opal-sensor.c

  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * PowerNV sensor code
  4 *
  5 * Copyright (C) 2013 IBM
  6 */
  7
  8#include <linux/delay.h>
  9#include <linux/of.h>
 10#include <linux/of_platform.h>
 11#include <linux/platform_device.h>
 12#include <asm/opal.h>
 13#include <asm/machdep.h>
 14
 15/*
 16 * This will return sensor information to driver based on the requested sensor
 17 * handle. A handle is an opaque id for the powernv, read by the driver from the
 18 * device tree..
 19 */
 20int opal_get_sensor_data(u32 sensor_hndl, u32 *sensor_data)
 21{
 22	int ret, token;
 23	struct opal_msg msg;
 24	__be32 data;
 25
 26	token = opal_async_get_token_interruptible();
 27	if (token < 0)
 28		return token;
 29
 30	ret = opal_sensor_read(sensor_hndl, token, &data);
 31	switch (ret) {
 32	case OPAL_ASYNC_COMPLETION:
 33		ret = opal_async_wait_response(token, &msg);
 34		if (ret) {
 35			pr_err("%s: Failed to wait for the async response, %d\n",
 36			       __func__, ret);
 37			goto out;
 38		}
 39
 40		ret = opal_error_code(opal_get_async_rc(msg));
 41		*sensor_data = be32_to_cpu(data);
 42		break;
 43
 44	case OPAL_SUCCESS:
 45		ret = 0;
 46		*sensor_data = be32_to_cpu(data);
 47		break;
 48
 49	case OPAL_WRONG_STATE:
 50		ret = -EIO;
 51		break;
 52
 53	default:
 54		ret = opal_error_code(ret);
 55		break;
 56	}
 57
 58out:
 59	opal_async_release_token(token);
 60	return ret;
 61}
 62EXPORT_SYMBOL_GPL(opal_get_sensor_data);
 63
 64int opal_get_sensor_data_u64(u32 sensor_hndl, u64 *sensor_data)
 65{
 66	int ret, token;
 67	struct opal_msg msg;
 68	__be64 data;
 69
 70	if (!opal_check_token(OPAL_SENSOR_READ_U64)) {
 71		u32 sdata;
 72
 73		ret = opal_get_sensor_data(sensor_hndl, &sdata);
 74		if (!ret)
 75			*sensor_data = sdata;
 76		return ret;
 77	}
 78
 79	token = opal_async_get_token_interruptible();
 80	if (token < 0)
 81		return token;
 82
 83	ret = opal_sensor_read_u64(sensor_hndl, token, &data);
 84	switch (ret) {
 85	case OPAL_ASYNC_COMPLETION:
 86		ret = opal_async_wait_response(token, &msg);
 87		if (ret) {
 88			pr_err("%s: Failed to wait for the async response, %d\n",
 89			       __func__, ret);
 90			goto out_token;
 91		}
 92
 93		ret = opal_error_code(opal_get_async_rc(msg));
 94		*sensor_data = be64_to_cpu(data);
 95		break;
 96
 97	case OPAL_SUCCESS:
 98		ret = 0;
 99		*sensor_data = be64_to_cpu(data);
100		break;
101
102	case OPAL_WRONG_STATE:
103		ret = -EIO;
104		break;
105
106	default:
107		ret = opal_error_code(ret);
108		break;
109	}
110
111out_token:
112	opal_async_release_token(token);
113	return ret;
114}
115EXPORT_SYMBOL_GPL(opal_get_sensor_data_u64);
116
117int __init opal_sensor_init(void)
118{
119	struct platform_device *pdev;
120	struct device_node *sensor;
121
122	sensor = of_find_node_by_path("/ibm,opal/sensors");
123	if (!sensor) {
124		pr_err("Opal node 'sensors' not found\n");
125		return -ENODEV;
126	}
127
128	pdev = of_platform_device_create(sensor, "opal-sensor", NULL);
129	of_node_put(sensor);
130
131	return PTR_ERR_OR_ZERO(pdev);
132}