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Diffstat (limited to '')
| -rw-r--r-- | drivers/thermal/st/st_thermal_memmap.c | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/drivers/thermal/st/st_thermal_memmap.c b/drivers/thermal/st/st_thermal_memmap.c new file mode 100644 index 000000000..91d42319d --- /dev/null +++ b/drivers/thermal/st/st_thermal_memmap.c @@ -0,0 +1,209 @@ +/* + * ST Thermal Sensor Driver for memory mapped sensors. + * Author: Ajit Pal Singh <ajitpal.singh@st.com> + * + * Copyright (C) 2003-2014 STMicroelectronics (R&D) Limited + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/of.h> +#include <linux/module.h> + +#include "st_thermal.h" + +#define STIH416_MPE_CONF 0x0 +#define STIH416_MPE_STATUS 0x4 +#define STIH416_MPE_INT_THRESH 0x8 +#define STIH416_MPE_INT_EN 0xC + +/* Power control bits for the memory mapped thermal sensor */ +#define THERMAL_PDN BIT(4) +#define THERMAL_SRSTN BIT(10) + +static const struct reg_field st_mmap_thermal_regfields[MAX_REGFIELDS] = { + /* + * According to the STIH416 MPE temp sensor data sheet - + * the PDN (Power Down Bit) and SRSTN (Soft Reset Bit) need to be + * written simultaneously for powering on and off the temperature + * sensor. regmap_update_bits() will be used to update the register. + */ + [INT_THRESH_HI] = REG_FIELD(STIH416_MPE_INT_THRESH, 0, 7), + [DCORRECT] = REG_FIELD(STIH416_MPE_CONF, 5, 9), + [OVERFLOW] = REG_FIELD(STIH416_MPE_STATUS, 9, 9), + [DATA] = REG_FIELD(STIH416_MPE_STATUS, 11, 18), + [INT_ENABLE] = REG_FIELD(STIH416_MPE_INT_EN, 0, 0), +}; + +static irqreturn_t st_mmap_thermal_trip_handler(int irq, void *sdata) +{ + struct st_thermal_sensor *sensor = sdata; + + thermal_zone_device_update(sensor->thermal_dev, + THERMAL_EVENT_UNSPECIFIED); + + return IRQ_HANDLED; +} + +/* Private ops for the Memory Mapped based thermal sensors */ +static int st_mmap_power_ctrl(struct st_thermal_sensor *sensor, + enum st_thermal_power_state power_state) +{ + const unsigned int mask = (THERMAL_PDN | THERMAL_SRSTN); + const unsigned int val = power_state ? mask : 0; + + return regmap_update_bits(sensor->regmap, STIH416_MPE_CONF, mask, val); +} + +static int st_mmap_alloc_regfields(struct st_thermal_sensor *sensor) +{ + struct device *dev = sensor->dev; + struct regmap *regmap = sensor->regmap; + const struct reg_field *reg_fields = sensor->cdata->reg_fields; + + sensor->int_thresh_hi = devm_regmap_field_alloc(dev, regmap, + reg_fields[INT_THRESH_HI]); + sensor->int_enable = devm_regmap_field_alloc(dev, regmap, + reg_fields[INT_ENABLE]); + + if (IS_ERR(sensor->int_thresh_hi) || IS_ERR(sensor->int_enable)) { + dev_err(dev, "failed to alloc mmap regfields\n"); + return -EINVAL; + } + + return 0; +} + +static int st_mmap_enable_irq(struct st_thermal_sensor *sensor) +{ + int ret; + + /* Set upper critical threshold */ + ret = regmap_field_write(sensor->int_thresh_hi, + sensor->cdata->crit_temp - + sensor->cdata->temp_adjust_val); + if (ret) + return ret; + + return regmap_field_write(sensor->int_enable, 1); +} + +static int st_mmap_register_enable_irq(struct st_thermal_sensor *sensor) +{ + struct device *dev = sensor->dev; + struct platform_device *pdev = to_platform_device(dev); + int ret; + + sensor->irq = platform_get_irq(pdev, 0); + if (sensor->irq < 0) { + dev_err(dev, "failed to register IRQ\n"); + return sensor->irq; + } + + ret = devm_request_threaded_irq(dev, sensor->irq, + NULL, st_mmap_thermal_trip_handler, + IRQF_TRIGGER_RISING | IRQF_ONESHOT, + dev->driver->name, sensor); + if (ret) { + dev_err(dev, "failed to register IRQ %d\n", sensor->irq); + return ret; + } + + return st_mmap_enable_irq(sensor); +} + +static const struct regmap_config st_416mpe_regmap_config = { + .reg_bits = 32, + .val_bits = 32, + .reg_stride = 4, +}; + +static int st_mmap_regmap_init(struct st_thermal_sensor *sensor) +{ + struct device *dev = sensor->dev; + struct platform_device *pdev = to_platform_device(dev); + struct resource *res; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(dev, "no memory resources defined\n"); + return -ENODEV; + } + + sensor->mmio_base = devm_ioremap_resource(dev, res); + if (IS_ERR(sensor->mmio_base)) { + dev_err(dev, "failed to remap IO\n"); + return PTR_ERR(sensor->mmio_base); + } + + sensor->regmap = devm_regmap_init_mmio(dev, sensor->mmio_base, + &st_416mpe_regmap_config); + if (IS_ERR(sensor->regmap)) { + dev_err(dev, "failed to initialise regmap\n"); + return PTR_ERR(sensor->regmap); + } + + return 0; +} + +static const struct st_thermal_sensor_ops st_mmap_sensor_ops = { + .power_ctrl = st_mmap_power_ctrl, + .alloc_regfields = st_mmap_alloc_regfields, + .regmap_init = st_mmap_regmap_init, + .register_enable_irq = st_mmap_register_enable_irq, + .enable_irq = st_mmap_enable_irq, +}; + +/* Compatible device data stih416 mpe thermal sensor */ +static const struct st_thermal_compat_data st_416mpe_cdata = { + .reg_fields = st_mmap_thermal_regfields, + .ops = &st_mmap_sensor_ops, + .calibration_val = 14, + .temp_adjust_val = -95, + .crit_temp = 120, +}; + +/* Compatible device data stih407 thermal sensor */ +static const struct st_thermal_compat_data st_407_cdata = { + .reg_fields = st_mmap_thermal_regfields, + .ops = &st_mmap_sensor_ops, + .calibration_val = 16, + .temp_adjust_val = -95, + .crit_temp = 120, +}; + +static const struct of_device_id st_mmap_thermal_of_match[] = { + { .compatible = "st,stih416-mpe-thermal", .data = &st_416mpe_cdata }, + { .compatible = "st,stih407-thermal", .data = &st_407_cdata }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, st_mmap_thermal_of_match); + +static int st_mmap_probe(struct platform_device *pdev) +{ + return st_thermal_register(pdev, st_mmap_thermal_of_match); +} + +static int st_mmap_remove(struct platform_device *pdev) +{ + return st_thermal_unregister(pdev); +} + +static struct platform_driver st_mmap_thermal_driver = { + .driver = { + .name = "st_thermal_mmap", + .pm = &st_thermal_pm_ops, + .of_match_table = st_mmap_thermal_of_match, + }, + .probe = st_mmap_probe, + .remove = st_mmap_remove, +}; + +module_platform_driver(st_mmap_thermal_driver); + +MODULE_AUTHOR("STMicroelectronics (R&D) Limited <ajitpal.singh@st.com>"); +MODULE_DESCRIPTION("STMicroelectronics STi SoC Thermal Sensor Driver"); +MODULE_LICENSE("GPL v2"); |