1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * PowerNV sensor code
4  *
5  * Copyright (C) 2013 IBM
6  */
7 
8 #include <linux/delay.h>
9 #include <linux/of_platform.h>
10 #include <asm/opal.h>
11 #include <asm/machdep.h>
12 
13 /*
14  * This will return sensor information to driver based on the requested sensor
15  * handle. A handle is an opaque id for the powernv, read by the driver from the
16  * device tree..
17  */
18 int opal_get_sensor_data(u32 sensor_hndl, u32 *sensor_data)
19 {
20 	int ret, token;
21 	struct opal_msg msg;
22 	__be32 data;
23 
24 	token = opal_async_get_token_interruptible();
25 	if (token < 0)
26 		return token;
27 
28 	ret = opal_sensor_read(sensor_hndl, token, &data);
29 	switch (ret) {
30 	case OPAL_ASYNC_COMPLETION:
31 		ret = opal_async_wait_response(token, &msg);
32 		if (ret) {
33 			pr_err("%s: Failed to wait for the async response, %d\n",
34 			       __func__, ret);
35 			goto out;
36 		}
37 
38 		ret = opal_error_code(opal_get_async_rc(msg));
39 		*sensor_data = be32_to_cpu(data);
40 		break;
41 
42 	case OPAL_SUCCESS:
43 		ret = 0;
44 		*sensor_data = be32_to_cpu(data);
45 		break;
46 
47 	case OPAL_WRONG_STATE:
48 		ret = -EIO;
49 		break;
50 
51 	default:
52 		ret = opal_error_code(ret);
53 		break;
54 	}
55 
56 out:
57 	opal_async_release_token(token);
58 	return ret;
59 }
60 EXPORT_SYMBOL_GPL(opal_get_sensor_data);
61 
62 int opal_get_sensor_data_u64(u32 sensor_hndl, u64 *sensor_data)
63 {
64 	int ret, token;
65 	struct opal_msg msg;
66 	__be64 data;
67 
68 	if (!opal_check_token(OPAL_SENSOR_READ_U64)) {
69 		u32 sdata;
70 
71 		ret = opal_get_sensor_data(sensor_hndl, &sdata);
72 		if (!ret)
73 			*sensor_data = sdata;
74 		return ret;
75 	}
76 
77 	token = opal_async_get_token_interruptible();
78 	if (token < 0)
79 		return token;
80 
81 	ret = opal_sensor_read_u64(sensor_hndl, token, &data);
82 	switch (ret) {
83 	case OPAL_ASYNC_COMPLETION:
84 		ret = opal_async_wait_response(token, &msg);
85 		if (ret) {
86 			pr_err("%s: Failed to wait for the async response, %d\n",
87 			       __func__, ret);
88 			goto out_token;
89 		}
90 
91 		ret = opal_error_code(opal_get_async_rc(msg));
92 		*sensor_data = be64_to_cpu(data);
93 		break;
94 
95 	case OPAL_SUCCESS:
96 		ret = 0;
97 		*sensor_data = be64_to_cpu(data);
98 		break;
99 
100 	case OPAL_WRONG_STATE:
101 		ret = -EIO;
102 		break;
103 
104 	default:
105 		ret = opal_error_code(ret);
106 		break;
107 	}
108 
109 out_token:
110 	opal_async_release_token(token);
111 	return ret;
112 }
113 EXPORT_SYMBOL_GPL(opal_get_sensor_data_u64);
114 
115 int __init opal_sensor_init(void)
116 {
117 	struct platform_device *pdev;
118 	struct device_node *sensor;
119 
120 	sensor = of_find_node_by_path("/ibm,opal/sensors");
121 	if (!sensor) {
122 		pr_err("Opal node 'sensors' not found\n");
123 		return -ENODEV;
124 	}
125 
126 	pdev = of_platform_device_create(sensor, "opal-sensor", NULL);
127 	of_node_put(sensor);
128 
129 	return PTR_ERR_OR_ZERO(pdev);
130 }
131