kernel_optimize_test/drivers/thermal/db8500_cpufreq_cooling.c
Eduardo Valentin 0f1be51c35 thermal: cpu_cooling: check for the readiness of cpufreq layer
In this patch, the cpu_cooling code checks for the usability of cpufreq
layer before proceeding with the CPU cooling device registration. The
main reason is: CPU cooling device is not usable if cpufreq cannot
switch frequencies.

Similar checks are spread in thermal drivers. Thus, the advantage now
is to have the check in a single place: cpu cooling device registration.
For this reason, this patch also updates the existing drivers that
depend on CPU cooling to simply propagate the error code of the cpu
cooling registration call. Therefore, in case cpufreq is not ready, the
thermal drivers will still return -EPROBE_DEFER, in an attempt to try
again when cpufreq layer gets ready.

Cc: devicetree@vger.kernel.org
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Zhang Rui <rui.zhang@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
2014-12-08 12:08:53 -04:00

103 lines
2.7 KiB
C

/*
* db8500_cpufreq_cooling.c - DB8500 cpufreq works as cooling device.
*
* Copyright (C) 2012 ST-Ericsson
* Copyright (C) 2012 Linaro Ltd.
*
* Author: Hongbo Zhang <hongbo.zhang@linaro.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/cpu_cooling.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
static int db8500_cpufreq_cooling_probe(struct platform_device *pdev)
{
struct thermal_cooling_device *cdev;
struct cpumask mask_val;
cpumask_set_cpu(0, &mask_val);
cdev = cpufreq_cooling_register(&mask_val);
if (IS_ERR(cdev)) {
dev_err(&pdev->dev, "Failed to register cooling device\n");
return PTR_ERR(cdev);
}
platform_set_drvdata(pdev, cdev);
dev_info(&pdev->dev, "Cooling device registered: %s\n", cdev->type);
return 0;
}
static int db8500_cpufreq_cooling_remove(struct platform_device *pdev)
{
struct thermal_cooling_device *cdev = platform_get_drvdata(pdev);
cpufreq_cooling_unregister(cdev);
return 0;
}
static int db8500_cpufreq_cooling_suspend(struct platform_device *pdev,
pm_message_t state)
{
return -ENOSYS;
}
static int db8500_cpufreq_cooling_resume(struct platform_device *pdev)
{
return -ENOSYS;
}
#ifdef CONFIG_OF
static const struct of_device_id db8500_cpufreq_cooling_match[] = {
{ .compatible = "stericsson,db8500-cpufreq-cooling" },
{},
};
#endif
static struct platform_driver db8500_cpufreq_cooling_driver = {
.driver = {
.owner = THIS_MODULE,
.name = "db8500-cpufreq-cooling",
.of_match_table = of_match_ptr(db8500_cpufreq_cooling_match),
},
.probe = db8500_cpufreq_cooling_probe,
.suspend = db8500_cpufreq_cooling_suspend,
.resume = db8500_cpufreq_cooling_resume,
.remove = db8500_cpufreq_cooling_remove,
};
static int __init db8500_cpufreq_cooling_init(void)
{
return platform_driver_register(&db8500_cpufreq_cooling_driver);
}
static void __exit db8500_cpufreq_cooling_exit(void)
{
platform_driver_unregister(&db8500_cpufreq_cooling_driver);
}
/* Should be later than db8500_cpufreq_register */
late_initcall(db8500_cpufreq_cooling_init);
module_exit(db8500_cpufreq_cooling_exit);
MODULE_AUTHOR("Hongbo Zhang <hongbo.zhang@stericsson.com>");
MODULE_DESCRIPTION("DB8500 cpufreq cooling driver");
MODULE_LICENSE("GPL");