5019cd6114
The .remove() callback for a platform driver returns an int which makes many driver authors wrongly assume it's possible to do error handling by returning an error code. However the value returned is ignored (apart from emitting a warning) and this typically results in resource leaks. To improve here there is a quest to make the remove callback return void. In the first step of this quest all drivers are converted to .remove_new(), which already returns void. Eventually after all drivers are converted, .remove_new() will be renamed to .remove(). Trivially convert this driver from always returning zero in the remove callback to the void returning variant. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Link: https://lore.kernel.org/r/20240306211947.97103-2-u.kleine-koenig@pengutronix.de Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
134 lines
2.9 KiB
C
134 lines
2.9 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Generic push-switch framework
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*
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* Copyright (C) 2006 Paul Mundt
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*/
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#include <linux/init.h>
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#include <linux/slab.h>
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#include <linux/module.h>
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#include <linux/interrupt.h>
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#include <linux/platform_device.h>
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#include <asm/push-switch.h>
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#define DRV_NAME "push-switch"
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#define DRV_VERSION "0.1.1"
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static ssize_t switch_show(struct device *dev,
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struct device_attribute *attr,
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char *buf)
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{
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struct push_switch_platform_info *psw_info = dev->platform_data;
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return sprintf(buf, "%s\n", psw_info->name);
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}
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static DEVICE_ATTR_RO(switch);
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static void switch_timer(struct timer_list *t)
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{
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struct push_switch *psw = from_timer(psw, t, debounce);
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schedule_work(&psw->work);
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}
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static void switch_work_handler(struct work_struct *work)
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{
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struct push_switch *psw = container_of(work, struct push_switch, work);
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struct platform_device *pdev = psw->pdev;
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psw->state = 0;
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kobject_uevent(&pdev->dev.kobj, KOBJ_CHANGE);
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}
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static int switch_drv_probe(struct platform_device *pdev)
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{
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struct push_switch_platform_info *psw_info;
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struct push_switch *psw;
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int ret, irq;
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psw = kzalloc(sizeof(struct push_switch), GFP_KERNEL);
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if (unlikely(!psw))
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return -ENOMEM;
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irq = platform_get_irq(pdev, 0);
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if (unlikely(irq < 0)) {
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ret = -ENODEV;
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goto err;
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}
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psw_info = pdev->dev.platform_data;
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BUG_ON(!psw_info);
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ret = request_irq(irq, psw_info->irq_handler,
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psw_info->irq_flags,
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psw_info->name ? psw_info->name : DRV_NAME, pdev);
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if (unlikely(ret < 0))
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goto err;
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if (psw_info->name) {
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ret = device_create_file(&pdev->dev, &dev_attr_switch);
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if (unlikely(ret)) {
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dev_err(&pdev->dev, "Failed creating device attrs\n");
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ret = -EINVAL;
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goto err_irq;
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}
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}
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INIT_WORK(&psw->work, switch_work_handler);
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timer_setup(&psw->debounce, switch_timer, 0);
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/* Workqueue API brain-damage */
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psw->pdev = pdev;
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platform_set_drvdata(pdev, psw);
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return 0;
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err_irq:
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free_irq(irq, pdev);
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err:
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kfree(psw);
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return ret;
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}
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static void switch_drv_remove(struct platform_device *pdev)
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{
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struct push_switch *psw = platform_get_drvdata(pdev);
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struct push_switch_platform_info *psw_info = pdev->dev.platform_data;
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int irq = platform_get_irq(pdev, 0);
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if (psw_info->name)
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device_remove_file(&pdev->dev, &dev_attr_switch);
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platform_set_drvdata(pdev, NULL);
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timer_shutdown_sync(&psw->debounce);
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flush_work(&psw->work);
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free_irq(irq, pdev);
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kfree(psw);
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}
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static struct platform_driver switch_driver = {
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.probe = switch_drv_probe,
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.remove_new = switch_drv_remove,
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.driver = {
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.name = DRV_NAME,
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},
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};
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static int __init switch_init(void)
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{
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printk(KERN_NOTICE DRV_NAME ": version %s loaded\n", DRV_VERSION);
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return platform_driver_register(&switch_driver);
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}
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static void __exit switch_exit(void)
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{
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platform_driver_unregister(&switch_driver);
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}
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module_init(switch_init);
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module_exit(switch_exit);
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MODULE_VERSION(DRV_VERSION);
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MODULE_AUTHOR("Paul Mundt");
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MODULE_LICENSE("GPL v2");
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