drivers/base/test/test_async_driver_probe.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2014 Google, Inc.
   4  */
   5
   6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   7
   8 #include <linux/delay.h>
   9 #include <linux/init.h>
  10 #include <linux/hrtimer.h>
  11 #include <linux/module.h>
  12 #include <linux/platform_device.h>
  13 #include <linux/time.h>
  14
  15 #define TEST_PROBE_DELAY        (5 * 1000)      /* 5 sec */
  16 #define TEST_PROBE_THRESHOLD    (TEST_PROBE_DELAY / 2)
  17
  18 static int test_probe(struct platform_device *pdev)
  19 {
  20         dev_info(&pdev->dev, "sleeping for %d msecs in probe\n",
  21                  TEST_PROBE_DELAY);
  22         msleep(TEST_PROBE_DELAY);
  23         dev_info(&pdev->dev, "done sleeping\n");
  24
  25         return 0;
  26 }
  27
  28 static struct platform_driver async_driver = {
  29         .driver = {
  30                 .name = "test_async_driver",
  31                 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
  32         },
  33         .probe = test_probe,
  34 };
  35
  36 static struct platform_driver sync_driver = {
  37         .driver = {
  38                 .name = "test_sync_driver",
  39                 .probe_type = PROBE_FORCE_SYNCHRONOUS,
  40         },
  41         .probe = test_probe,
  42 };
  43
  44 static struct platform_device *async_dev_1, *async_dev_2;
  45 static struct platform_device *sync_dev_1;
  46
  47 static int __init test_async_probe_init(void)
  48 {
  49         ktime_t calltime, delta;
  50         unsigned long long duration;
  51         int error;
  52
  53         pr_info("registering first asynchronous device...\n");
  54
  55         async_dev_1 = platform_device_register_simple("test_async_driver", 1,
  56                                                       NULL, 0);
  57         if (IS_ERR(async_dev_1)) {
  58                 error = PTR_ERR(async_dev_1);
  59                 pr_err("failed to create async_dev_1: %d\n", error);
  60                 return error;
  61         }
  62
  63         pr_info("registering asynchronous driver...\n");
  64         calltime = ktime_get();
  65         error = platform_driver_register(&async_driver);
  66         if (error) {
  67                 pr_err("Failed to register async_driver: %d\n", error);
  68                 goto err_unregister_async_dev_1;
  69         }
  70
  71         delta = ktime_sub(ktime_get(), calltime);
  72         duration = (unsigned long long) ktime_to_ms(delta);
  73         pr_info("registration took %lld msecs\n", duration);
  74         if (duration > TEST_PROBE_THRESHOLD) {
  75                 pr_err("test failed: probe took too long\n");
  76                 error = -ETIMEDOUT;
  77                 goto err_unregister_async_driver;
  78         }
  79
  80         pr_info("registering second asynchronous device...\n");
  81         calltime = ktime_get();
  82         async_dev_2 = platform_device_register_simple("test_async_driver", 2,
  83                                                       NULL, 0);
  84         if (IS_ERR(async_dev_2)) {
  85                 error = PTR_ERR(async_dev_2);
  86                 pr_err("failed to create async_dev_2: %d\n", error);
  87                 goto err_unregister_async_driver;
  88         }
  89
  90         delta = ktime_sub(ktime_get(), calltime);
  91         duration = (unsigned long long) ktime_to_ms(delta);
  92         pr_info("registration took %lld msecs\n", duration);
  93         if (duration > TEST_PROBE_THRESHOLD) {
  94                 pr_err("test failed: probe took too long\n");
  95                 error = -ETIMEDOUT;
  96                 goto err_unregister_async_dev_2;
  97         }
  98
  99         pr_info("registering synchronous driver...\n");
 100
 101         error = platform_driver_register(&sync_driver);
 102         if (error) {
 103                 pr_err("Failed to register async_driver: %d\n", error);
 104                 goto err_unregister_async_dev_2;
 105         }
 106
 107         pr_info("registering synchronous device...\n");
 108         calltime = ktime_get();
 109         sync_dev_1 = platform_device_register_simple("test_sync_driver", 1,
 110                                                      NULL, 0);
 111         if (IS_ERR(sync_dev_1)) {
 112                 error = PTR_ERR(sync_dev_1);
 113                 pr_err("failed to create sync_dev_1: %d\n", error);
 114                 goto err_unregister_sync_driver;
 115         }
 116
 117         delta = ktime_sub(ktime_get(), calltime);
 118         duration = (unsigned long long) ktime_to_ms(delta);
 119         pr_info("registration took %lld msecs\n", duration);
 120         if (duration < TEST_PROBE_THRESHOLD) {
 121                 pr_err("test failed: probe was too quick\n");
 122                 error = -ETIMEDOUT;
 123                 goto err_unregister_sync_dev_1;
 124         }
 125
 126         pr_info("completed successfully");
 127
 128         return 0;
 129
 130 err_unregister_sync_dev_1:
 131         platform_device_unregister(sync_dev_1);
 132
 133 err_unregister_sync_driver:
 134         platform_driver_unregister(&sync_driver);
 135
 136 err_unregister_async_dev_2:
 137         platform_device_unregister(async_dev_2);
 138
 139 err_unregister_async_driver:
 140         platform_driver_unregister(&async_driver);
 141
 142 err_unregister_async_dev_1:
 143         platform_device_unregister(async_dev_1);
 144
 145         return error;
 146 }
 147 module_init(test_async_probe_init);
 148
 149 static void __exit test_async_probe_exit(void)
 150 {
 151         platform_driver_unregister(&async_driver);
 152         platform_driver_unregister(&sync_driver);
 153         platform_device_unregister(async_dev_1);
 154         platform_device_unregister(async_dev_2);
 155         platform_device_unregister(sync_dev_1);
 156 }
 157 module_exit(test_async_probe_exit);
 158
 159 MODULE_DESCRIPTION("Test module for asynchronous driver probing");
 160 MODULE_AUTHOR("Dmitry Torokhov <dtor@chromium.org>");
 161 MODULE_LICENSE("GPL");