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 47 return IRQ_HANDLED; 48 } 49 50 /* Private ops for the Memory Mapped based thermal sensors */ 51 static int st_mmap_power_ctrl(struct st_thermal_sensor *sensor, 52 enum st_thermal_power_state power_state) 53 { 54 const unsigned int mask = (THERMAL_PDN | THERMAL_SRSTN); 55 const unsigned int val = power_state ? mask : 0; 56 57 return regmap_update_bits(sensor->regmap, STIH416_MPE_CONF, mask, val); 58 } 59 60 static int st_mmap_alloc_regfields(struct st_thermal_sensor *sensor) 61 { 62 struct device *dev = sensor->dev; 63 struct regmap *regmap = sensor->regmap; 64 const struct reg_field *reg_fields = sensor->cdata->reg_fields; 65 66 sensor->int_thresh_hi = devm_regmap_field_alloc(dev, regmap, 67 reg_fields[INT_THRESH_HI]); 68 sensor->int_enable = devm_regmap_field_alloc(dev, regmap, 69 reg_fields[INT_ENABLE]); 70 71 if (IS_ERR(sensor->int_thresh_hi) || IS_ERR(sensor->int_enable)) { 72 dev_err(dev, "failed to alloc mmap regfields\n"); 73 return -EINVAL; 74 } 75 76 return 0; 77 } 78 79 static int st_mmap_enable_irq(struct st_thermal_sensor *sensor) 80 { 81 int ret; 82 83 /* Set upper critical threshold */ 84 ret = regmap_field_write(sensor->int_thresh_hi, 85 sensor->cdata->crit_temp - 86 sensor->cdata->temp_adjust_val); 87 if (ret) 88 return ret; 89 90 return regmap_field_write(sensor->int_enable, 1); 91 } 92 93 static int st_mmap_register_enable_irq(struct st_thermal_sensor *sensor) 94 { 95 struct device *dev = sensor->dev; 96 struct platform_device *pdev = to_platform_device(dev); 97 int ret; 98 99 sensor->irq = platform_get_irq(pdev, 0); 100 if (sensor->irq < 0) { 101 dev_err(dev, "failed to register IRQ\n"); 102 return sensor->irq; 103 } 104 105 ret = devm_request_threaded_irq(dev, sensor->irq, 106 NULL, st_mmap_thermal_trip_handler, 107 IRQF_TRIGGER_RISING | IRQF_ONESHOT, 108 dev->driver->name, sensor); 109 if (ret) { 110 dev_err(dev, "failed to register IRQ %d\n", sensor->irq); 111 return ret; 112 } 113 114 return st_mmap_enable_irq(sensor); 115 } 116 117 static const struct regmap_config st_416mpe_regmap_config = { 118 .reg_bits = 32, 119 .val_bits = 32, 120 .reg_stride = 4, 121 }; 122 123 static int st_mmap_regmap_init(struct st_thermal_sensor *sensor) 124 { 125 struct device *dev = sensor->dev; 126 struct platform_device *pdev = to_platform_device(dev); 127 struct resource *res; 128 129 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 130 if (!res) { 131 dev_err(dev, "no memory resources defined\n"); 132 return -ENODEV; 133 } 134 135 sensor->mmio_base = devm_ioremap_resource(dev, res); 136 if (IS_ERR(sensor->mmio_base)) { 137 dev_err(dev, "failed to remap IO\n"); 138 return PTR_ERR(sensor->mmio_base); 139 } 140 141 sensor->regmap = devm_regmap_init_mmio(dev, sensor->mmio_base, 142 &st_416mpe_regmap_config); 143 if (IS_ERR(sensor->regmap)) { 144 dev_err(dev, "failed to initialise regmap\n"); 145 return PTR_ERR(sensor->regmap); 146 } 147 148 return 0; 149 } 150 151 static const struct st_thermal_sensor_ops st_mmap_sensor_ops = { 152 .power_ctrl = st_mmap_power_ctrl, 153 .alloc_regfields = st_mmap_alloc_regfields, 154 .regmap_init = st_mmap_regmap_init, 155 .register_enable_irq = st_mmap_register_enable_irq, 156 .enable_irq = st_mmap_enable_irq, 157 }; 158 159 /* Compatible device data stih416 mpe thermal sensor */ 160 const struct st_thermal_compat_data st_416mpe_cdata = { 161 .reg_fields = st_mmap_thermal_regfields, 162 .ops = &st_mmap_sensor_ops, 163 .calibration_val = 14, 164 .temp_adjust_val = -95, 165 .crit_temp = 120, 166 }; 167 168 /* Compatible device data stih407 thermal sensor */ 169 const struct st_thermal_compat_data st_407_cdata = { 170 .reg_fields = st_mmap_thermal_regfields, 171 .ops = &st_mmap_sensor_ops, 172 .calibration_val = 16, 173 .temp_adjust_val = -95, 174 .crit_temp = 120, 175 }; 176 177 static struct of_device_id st_mmap_thermal_of_match[] = { 178 { .compatible = "st,stih416-mpe-thermal", .data = &st_416mpe_cdata }, 179 { .compatible = "st,stih407-thermal", .data = &st_407_cdata }, 180 { /* sentinel */ } 181 }; 182 MODULE_DEVICE_TABLE(of, st_mmap_thermal_of_match); 183 184 int st_mmap_probe(struct platform_device *pdev) 185 { 186 return st_thermal_register(pdev, st_mmap_thermal_of_match); 187 } 188 189 int st_mmap_remove(struct platform_device *pdev) 190 { 191 return st_thermal_unregister(pdev); 192 } 193 194 static struct platform_driver st_mmap_thermal_driver = { 195 .driver = { 196 .name = "st_thermal_mmap", 197 .pm = &st_thermal_pm_ops, 198 .of_match_table = st_mmap_thermal_of_match, 199 }, 200 .probe = st_mmap_probe, 201 .remove = st_mmap_remove, 202 }; 203 204 module_platform_driver(st_mmap_thermal_driver); 205 206 MODULE_AUTHOR("STMicroelectronics (R&D) Limited <ajitpal.singh@st.com>"); 207 MODULE_DESCRIPTION("STMicroelectronics STi SoC Thermal Sensor Driver"); 208 MODULE_LICENSE("GPL v2"); 209