1 /* 2 * ST Thermal Sensor Driver for memory mapped sensors. 3 * Author: Ajit Pal Singh <ajitpal.singh@st.com> 4 * 5 * Copyright (C) 2003-2014 STMicroelectronics (R&D) Limited 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License as published by 9 * the Free Software Foundation; either version 2 of the License, or 10 * (at your option) any later version. 11 */ 12 13 #include <linux/of.h> 14 #include <linux/module.h> 15 16 #include "st_thermal.h" 17 18 #define STIH416_MPE_CONF 0x0 19 #define STIH416_MPE_STATUS 0x4 20 #define STIH416_MPE_INT_THRESH 0x8 21 #define STIH416_MPE_INT_EN 0xC 22 23 /* Power control bits for the memory mapped thermal sensor */ 24 #define THERMAL_PDN BIT(4) 25 #define THERMAL_SRSTN BIT(10) 26 27 static const struct reg_field st_mmap_thermal_regfields[MAX_REGFIELDS] = { 28 /* 29 * According to the STIH416 MPE temp sensor data sheet - 30 * the PDN (Power Down Bit) and SRSTN (Soft Reset Bit) need to be 31 * written simultaneously for powering on and off the temperature 32 * sensor. regmap_update_bits() will be used to update the register. 33 */ 34 [INT_THRESH_HI] = REG_FIELD(STIH416_MPE_INT_THRESH, 0, 7), 35 [DCORRECT] = REG_FIELD(STIH416_MPE_CONF, 5, 9), 36 [OVERFLOW] = REG_FIELD(STIH416_MPE_STATUS, 9, 9), 37 [DATA] = REG_FIELD(STIH416_MPE_STATUS, 11, 18), 38 [INT_ENABLE] = REG_FIELD(STIH416_MPE_INT_EN, 0, 0), 39 }; 40 41 static irqreturn_t st_mmap_thermal_trip_handler(int irq, void *sdata) 42 { 43 struct st_thermal_sensor *sensor = sdata; 44 45 thermal_zone_device_update(sensor->thermal_dev, 46 THERMAL_EVENT_UNSPECIFIED); 47 48 return IRQ_HANDLED; 49 } 50 51 /* Private ops for the Memory Mapped based thermal sensors */ 52 static int st_mmap_power_ctrl(struct st_thermal_sensor *sensor, 53 enum st_thermal_power_state power_state) 54 { 55 const unsigned int mask = (THERMAL_PDN | THERMAL_SRSTN); 56 const unsigned int val = power_state ? mask : 0; 57 58 return regmap_update_bits(sensor->regmap, STIH416_MPE_CONF, mask, val); 59 } 60 61 static int st_mmap_alloc_regfields(struct st_thermal_sensor *sensor) 62 { 63 struct device *dev = sensor->dev; 64 struct regmap *regmap = sensor->regmap; 65 const struct reg_field *reg_fields = sensor->cdata->reg_fields; 66 67 sensor->int_thresh_hi = devm_regmap_field_alloc(dev, regmap, 68 reg_fields[INT_THRESH_HI]); 69 sensor->int_enable = devm_regmap_field_alloc(dev, regmap, 70 reg_fields[INT_ENABLE]); 71 72 if (IS_ERR(sensor->int_thresh_hi) || IS_ERR(sensor->int_enable)) { 73 dev_err(dev, "failed to alloc mmap regfields\n"); 74 return -EINVAL; 75 } 76 77 return 0; 78 } 79 80 static int st_mmap_enable_irq(struct st_thermal_sensor *sensor) 81 { 82 int ret; 83 84 /* Set upper critical threshold */ 85 ret = regmap_field_write(sensor->int_thresh_hi, 86 sensor->cdata->crit_temp - 87 sensor->cdata->temp_adjust_val); 88 if (ret) 89 return ret; 90 91 return regmap_field_write(sensor->int_enable, 1); 92 } 93 94 static int st_mmap_register_enable_irq(struct st_thermal_sensor *sensor) 95 { 96 struct device *dev = sensor->dev; 97 struct platform_device *pdev = to_platform_device(dev); 98 int ret; 99 100 sensor->irq = platform_get_irq(pdev, 0); 101 if (sensor->irq < 0) { 102 dev_err(dev, "failed to register IRQ\n"); 103 return sensor->irq; 104 } 105 106 ret = devm_request_threaded_irq(dev, sensor->irq, 107 NULL, st_mmap_thermal_trip_handler, 108 IRQF_TRIGGER_RISING | IRQF_ONESHOT, 109 dev->driver->name, sensor); 110 if (ret) { 111 dev_err(dev, "failed to register IRQ %d\n", sensor->irq); 112 return ret; 113 } 114 115 return st_mmap_enable_irq(sensor); 116 } 117 118 static const struct regmap_config st_416mpe_regmap_config = { 119 .reg_bits = 32, 120 .val_bits = 32, 121 .reg_stride = 4, 122 }; 123 124 static int st_mmap_regmap_init(struct st_thermal_sensor *sensor) 125 { 126 struct device *dev = sensor->dev; 127 struct platform_device *pdev = to_platform_device(dev); 128 struct resource *res; 129 130 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 131 if (!res) { 132 dev_err(dev, "no memory resources defined\n"); 133 return -ENODEV; 134 } 135 136 sensor->mmio_base = devm_ioremap_resource(dev, res); 137 if (IS_ERR(sensor->mmio_base)) { 138 dev_err(dev, "failed to remap IO\n"); 139 return PTR_ERR(sensor->mmio_base); 140 } 141 142 sensor->regmap = devm_regmap_init_mmio(dev, sensor->mmio_base, 143 &st_416mpe_regmap_config); 144 if (IS_ERR(sensor->regmap)) { 145 dev_err(dev, "failed to initialise regmap\n"); 146 return PTR_ERR(sensor->regmap); 147 } 148 149 return 0; 150 } 151 152 static const struct st_thermal_sensor_ops st_mmap_sensor_ops = { 153 .power_ctrl = st_mmap_power_ctrl, 154 .alloc_regfields = st_mmap_alloc_regfields, 155 .regmap_init = st_mmap_regmap_init, 156 .register_enable_irq = st_mmap_register_enable_irq, 157 .enable_irq = st_mmap_enable_irq, 158 }; 159 160 /* Compatible device data stih416 mpe thermal sensor */ 161 static const struct st_thermal_compat_data st_416mpe_cdata = { 162 .reg_fields = st_mmap_thermal_regfields, 163 .ops = &st_mmap_sensor_ops, 164 .calibration_val = 14, 165 .temp_adjust_val = -95, 166 .crit_temp = 120, 167 }; 168 169 /* Compatible device data stih407 thermal sensor */ 170 static const struct st_thermal_compat_data st_407_cdata = { 171 .reg_fields = st_mmap_thermal_regfields, 172 .ops = &st_mmap_sensor_ops, 173 .calibration_val = 16, 174 .temp_adjust_val = -95, 175 .crit_temp = 120, 176 }; 177 178 static const struct of_device_id st_mmap_thermal_of_match[] = { 179 { .compatible = "st,stih416-mpe-thermal", .data = &st_416mpe_cdata }, 180 { .compatible = "st,stih407-thermal", .data = &st_407_cdata }, 181 { /* sentinel */ } 182 }; 183 MODULE_DEVICE_TABLE(of, st_mmap_thermal_of_match); 184 185 static int st_mmap_probe(struct platform_device *pdev) 186 { 187 return st_thermal_register(pdev, st_mmap_thermal_of_match); 188 } 189 190 static int st_mmap_remove(struct platform_device *pdev) 191 { 192 return st_thermal_unregister(pdev); 193 } 194 195 static struct platform_driver st_mmap_thermal_driver = { 196 .driver = { 197 .name = "st_thermal_mmap", 198 .pm = &st_thermal_pm_ops, 199 .of_match_table = st_mmap_thermal_of_match, 200 }, 201 .probe = st_mmap_probe, 202 .remove = st_mmap_remove, 203 }; 204 205 module_platform_driver(st_mmap_thermal_driver); 206 207 MODULE_AUTHOR("STMicroelectronics (R&D) Limited <ajitpal.singh@st.com>"); 208 MODULE_DESCRIPTION("STMicroelectronics STi SoC Thermal Sensor Driver"); 209 MODULE_LICENSE("GPL v2"); 210