LXR linux/drivers/input/misc/sgi

   1/*
   2 *  SGI Volume Button interface driver
   3 *
   4 *  Copyright (C) 2008  Thomas Bogendoerfer <tsbogend@alpha.franken.de>
   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#ifdef CONFIG_SGI_IP22
  27#include <asm/sgi/ioc.h>
  28
  29static inline u8 button_status(void)
  30{
  31        u8 status;
  32
  33        status = readb(&sgioc->panel) ^ 0xa0;
  34        return ((status & 0x80) >> 6) | ((status & 0x20) >> 5);
  35}
  36#endif
  37
  38#ifdef CONFIG_SGI_IP32
  39#include <asm/ip32/mace.h>
  40
  41static inline u8 button_status(void)
  42{
  43        u64 status;
  44
  45        status = readq(&mace->perif.audio.control);
  46        writeq(status & ~(3U << 23), &mace->perif.audio.control);
  47
  48        return (status >> 23) & 3;
  49}
  50#endif
  51
  52#define BUTTONS_POLL_INTERVAL   30      /* msec */
  53#define BUTTONS_COUNT_THRESHOLD 3
  54
  55static const unsigned short sgi_map[] = {
  56        KEY_VOLUMEDOWN,
  57        KEY_VOLUMEUP
  58};
  59
  60struct buttons_dev {
  61        struct input_polled_dev *poll_dev;
  62        unsigned short keymap[ARRAY_SIZE(sgi_map)];
  63        int count[ARRAY_SIZE(sgi_map)];
  64};
  65
  66static void handle_buttons(struct input_polled_dev *dev)
  67{
  68        struct buttons_dev *bdev = dev->private;
  69        struct input_dev *input = dev->input;
  70        u8 status;
  71        int i;
  72
  73        status = button_status();
  74
  75        for (i = 0; i < ARRAY_SIZE(bdev->keymap); i++) {
  76                if (status & (1U << i)) {
  77                        if (++bdev->count[i] == BUTTONS_COUNT_THRESHOLD) {
  78                                input_event(input, EV_MSC, MSC_SCAN, i);
  79                                input_report_key(input, bdev->keymap[i], 1);
  80                                input_sync(input);
  81                        }
  82                } else {
  83                        if (bdev->count[i] >= BUTTONS_COUNT_THRESHOLD) {
  84                                input_event(input, EV_MSC, MSC_SCAN, i);
  85                                input_report_key(input, bdev->keymap[i], 0);
  86                                input_sync(input);
  87                        }
  88                        bdev->count[i] = 0;
  89                }
  90        }
  91}
  92
  93static int sgi_buttons_probe(struct platform_device *pdev)
  94{
  95        struct buttons_dev *bdev;
  96        struct input_polled_dev *poll_dev;
  97        struct input_dev *input;
  98        int error, i;
  99
 100        bdev = kzalloc(sizeof(struct buttons_dev), GFP_KERNEL);
 101        poll_dev = input_allocate_polled_device();
 102        if (!bdev || !poll_dev) {
 103                error = -ENOMEM;
 104                goto err_free_mem;
 105        }
 106
 107        memcpy(bdev->keymap, sgi_map, sizeof(bdev->keymap));
 108
 109        poll_dev->private = bdev;
 110        poll_dev->poll = handle_buttons;
 111        poll_dev->poll_interval = BUTTONS_POLL_INTERVAL;
 112
 113        input = poll_dev->input;
 114        input->name = "SGI buttons";
 115        input->phys = "sgi/input0";
 116        input->id.bustype = BUS_HOST;
 117        input->dev.parent = &pdev->dev;
 118
 119        input->keycode = bdev->keymap;
 120        input->keycodemax = ARRAY_SIZE(bdev->keymap);
 121        input->keycodesize = sizeof(unsigned short);
 122
 123        input_set_capability(input, EV_MSC, MSC_SCAN);
 124        __set_bit(EV_KEY, input->evbit);
 125        for (i = 0; i < ARRAY_SIZE(sgi_map); i++)
 126                __set_bit(bdev->keymap[i], input->keybit);
 127        __clear_bit(KEY_RESERVED, input->keybit);
 128
 129        bdev->poll_dev = poll_dev;
 130        platform_set_drvdata(pdev, bdev);
 131
 132        error = input_register_polled_device(poll_dev);
 133        if (error)
 134                goto err_free_mem;
 135
 136        return 0;
 137
 138 err_free_mem:
 139        input_free_polled_device(poll_dev);
 140        kfree(bdev);
 141        return error;
 142}
 143
 144static int sgi_buttons_remove(struct platform_device *pdev)
 145{
 146        struct buttons_dev *bdev = platform_get_drvdata(pdev);
 147
 148        input_unregister_polled_device(bdev->poll_dev);
 149        input_free_polled_device(bdev->poll_dev);
 150        kfree(bdev);
 151
 152        return 0;
 153}
 154
 155static struct platform_driver sgi_buttons_driver = {
 156        .probe  = sgi_buttons_probe,
 157        .remove = sgi_buttons_remove,
 158        .driver = {
 159                .name   = "sgibtns",
 160        },
 161};
 162module_platform_driver(sgi_buttons_driver);
 163
 164MODULE_LICENSE("GPL");
 165