1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * SPEAr thermal driver. |
4 | * |
5 | * Copyright (C) 2011-2012 ST Microelectronics |
6 | * Author: Vincenzo Frascino <vincenzo.frascino@st.com> |
7 | */ |
8 | |
9 | #include <linux/clk.h> |
10 | #include <linux/device.h> |
11 | #include <linux/err.h> |
12 | #include <linux/io.h> |
13 | #include <linux/kernel.h> |
14 | #include <linux/of.h> |
15 | #include <linux/module.h> |
16 | #include <linux/platform_device.h> |
17 | #include <linux/thermal.h> |
18 | |
19 | #define MD_FACTOR 1000 |
20 | |
21 | /* SPEAr Thermal Sensor Dev Structure */ |
22 | struct spear_thermal_dev { |
23 | /* pointer to base address of the thermal sensor */ |
24 | void __iomem *thermal_base; |
25 | /* clk structure */ |
26 | struct clk *clk; |
27 | /* pointer to thermal flags */ |
28 | unsigned int flags; |
29 | }; |
30 | |
31 | static inline int thermal_get_temp(struct thermal_zone_device *thermal, |
32 | int *temp) |
33 | { |
34 | struct spear_thermal_dev *stdev = thermal_zone_device_priv(tzd: thermal); |
35 | |
36 | /* |
37 | * Data are ready to be read after 628 usec from POWERDOWN signal |
38 | * (PDN) = 1 |
39 | */ |
40 | *temp = (readl_relaxed(stdev->thermal_base) & 0x7F) * MD_FACTOR; |
41 | return 0; |
42 | } |
43 | |
44 | static struct thermal_zone_device_ops ops = { |
45 | .get_temp = thermal_get_temp, |
46 | }; |
47 | |
48 | static int __maybe_unused spear_thermal_suspend(struct device *dev) |
49 | { |
50 | struct thermal_zone_device *spear_thermal = dev_get_drvdata(dev); |
51 | struct spear_thermal_dev *stdev = thermal_zone_device_priv(tzd: spear_thermal); |
52 | unsigned int actual_mask = 0; |
53 | |
54 | /* Disable SPEAr Thermal Sensor */ |
55 | actual_mask = readl_relaxed(stdev->thermal_base); |
56 | writel_relaxed(actual_mask & ~stdev->flags, stdev->thermal_base); |
57 | |
58 | clk_disable(clk: stdev->clk); |
59 | dev_info(dev, "Suspended.\n" ); |
60 | |
61 | return 0; |
62 | } |
63 | |
64 | static int __maybe_unused spear_thermal_resume(struct device *dev) |
65 | { |
66 | struct thermal_zone_device *spear_thermal = dev_get_drvdata(dev); |
67 | struct spear_thermal_dev *stdev = thermal_zone_device_priv(tzd: spear_thermal); |
68 | unsigned int actual_mask = 0; |
69 | int ret = 0; |
70 | |
71 | ret = clk_enable(clk: stdev->clk); |
72 | if (ret) { |
73 | dev_err(dev, "Can't enable clock\n" ); |
74 | return ret; |
75 | } |
76 | |
77 | /* Enable SPEAr Thermal Sensor */ |
78 | actual_mask = readl_relaxed(stdev->thermal_base); |
79 | writel_relaxed(actual_mask | stdev->flags, stdev->thermal_base); |
80 | |
81 | dev_info(dev, "Resumed.\n" ); |
82 | |
83 | return 0; |
84 | } |
85 | |
86 | static SIMPLE_DEV_PM_OPS(spear_thermal_pm_ops, spear_thermal_suspend, |
87 | spear_thermal_resume); |
88 | |
89 | static int spear_thermal_probe(struct platform_device *pdev) |
90 | { |
91 | struct thermal_zone_device *spear_thermal = NULL; |
92 | struct spear_thermal_dev *stdev; |
93 | struct device_node *np = pdev->dev.of_node; |
94 | int ret = 0, val; |
95 | |
96 | if (!np || !of_property_read_u32(np, propname: "st,thermal-flags" , out_value: &val)) { |
97 | dev_err(&pdev->dev, "Failed: DT Pdata not passed\n" ); |
98 | return -EINVAL; |
99 | } |
100 | |
101 | stdev = devm_kzalloc(dev: &pdev->dev, size: sizeof(*stdev), GFP_KERNEL); |
102 | if (!stdev) |
103 | return -ENOMEM; |
104 | |
105 | /* Enable thermal sensor */ |
106 | stdev->thermal_base = devm_platform_get_and_ioremap_resource(pdev, index: 0, NULL); |
107 | if (IS_ERR(ptr: stdev->thermal_base)) |
108 | return PTR_ERR(ptr: stdev->thermal_base); |
109 | |
110 | stdev->clk = devm_clk_get(dev: &pdev->dev, NULL); |
111 | if (IS_ERR(ptr: stdev->clk)) { |
112 | dev_err(&pdev->dev, "Can't get clock\n" ); |
113 | return PTR_ERR(ptr: stdev->clk); |
114 | } |
115 | |
116 | ret = clk_enable(clk: stdev->clk); |
117 | if (ret) { |
118 | dev_err(&pdev->dev, "Can't enable clock\n" ); |
119 | return ret; |
120 | } |
121 | |
122 | stdev->flags = val; |
123 | writel_relaxed(stdev->flags, stdev->thermal_base); |
124 | |
125 | spear_thermal = thermal_tripless_zone_device_register(type: "spear_thermal" , |
126 | devdata: stdev, ops: &ops, NULL); |
127 | if (IS_ERR(ptr: spear_thermal)) { |
128 | dev_err(&pdev->dev, "thermal zone device is NULL\n" ); |
129 | ret = PTR_ERR(ptr: spear_thermal); |
130 | goto disable_clk; |
131 | } |
132 | ret = thermal_zone_device_enable(tz: spear_thermal); |
133 | if (ret) { |
134 | dev_err(&pdev->dev, "Cannot enable thermal zone\n" ); |
135 | goto unregister_tzd; |
136 | } |
137 | |
138 | platform_set_drvdata(pdev, data: spear_thermal); |
139 | |
140 | dev_info(&pdev->dev, "Thermal Sensor Loaded at: 0x%p.\n" , |
141 | stdev->thermal_base); |
142 | |
143 | return 0; |
144 | |
145 | unregister_tzd: |
146 | thermal_zone_device_unregister(tz: spear_thermal); |
147 | disable_clk: |
148 | clk_disable(clk: stdev->clk); |
149 | |
150 | return ret; |
151 | } |
152 | |
153 | static void spear_thermal_exit(struct platform_device *pdev) |
154 | { |
155 | unsigned int actual_mask = 0; |
156 | struct thermal_zone_device *spear_thermal = platform_get_drvdata(pdev); |
157 | struct spear_thermal_dev *stdev = thermal_zone_device_priv(tzd: spear_thermal); |
158 | |
159 | thermal_zone_device_unregister(tz: spear_thermal); |
160 | |
161 | /* Disable SPEAr Thermal Sensor */ |
162 | actual_mask = readl_relaxed(stdev->thermal_base); |
163 | writel_relaxed(actual_mask & ~stdev->flags, stdev->thermal_base); |
164 | |
165 | clk_disable(clk: stdev->clk); |
166 | } |
167 | |
168 | static const struct of_device_id spear_thermal_id_table[] = { |
169 | { .compatible = "st,thermal-spear1340" }, |
170 | {} |
171 | }; |
172 | MODULE_DEVICE_TABLE(of, spear_thermal_id_table); |
173 | |
174 | static struct platform_driver spear_thermal_driver = { |
175 | .probe = spear_thermal_probe, |
176 | .remove_new = spear_thermal_exit, |
177 | .driver = { |
178 | .name = "spear_thermal" , |
179 | .pm = &spear_thermal_pm_ops, |
180 | .of_match_table = spear_thermal_id_table, |
181 | }, |
182 | }; |
183 | |
184 | module_platform_driver(spear_thermal_driver); |
185 | |
186 | MODULE_AUTHOR("Vincenzo Frascino <vincenzo.frascino@st.com>" ); |
187 | MODULE_DESCRIPTION("SPEAr thermal driver" ); |
188 | MODULE_LICENSE("GPL" ); |
189 | |