Linux kernel mirror (for testing)
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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * SGI Volume Button interface driver
4 *
5 * Copyright (C) 2008 Thomas Bogendoerfer <tsbogend@alpha.franken.de>
6 */
7#include <linux/input-polldev.h>
8#include <linux/ioport.h>
9#include <linux/module.h>
10#include <linux/platform_device.h>
11#include <linux/slab.h>
12
13#ifdef CONFIG_SGI_IP22
14#include <asm/sgi/ioc.h>
15
16static inline u8 button_status(void)
17{
18 u8 status;
19
20 status = readb(&sgioc->panel) ^ 0xa0;
21 return ((status & 0x80) >> 6) | ((status & 0x20) >> 5);
22}
23#endif
24
25#ifdef CONFIG_SGI_IP32
26#include <asm/ip32/mace.h>
27
28static inline u8 button_status(void)
29{
30 u64 status;
31
32 status = readq(&mace->perif.audio.control);
33 writeq(status & ~(3U << 23), &mace->perif.audio.control);
34
35 return (status >> 23) & 3;
36}
37#endif
38
39#define BUTTONS_POLL_INTERVAL 30 /* msec */
40#define BUTTONS_COUNT_THRESHOLD 3
41
42static const unsigned short sgi_map[] = {
43 KEY_VOLUMEDOWN,
44 KEY_VOLUMEUP
45};
46
47struct buttons_dev {
48 struct input_polled_dev *poll_dev;
49 unsigned short keymap[ARRAY_SIZE(sgi_map)];
50 int count[ARRAY_SIZE(sgi_map)];
51};
52
53static void handle_buttons(struct input_polled_dev *dev)
54{
55 struct buttons_dev *bdev = dev->private;
56 struct input_dev *input = dev->input;
57 u8 status;
58 int i;
59
60 status = button_status();
61
62 for (i = 0; i < ARRAY_SIZE(bdev->keymap); i++) {
63 if (status & (1U << i)) {
64 if (++bdev->count[i] == BUTTONS_COUNT_THRESHOLD) {
65 input_event(input, EV_MSC, MSC_SCAN, i);
66 input_report_key(input, bdev->keymap[i], 1);
67 input_sync(input);
68 }
69 } else {
70 if (bdev->count[i] >= BUTTONS_COUNT_THRESHOLD) {
71 input_event(input, EV_MSC, MSC_SCAN, i);
72 input_report_key(input, bdev->keymap[i], 0);
73 input_sync(input);
74 }
75 bdev->count[i] = 0;
76 }
77 }
78}
79
80static int sgi_buttons_probe(struct platform_device *pdev)
81{
82 struct buttons_dev *bdev;
83 struct input_polled_dev *poll_dev;
84 struct input_dev *input;
85 int error, i;
86
87 bdev = kzalloc(sizeof(struct buttons_dev), GFP_KERNEL);
88 poll_dev = input_allocate_polled_device();
89 if (!bdev || !poll_dev) {
90 error = -ENOMEM;
91 goto err_free_mem;
92 }
93
94 memcpy(bdev->keymap, sgi_map, sizeof(bdev->keymap));
95
96 poll_dev->private = bdev;
97 poll_dev->poll = handle_buttons;
98 poll_dev->poll_interval = BUTTONS_POLL_INTERVAL;
99
100 input = poll_dev->input;
101 input->name = "SGI buttons";
102 input->phys = "sgi/input0";
103 input->id.bustype = BUS_HOST;
104 input->dev.parent = &pdev->dev;
105
106 input->keycode = bdev->keymap;
107 input->keycodemax = ARRAY_SIZE(bdev->keymap);
108 input->keycodesize = sizeof(unsigned short);
109
110 input_set_capability(input, EV_MSC, MSC_SCAN);
111 __set_bit(EV_KEY, input->evbit);
112 for (i = 0; i < ARRAY_SIZE(sgi_map); i++)
113 __set_bit(bdev->keymap[i], input->keybit);
114 __clear_bit(KEY_RESERVED, input->keybit);
115
116 bdev->poll_dev = poll_dev;
117 platform_set_drvdata(pdev, bdev);
118
119 error = input_register_polled_device(poll_dev);
120 if (error)
121 goto err_free_mem;
122
123 return 0;
124
125 err_free_mem:
126 input_free_polled_device(poll_dev);
127 kfree(bdev);
128 return error;
129}
130
131static int sgi_buttons_remove(struct platform_device *pdev)
132{
133 struct buttons_dev *bdev = platform_get_drvdata(pdev);
134
135 input_unregister_polled_device(bdev->poll_dev);
136 input_free_polled_device(bdev->poll_dev);
137 kfree(bdev);
138
139 return 0;
140}
141
142static struct platform_driver sgi_buttons_driver = {
143 .probe = sgi_buttons_probe,
144 .remove = sgi_buttons_remove,
145 .driver = {
146 .name = "sgibtns",
147 },
148};
149module_platform_driver(sgi_buttons_driver);
150
151MODULE_LICENSE("GPL");