bridge: fix a possible use after free
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / input / misc / ixp4xx-beeper.c
blob1f38302a5951515a767e96d5c29f01af5922768e
1 /*
2 * Generic IXP4xx beeper driver
4 * Copyright (C) 2005 Tower Technologies
6 * based on nslu2-io.c
7 * Copyright (C) 2004 Karen Spearel
9 * Author: Alessandro Zummo <a.zummo@towertech.it>
10 * Maintainers: http://www.nslu2-linux.org/
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License version 2 as
14 * published by the Free Software Foundation.
18 #include <linux/module.h>
19 #include <linux/input.h>
20 #include <linux/delay.h>
21 #include <linux/platform_device.h>
22 #include <linux/interrupt.h>
23 #include <mach/hardware.h>
25 MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
26 MODULE_DESCRIPTION("ixp4xx beeper driver");
27 MODULE_LICENSE("GPL");
28 MODULE_ALIAS("platform:ixp4xx-beeper");
30 static DEFINE_SPINLOCK(beep_lock);
32 static void ixp4xx_spkr_control(unsigned int pin, unsigned int count)
34 unsigned long flags;
36 spin_lock_irqsave(&beep_lock, flags);
38 if (count) {
39 gpio_line_config(pin, IXP4XX_GPIO_OUT);
40 gpio_line_set(pin, IXP4XX_GPIO_LOW);
42 *IXP4XX_OSRT2 = (count & ~IXP4XX_OST_RELOAD_MASK) | IXP4XX_OST_ENABLE;
43 } else {
44 gpio_line_config(pin, IXP4XX_GPIO_IN);
45 gpio_line_set(pin, IXP4XX_GPIO_HIGH);
47 *IXP4XX_OSRT2 = 0;
50 spin_unlock_irqrestore(&beep_lock, flags);
53 static int ixp4xx_spkr_event(struct input_dev *dev, unsigned int type, unsigned int code, int value)
55 unsigned int pin = (unsigned int) input_get_drvdata(dev);
56 unsigned int count = 0;
58 if (type != EV_SND)
59 return -1;
61 switch (code) {
62 case SND_BELL:
63 if (value)
64 value = 1000;
65 case SND_TONE:
66 break;
67 default:
68 return -1;
71 if (value > 20 && value < 32767)
72 count = (IXP4XX_TIMER_FREQ / (value * 4)) - 1;
74 ixp4xx_spkr_control(pin, count);
76 return 0;
79 static irqreturn_t ixp4xx_spkr_interrupt(int irq, void *dev_id)
81 /* clear interrupt */
82 *IXP4XX_OSST = IXP4XX_OSST_TIMER_2_PEND;
84 /* flip the beeper output */
85 *IXP4XX_GPIO_GPOUTR ^= (1 << (unsigned int) dev_id);
87 return IRQ_HANDLED;
90 static int __devinit ixp4xx_spkr_probe(struct platform_device *dev)
92 struct input_dev *input_dev;
93 int err;
95 input_dev = input_allocate_device();
96 if (!input_dev)
97 return -ENOMEM;
99 input_set_drvdata(input_dev, (void *) dev->id);
101 input_dev->name = "ixp4xx beeper",
102 input_dev->phys = "ixp4xx/gpio";
103 input_dev->id.bustype = BUS_HOST;
104 input_dev->id.vendor = 0x001f;
105 input_dev->id.product = 0x0001;
106 input_dev->id.version = 0x0100;
107 input_dev->dev.parent = &dev->dev;
109 input_dev->evbit[0] = BIT_MASK(EV_SND);
110 input_dev->sndbit[0] = BIT_MASK(SND_BELL) | BIT_MASK(SND_TONE);
111 input_dev->event = ixp4xx_spkr_event;
113 err = request_irq(IRQ_IXP4XX_TIMER2, &ixp4xx_spkr_interrupt,
114 IRQF_DISABLED | IRQF_NO_SUSPEND, "ixp4xx-beeper",
115 (void *) dev->id);
116 if (err)
117 goto err_free_device;
119 err = input_register_device(input_dev);
120 if (err)
121 goto err_free_irq;
123 platform_set_drvdata(dev, input_dev);
125 return 0;
127 err_free_irq:
128 free_irq(IRQ_IXP4XX_TIMER2, dev);
129 err_free_device:
130 input_free_device(input_dev);
132 return err;
135 static int __devexit ixp4xx_spkr_remove(struct platform_device *dev)
137 struct input_dev *input_dev = platform_get_drvdata(dev);
138 unsigned int pin = (unsigned int) input_get_drvdata(input_dev);
140 input_unregister_device(input_dev);
141 platform_set_drvdata(dev, NULL);
143 /* turn the speaker off */
144 disable_irq(IRQ_IXP4XX_TIMER2);
145 ixp4xx_spkr_control(pin, 0);
147 free_irq(IRQ_IXP4XX_TIMER2, dev);
149 return 0;
152 static void ixp4xx_spkr_shutdown(struct platform_device *dev)
154 struct input_dev *input_dev = platform_get_drvdata(dev);
155 unsigned int pin = (unsigned int) input_get_drvdata(input_dev);
157 /* turn off the speaker */
158 disable_irq(IRQ_IXP4XX_TIMER2);
159 ixp4xx_spkr_control(pin, 0);
162 static struct platform_driver ixp4xx_spkr_platform_driver = {
163 .driver = {
164 .name = "ixp4xx-beeper",
165 .owner = THIS_MODULE,
167 .probe = ixp4xx_spkr_probe,
168 .remove = __devexit_p(ixp4xx_spkr_remove),
169 .shutdown = ixp4xx_spkr_shutdown,
172 static int __init ixp4xx_spkr_init(void)
174 return platform_driver_register(&ixp4xx_spkr_platform_driver);
177 static void __exit ixp4xx_spkr_exit(void)
179 platform_driver_unregister(&ixp4xx_spkr_platform_driver);
182 module_init(ixp4xx_spkr_init);
183 module_exit(ixp4xx_spkr_exit);