GNU Linux-libre 4.14.266-gnu1
[releases.git] / drivers / input / misc / cobalt_btns.c
1 /*
2  *  Cobalt button interface driver.
3  *
4  *  Copyright (C) 2007-2008  Yoichi Yuasa <yuasa@linux-mips.org>
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/input-polldev.h>
21 #include <linux/ioport.h>
22 #include <linux/module.h>
23 #include <linux/platform_device.h>
24 #include <linux/slab.h>
25
26 #define BUTTONS_POLL_INTERVAL   30      /* msec */
27 #define BUTTONS_COUNT_THRESHOLD 3
28 #define BUTTONS_STATUS_MASK     0xfe000000
29
30 static const unsigned short cobalt_map[] = {
31         KEY_RESERVED,
32         KEY_RESTART,
33         KEY_LEFT,
34         KEY_UP,
35         KEY_DOWN,
36         KEY_RIGHT,
37         KEY_ENTER,
38         KEY_SELECT
39 };
40
41 struct buttons_dev {
42         struct input_polled_dev *poll_dev;
43         unsigned short keymap[ARRAY_SIZE(cobalt_map)];
44         int count[ARRAY_SIZE(cobalt_map)];
45         void __iomem *reg;
46 };
47
48 static void handle_buttons(struct input_polled_dev *dev)
49 {
50         struct buttons_dev *bdev = dev->private;
51         struct input_dev *input = dev->input;
52         uint32_t status;
53         int i;
54
55         status = ~readl(bdev->reg) >> 24;
56
57         for (i = 0; i < ARRAY_SIZE(bdev->keymap); i++) {
58                 if (status & (1U << i)) {
59                         if (++bdev->count[i] == BUTTONS_COUNT_THRESHOLD) {
60                                 input_event(input, EV_MSC, MSC_SCAN, i);
61                                 input_report_key(input, bdev->keymap[i], 1);
62                                 input_sync(input);
63                         }
64                 } else {
65                         if (bdev->count[i] >= BUTTONS_COUNT_THRESHOLD) {
66                                 input_event(input, EV_MSC, MSC_SCAN, i);
67                                 input_report_key(input, bdev->keymap[i], 0);
68                                 input_sync(input);
69                         }
70                         bdev->count[i] = 0;
71                 }
72         }
73 }
74
75 static int cobalt_buttons_probe(struct platform_device *pdev)
76 {
77         struct buttons_dev *bdev;
78         struct input_polled_dev *poll_dev;
79         struct input_dev *input;
80         struct resource *res;
81         int error, i;
82
83         bdev = kzalloc(sizeof(struct buttons_dev), GFP_KERNEL);
84         poll_dev = input_allocate_polled_device();
85         if (!bdev || !poll_dev) {
86                 error = -ENOMEM;
87                 goto err_free_mem;
88         }
89
90         memcpy(bdev->keymap, cobalt_map, sizeof(bdev->keymap));
91
92         poll_dev->private = bdev;
93         poll_dev->poll = handle_buttons;
94         poll_dev->poll_interval = BUTTONS_POLL_INTERVAL;
95
96         input = poll_dev->input;
97         input->name = "Cobalt buttons";
98         input->phys = "cobalt/input0";
99         input->id.bustype = BUS_HOST;
100         input->dev.parent = &pdev->dev;
101
102         input->keycode = bdev->keymap;
103         input->keycodemax = ARRAY_SIZE(bdev->keymap);
104         input->keycodesize = sizeof(unsigned short);
105
106         input_set_capability(input, EV_MSC, MSC_SCAN);
107         __set_bit(EV_KEY, input->evbit);
108         for (i = 0; i < ARRAY_SIZE(cobalt_map); i++)
109                 __set_bit(bdev->keymap[i], input->keybit);
110         __clear_bit(KEY_RESERVED, input->keybit);
111
112         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
113         if (!res) {
114                 error = -EBUSY;
115                 goto err_free_mem;
116         }
117
118         bdev->poll_dev = poll_dev;
119         bdev->reg = ioremap(res->start, resource_size(res));
120         dev_set_drvdata(&pdev->dev, bdev);
121
122         error = input_register_polled_device(poll_dev);
123         if (error)
124                 goto err_iounmap;
125
126         return 0;
127
128  err_iounmap:
129         iounmap(bdev->reg);
130  err_free_mem:
131         input_free_polled_device(poll_dev);
132         kfree(bdev);
133         return error;
134 }
135
136 static int cobalt_buttons_remove(struct platform_device *pdev)
137 {
138         struct device *dev = &pdev->dev;
139         struct buttons_dev *bdev = dev_get_drvdata(dev);
140
141         input_unregister_polled_device(bdev->poll_dev);
142         input_free_polled_device(bdev->poll_dev);
143         iounmap(bdev->reg);
144         kfree(bdev);
145
146         return 0;
147 }
148
149 MODULE_AUTHOR("Yoichi Yuasa <yuasa@linux-mips.org>");
150 MODULE_DESCRIPTION("Cobalt button interface driver");
151 MODULE_LICENSE("GPL");
152 /* work with hotplug and coldplug */
153 MODULE_ALIAS("platform:Cobalt buttons");
154
155 static struct platform_driver cobalt_buttons_driver = {
156         .probe  = cobalt_buttons_probe,
157         .remove = cobalt_buttons_remove,
158         .driver = {
159                 .name   = "Cobalt buttons",
160         },
161 };
162 module_platform_driver(cobalt_buttons_driver);