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/platform_device.h>
12 #include <linux/slab.h>
13 #include <linux/thermal.h>
14 
15 #include "thermal_hwmon.h"
16 
17 #define IMX_SC_MISC_FUNC_GET_TEMP	13
18 
19 static struct imx_sc_ipc *thermal_ipc_handle;
20 
21 struct imx_sc_sensor {
22 	struct thermal_zone_device *tzd;
23 	u32 resource_id;
24 };
25 
26 struct req_get_temp {
27 	u16 resource_id;
28 	u8 type;
29 } __packed __aligned(4);
30 
31 struct resp_get_temp {
32 	s16 celsius;
33 	s8 tenths;
34 } __packed __aligned(4);
35 
36 struct imx_sc_msg_misc_get_temp {
37 	struct imx_sc_rpc_msg hdr;
38 	union {
39 		struct req_get_temp req;
40 		struct resp_get_temp resp;
41 	} data;
42 } __packed __aligned(4);
43 
44 static int imx_sc_thermal_get_temp(struct thermal_zone_device *tz, int *temp)
45 {
46 	struct imx_sc_msg_misc_get_temp msg;
47 	struct imx_sc_rpc_msg *hdr = &msg.hdr;
48 	struct imx_sc_sensor *sensor = thermal_zone_device_priv(tz);
49 	int ret;
50 
51 	msg.data.req.resource_id = sensor->resource_id;
52 	msg.data.req.type = IMX_SC_C_TEMP;
53 
54 	hdr->ver = IMX_SC_RPC_VERSION;
55 	hdr->svc = IMX_SC_RPC_SVC_MISC;
56 	hdr->func = IMX_SC_MISC_FUNC_GET_TEMP;
57 	hdr->size = 2;
58 
59 	ret = imx_scu_call_rpc(thermal_ipc_handle, &msg, true);
60 	if (ret)
61 		return ret;
62 
63 	*temp = msg.data.resp.celsius * 1000 + msg.data.resp.tenths * 100;
64 
65 	return 0;
66 }
67 
68 static const struct thermal_zone_device_ops imx_sc_thermal_ops = {
69 	.get_temp = imx_sc_thermal_get_temp,
70 };
71 
72 static int imx_sc_thermal_probe(struct platform_device *pdev)
73 {
74 	struct imx_sc_sensor *sensor;
75 	const int *resource_id;
76 	int i, ret;
77 
78 	ret = imx_scu_get_handle(&thermal_ipc_handle);
79 	if (ret)
80 		return ret;
81 
82 	resource_id = of_device_get_match_data(&pdev->dev);
83 	if (!resource_id)
84 		return -EINVAL;
85 
86 	for (i = 0; resource_id[i] >= 0; i++) {
87 
88 		sensor = devm_kzalloc(&pdev->dev, sizeof(*sensor), GFP_KERNEL);
89 		if (!sensor)
90 			return -ENOMEM;
91 
92 		sensor->resource_id = resource_id[i];
93 
94 		sensor->tzd = devm_thermal_of_zone_register(&pdev->dev, sensor->resource_id,
95 							    sensor, &imx_sc_thermal_ops);
96 		if (IS_ERR(sensor->tzd)) {
97 			/*
98 			 * Save the error value before freeing the
99 			 * sensor pointer, otherwise we endup with a
100 			 * use-after-free error
101 			 */
102 			ret = PTR_ERR(sensor->tzd);
103 
104 			devm_kfree(&pdev->dev, sensor);
105 
106 			/*
107 			 * The thermal framework notifies us there is
108 			 * no thermal zone description for such a
109 			 * sensor id
110 			 */
111 			if (ret == -ENODEV)
112 				continue;
113 
114 			dev_err(&pdev->dev, "failed to register thermal zone\n");
115 			return ret;
116 		}
117 
118 		devm_thermal_add_hwmon_sysfs(&pdev->dev, sensor->tzd);
119 	}
120 
121 	return 0;
122 }
123 
124 static const int imx_sc_sensors[] = {
125 	IMX_SC_R_SYSTEM, IMX_SC_R_PMIC_0,
126 	IMX_SC_R_AP_0, IMX_SC_R_AP_1,
127 	IMX_SC_R_GPU_0_PID0, IMX_SC_R_GPU_1_PID0,
128 	IMX_SC_R_DRC_0, -1 };
129 
130 static const struct of_device_id imx_sc_thermal_table[] = {
131 	{ .compatible = "fsl,imx-sc-thermal", .data =  imx_sc_sensors },
132 	{}
133 };
134 MODULE_DEVICE_TABLE(of, imx_sc_thermal_table);
135 
136 static struct platform_driver imx_sc_thermal_driver = {
137 		.probe = imx_sc_thermal_probe,
138 		.driver = {
139 			.name = "imx-sc-thermal",
140 			.of_match_table = imx_sc_thermal_table,
141 		},
142 };
143 module_platform_driver(imx_sc_thermal_driver);
144 
145 MODULE_AUTHOR("Anson Huang <Anson.Huang@nxp.com>");
146 MODULE_DESCRIPTION("Thermal driver for NXP i.MX SoCs with system controller");
147 MODULE_LICENSE("GPL v2");
148