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 = thermal_zone_device_priv(tz);
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 		return ret;
63 
64 	*temp = msg.data.resp.celsius * 1000 + msg.data.resp.tenths * 100;
65 
66 	return 0;
67 }
68 
69 static const struct thermal_zone_device_ops imx_sc_thermal_ops = {
70 	.get_temp = imx_sc_thermal_get_temp,
71 };
72 
73 static int imx_sc_thermal_probe(struct platform_device *pdev)
74 {
75 	struct imx_sc_sensor *sensor;
76 	const int *resource_id;
77 	int i, ret;
78 
79 	ret = imx_scu_get_handle(&thermal_ipc_handle);
80 	if (ret)
81 		return ret;
82 
83 	resource_id = of_device_get_match_data(&pdev->dev);
84 	if (!resource_id)
85 		return -EINVAL;
86 
87 	for (i = 0; resource_id[i] >= 0; i++) {
88 
89 		sensor = devm_kzalloc(&pdev->dev, sizeof(*sensor), GFP_KERNEL);
90 		if (!sensor)
91 			return -ENOMEM;
92 
93 		sensor->resource_id = resource_id[i];
94 
95 		sensor->tzd = devm_thermal_of_zone_register(&pdev->dev, sensor->resource_id,
96 							    sensor, &imx_sc_thermal_ops);
97 		if (IS_ERR(sensor->tzd)) {
98 			/*
99 			 * Save the error value before freeing the
100 			 * sensor pointer, otherwise we endup with a
101 			 * use-after-free error
102 			 */
103 			ret = PTR_ERR(sensor->tzd);
104 
105 			devm_kfree(&pdev->dev, sensor);
106 
107 			/*
108 			 * The thermal framework notifies us there is
109 			 * no thermal zone description for such a
110 			 * sensor id
111 			 */
112 			if (ret == -ENODEV)
113 				continue;
114 
115 			dev_err(&pdev->dev, "failed to register thermal zone\n");
116 			return ret;
117 		}
118 
119 		if (devm_thermal_add_hwmon_sysfs(&pdev->dev, sensor->tzd))
120 			dev_warn(&pdev->dev, "failed to add hwmon sysfs attributes\n");
121 	}
122 
123 	return 0;
124 }
125 
126 static const int imx_sc_sensors[] = {
127 	IMX_SC_R_SYSTEM, IMX_SC_R_PMIC_0,
128 	IMX_SC_R_AP_0, IMX_SC_R_AP_1,
129 	IMX_SC_R_GPU_0_PID0, IMX_SC_R_GPU_1_PID0,
130 	IMX_SC_R_DRC_0, -1 };
131 
132 static const struct of_device_id imx_sc_thermal_table[] = {
133 	{ .compatible = "fsl,imx-sc-thermal", .data =  imx_sc_sensors },
134 	{}
135 };
136 MODULE_DEVICE_TABLE(of, imx_sc_thermal_table);
137 
138 static struct platform_driver imx_sc_thermal_driver = {
139 		.probe = imx_sc_thermal_probe,
140 		.driver = {
141 			.name = "imx-sc-thermal",
142 			.of_match_table = imx_sc_thermal_table,
143 		},
144 };
145 module_platform_driver(imx_sc_thermal_driver);
146 
147 MODULE_AUTHOR("Anson Huang <Anson.Huang@nxp.com>");
148 MODULE_DESCRIPTION("Thermal driver for NXP i.MX SoCs with system controller");
149 MODULE_LICENSE("GPL v2");
150