xref: /linux/drivers/input/misc/cobalt_btns.c (revision bebb8a2bc180a4c920c57e89b2d713a34c1d096c)
1 /*
2  *  Cobalt button interface driver.
3  *
4  *  Copyright (C) 2007  Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
5  *
6  *  This program is free software; you can redistribute it and/or modify
7  *  it under the terms of the GNU General Public License as published by
8  *  the Free Software Foundation; either version 2 of the License, or
9  *  (at your option) any later version.
10  *
11  *  This program is distributed in the hope that it will be useful,
12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *  GNU General Public License for more details.
15  *
16  *  You should have received a copy of the GNU General Public License
17  *  along with this program; if not, write to the Free Software
18  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
19  */
20 #include <linux/init.h>
21 #include <linux/input.h>
22 #include <linux/ioport.h>
23 #include <linux/module.h>
24 #include <linux/platform_device.h>
25 #include <linux/jiffies.h>
26 #include <linux/timer.h>
27 
28 #define BUTTONS_POLL_INTERVAL	30	/* msec */
29 #define BUTTONS_COUNT_THRESHOLD	3
30 #define BUTTONS_STATUS_MASK	0xfe000000
31 
32 struct buttons_dev {
33 	struct input_dev *input;
34 	void __iomem *reg;
35 };
36 
37 struct buttons_map {
38 	uint32_t mask;
39 	int keycode;
40 	int count;
41 };
42 
43 static struct buttons_map buttons_map[] = {
44 	{ 0x02000000, KEY_RESTART, },
45 	{ 0x04000000, KEY_LEFT, },
46 	{ 0x08000000, KEY_UP, },
47 	{ 0x10000000, KEY_DOWN, },
48 	{ 0x20000000, KEY_RIGHT, },
49 	{ 0x40000000, KEY_ENTER, },
50 	{ 0x80000000, KEY_SELECT, },
51 };
52 
53 static struct resource cobalt_buttons_resource __initdata = {
54 	.start	= 0x1d000000,
55 	.end	= 0x1d000003,
56 	.flags	= IORESOURCE_MEM,
57 };
58 
59 static struct platform_device *cobalt_buttons_device;
60 
61 static struct timer_list buttons_timer;
62 
63 static void handle_buttons(unsigned long data)
64 {
65 	struct buttons_map *button = buttons_map;
66 	struct buttons_dev *bdev;
67 	uint32_t status;
68 	int i;
69 
70 	bdev = (struct buttons_dev *)data;
71 	status = readl(bdev->reg);
72 	status = ~status & BUTTONS_STATUS_MASK;
73 
74 	for (i = 0; i < ARRAY_SIZE(buttons_map); i++) {
75 		if (status & button->mask) {
76 			button->count++;
77 		} else {
78 			if (button->count >= BUTTONS_COUNT_THRESHOLD) {
79 				input_report_key(bdev->input, button->keycode, 0);
80 				input_sync(bdev->input);
81 			}
82 			button->count = 0;
83 		}
84 
85 		if (button->count == BUTTONS_COUNT_THRESHOLD) {
86 			input_report_key(bdev->input, button->keycode, 1);
87 			input_sync(bdev->input);
88 		}
89 
90 		button++;
91 	}
92 
93 	mod_timer(&buttons_timer, jiffies + msecs_to_jiffies(BUTTONS_POLL_INTERVAL));
94 }
95 
96 static int cobalt_buttons_open(struct input_dev *dev)
97 {
98 	mod_timer(&buttons_timer, jiffies + msecs_to_jiffies(BUTTONS_POLL_INTERVAL));
99 
100 	return 0;
101 }
102 
103 static void cobalt_buttons_close(struct input_dev *dev)
104 {
105 	del_timer_sync(&buttons_timer);
106 }
107 
108 static int __devinit cobalt_buttons_probe(struct platform_device *pdev)
109 {
110 	struct buttons_dev *bdev;
111 	struct input_dev *input;
112 	struct resource *res;
113 	int error, i;
114 
115 	bdev = kzalloc(sizeof(struct buttons_dev), GFP_KERNEL);
116 	input = input_allocate_device();
117 	if (!bdev || !input) {
118 		error = -ENOMEM;
119 		goto err_free_mem;
120 	}
121 
122 	input->name = "Cobalt buttons";
123 	input->phys = "cobalt/input0";
124 	input->id.bustype = BUS_HOST;
125 	input->cdev.dev = &pdev->dev;
126 	input->open = cobalt_buttons_open;
127 	input->close = cobalt_buttons_close;
128 
129 	input->evbit[0] = BIT(EV_KEY);
130 	for (i = 0; i < ARRAY_SIZE(buttons_map); i++) {
131 		set_bit(buttons_map[i].keycode, input->keybit);
132 		buttons_map[i].count = 0;
133 	}
134 
135 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
136 	if (!res) {
137 		error = -EBUSY;
138 		goto err_free_mem;
139 	}
140 
141 	bdev->input = input;
142 	bdev->reg = ioremap(res->start, res->end - res->start + 1);
143 	dev_set_drvdata(&pdev->dev, bdev);
144 
145 	setup_timer(&buttons_timer, handle_buttons, (unsigned long)bdev);
146 
147 	error = input_register_device(input);
148 	if (error)
149 		goto err_iounmap;
150 
151 	return 0;
152 
153  err_iounmap:
154 	iounmap(bdev->reg);
155  err_free_mem:
156 	input_free_device(input);
157 	kfree(bdev);
158 	dev_set_drvdata(&pdev->dev, NULL);
159 	return error;
160 }
161 
162 static int __devexit cobalt_buttons_remove(struct platform_device *pdev)
163 {
164 	struct device *dev = &pdev->dev;
165 	struct buttons_dev *bdev = dev_get_drvdata(dev);
166 
167 	input_unregister_device(bdev->input);
168 	iounmap(bdev->reg);
169 	kfree(bdev);
170 	dev_set_drvdata(dev, NULL);
171 
172 	return 0;
173 }
174 
175 static struct platform_driver cobalt_buttons_driver = {
176 	.probe	= cobalt_buttons_probe,
177 	.remove	= __devexit_p(cobalt_buttons_remove),
178 	.driver	= {
179 		.name	= "Cobalt buttons",
180 		.owner	= THIS_MODULE,
181 	},
182 };
183 
184 static int __init cobalt_buttons_init(void)
185 {
186 	int retval;
187 
188 	cobalt_buttons_device = platform_device_register_simple("Cobalt buttons", -1,
189 	                                                        &cobalt_buttons_resource, 1);
190 	if (IS_ERR(cobalt_buttons_device)) {
191 		retval = PTR_ERR(cobalt_buttons_device);
192 		return retval;
193 	}
194 
195 	retval = platform_driver_register(&cobalt_buttons_driver);
196 	if (retval < 0)
197 		platform_device_unregister(cobalt_buttons_device);
198 
199 	return retval;
200 }
201 
202 static void __exit cobalt_buttons_exit(void)
203 {
204 	platform_driver_unregister(&cobalt_buttons_driver);
205 	platform_device_unregister(cobalt_buttons_device);
206 }
207 
208 module_init(cobalt_buttons_init);
209 module_exit(cobalt_buttons_exit);
210