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");