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_hwmon.h"
17 
18 #define IMX_SC_MISC_FUNC_GET_TEMP	13
19 
20 static struct imx_sc_ipc *thermal_ipc_handle;
21 
22 struct imx_sc_sensor {
23 	struct thermal_zone_device *tzd;
24 	u32 resource_id;
25 };
26 
27 struct req_get_temp {
28 	u16 resource_id;
29 	u8 type;
30 } __packed __aligned(4);
31 
32 struct resp_get_temp {
33 	s16 celsius;
34 	s8 tenths;
35 } __packed __aligned(4);
36 
37 struct imx_sc_msg_misc_get_temp {
38 	struct imx_sc_rpc_msg hdr;
39 	union {
40 		struct req_get_temp req;
41 		struct resp_get_temp resp;
42 	} data;
43 } __packed __aligned(4);
44 
45 static int imx_sc_thermal_get_temp(struct thermal_zone_device *tz, int *temp)
46 {
47 	struct imx_sc_msg_misc_get_temp msg;
48 	struct imx_sc_rpc_msg *hdr = &msg.hdr;
49 	struct imx_sc_sensor *sensor = tz->devdata;
50 	int ret;
51 
52 	msg.data.req.resource_id = sensor->resource_id;
53 	msg.data.req.type = IMX_SC_C_TEMP;
54 
55 	hdr->ver = IMX_SC_RPC_VERSION;
56 	hdr->svc = IMX_SC_RPC_SVC_MISC;
57 	hdr->func = IMX_SC_MISC_FUNC_GET_TEMP;
58 	hdr->size = 2;
59 
60 	ret = imx_scu_call_rpc(thermal_ipc_handle, &msg, true);
61 	if (ret) {
62 		dev_err(&sensor->tzd->device, "read temp sensor %d failed, ret %d\n",
63 			sensor->resource_id, ret);
64 		return ret;
65 	}
66 
67 	*temp = msg.data.resp.celsius * 1000 + msg.data.resp.tenths * 100;
68 
69 	return 0;
70 }
71 
72 static const struct thermal_zone_device_ops imx_sc_thermal_ops = {
73 	.get_temp = imx_sc_thermal_get_temp,
74 };
75 
76 static int imx_sc_thermal_probe(struct platform_device *pdev)
77 {
78 	struct imx_sc_sensor *sensor;
79 	const int *resource_id;
80 	int i, ret;
81 
82 	ret = imx_scu_get_handle(&thermal_ipc_handle);
83 	if (ret)
84 		return ret;
85 
86 	resource_id = of_device_get_match_data(&pdev->dev);
87 	if (!resource_id)
88 		return -EINVAL;
89 
90 	for (i = 0; resource_id[i] >= 0; i++) {
91 
92 		sensor = devm_kzalloc(&pdev->dev, sizeof(*sensor), GFP_KERNEL);
93 		if (!sensor)
94 			return -ENOMEM;
95 
96 		sensor->resource_id = resource_id[i];
97 
98 		sensor->tzd = devm_thermal_of_zone_register(&pdev->dev, sensor->resource_id,
99 							    sensor, &imx_sc_thermal_ops);
100 		if (IS_ERR(sensor->tzd)) {
101 			/*
102 			 * Save the error value before freeing the
103 			 * sensor pointer, otherwise we endup with a
104 			 * use-after-free error
105 			 */
106 			ret = PTR_ERR(sensor->tzd);
107 
108 			devm_kfree(&pdev->dev, sensor);
109 
110 			/*
111 			 * The thermal framework notifies us there is
112 			 * no thermal zone description for such a
113 			 * sensor id
114 			 */
115 			if (ret == -ENODEV)
116 				continue;
117 
118 			dev_err(&pdev->dev, "failed to register thermal zone\n");
119 			return ret;
120 		}
121 
122 		if (devm_thermal_add_hwmon_sysfs(sensor->tzd))
123 			dev_warn(&pdev->dev, "failed to add hwmon sysfs attributes\n");
124 	}
125 
126 	return 0;
127 }
128 
129 static const int imx_sc_sensors[] = {
130 	IMX_SC_R_SYSTEM, IMX_SC_R_PMIC_0,
131 	IMX_SC_R_AP_0, IMX_SC_R_AP_1,
132 	IMX_SC_R_GPU_0_PID0, IMX_SC_R_GPU_1_PID0,
133 	IMX_SC_R_DRC_0, -1 };
134 
135 static const struct of_device_id imx_sc_thermal_table[] = {
136 	{ .compatible = "fsl,imx-sc-thermal", .data =  imx_sc_sensors },
137 	{}
138 };
139 MODULE_DEVICE_TABLE(of, imx_sc_thermal_table);
140 
141 static struct platform_driver imx_sc_thermal_driver = {
142 		.probe = imx_sc_thermal_probe,
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