1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * ST Thermal Sensor Driver for memory mapped sensors. 4 * Author: Ajit Pal Singh <ajitpal.singh@st.com> 5 * 6 * Copyright (C) 2003-2014 STMicroelectronics (R&D) Limited 7 */ 8 9 #include <linux/of.h> 10 #include <linux/module.h> 11 12 #include "st_thermal.h" 13 14 #define STIH416_MPE_CONF 0x0 15 #define STIH416_MPE_STATUS 0x4 16 #define STIH416_MPE_INT_THRESH 0x8 17 #define STIH416_MPE_INT_EN 0xC 18 19 /* Power control bits for the memory mapped thermal sensor */ 20 #define THERMAL_PDN BIT(4) 21 #define THERMAL_SRSTN BIT(10) 22 23 static const struct reg_field st_mmap_thermal_regfields[MAX_REGFIELDS] = { 24 /* 25 * According to the STIH416 MPE temp sensor data sheet - 26 * the PDN (Power Down Bit) and SRSTN (Soft Reset Bit) need to be 27 * written simultaneously for powering on and off the temperature 28 * sensor. regmap_update_bits() will be used to update the register. 29 */ 30 [INT_THRESH_HI] = REG_FIELD(STIH416_MPE_INT_THRESH, 0, 7), 31 [DCORRECT] = REG_FIELD(STIH416_MPE_CONF, 5, 9), 32 [OVERFLOW] = REG_FIELD(STIH416_MPE_STATUS, 9, 9), 33 [DATA] = REG_FIELD(STIH416_MPE_STATUS, 11, 18), 34 [INT_ENABLE] = REG_FIELD(STIH416_MPE_INT_EN, 0, 0), 35 }; 36 37 static irqreturn_t st_mmap_thermal_trip_handler(int irq, void *sdata) 38 { 39 struct st_thermal_sensor *sensor = sdata; 40 41 thermal_zone_device_update(sensor->thermal_dev, 42 THERMAL_EVENT_UNSPECIFIED); 43 44 return IRQ_HANDLED; 45 } 46 47 /* Private ops for the Memory Mapped based thermal sensors */ 48 static int st_mmap_power_ctrl(struct st_thermal_sensor *sensor, 49 enum st_thermal_power_state power_state) 50 { 51 const unsigned int mask = (THERMAL_PDN | THERMAL_SRSTN); 52 const unsigned int val = power_state ? mask : 0; 53 54 return regmap_update_bits(sensor->regmap, STIH416_MPE_CONF, mask, val); 55 } 56 57 static int st_mmap_alloc_regfields(struct st_thermal_sensor *sensor) 58 { 59 struct device *dev = sensor->dev; 60 struct regmap *regmap = sensor->regmap; 61 const struct reg_field *reg_fields = sensor->cdata->reg_fields; 62 63 sensor->int_thresh_hi = devm_regmap_field_alloc(dev, regmap, 64 reg_fields[INT_THRESH_HI]); 65 sensor->int_enable = devm_regmap_field_alloc(dev, regmap, 66 reg_fields[INT_ENABLE]); 67 68 if (IS_ERR(sensor->int_thresh_hi) || IS_ERR(sensor->int_enable)) { 69 dev_err(dev, "failed to alloc mmap regfields\n"); 70 return -EINVAL; 71 } 72 73 return 0; 74 } 75 76 static int st_mmap_enable_irq(struct st_thermal_sensor *sensor) 77 { 78 int ret; 79 80 /* Set upper critical threshold */ 81 ret = regmap_field_write(sensor->int_thresh_hi, 82 sensor->cdata->crit_temp - 83 sensor->cdata->temp_adjust_val); 84 if (ret) 85 return ret; 86 87 return regmap_field_write(sensor->int_enable, 1); 88 } 89 90 static int st_mmap_register_enable_irq(struct st_thermal_sensor *sensor) 91 { 92 struct device *dev = sensor->dev; 93 struct platform_device *pdev = to_platform_device(dev); 94 int ret; 95 96 sensor->irq = platform_get_irq(pdev, 0); 97 if (sensor->irq < 0) 98 return sensor->irq; 99 100 ret = devm_request_threaded_irq(dev, sensor->irq, 101 NULL, st_mmap_thermal_trip_handler, 102 IRQF_TRIGGER_RISING | IRQF_ONESHOT, 103 dev->driver->name, sensor); 104 if (ret) { 105 dev_err(dev, "failed to register IRQ %d\n", sensor->irq); 106 return ret; 107 } 108 109 return st_mmap_enable_irq(sensor); 110 } 111 112 static const struct regmap_config st_416mpe_regmap_config = { 113 .reg_bits = 32, 114 .val_bits = 32, 115 .reg_stride = 4, 116 }; 117 118 static int st_mmap_regmap_init(struct st_thermal_sensor *sensor) 119 { 120 struct device *dev = sensor->dev; 121 struct platform_device *pdev = to_platform_device(dev); 122 123 sensor->mmio_base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL); 124 if (IS_ERR(sensor->mmio_base)) 125 return PTR_ERR(sensor->mmio_base); 126 127 sensor->regmap = devm_regmap_init_mmio(dev, sensor->mmio_base, 128 &st_416mpe_regmap_config); 129 if (IS_ERR(sensor->regmap)) { 130 dev_err(dev, "failed to initialise regmap\n"); 131 return PTR_ERR(sensor->regmap); 132 } 133 134 return 0; 135 } 136 137 static const struct st_thermal_sensor_ops st_mmap_sensor_ops = { 138 .power_ctrl = st_mmap_power_ctrl, 139 .alloc_regfields = st_mmap_alloc_regfields, 140 .regmap_init = st_mmap_regmap_init, 141 .register_enable_irq = st_mmap_register_enable_irq, 142 .enable_irq = st_mmap_enable_irq, 143 }; 144 145 /* Compatible device data stih407 thermal sensor */ 146 static const struct st_thermal_compat_data st_407_cdata = { 147 .reg_fields = st_mmap_thermal_regfields, 148 .ops = &st_mmap_sensor_ops, 149 .calibration_val = 16, 150 .temp_adjust_val = -95, 151 .crit_temp = 120, 152 }; 153 154 static const struct of_device_id st_mmap_thermal_of_match[] = { 155 { .compatible = "st,stih407-thermal", .data = &st_407_cdata }, 156 { /* sentinel */ } 157 }; 158 MODULE_DEVICE_TABLE(of, st_mmap_thermal_of_match); 159 160 static int st_mmap_probe(struct platform_device *pdev) 161 { 162 return st_thermal_register(pdev, st_mmap_thermal_of_match); 163 } 164 165 static void st_mmap_remove(struct platform_device *pdev) 166 { 167 st_thermal_unregister(pdev); 168 } 169 170 static struct platform_driver st_mmap_thermal_driver = { 171 .driver = { 172 .name = "st_thermal_mmap", 173 .pm = &st_thermal_pm_ops, 174 .of_match_table = st_mmap_thermal_of_match, 175 }, 176 .probe = st_mmap_probe, 177 .remove_new = st_mmap_remove, 178 }; 179 180 module_platform_driver(st_mmap_thermal_driver); 181 182 MODULE_AUTHOR("STMicroelectronics (R&D) Limited <ajitpal.singh@st.com>"); 183 MODULE_DESCRIPTION("STMicroelectronics STi SoC Thermal Sensor Driver"); 184 MODULE_LICENSE("GPL v2"); 185