/thermal.h>18 19#define MD_FACTOR 100020 21/* SPEAr Thermal Sensor Dev Structure */22struct spear_thermal_dev {23 /* pointer to base address of the thermal sensor */24 void __iomem *thermal_base;25 /* clk structure */26 struct clk *clk;27 /* pointer to thermal flags */28 unsigned int flags;29};30 31static inline int thermal_get_temp(struct thermal_zone_device *thermal,32 int *temp)33{34 struct spear_thermal_dev *stdev = thermal_zone_device_priv(thermal);35 36 /*37 * Data are ready to be read after 628 usec from POWERDOWN signal38 * (PDN) = 139 */40 *temp = (readl_relaxed(stdev->thermal_base) & 0x7F) * MD_FACTOR;41 return 0;42}43 44static struct thermal_zone_device_ops ops = {45 .get_temp = thermal_get_temp,46};47 48static int __maybe_unused spear_thermal_suspend(struct device *dev)49{50 struct thermal_zone_device *spear_thermal = dev_get_drvdata(dev);51 struct spear_thermal_dev *stdev = thermal_zone_device_priv(spear_thermal);52 unsigned int actual_mask = 0;53 54 /* Disable SPEAr Thermal Sensor */55 actual_mask = readl_relaxed(stdev->thermal_base);56 writel_relaxed(actual_mask & ~stdev->flags, stdev->thermal_base);57 58 clk_disable(stdev->clk);59 dev_info(dev, "Suspended.\n");60 61 return 0;62}63 64static int __maybe_unused spear_thermal_resume(struct device *dev)65{66 struct thermal_zone_device *spear_thermal = dev_get_drvdata(dev);67 struct spear_thermal_dev *stdev = thermal_zone_device_priv(spear_thermal);68 unsigned int actual_mask = 0;69 int ret = 0;70 71 ret = clk_enable(stdev->clk);72 if (ret) {73 dev_err(dev, "Can't enable clock\n");74 return ret;75 }76 77 /* Enable SPEAr Thermal Sensor */78 actual_mask = readl_relaxed(stdev->thermal_base);79 writel_relaxed(actual_mask | stdev->flags, stdev->thermal_base);80 81 dev_info(dev, "Resumed.\n");82 83 return 0;84}85 86static SIMPLE_DEV_PM_OPS(spear_thermal_pm_ops, spear_thermal_suspend,87 spear_thermal_resume);88 89static int spear_thermal_probe(struct platform_device *pdev)90{91 struct thermal_zone_device *spear_thermal = NULL;92 struct spear_thermal_dev *stdev;93 struct device_node *np = pdev->dev.of_node;94 int ret = 0, val;95 96 if (!np || !of_property_read_u32(np, "st,thermal-flags", &val)) {97 dev_err(&pdev->dev, "Failed: DT Pdata not passed\n");98 return -EINVAL;99 }100 101 stdev = devm_kzalloc(&pdev->dev, sizeof(*stdev), GFP_KERNEL);102 if (!stdev)103 return -ENOMEM;104 105 /* Enable thermal sensor */106 stdev->thermal_base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);107 if (IS_ERR(stdev->thermal_base))108 return PTR_ERR(stdev->thermal_base);109 110 stdev->clk = devm_clk_get(&pdev->dev, NULL);111 if (IS_ERR(stdev->clk)) {112 dev_err(&pdev->dev, "Can't get clock\n");113 return PTR_ERR(stdev->clk);114 }115 116 ret = clk_enable(stdev->clk);117 if (ret) {118 dev_err(&pdev->dev, "Can't enable clock\n");119 return ret;120 }121 122 stdev->flags = val;123 writel_relaxed(stdev->flags, stdev->thermal_base);124 125 spear_thermal = thermal_tripless_zone_device_register("spear_thermal",126 stdev, &ops, NULL);127 if (IS_ERR(spear_thermal)) {128 dev_err(&pdev->dev, "thermal zone device is NULL\n");129 ret = PTR_ERR(spear_thermal);130 goto disable_clk;131 }132 ret = thermal_zone_device_enable(spear_thermal);133 if (ret) {134 dev_err(&pdev->dev, "Cannot enable thermal zone\n");135 goto unregister_tzd;136 }137 138 platform_set_drvdata(pdev, spear_thermal);139 140 dev_info(&pdev->dev, "Thermal Sensor Loaded at: 0x%p.\n",141 stdev->thermal_base);142 143 return 0;144 145unregister_tzd:146 thermal_zone_device_unregister(spear_thermal);147disable_clk:148 clk_disable(stdev->clk);149 150 return ret;151}152 153static void spear_thermal_exit(struct platform_device *pdev)154{155 unsigned int actual_mask = 0;156 struct thermal_zone_device *spear_thermal = platform_get_drvdata(pdev);157 struct spear_thermal_dev *stdev = thermal_zone_device_priv(spear_thermal);158 159 thermal_zone_device_unregister(spear_thermal);160 161 /* Disable SPEAr Thermal Sensor */162 actual_mask = readl_relaxed(stdev->thermal_base);163 writel_relaxed(actual_mask & ~stdev->flags, stdev->thermal_base);164 165 clk_disable(stdev->clk);166}167 168static const struct of_device_id spear_thermal_id_table[] = {169 { .compatible = "st,thermal-spear1340" },170 {}171};172MODULE_DEVICE_TABLE(of, spear_thermal_id_table);173 174static struct platform_driver spear_thermal_driver = {175 .probe = spear_thermal_probe,176 .remove_new = spear_thermal_exit,177 .driver = {178 .name = "spear_thermal",179 .pm = &spear_thermal_pm_ops,180 .of_match_table = spear_thermal_id_table,181 },182};183 184module_platform_driver(spear_thermal_driver);185 186MODULE_AUTHOR("Vincenzo Frascino <vincenzo.frascino@st.com>");187MODULE_DESCRIPTION("SPEAr thermal driver");188MODULE_LICENSE("GPL");189