kernel/drivers/input/misc/sgi_btns.c
2024-07-22 17:22:30 +08:00

132 lines
2.8 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* SGI Volume Button interface driver
*
* Copyright (C) 2008 Thomas Bogendoerfer <tsbogend@alpha.franken.de>
*/
#include <linux/input.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#ifdef CONFIG_SGI_IP22
#include <asm/sgi/ioc.h>
static inline u8 button_status(void)
{
u8 status;
status = readb(&sgioc->panel) ^ 0xa0;
return ((status & 0x80) >> 6) | ((status & 0x20) >> 5);
}
#endif
#ifdef CONFIG_SGI_IP32
#include <asm/ip32/mace.h>
static inline u8 button_status(void)
{
u64 status;
status = readq(&mace->perif.audio.control);
writeq(status & ~(3U << 23), &mace->perif.audio.control);
return (status >> 23) & 3;
}
#endif
#define BUTTONS_POLL_INTERVAL 30 /* msec */
#define BUTTONS_COUNT_THRESHOLD 3
static const unsigned short sgi_map[] = {
KEY_VOLUMEDOWN,
KEY_VOLUMEUP
};
struct buttons_dev {
unsigned short keymap[ARRAY_SIZE(sgi_map)];
int count[ARRAY_SIZE(sgi_map)];
};
static void handle_buttons(struct input_dev *input)
{
struct buttons_dev *bdev = input_get_drvdata(input);
u8 status;
int i;
status = button_status();
for (i = 0; i < ARRAY_SIZE(bdev->keymap); i++) {
if (status & (1U << i)) {
if (++bdev->count[i] == BUTTONS_COUNT_THRESHOLD) {
input_event(input, EV_MSC, MSC_SCAN, i);
input_report_key(input, bdev->keymap[i], 1);
input_sync(input);
}
} else {
if (bdev->count[i] >= BUTTONS_COUNT_THRESHOLD) {
input_event(input, EV_MSC, MSC_SCAN, i);
input_report_key(input, bdev->keymap[i], 0);
input_sync(input);
}
bdev->count[i] = 0;
}
}
}
static int sgi_buttons_probe(struct platform_device *pdev)
{
struct buttons_dev *bdev;
struct input_dev *input;
int error, i;
bdev = devm_kzalloc(&pdev->dev, sizeof(*bdev), GFP_KERNEL);
if (!bdev)
return -ENOMEM;
input = devm_input_allocate_device(&pdev->dev);
if (!input)
return -ENOMEM;
memcpy(bdev->keymap, sgi_map, sizeof(bdev->keymap));
input_set_drvdata(input, bdev);
input->name = "SGI buttons";
input->phys = "sgi/input0";
input->id.bustype = BUS_HOST;
input->keycode = bdev->keymap;
input->keycodemax = ARRAY_SIZE(bdev->keymap);
input->keycodesize = sizeof(unsigned short);
input_set_capability(input, EV_MSC, MSC_SCAN);
__set_bit(EV_KEY, input->evbit);
for (i = 0; i < ARRAY_SIZE(sgi_map); i++)
__set_bit(bdev->keymap[i], input->keybit);
__clear_bit(KEY_RESERVED, input->keybit);
error = input_setup_polling(input, handle_buttons);
if (error)
return error;
input_set_poll_interval(input, BUTTONS_POLL_INTERVAL);
error = input_register_device(input);
if (error)
return error;
return 0;
}
static struct platform_driver sgi_buttons_driver = {
.probe = sgi_buttons_probe,
.driver = {
.name = "sgibtns",
},
};
module_platform_driver(sgi_buttons_driver);
MODULE_LICENSE("GPL");