Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 | // SPDX-License-Identifier: GPL-2.0 /* * Generic push-switch framework * * Copyright (C) 2006 Paul Mundt */ #include <linux/init.h> #include <linux/slab.h> #include <linux/module.h> #include <linux/interrupt.h> #include <linux/platform_device.h> #include <asm/push-switch.h> #define DRV_NAME "push-switch" #define DRV_VERSION "0.1.1" static ssize_t switch_show(struct device *dev, struct device_attribute *attr, char *buf) { struct push_switch_platform_info *psw_info = dev->platform_data; return sprintf(buf, "%s\n", psw_info->name); } static DEVICE_ATTR_RO(switch); static void switch_timer(struct timer_list *t) { struct push_switch *psw = from_timer(psw, t, debounce); schedule_work(&psw->work); } static void switch_work_handler(struct work_struct *work) { struct push_switch *psw = container_of(work, struct push_switch, work); struct platform_device *pdev = psw->pdev; psw->state = 0; kobject_uevent(&pdev->dev.kobj, KOBJ_CHANGE); } static int switch_drv_probe(struct platform_device *pdev) { struct push_switch_platform_info *psw_info; struct push_switch *psw; int ret, irq; psw = kzalloc(sizeof(struct push_switch), GFP_KERNEL); if (unlikely(!psw)) return -ENOMEM; irq = platform_get_irq(pdev, 0); if (unlikely(irq < 0)) { ret = -ENODEV; goto err; } psw_info = pdev->dev.platform_data; BUG_ON(!psw_info); ret = request_irq(irq, psw_info->irq_handler, psw_info->irq_flags, psw_info->name ? psw_info->name : DRV_NAME, pdev); if (unlikely(ret < 0)) goto err; if (psw_info->name) { ret = device_create_file(&pdev->dev, &dev_attr_switch); if (unlikely(ret)) { dev_err(&pdev->dev, "Failed creating device attrs\n"); ret = -EINVAL; goto err_irq; } } INIT_WORK(&psw->work, switch_work_handler); timer_setup(&psw->debounce, switch_timer, 0); /* Workqueue API brain-damage */ psw->pdev = pdev; platform_set_drvdata(pdev, psw); return 0; err_irq: free_irq(irq, pdev); err: kfree(psw); return ret; } static int switch_drv_remove(struct platform_device *pdev) { struct push_switch *psw = platform_get_drvdata(pdev); struct push_switch_platform_info *psw_info = pdev->dev.platform_data; int irq = platform_get_irq(pdev, 0); if (psw_info->name) device_remove_file(&pdev->dev, &dev_attr_switch); platform_set_drvdata(pdev, NULL); flush_work(&psw->work); del_timer_sync(&psw->debounce); free_irq(irq, pdev); kfree(psw); return 0; } static struct platform_driver switch_driver = { .probe = switch_drv_probe, .remove = switch_drv_remove, .driver = { .name = DRV_NAME, }, }; static int __init switch_init(void) { printk(KERN_NOTICE DRV_NAME ": version %s loaded\n", DRV_VERSION); return platform_driver_register(&switch_driver); } static void __exit switch_exit(void) { platform_driver_unregister(&switch_driver); } module_init(switch_init); module_exit(switch_exit); MODULE_VERSION(DRV_VERSION); MODULE_AUTHOR("Paul Mundt"); MODULE_LICENSE("GPL v2"); |