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(struct thermal_zone_device *tz, 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 = tz->devdata;
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_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 imx_sc_sensor *sensor;
80 	const int *resource_id;
81 	int i, ret;
82 
83 	ret = imx_scu_get_handle(&thermal_ipc_handle);
84 	if (ret)
85 		return ret;
86 
87 	resource_id = of_device_get_match_data(&pdev->dev);
88 	if (!resource_id)
89 		return -EINVAL;
90 
91 	for (i = 0; resource_id[i] > 0; i++) {
92 
93 		sensor = devm_kzalloc(&pdev->dev, sizeof(*sensor), GFP_KERNEL);
94 		if (!sensor)
95 			return -ENOMEM;
96 
97 		sensor->resource_id = resource_id[i];
98 
99 		sensor->tzd = devm_thermal_of_zone_register(&pdev->dev, sensor->resource_id,
100 							    sensor, &imx_sc_thermal_ops);
101 		if (IS_ERR(sensor->tzd)) {
102 			/*
103 			 * Save the error value before freeing the
104 			 * sensor pointer, otherwise we endup with a
105 			 * use-after-free error
106 			 */
107 			ret = PTR_ERR(sensor->tzd);
108 
109 			devm_kfree(&pdev->dev, sensor);
110 
111 			/*
112 			 * The thermal framework notifies us there is
113 			 * no thermal zone description for such a
114 			 * sensor id
115 			 */
116 			if (ret == -ENODEV)
117 				continue;
118 
119 			dev_err(&pdev->dev, "failed to register thermal zone\n");
120 			return ret;
121 		}
122 
123 		if (devm_thermal_add_hwmon_sysfs(sensor->tzd))
124 			dev_warn(&pdev->dev, "failed to add hwmon sysfs attributes\n");
125 	}
126 
127 	return 0;
128 }
129 
130 static int imx_sc_thermal_remove(struct platform_device *pdev)
131 {
132 	return 0;
133 }
134 
135 static int imx_sc_sensors[] = { IMX_SC_R_SYSTEM, IMX_SC_R_PMIC_0, -1 };
136 
137 static const struct of_device_id imx_sc_thermal_table[] = {
138 	{ .compatible = "fsl,imx-sc-thermal", .data =  imx_sc_sensors },
139 	{}
140 };
141 MODULE_DEVICE_TABLE(of, imx_sc_thermal_table);
142 
143 static struct platform_driver imx_sc_thermal_driver = {
144 		.probe = imx_sc_thermal_probe,
145 		.remove	= imx_sc_thermal_remove,
146 		.driver = {
147 			.name = "imx-sc-thermal",
148 			.of_match_table = imx_sc_thermal_table,
149 		},
150 };
151 module_platform_driver(imx_sc_thermal_driver);
152 
153 MODULE_AUTHOR("Anson Huang <Anson.Huang@nxp.com>");
154 MODULE_DESCRIPTION("Thermal driver for NXP i.MX SoCs with system controller");
155 MODULE_LICENSE("GPL v2");
156