LXR linux/arch/powerpc/platforms/powernv/opal-sensor.c

   1/*
   2 * PowerNV sensor code
   3 *
   4 * Copyright (C) 2013 IBM
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation; either version 2 of the License, or
   9 * (at your option) any later version.
  10 *
  11 * This program is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU General Public License
  17 * along with this program; if not, write to the Free Software
  18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19 */
  20
  21#include <linux/delay.h>
  22#include <linux/of_platform.h>
  23#include <asm/opal.h>
  24#include <asm/machdep.h>
  25
  26/*
  27 * This will return sensor information to driver based on the requested sensor
  28 * handle. A handle is an opaque id for the powernv, read by the driver from the
  29 * device tree..
  30 */
  31int opal_get_sensor_data(u32 sensor_hndl, u32 *sensor_data)
  32{
  33        int ret, token;
  34        struct opal_msg msg;
  35        __be32 data;
  36
  37        token = opal_async_get_token_interruptible();
  38        if (token < 0)
  39                return token;
  40
  41        ret = opal_sensor_read(sensor_hndl, token, &data);
  42        switch (ret) {
  43        case OPAL_ASYNC_COMPLETION:
  44                ret = opal_async_wait_response(token, &msg);
  45                if (ret) {
  46                        pr_err("%s: Failed to wait for the async response, %d\n",
  47                               __func__, ret);
  48                        goto out;
  49                }
  50
  51                ret = opal_error_code(opal_get_async_rc(msg));
  52                *sensor_data = be32_to_cpu(data);
  53                break;
  54
  55        case OPAL_SUCCESS:
  56                ret = 0;
  57                *sensor_data = be32_to_cpu(data);
  58                break;
  59
  60        case OPAL_WRONG_STATE:
  61                ret = -EIO;
  62                break;
  63
  64        default:
  65                ret = opal_error_code(ret);
  66                break;
  67        }
  68
  69out:
  70        opal_async_release_token(token);
  71        return ret;
  72}
  73EXPORT_SYMBOL_GPL(opal_get_sensor_data);
  74
  75int opal_get_sensor_data_u64(u32 sensor_hndl, u64 *sensor_data)
  76{
  77        int ret, token;
  78        struct opal_msg msg;
  79        __be64 data;
  80
  81        if (!opal_check_token(OPAL_SENSOR_READ_U64)) {
  82                u32 sdata;
  83
  84                ret = opal_get_sensor_data(sensor_hndl, &sdata);
  85                if (!ret)
  86                        *sensor_data = sdata;
  87                return ret;
  88        }
  89
  90        token = opal_async_get_token_interruptible();
  91        if (token < 0)
  92                return token;
  93
  94        ret = opal_sensor_read_u64(sensor_hndl, token, &data);
  95        switch (ret) {
  96        case OPAL_ASYNC_COMPLETION:
  97                ret = opal_async_wait_response(token, &msg);
  98                if (ret) {
  99                        pr_err("%s: Failed to wait for the async response, %d\n",
 100                               __func__, ret);
 101                        goto out_token;
 102                }
 103
 104                ret = opal_error_code(opal_get_async_rc(msg));
 105                *sensor_data = be64_to_cpu(data);
 106                break;
 107
 108        case OPAL_SUCCESS:
 109                ret = 0;
 110                *sensor_data = be64_to_cpu(data);
 111                break;
 112
 113        case OPAL_WRONG_STATE:
 114                ret = -EIO;
 115                break;
 116
 117        default:
 118                ret = opal_error_code(ret);
 119                break;
 120        }
 121
 122out_token:
 123        opal_async_release_token(token);
 124        return ret;
 125}
 126EXPORT_SYMBOL_GPL(opal_get_sensor_data_u64);
 127
 128int __init opal_sensor_init(void)
 129{
 130        struct platform_device *pdev;
 131        struct device_node *sensor;
 132
 133        sensor = of_find_node_by_path("/ibm,opal/sensors");
 134        if (!sensor) {
 135                pr_err("Opal node 'sensors' not found\n");
 136                return -ENODEV;
 137        }
 138
 139        pdev = of_platform_device_create(sensor, "opal-sensor", NULL);
 140        of_node_put(sensor);
 141
 142        return PTR_ERR_OR_ZERO(pdev);
 143}
 144