platforms/powernv/opal-sensor.c

0001 // SPDX-License-Identifier: GPL-2.0-or-later
0002 /*
0003  * PowerNV sensor code
0004  *
0005  * Copyright (C) 2013 IBM
0006  */
0007
0008 #include <linux/delay.h>
0009 #include <linux/of_platform.h>
0010 #include <asm/opal.h>
0011 #include <asm/machdep.h>
0012
0013 /*
0014  * This will return sensor information to driver based on the requested sensor
0015  * handle. A handle is an opaque id for the powernv, read by the driver from the
0016  * device tree..
0017  */
0018 int opal_get_sensor_data(u32 sensor_hndl, u32 *sensor_data)
0019 {
0020     int ret, token;
0021     struct opal_msg msg;
0022     __be32 data;
0023
0024     token = opal_async_get_token_interruptible();
0025     if (token < 0)
0026         return token;
0027
0028     ret = opal_sensor_read(sensor_hndl, token, &data);
0029     switch (ret) {
0030     case OPAL_ASYNC_COMPLETION:
0031         ret = opal_async_wait_response(token, &msg);
0032         if (ret) {
0033             pr_err("%s: Failed to wait for the async response, %d\n",
0034                    __func__, ret);
0035             goto out;
0036         }
0037
0038         ret = opal_error_code(opal_get_async_rc(msg));
0039         *sensor_data = be32_to_cpu(data);
0040         break;
0041
0042     case OPAL_SUCCESS:
0043         ret = 0;
0044         *sensor_data = be32_to_cpu(data);
0045         break;
0046
0047     case OPAL_WRONG_STATE:
0048         ret = -EIO;
0049         break;
0050
0051     default:
0052         ret = opal_error_code(ret);
0053         break;
0054     }
0055
0056 out:
0057     opal_async_release_token(token);
0058     return ret;
0059 }
0060 EXPORT_SYMBOL_GPL(opal_get_sensor_data);
0061
0062 int opal_get_sensor_data_u64(u32 sensor_hndl, u64 *sensor_data)
0063 {
0064     int ret, token;
0065     struct opal_msg msg;
0066     __be64 data;
0067
0068     if (!opal_check_token(OPAL_SENSOR_READ_U64)) {
0069         u32 sdata;
0070
0071         ret = opal_get_sensor_data(sensor_hndl, &sdata);
0072         if (!ret)
0073             *sensor_data = sdata;
0074         return ret;
0075     }
0076
0077     token = opal_async_get_token_interruptible();
0078     if (token < 0)
0079         return token;
0080
0081     ret = opal_sensor_read_u64(sensor_hndl, token, &data);
0082     switch (ret) {
0083     case OPAL_ASYNC_COMPLETION:
0084         ret = opal_async_wait_response(token, &msg);
0085         if (ret) {
0086             pr_err("%s: Failed to wait for the async response, %d\n",
0087                    __func__, ret);
0088             goto out_token;
0089         }
0090
0091         ret = opal_error_code(opal_get_async_rc(msg));
0092         *sensor_data = be64_to_cpu(data);
0093         break;
0094
0095     case OPAL_SUCCESS:
0096         ret = 0;
0097         *sensor_data = be64_to_cpu(data);
0098         break;
0099
0100     case OPAL_WRONG_STATE:
0101         ret = -EIO;
0102         break;
0103
0104     default:
0105         ret = opal_error_code(ret);
0106         break;
0107     }
0108
0109 out_token:
0110     opal_async_release_token(token);
0111     return ret;
0112 }
0113 EXPORT_SYMBOL_GPL(opal_get_sensor_data_u64);
0114
0115 int __init opal_sensor_init(void)
0116 {
0117     struct platform_device *pdev;
0118     struct device_node *sensor;
0119
0120     sensor = of_find_node_by_path("/ibm,opal/sensors");
0121     if (!sensor) {
0122         pr_err("Opal node 'sensors' not found\n");
0123         return -ENODEV;
0124     }
0125
0126     pdev = of_platform_device_create(sensor, "opal-sensor", NULL);
0127     of_node_put(sensor);
0128
0129     return PTR_ERR_OR_ZERO(pdev);
0130 }