xref: /OK3568_Linux_fs/kernel/drivers/input/misc/sgi_btns.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-or-later
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  *  SGI Volume Button interface driver
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  *  Copyright (C) 2008  Thomas Bogendoerfer <tsbogend@alpha.franken.de>
6*4882a593Smuzhiyun  */
7*4882a593Smuzhiyun #include <linux/input.h>
8*4882a593Smuzhiyun #include <linux/ioport.h>
9*4882a593Smuzhiyun #include <linux/module.h>
10*4882a593Smuzhiyun #include <linux/platform_device.h>
11*4882a593Smuzhiyun #include <linux/slab.h>
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun #ifdef CONFIG_SGI_IP22
14*4882a593Smuzhiyun #include <asm/sgi/ioc.h>
15*4882a593Smuzhiyun 
button_status(void)16*4882a593Smuzhiyun static inline u8 button_status(void)
17*4882a593Smuzhiyun {
18*4882a593Smuzhiyun 	u8 status;
19*4882a593Smuzhiyun 
20*4882a593Smuzhiyun 	status = readb(&sgioc->panel) ^ 0xa0;
21*4882a593Smuzhiyun 	return ((status & 0x80) >> 6) | ((status & 0x20) >> 5);
22*4882a593Smuzhiyun }
23*4882a593Smuzhiyun #endif
24*4882a593Smuzhiyun 
25*4882a593Smuzhiyun #ifdef CONFIG_SGI_IP32
26*4882a593Smuzhiyun #include <asm/ip32/mace.h>
27*4882a593Smuzhiyun 
button_status(void)28*4882a593Smuzhiyun static inline u8 button_status(void)
29*4882a593Smuzhiyun {
30*4882a593Smuzhiyun 	u64 status;
31*4882a593Smuzhiyun 
32*4882a593Smuzhiyun 	status = readq(&mace->perif.audio.control);
33*4882a593Smuzhiyun 	writeq(status & ~(3U << 23), &mace->perif.audio.control);
34*4882a593Smuzhiyun 
35*4882a593Smuzhiyun 	return (status >> 23) & 3;
36*4882a593Smuzhiyun }
37*4882a593Smuzhiyun #endif
38*4882a593Smuzhiyun 
39*4882a593Smuzhiyun #define BUTTONS_POLL_INTERVAL	30	/* msec */
40*4882a593Smuzhiyun #define BUTTONS_COUNT_THRESHOLD	3
41*4882a593Smuzhiyun 
42*4882a593Smuzhiyun static const unsigned short sgi_map[] = {
43*4882a593Smuzhiyun 	KEY_VOLUMEDOWN,
44*4882a593Smuzhiyun 	KEY_VOLUMEUP
45*4882a593Smuzhiyun };
46*4882a593Smuzhiyun 
47*4882a593Smuzhiyun struct buttons_dev {
48*4882a593Smuzhiyun 	unsigned short keymap[ARRAY_SIZE(sgi_map)];
49*4882a593Smuzhiyun 	int count[ARRAY_SIZE(sgi_map)];
50*4882a593Smuzhiyun };
51*4882a593Smuzhiyun 
handle_buttons(struct input_dev * input)52*4882a593Smuzhiyun static void handle_buttons(struct input_dev *input)
53*4882a593Smuzhiyun {
54*4882a593Smuzhiyun 	struct buttons_dev *bdev = input_get_drvdata(input);
55*4882a593Smuzhiyun 	u8 status;
56*4882a593Smuzhiyun 	int i;
57*4882a593Smuzhiyun 
58*4882a593Smuzhiyun 	status = button_status();
59*4882a593Smuzhiyun 
60*4882a593Smuzhiyun 	for (i = 0; i < ARRAY_SIZE(bdev->keymap); i++) {
61*4882a593Smuzhiyun 		if (status & (1U << i)) {
62*4882a593Smuzhiyun 			if (++bdev->count[i] == BUTTONS_COUNT_THRESHOLD) {
63*4882a593Smuzhiyun 				input_event(input, EV_MSC, MSC_SCAN, i);
64*4882a593Smuzhiyun 				input_report_key(input, bdev->keymap[i], 1);
65*4882a593Smuzhiyun 				input_sync(input);
66*4882a593Smuzhiyun 			}
67*4882a593Smuzhiyun 		} else {
68*4882a593Smuzhiyun 			if (bdev->count[i] >= BUTTONS_COUNT_THRESHOLD) {
69*4882a593Smuzhiyun 				input_event(input, EV_MSC, MSC_SCAN, i);
70*4882a593Smuzhiyun 				input_report_key(input, bdev->keymap[i], 0);
71*4882a593Smuzhiyun 				input_sync(input);
72*4882a593Smuzhiyun 			}
73*4882a593Smuzhiyun 			bdev->count[i] = 0;
74*4882a593Smuzhiyun 		}
75*4882a593Smuzhiyun 	}
76*4882a593Smuzhiyun }
77*4882a593Smuzhiyun 
sgi_buttons_probe(struct platform_device * pdev)78*4882a593Smuzhiyun static int sgi_buttons_probe(struct platform_device *pdev)
79*4882a593Smuzhiyun {
80*4882a593Smuzhiyun 	struct buttons_dev *bdev;
81*4882a593Smuzhiyun 	struct input_dev *input;
82*4882a593Smuzhiyun 	int error, i;
83*4882a593Smuzhiyun 
84*4882a593Smuzhiyun 	bdev = devm_kzalloc(&pdev->dev, sizeof(*bdev), GFP_KERNEL);
85*4882a593Smuzhiyun 	if (!bdev)
86*4882a593Smuzhiyun 		return -ENOMEM;
87*4882a593Smuzhiyun 
88*4882a593Smuzhiyun 	input = devm_input_allocate_device(&pdev->dev);
89*4882a593Smuzhiyun 	if (!input)
90*4882a593Smuzhiyun 		return -ENOMEM;
91*4882a593Smuzhiyun 
92*4882a593Smuzhiyun 	memcpy(bdev->keymap, sgi_map, sizeof(bdev->keymap));
93*4882a593Smuzhiyun 
94*4882a593Smuzhiyun 	input_set_drvdata(input, bdev);
95*4882a593Smuzhiyun 
96*4882a593Smuzhiyun 	input->name = "SGI buttons";
97*4882a593Smuzhiyun 	input->phys = "sgi/input0";
98*4882a593Smuzhiyun 	input->id.bustype = BUS_HOST;
99*4882a593Smuzhiyun 
100*4882a593Smuzhiyun 	input->keycode = bdev->keymap;
101*4882a593Smuzhiyun 	input->keycodemax = ARRAY_SIZE(bdev->keymap);
102*4882a593Smuzhiyun 	input->keycodesize = sizeof(unsigned short);
103*4882a593Smuzhiyun 
104*4882a593Smuzhiyun 	input_set_capability(input, EV_MSC, MSC_SCAN);
105*4882a593Smuzhiyun 	__set_bit(EV_KEY, input->evbit);
106*4882a593Smuzhiyun 	for (i = 0; i < ARRAY_SIZE(sgi_map); i++)
107*4882a593Smuzhiyun 		__set_bit(bdev->keymap[i], input->keybit);
108*4882a593Smuzhiyun 	__clear_bit(KEY_RESERVED, input->keybit);
109*4882a593Smuzhiyun 
110*4882a593Smuzhiyun 	error = input_setup_polling(input, handle_buttons);
111*4882a593Smuzhiyun 	if (error)
112*4882a593Smuzhiyun 		return error;
113*4882a593Smuzhiyun 
114*4882a593Smuzhiyun 	input_set_poll_interval(input, BUTTONS_POLL_INTERVAL);
115*4882a593Smuzhiyun 
116*4882a593Smuzhiyun 	error = input_register_device(input);
117*4882a593Smuzhiyun 	if (error)
118*4882a593Smuzhiyun 		return error;
119*4882a593Smuzhiyun 
120*4882a593Smuzhiyun 	return 0;
121*4882a593Smuzhiyun }
122*4882a593Smuzhiyun 
123*4882a593Smuzhiyun static struct platform_driver sgi_buttons_driver = {
124*4882a593Smuzhiyun 	.probe	= sgi_buttons_probe,
125*4882a593Smuzhiyun 	.driver	= {
126*4882a593Smuzhiyun 		.name	= "sgibtns",
127*4882a593Smuzhiyun 	},
128*4882a593Smuzhiyun };
129*4882a593Smuzhiyun module_platform_driver(sgi_buttons_driver);
130*4882a593Smuzhiyun 
131*4882a593Smuzhiyun MODULE_LICENSE("GPL");
132