linux/drivers/thermal/imx_sc_thermal.c
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   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
  21static struct imx_sc_ipc *thermal_ipc_handle;
  22
  23struct imx_sc_sensor {
  24        struct thermal_zone_device *tzd;
  25        u32 resource_id;
  26};
  27
  28struct req_get_temp {
  29        u16 resource_id;
  30        u8 type;
  31} __packed __aligned(4);
  32
  33struct resp_get_temp {
  34        s16 celsius;
  35        s8 tenths;
  36} __packed __aligned(4);
  37
  38struct 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
  46static 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
  73static const struct thermal_zone_of_device_ops imx_sc_thermal_ops = {
  74        .get_temp = imx_sc_thermal_get_temp,
  75};
  76
  77static 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(child);
  97                        of_node_put(sensor_np);
  98                        return -ENOMEM;
  99                }
 100
 101                ret = thermal_zone_of_get_sensor_id(child,
 102                                                    sensor_np,
 103                                                    &sensor->resource_id);
 104                if (ret < 0) {
 105                        dev_err(&pdev->dev,
 106                                "failed to get valid sensor resource id: %d\n",
 107                                ret);
 108                        of_node_put(child);
 109                        break;
 110                }
 111
 112                sensor->tzd = devm_thermal_zone_of_sensor_register(&pdev->dev,
 113                                                                   sensor->resource_id,
 114                                                                   sensor,
 115                                                                   &imx_sc_thermal_ops);
 116                if (IS_ERR(sensor->tzd)) {
 117                        dev_err(&pdev->dev, "failed to register thermal zone\n");
 118                        ret = PTR_ERR(sensor->tzd);
 119                        of_node_put(child);
 120                        break;
 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        of_node_put(sensor_np);
 128
 129        return ret;
 130}
 131
 132static int imx_sc_thermal_remove(struct platform_device *pdev)
 133{
 134        return 0;
 135}
 136
 137static const struct of_device_id imx_sc_thermal_table[] = {
 138        { .compatible = "fsl,imx-sc-thermal", },
 139        {}
 140};
 141MODULE_DEVICE_TABLE(of, imx_sc_thermal_table);
 142
 143static 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};
 151module_platform_driver(imx_sc_thermal_driver);
 152
 153MODULE_AUTHOR("Anson Huang <Anson.Huang@nxp.com>");
 154MODULE_DESCRIPTION("Thermal driver for NXP i.MX SoCs with system controller");
 155MODULE_LICENSE("GPL v2");
 156