1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2017 Rafał Miłecki <rafal@milecki.pl> 4 */ 5 6 #include <linux/module.h> 7 #include <linux/of_address.h> 8 #include <linux/platform_device.h> 9 #include <linux/thermal.h> 10 11 #define PVTMON_CONTROL0 0x00 12 #define PVTMON_CONTROL0_SEL_MASK 0x0000000e 13 #define PVTMON_CONTROL0_SEL_TEMP_MONITOR 0x00000000 14 #define PVTMON_CONTROL0_SEL_TEST_MODE 0x0000000e 15 #define PVTMON_STATUS 0x08 16 17 struct ns_thermal { 18 struct thermal_zone_device *tz; 19 void __iomem *pvtmon; 20 }; 21 22 static int ns_thermal_get_temp(void *data, int *temp) 23 { 24 struct ns_thermal *ns_thermal = data; 25 int offset = thermal_zone_get_offset(ns_thermal->tz); 26 int slope = thermal_zone_get_slope(ns_thermal->tz); 27 u32 val; 28 29 val = readl(ns_thermal->pvtmon + PVTMON_CONTROL0); 30 if ((val & PVTMON_CONTROL0_SEL_MASK) != PVTMON_CONTROL0_SEL_TEMP_MONITOR) { 31 /* Clear current mode selection */ 32 val &= ~PVTMON_CONTROL0_SEL_MASK; 33 34 /* Set temp monitor mode (it's the default actually) */ 35 val |= PVTMON_CONTROL0_SEL_TEMP_MONITOR; 36 37 writel(val, ns_thermal->pvtmon + PVTMON_CONTROL0); 38 } 39 40 val = readl(ns_thermal->pvtmon + PVTMON_STATUS); 41 *temp = slope * val + offset; 42 43 return 0; 44 } 45 46 static const struct thermal_zone_of_device_ops ns_thermal_ops = { 47 .get_temp = ns_thermal_get_temp, 48 }; 49 50 static int ns_thermal_probe(struct platform_device *pdev) 51 { 52 struct device *dev = &pdev->dev; 53 struct ns_thermal *ns_thermal; 54 55 ns_thermal = devm_kzalloc(dev, sizeof(*ns_thermal), GFP_KERNEL); 56 if (!ns_thermal) 57 return -ENOMEM; 58 59 ns_thermal->pvtmon = of_iomap(dev_of_node(dev), 0); 60 if (WARN_ON(!ns_thermal->pvtmon)) 61 return -ENOENT; 62 63 ns_thermal->tz = devm_thermal_zone_of_sensor_register(dev, 0, 64 ns_thermal, 65 &ns_thermal_ops); 66 if (IS_ERR(ns_thermal->tz)) { 67 iounmap(ns_thermal->pvtmon); 68 return PTR_ERR(ns_thermal->tz); 69 } 70 71 platform_set_drvdata(pdev, ns_thermal); 72 73 return 0; 74 } 75 76 static int ns_thermal_remove(struct platform_device *pdev) 77 { 78 struct ns_thermal *ns_thermal = platform_get_drvdata(pdev); 79 80 iounmap(ns_thermal->pvtmon); 81 82 return 0; 83 } 84 85 static const struct of_device_id ns_thermal_of_match[] = { 86 { .compatible = "brcm,ns-thermal", }, 87 {}, 88 }; 89 MODULE_DEVICE_TABLE(of, ns_thermal_of_match); 90 91 static struct platform_driver ns_thermal_driver = { 92 .probe = ns_thermal_probe, 93 .remove = ns_thermal_remove, 94 .driver = { 95 .name = "ns-thermal", 96 .of_match_table = ns_thermal_of_match, 97 }, 98 }; 99 module_platform_driver(ns_thermal_driver); 100 101 MODULE_AUTHOR("Rafał Miłecki <rafal@milecki.pl>"); 102 MODULE_DESCRIPTION("Northstar thermal driver"); 103 MODULE_LICENSE("GPL v2"); 104