xref: /linux/drivers/thermal/st/st_thermal_memmap.c (revision 561add0da6d3d07c9bccb0832fb6ed5619167d26)
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 stih416 mpe thermal sensor */
146 static 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 */
155 static 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 
163 static 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 };
168 MODULE_DEVICE_TABLE(of, st_mmap_thermal_of_match);
169 
170 static int st_mmap_probe(struct platform_device *pdev)
171 {
172 	return st_thermal_register(pdev,  st_mmap_thermal_of_match);
173 }
174 
175 static void st_mmap_remove(struct platform_device *pdev)
176 {
177 	st_thermal_unregister(pdev);
178 }
179 
180 static 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_new	= st_mmap_remove,
188 };
189 
190 module_platform_driver(st_mmap_thermal_driver);
191 
192 MODULE_AUTHOR("STMicroelectronics (R&D) Limited <ajitpal.singh@st.com>");
193 MODULE_DESCRIPTION("STMicroelectronics STi SoC Thermal Sensor Driver");
194 MODULE_LICENSE("GPL v2");
195