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.h>
10 #include <linux/of_platform.h>
11 #include <linux/platform_device.h>
12 #include <asm/opal.h>
13 #include <asm/machdep.h>
14 
15 /*
16  * This will return sensor information to driver based on the requested sensor
17  * handle. A handle is an opaque id for the powernv, read by the driver from the
18  * device tree..
19  */
20 int opal_get_sensor_data(u32 sensor_hndl, u32 *sensor_data)
21 {
22 	int ret, token;
23 	struct opal_msg msg;
24 	__be32 data;
25 
26 	token = opal_async_get_token_interruptible();
27 	if (token < 0)
28 		return token;
29 
30 	ret = opal_sensor_read(sensor_hndl, token, &data);
31 	switch (ret) {
32 	case OPAL_ASYNC_COMPLETION:
33 		ret = opal_async_wait_response(token, &msg);
34 		if (ret) {
35 			pr_err("%s: Failed to wait for the async response, %d\n",
36 			       __func__, ret);
37 			goto out;
38 		}
39 
40 		ret = opal_error_code(opal_get_async_rc(msg));
41 		*sensor_data = be32_to_cpu(data);
42 		break;
43 
44 	case OPAL_SUCCESS:
45 		ret = 0;
46 		*sensor_data = be32_to_cpu(data);
47 		break;
48 
49 	case OPAL_WRONG_STATE:
50 		ret = -EIO;
51 		break;
52 
53 	default:
54 		ret = opal_error_code(ret);
55 		break;
56 	}
57 
58 out:
59 	opal_async_release_token(token);
60 	return ret;
61 }
62 EXPORT_SYMBOL_GPL(opal_get_sensor_data);
63 
64 int opal_get_sensor_data_u64(u32 sensor_hndl, u64 *sensor_data)
65 {
66 	int ret, token;
67 	struct opal_msg msg;
68 	__be64 data;
69 
70 	if (!opal_check_token(OPAL_SENSOR_READ_U64)) {
71 		u32 sdata;
72 
73 		ret = opal_get_sensor_data(sensor_hndl, &sdata);
74 		if (!ret)
75 			*sensor_data = sdata;
76 		return ret;
77 	}
78 
79 	token = opal_async_get_token_interruptible();
80 	if (token < 0)
81 		return token;
82 
83 	ret = opal_sensor_read_u64(sensor_hndl, token, &data);
84 	switch (ret) {
85 	case OPAL_ASYNC_COMPLETION:
86 		ret = opal_async_wait_response(token, &msg);
87 		if (ret) {
88 			pr_err("%s: Failed to wait for the async response, %d\n",
89 			       __func__, ret);
90 			goto out_token;
91 		}
92 
93 		ret = opal_error_code(opal_get_async_rc(msg));
94 		*sensor_data = be64_to_cpu(data);
95 		break;
96 
97 	case OPAL_SUCCESS:
98 		ret = 0;
99 		*sensor_data = be64_to_cpu(data);
100 		break;
101 
102 	case OPAL_WRONG_STATE:
103 		ret = -EIO;
104 		break;
105 
106 	default:
107 		ret = opal_error_code(ret);
108 		break;
109 	}
110 
111 out_token:
112 	opal_async_release_token(token);
113 	return ret;
114 }
115 EXPORT_SYMBOL_GPL(opal_get_sensor_data_u64);
116 
117 int __init opal_sensor_init(void)
118 {
119 	struct platform_device *pdev;
120 	struct device_node *sensor;
121 
122 	sensor = of_find_node_by_path("/ibm,opal/sensors");
123 	if (!sensor) {
124 		pr_err("Opal node 'sensors' not found\n");
125 		return -ENODEV;
126 	}
127 
128 	pdev = of_platform_device_create(sensor, "opal-sensor", NULL);
129 	of_node_put(sensor);
130 
131 	return PTR_ERR_OR_ZERO(pdev);
132 }
133