kernel/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
  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 static 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 static 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 const 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 static int st_mmap_probe(struct platform_device *pdev)
 185 {
 186         return st_thermal_register(pdev,  st_mmap_thermal_of_match);
 187 }
 188
 189 static 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");