1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright 2018-2020 NXP.
4  */
5 
6 #include <dt-bindings/firmware/imx/rsrc.h>
7 #include <linux/err.h>
8 #include <linux/firmware/imx/sci.h>
9 #include <linux/module.h>
10 #include <linux/of.h>
11 #include <linux/of_device.h>
12 #include <linux/platform_device.h>
13 #include <linux/slab.h>
14 #include <linux/thermal.h>
15 
16 #include "thermal_core.h"
17 #include "thermal_hwmon.h"
18 
19 #define IMX_SC_MISC_FUNC_GET_TEMP	13
20 
21 static struct imx_sc_ipc *thermal_ipc_handle;
22 
23 struct imx_sc_sensor {
24 	struct thermal_zone_device *tzd;
25 	u32 resource_id;
26 };
27 
28 struct req_get_temp {
29 	u16 resource_id;
30 	u8 type;
31 } __packed __aligned(4);
32 
33 struct resp_get_temp {
34 	s16 celsius;
35 	s8 tenths;
36 } __packed __aligned(4);
37 
38 struct imx_sc_msg_misc_get_temp {
39 	struct imx_sc_rpc_msg hdr;
40 	union {
41 		struct req_get_temp req;
42 		struct resp_get_temp resp;
43 	} data;
44 } __packed __aligned(4);
45 
46 static int imx_sc_thermal_get_temp(void *data, int *temp)
47 {
48 	struct imx_sc_msg_misc_get_temp msg;
49 	struct imx_sc_rpc_msg *hdr = &msg.hdr;
50 	struct imx_sc_sensor *sensor = data;
51 	int ret;
52 
53 	msg.data.req.resource_id = sensor->resource_id;
54 	msg.data.req.type = IMX_SC_C_TEMP;
55 
56 	hdr->ver = IMX_SC_RPC_VERSION;
57 	hdr->svc = IMX_SC_RPC_SVC_MISC;
58 	hdr->func = IMX_SC_MISC_FUNC_GET_TEMP;
59 	hdr->size = 2;
60 
61 	ret = imx_scu_call_rpc(thermal_ipc_handle, &msg, true);
62 	if (ret) {
63 		dev_err(&sensor->tzd->device, "read temp sensor %d failed, ret %d\n",
64 			sensor->resource_id, ret);
65 		return ret;
66 	}
67 
68 	*temp = msg.data.resp.celsius * 1000 + msg.data.resp.tenths * 100;
69 
70 	return 0;
71 }
72 
73 static const struct thermal_zone_of_device_ops imx_sc_thermal_ops = {
74 	.get_temp = imx_sc_thermal_get_temp,
75 };
76 
77 static int imx_sc_thermal_probe(struct platform_device *pdev)
78 {
79 	struct device_node *np, *child, *sensor_np;
80 	struct imx_sc_sensor *sensor;
81 	int ret;
82 
83 	ret = imx_scu_get_handle(&thermal_ipc_handle);
84 	if (ret)
85 		return ret;
86 
87 	np = of_find_node_by_name(NULL, "thermal-zones");
88 	if (!np)
89 		return -ENODEV;
90 
91 	sensor_np = of_node_get(pdev->dev.of_node);
92 
93 	for_each_available_child_of_node(np, child) {
94 		sensor = devm_kzalloc(&pdev->dev, sizeof(*sensor), GFP_KERNEL);
95 		if (!sensor) {
96 			of_node_put(sensor_np);
97 			return -ENOMEM;
98 		}
99 
100 		ret = thermal_zone_of_get_sensor_id(child,
101 						    sensor_np,
102 						    &sensor->resource_id);
103 		if (ret < 0) {
104 			dev_err(&pdev->dev,
105 				"failed to get valid sensor resource id: %d\n",
106 				ret);
107 			break;
108 		}
109 
110 		sensor->tzd = devm_thermal_zone_of_sensor_register(&pdev->dev,
111 								   sensor->resource_id,
112 								   sensor,
113 								   &imx_sc_thermal_ops);
114 		if (IS_ERR(sensor->tzd)) {
115 			dev_err(&pdev->dev, "failed to register thermal zone\n");
116 			ret = PTR_ERR(sensor->tzd);
117 			break;
118 		}
119 
120 		if (devm_thermal_add_hwmon_sysfs(sensor->tzd))
121 			dev_warn(&pdev->dev, "failed to add hwmon sysfs attributes\n");
122 	}
123 
124 	of_node_put(sensor_np);
125 
126 	return ret;
127 }
128 
129 static int imx_sc_thermal_remove(struct platform_device *pdev)
130 {
131 	return 0;
132 }
133 
134 static const struct of_device_id imx_sc_thermal_table[] = {
135 	{ .compatible = "fsl,imx-sc-thermal", },
136 	{}
137 };
138 MODULE_DEVICE_TABLE(of, imx_sc_thermal_table);
139 
140 static struct platform_driver imx_sc_thermal_driver = {
141 		.probe = imx_sc_thermal_probe,
142 		.remove	= imx_sc_thermal_remove,
143 		.driver = {
144 			.name = "imx-sc-thermal",
145 			.of_match_table = imx_sc_thermal_table,
146 		},
147 };
148 module_platform_driver(imx_sc_thermal_driver);
149 
150 MODULE_AUTHOR("Anson Huang <Anson.Huang@nxp.com>");
151 MODULE_DESCRIPTION("Thermal driver for NXP i.MX SoCs with system controller");
152 MODULE_LICENSE("GPL v2");
153