linux/drivers/thermal/st/st_thermal_memmap.c
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   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
  23static 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
  37static 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 */
  48static 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
  57static 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
  76static 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
  90static 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
 112static const struct regmap_config st_416mpe_regmap_config = {
 113        .reg_bits = 32,
 114        .val_bits = 32,
 115        .reg_stride = 4,
 116};
 117
 118static 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
 137static 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 stih416 mpe thermal sensor */
 146static const struct st_thermal_compat_data st_416mpe_cdata = {
 147        .reg_fields             = st_mmap_thermal_regfields,
 148        .ops                    = &st_mmap_sensor_ops,
 149        .calibration_val        = 14,
 150        .temp_adjust_val        = -95,
 151        .crit_temp              = 120,
 152};
 153
 154/* Compatible device data stih407 thermal sensor */
 155static const struct st_thermal_compat_data st_407_cdata = {
 156        .reg_fields             = st_mmap_thermal_regfields,
 157        .ops                    = &st_mmap_sensor_ops,
 158        .calibration_val        = 16,
 159        .temp_adjust_val        = -95,
 160        .crit_temp              = 120,
 161};
 162
 163static const struct of_device_id st_mmap_thermal_of_match[] = {
 164        { .compatible = "st,stih416-mpe-thermal", .data = &st_416mpe_cdata },
 165        { .compatible = "st,stih407-thermal",     .data = &st_407_cdata },
 166        { /* sentinel */ }
 167};
 168MODULE_DEVICE_TABLE(of, st_mmap_thermal_of_match);
 169
 170static int st_mmap_probe(struct platform_device *pdev)
 171{
 172        return st_thermal_register(pdev,  st_mmap_thermal_of_match);
 173}
 174
 175static int st_mmap_remove(struct platform_device *pdev)
 176{
 177        return st_thermal_unregister(pdev);
 178}
 179
 180static struct platform_driver st_mmap_thermal_driver = {
 181        .driver = {
 182                .name   = "st_thermal_mmap",
 183                .pm     = &st_thermal_pm_ops,
 184                .of_match_table = st_mmap_thermal_of_match,
 185        },
 186        .probe          = st_mmap_probe,
 187        .remove         = st_mmap_remove,
 188};
 189
 190module_platform_driver(st_mmap_thermal_driver);
 191
 192MODULE_AUTHOR("STMicroelectronics (R&D) Limited <ajitpal.singh@st.com>");
 193MODULE_DESCRIPTION("STMicroelectronics STi SoC Thermal Sensor Driver");
 194MODULE_LICENSE("GPL v2");
 195