drivers/thermal/st/st_thermal_memmap.c

   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");