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// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2014 Google, Inc.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/hrtimer.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/time.h>
#define TEST_PROBE_DELAY (5 * 1000) /* 5 sec */
#define TEST_PROBE_THRESHOLD (TEST_PROBE_DELAY / 2)
static int test_probe(struct platform_device *pdev)
{
dev_info(&pdev->dev, "sleeping for %d msecs in probe\n",
TEST_PROBE_DELAY);
msleep(TEST_PROBE_DELAY);
dev_info(&pdev->dev, "done sleeping\n");
return 0;
}
static struct platform_driver async_driver = {
.driver = {
.name = "test_async_driver",
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
},
.probe = test_probe,
};
static struct platform_driver sync_driver = {
.driver = {
.name = "test_sync_driver",
.probe_type = PROBE_FORCE_SYNCHRONOUS,
},
.probe = test_probe,
};
static struct platform_device *async_dev_1, *async_dev_2;
static struct platform_device *sync_dev_1;
static int __init test_async_probe_init(void)
{
ktime_t calltime, delta;
unsigned long long duration;
int error;
pr_info("registering first asynchronous device...\n");
async_dev_1 = platform_device_register_simple("test_async_driver", 1,
NULL, 0);
if (IS_ERR(async_dev_1)) {
error = PTR_ERR(async_dev_1);
pr_err("failed to create async_dev_1: %d\n", error);
return error;
}
pr_info("registering asynchronous driver...\n");
calltime = ktime_get();
error = platform_driver_register(&async_driver);
if (error) {
pr_err("Failed to register async_driver: %d\n", error);
goto err_unregister_async_dev_1;
}
delta = ktime_sub(ktime_get(), calltime);
duration = (unsigned long long) ktime_to_ms(delta);
pr_info("registration took %lld msecs\n", duration);
if (duration > TEST_PROBE_THRESHOLD) {
pr_err("test failed: probe took too long\n");
error = -ETIMEDOUT;
goto err_unregister_async_driver;
}
pr_info("registering second asynchronous device...\n");
calltime = ktime_get();
async_dev_2 = platform_device_register_simple("test_async_driver", 2,
NULL, 0);
if (IS_ERR(async_dev_2)) {
error = PTR_ERR(async_dev_2);
pr_err("failed to create async_dev_2: %d\n", error);
goto err_unregister_async_driver;
}
delta = ktime_sub(ktime_get(), calltime);
duration = (unsigned long long) ktime_to_ms(delta);
pr_info("registration took %lld msecs\n", duration);
if (duration > TEST_PROBE_THRESHOLD) {
pr_err("test failed: probe took too long\n");
error = -ETIMEDOUT;
goto err_unregister_async_dev_2;
}
pr_info("registering synchronous driver...\n");
error = platform_driver_register(&sync_driver);
if (error) {
pr_err("Failed to register async_driver: %d\n", error);
goto err_unregister_async_dev_2;
}
pr_info("registering synchronous device...\n");
calltime = ktime_get();
sync_dev_1 = platform_device_register_simple("test_sync_driver", 1,
NULL, 0);
if (IS_ERR(sync_dev_1)) {
error = PTR_ERR(sync_dev_1);
pr_err("failed to create sync_dev_1: %d\n", error);
goto err_unregister_sync_driver;
}
delta = ktime_sub(ktime_get(), calltime);
duration = (unsigned long long) ktime_to_ms(delta);
pr_info("registration took %lld msecs\n", duration);
if (duration < TEST_PROBE_THRESHOLD) {
pr_err("test failed: probe was too quick\n");
error = -ETIMEDOUT;
goto err_unregister_sync_dev_1;
}
pr_info("completed successfully");
return 0;
err_unregister_sync_dev_1:
platform_device_unregister(sync_dev_1);
err_unregister_sync_driver:
platform_driver_unregister(&sync_driver);
err_unregister_async_dev_2:
platform_device_unregister(async_dev_2);
err_unregister_async_driver:
platform_driver_unregister(&async_driver);
err_unregister_async_dev_1:
platform_device_unregister(async_dev_1);
return error;
}
module_init(test_async_probe_init);
static void __exit test_async_probe_exit(void)
{
platform_driver_unregister(&async_driver);
platform_driver_unregister(&sync_driver);
platform_device_unregister(async_dev_1);
platform_device_unregister(async_dev_2);
platform_device_unregister(sync_dev_1);
}
module_exit(test_async_probe_exit);
MODULE_DESCRIPTION("Test module for asynchronous driver probing");
MODULE_AUTHOR("Dmitry Torokhov <dtor@chromium.org>");
MODULE_LICENSE("GPL");
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