drivers/thermal/st/st_thermal_memmap.c

   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     = pm_sleep_ptr(&st_thermal_pm_ops),
 174                 .of_match_table = st_mmap_thermal_of_match,
 175         },
 176         .probe          = st_mmap_probe,
 177         .remove         = 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");