1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Dove thermal sensor driver |
4 | * |
5 | * Copyright (C) 2013 Andrew Lunn <andrew@lunn.ch> |
6 | */ |
7 | #include <linux/device.h> |
8 | #include <linux/err.h> |
9 | #include <linux/io.h> |
10 | #include <linux/kernel.h> |
11 | #include <linux/of.h> |
12 | #include <linux/module.h> |
13 | #include <linux/platform_device.h> |
14 | #include <linux/thermal.h> |
15 | |
16 | #define DOVE_THERMAL_TEMP_OFFSET 1 |
17 | #define DOVE_THERMAL_TEMP_MASK 0x1FF |
18 | |
19 | /* Dove Thermal Manager Control and Status Register */ |
20 | #define PMU_TM_DISABLE_OFFS 0 |
21 | #define PMU_TM_DISABLE_MASK (0x1 << PMU_TM_DISABLE_OFFS) |
22 | |
23 | /* Dove Theraml Diode Control 0 Register */ |
24 | #define PMU_TDC0_SW_RST_MASK (0x1 << 1) |
25 | #define PMU_TDC0_SEL_VCAL_OFFS 5 |
26 | #define PMU_TDC0_SEL_VCAL_MASK (0x3 << PMU_TDC0_SEL_VCAL_OFFS) |
27 | #define PMU_TDC0_REF_CAL_CNT_OFFS 11 |
28 | #define PMU_TDC0_REF_CAL_CNT_MASK (0x1FF << PMU_TDC0_REF_CAL_CNT_OFFS) |
29 | #define PMU_TDC0_AVG_NUM_OFFS 25 |
30 | #define PMU_TDC0_AVG_NUM_MASK (0x7 << PMU_TDC0_AVG_NUM_OFFS) |
31 | |
32 | /* Dove Thermal Diode Control 1 Register */ |
33 | #define PMU_TEMP_DIOD_CTRL1_REG 0x04 |
34 | #define PMU_TDC1_TEMP_VALID_MASK (0x1 << 10) |
35 | |
36 | /* Dove Thermal Sensor Dev Structure */ |
37 | struct dove_thermal_priv { |
38 | void __iomem *sensor; |
39 | void __iomem *control; |
40 | }; |
41 | |
42 | static int dove_init_sensor(const struct dove_thermal_priv *priv) |
43 | { |
44 | u32 reg; |
45 | u32 i; |
46 | |
47 | /* Configure the Diode Control Register #0 */ |
48 | reg = readl_relaxed(priv->control); |
49 | |
50 | /* Use average of 2 */ |
51 | reg &= ~PMU_TDC0_AVG_NUM_MASK; |
52 | reg |= (0x1 << PMU_TDC0_AVG_NUM_OFFS); |
53 | |
54 | /* Reference calibration value */ |
55 | reg &= ~PMU_TDC0_REF_CAL_CNT_MASK; |
56 | reg |= (0x0F1 << PMU_TDC0_REF_CAL_CNT_OFFS); |
57 | |
58 | /* Set the high level reference for calibration */ |
59 | reg &= ~PMU_TDC0_SEL_VCAL_MASK; |
60 | reg |= (0x2 << PMU_TDC0_SEL_VCAL_OFFS); |
61 | writel(val: reg, addr: priv->control); |
62 | |
63 | /* Reset the sensor */ |
64 | reg = readl_relaxed(priv->control); |
65 | writel(val: (reg | PMU_TDC0_SW_RST_MASK), addr: priv->control); |
66 | writel(val: reg, addr: priv->control); |
67 | |
68 | /* Enable the sensor */ |
69 | reg = readl_relaxed(priv->sensor); |
70 | reg &= ~PMU_TM_DISABLE_MASK; |
71 | writel(val: reg, addr: priv->sensor); |
72 | |
73 | /* Poll the sensor for the first reading */ |
74 | for (i = 0; i < 1000000; i++) { |
75 | reg = readl_relaxed(priv->sensor); |
76 | if (reg & DOVE_THERMAL_TEMP_MASK) |
77 | break; |
78 | } |
79 | |
80 | if (i == 1000000) |
81 | return -EIO; |
82 | |
83 | return 0; |
84 | } |
85 | |
86 | static int dove_get_temp(struct thermal_zone_device *thermal, |
87 | int *temp) |
88 | { |
89 | unsigned long reg; |
90 | struct dove_thermal_priv *priv = thermal_zone_device_priv(tzd: thermal); |
91 | |
92 | /* Valid check */ |
93 | reg = readl_relaxed(priv->control + PMU_TEMP_DIOD_CTRL1_REG); |
94 | if ((reg & PMU_TDC1_TEMP_VALID_MASK) == 0x0) |
95 | return -EIO; |
96 | |
97 | /* |
98 | * Calculate temperature. According to Marvell internal |
99 | * documentation the formula for this is: |
100 | * Celsius = (322-reg)/1.3625 |
101 | */ |
102 | reg = readl_relaxed(priv->sensor); |
103 | reg = (reg >> DOVE_THERMAL_TEMP_OFFSET) & DOVE_THERMAL_TEMP_MASK; |
104 | *temp = ((3220000000UL - (10000000UL * reg)) / 13625); |
105 | |
106 | return 0; |
107 | } |
108 | |
109 | static struct thermal_zone_device_ops ops = { |
110 | .get_temp = dove_get_temp, |
111 | }; |
112 | |
113 | static const struct of_device_id dove_thermal_id_table[] = { |
114 | { .compatible = "marvell,dove-thermal" }, |
115 | {} |
116 | }; |
117 | |
118 | static int dove_thermal_probe(struct platform_device *pdev) |
119 | { |
120 | struct thermal_zone_device *thermal = NULL; |
121 | struct dove_thermal_priv *priv; |
122 | int ret; |
123 | |
124 | priv = devm_kzalloc(dev: &pdev->dev, size: sizeof(*priv), GFP_KERNEL); |
125 | if (!priv) |
126 | return -ENOMEM; |
127 | |
128 | priv->sensor = devm_platform_get_and_ioremap_resource(pdev, index: 0, NULL); |
129 | if (IS_ERR(ptr: priv->sensor)) |
130 | return PTR_ERR(ptr: priv->sensor); |
131 | |
132 | priv->control = devm_platform_get_and_ioremap_resource(pdev, index: 1, NULL); |
133 | if (IS_ERR(ptr: priv->control)) |
134 | return PTR_ERR(ptr: priv->control); |
135 | |
136 | ret = dove_init_sensor(priv); |
137 | if (ret) { |
138 | dev_err(&pdev->dev, "Failed to initialize sensor\n" ); |
139 | return ret; |
140 | } |
141 | |
142 | thermal = thermal_tripless_zone_device_register(type: "dove_thermal" , devdata: priv, |
143 | ops: &ops, NULL); |
144 | if (IS_ERR(ptr: thermal)) { |
145 | dev_err(&pdev->dev, |
146 | "Failed to register thermal zone device\n" ); |
147 | return PTR_ERR(ptr: thermal); |
148 | } |
149 | |
150 | ret = thermal_zone_device_enable(tz: thermal); |
151 | if (ret) { |
152 | thermal_zone_device_unregister(tz: thermal); |
153 | return ret; |
154 | } |
155 | |
156 | platform_set_drvdata(pdev, data: thermal); |
157 | |
158 | return 0; |
159 | } |
160 | |
161 | static void dove_thermal_exit(struct platform_device *pdev) |
162 | { |
163 | struct thermal_zone_device *dove_thermal = |
164 | platform_get_drvdata(pdev); |
165 | |
166 | thermal_zone_device_unregister(tz: dove_thermal); |
167 | } |
168 | |
169 | MODULE_DEVICE_TABLE(of, dove_thermal_id_table); |
170 | |
171 | static struct platform_driver dove_thermal_driver = { |
172 | .probe = dove_thermal_probe, |
173 | .remove_new = dove_thermal_exit, |
174 | .driver = { |
175 | .name = "dove_thermal" , |
176 | .of_match_table = dove_thermal_id_table, |
177 | }, |
178 | }; |
179 | |
180 | module_platform_driver(dove_thermal_driver); |
181 | |
182 | MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>" ); |
183 | MODULE_DESCRIPTION("Dove thermal driver" ); |
184 | MODULE_LICENSE("GPL" ); |
185 | |