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/init.h>
  21#include <linux/input-polldev.h>
  22#include <linux/ioport.h>
  23#include <linux/module.h>
  24#include <linux/platform_device.h>
  25#include <linux/slab.h>
  26
  27#ifdef CONFIG_SGI_IP22
  28#include <asm/sgi/ioc.h>
  29
  30static inline u8 button_status(void)
  31{
  32        u8 status;
  33
  34        status = readb(&sgioc->panel) ^ 0xa0;
  35        return ((status & 0x80) >> 6) | ((status & 0x20) >> 5);
  36}
  37#endif
  38
  39#ifdef CONFIG_SGI_IP32
  40#include <asm/ip32/mace.h>
  41
  42static inline u8 button_status(void)
  43{
  44        u64 status;
  45
  46        status = readq(&mace->perif.audio.control);
  47        writeq(status & ~(3U << 23), &mace->perif.audio.control);
  48
  49        return (status >> 23) & 3;
  50}
  51#endif
  52
  53#define BUTTONS_POLL_INTERVAL   30      /* msec */
  54#define BUTTONS_COUNT_THRESHOLD 3
  55
  56static const unsigned short sgi_map[] = {
  57        KEY_VOLUMEDOWN,
  58        KEY_VOLUMEUP
  59};
  60
  61struct buttons_dev {
  62        struct input_polled_dev *poll_dev;
  63        unsigned short keymap[ARRAY_SIZE(sgi_map)];
  64        int count[ARRAY_SIZE(sgi_map)];
  65};
  66
  67static void handle_buttons(struct input_polled_dev *dev)
  68{
  69        struct buttons_dev *bdev = dev->private;
  70        struct input_dev *input = dev->input;
  71        u8 status;
  72        int i;
  73
  74        status = button_status();
  75
  76        for (i = 0; i < ARRAY_SIZE(bdev->keymap); i++) {
  77                if (status & (1U << i)) {
  78                        if (++bdev->count[i] == BUTTONS_COUNT_THRESHOLD) {
  79                                input_event(input, EV_MSC, MSC_SCAN, i);
  80                                input_report_key(input, bdev->keymap[i], 1);
  81                                input_sync(input);
  82                        }
  83                } else {
  84                        if (bdev->count[i] >= BUTTONS_COUNT_THRESHOLD) {
  85                                input_event(input, EV_MSC, MSC_SCAN, i);
  86                                input_report_key(input, bdev->keymap[i], 0);
  87                                input_sync(input);
  88                        }
  89                        bdev->count[i] = 0;
  90                }
  91        }
  92}
  93
  94static int __devinit sgi_buttons_probe(struct platform_device *pdev)
  95{
  96        struct buttons_dev *bdev;
  97        struct input_polled_dev *poll_dev;
  98        struct input_dev *input;
  99        int error, i;
 100
 101        bdev = kzalloc(sizeof(struct buttons_dev), GFP_KERNEL);
 102        poll_dev = input_allocate_polled_device();
 103        if (!bdev || !poll_dev) {
 104                error = -ENOMEM;
 105                goto err_free_mem;
 106        }
 107
 108        memcpy(bdev->keymap, sgi_map, sizeof(bdev->keymap));
 109
 110        poll_dev->private = bdev;
 111        poll_dev->poll = handle_buttons;
 112        poll_dev->poll_interval = BUTTONS_POLL_INTERVAL;
 113
 114        input = poll_dev->input;
 115        input->name = "SGI buttons";
 116        input->phys = "sgi/input0";
 117        input->id.bustype = BUS_HOST;
 118        input->dev.parent = &pdev->dev;
 119
 120        input->keycode = bdev->keymap;
 121        input->keycodemax = ARRAY_SIZE(bdev->keymap);
 122        input->keycodesize = sizeof(unsigned short);
 123
 124        input_set_capability(input, EV_MSC, MSC_SCAN);
 125        __set_bit(EV_KEY, input->evbit);
 126        for (i = 0; i < ARRAY_SIZE(sgi_map); i++)
 127                __set_bit(bdev->keymap[i], input->keybit);
 128        __clear_bit(KEY_RESERVED, input->keybit);
 129
 130        bdev->poll_dev = poll_dev;
 131        dev_set_drvdata(&pdev->dev, bdev);
 132
 133        error = input_register_polled_device(poll_dev);
 134        if (error)
 135                goto err_free_mem;
 136
 137        return 0;
 138
 139 err_free_mem:
 140        input_free_polled_device(poll_dev);
 141        kfree(bdev);
 142        dev_set_drvdata(&pdev->dev, NULL);
 143        return error;
 144}
 145
 146static int __devexit sgi_buttons_remove(struct platform_device *pdev)
 147{
 148        struct device *dev = &pdev->dev;
 149        struct buttons_dev *bdev = dev_get_drvdata(dev);
 150
 151        input_unregister_polled_device(bdev->poll_dev);
 152        input_free_polled_device(bdev->poll_dev);
 153        kfree(bdev);
 154        dev_set_drvdata(dev, NULL);
 155
 156        return 0;
 157}
 158
 159static struct platform_driver sgi_buttons_driver = {
 160        .probe  = sgi_buttons_probe,
 161        .remove = __devexit_p(sgi_buttons_remove),
 162        .driver = {
 163                .name   = "sgibtns",
 164                .owner  = THIS_MODULE,
 165        },
 166};
 167
 168static int __init sgi_buttons_init(void)
 169{
 170        return platform_driver_register(&sgi_buttons_driver);
 171}
 172
 173static void __exit sgi_buttons_exit(void)
 174{
 175        platform_driver_unregister(&sgi_buttons_driver);
 176}
 177
 178MODULE_LICENSE("GPL");
 179module_init(sgi_buttons_init);
 180module_exit(sgi_buttons_exit);
 181