drivers/input/keyboard/locomokbd.c

   1 /*
   2  *  Copyright (c) 2005 John Lenz
   3  *
   4  * Based on from xtkbd.c
   5  */
   6
   7 /*
   8  * LoCoMo keyboard driver for Linux/ARM
   9  */
  10
  11 /*
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  25  *
  26  */
  27
  28 #include <linux/config.h>
  29 #include <linux/slab.h>
  30 #include <linux/module.h>
  31 #include <linux/init.h>
  32 #include <linux/input.h>
  33 #include <linux/delay.h>
  34 #include <linux/device.h>
  35 #include <linux/interrupt.h>
  36 #include <linux/ioport.h>
  37
  38 #include <asm/hardware/locomo.h>
  39 #include <asm/irq.h>
  40
  41 MODULE_AUTHOR("John Lenz <lenz@cs.wisc.edu>");
  42 MODULE_DESCRIPTION("LoCoMo keyboard driver");
  43 MODULE_LICENSE("GPL");
  44
  45 #define LOCOMOKBD_NUMKEYS       128
  46
  47 #define KEY_ACTIVITY            KEY_F16
  48 #define KEY_CONTACT             KEY_F18
  49 #define KEY_CENTER              KEY_F15
  50
  51 static unsigned char locomokbd_keycode[LOCOMOKBD_NUMKEYS] = {
  52         0, KEY_ESC, KEY_ACTIVITY, 0, 0, 0, 0, 0, 0, 0,                          /* 0 - 9 */
  53         0, 0, 0, 0, 0, 0, 0, KEY_MENU, KEY_HOME, KEY_CONTACT,                   /* 10 - 19 */
  54         0, 0, 0, 0, 0, 0, 0, 0, 0, 0,                                           /* 20 - 29 */
  55         0, 0, 0, KEY_CENTER, 0, KEY_MAIL, 0, 0, 0, 0,                           /* 30 - 39 */
  56         0, 0, 0, 0, 0, 0, 0, 0, 0, KEY_RIGHT,                                   /* 40 - 49 */
  57         KEY_UP, KEY_LEFT, 0, 0, KEY_P, 0, KEY_O, KEY_I, KEY_Y, KEY_T,           /* 50 - 59 */
  58         KEY_E, KEY_W, 0, 0, 0, 0, KEY_DOWN, KEY_ENTER, 0, 0,                    /* 60 - 69 */
  59         KEY_BACKSPACE, 0, KEY_L, KEY_U, KEY_H, KEY_R, KEY_D, KEY_Q, 0, 0,       /* 70 - 79 */
  60         0, 0, 0, 0, 0, 0, KEY_ENTER, KEY_RIGHTSHIFT, KEY_K, KEY_J,              /* 80 - 89 */
  61         KEY_G, KEY_F, KEY_X, KEY_S, 0, 0, 0, 0, 0, 0,                           /* 90 - 99 */
  62         0, 0, KEY_DOT, 0, KEY_COMMA, KEY_N, KEY_B, KEY_C, KEY_Z, KEY_A,         /* 100 - 109 */
  63         KEY_LEFTSHIFT, KEY_TAB, KEY_LEFTCTRL, 0, 0, 0, 0, 0, 0, 0,              /* 110 - 119 */
  64         KEY_M, KEY_SPACE, KEY_V, KEY_APOSTROPHE, KEY_SLASH, 0, 0, 0             /* 120 - 128 */
  65 };
  66
  67 #define KB_ROWS                 16
  68 #define KB_COLS                 8
  69 #define KB_ROWMASK(r)           (1 << (r))
  70 #define SCANCODE(c,r)           ( ((c)<<4) + (r) + 1 )
  71 #define NR_SCANCODES            128
  72
  73 #define KB_DELAY                8
  74 #define SCAN_INTERVAL           (HZ/10)
  75 #define LOCOMOKBD_PRESSED       1
  76
  77 struct locomokbd {
  78         unsigned char keycode[LOCOMOKBD_NUMKEYS];
  79         struct input_dev *input;
  80         char phys[32];
  81
  82         struct locomo_dev *ldev;
  83         unsigned long base;
  84         spinlock_t lock;
  85
  86         struct timer_list timer;
  87 };
  88
  89 /* helper functions for reading the keyboard matrix */
  90 static inline void locomokbd_charge_all(unsigned long membase)
  91 {
  92         locomo_writel(0x00FF, membase + LOCOMO_KSC);
  93 }
  94
  95 static inline void locomokbd_activate_all(unsigned long membase)
  96 {
  97         unsigned long r;
  98
  99         locomo_writel(0, membase + LOCOMO_KSC);
 100         r = locomo_readl(membase + LOCOMO_KIC);
 101         r &= 0xFEFF;
 102         locomo_writel(r, membase + LOCOMO_KIC);
 103 }
 104
 105 static inline void locomokbd_activate_col(unsigned long membase, int col)
 106 {
 107         unsigned short nset;
 108         unsigned short nbset;
 109
 110         nset = 0xFF & ~(1 << col);
 111         nbset = (nset << 8) + nset;
 112         locomo_writel(nbset, membase + LOCOMO_KSC);
 113 }
 114
 115 static inline void locomokbd_reset_col(unsigned long membase, int col)
 116 {
 117         unsigned short nbset;
 118
 119         nbset = ((0xFF & ~(1 << col)) << 8) + 0xFF;
 120         locomo_writel(nbset, membase + LOCOMO_KSC);
 121 }
 122
 123 /*
 124  * The LoCoMo keyboard only generates interrupts when a key is pressed.
 125  * So when a key is pressed, we enable a timer.  This timer scans the
 126  * keyboard, and this is how we detect when the key is released.
 127  */
 128
 129 /* Scan the hardware keyboard and push any changes up through the input layer */
 130 static void locomokbd_scankeyboard(struct locomokbd *locomokbd, struct pt_regs *regs)
 131 {
 132         unsigned int row, col, rowd, scancode;
 133         unsigned long flags;
 134         unsigned int num_pressed;
 135         unsigned long membase = locomokbd->base;
 136
 137         spin_lock_irqsave(&locomokbd->lock, flags);
 138
 139         input_regs(locomokbd->input, regs);
 140
 141         locomokbd_charge_all(membase);
 142
 143         num_pressed = 0;
 144         for (col = 0; col < KB_COLS; col++) {
 145
 146                 locomokbd_activate_col(membase, col);
 147                 udelay(KB_DELAY);
 148
 149                 rowd = ~locomo_readl(membase + LOCOMO_KIB);
 150                 for (row = 0; row < KB_ROWS; row++) {
 151                         scancode = SCANCODE(col, row);
 152                         if (rowd & KB_ROWMASK(row)) {
 153                                 num_pressed += 1;
 154                                 input_report_key(locomokbd->input, locomokbd->keycode[scancode], 1);
 155                         } else {
 156                                 input_report_key(locomokbd->input, locomokbd->keycode[scancode], 0);
 157                         }
 158                 }
 159                 locomokbd_reset_col(membase, col);
 160         }
 161         locomokbd_activate_all(membase);
 162
 163         input_sync(locomokbd->input);
 164
 165         /* if any keys are pressed, enable the timer */
 166         if (num_pressed)
 167                 mod_timer(&locomokbd->timer, jiffies + SCAN_INTERVAL);
 168
 169         spin_unlock_irqrestore(&locomokbd->lock, flags);
 170 }
 171
 172 /*
 173  * LoCoMo keyboard interrupt handler.
 174  */
 175 static irqreturn_t locomokbd_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 176 {
 177         struct locomokbd *locomokbd = dev_id;
 178         /** wait chattering delay **/
 179         udelay(100);
 180
 181         locomokbd_scankeyboard(locomokbd, regs);
 182
 183         return IRQ_HANDLED;
 184 }
 185
 186 /*
 187  * LoCoMo timer checking for released keys
 188  */
 189 static void locomokbd_timer_callback(unsigned long data)
 190 {
 191         struct locomokbd *locomokbd = (struct locomokbd *) data;
 192         locomokbd_scankeyboard(locomokbd, NULL);
 193 }
 194
 195 static int locomokbd_probe(struct locomo_dev *dev)
 196 {
 197         struct locomokbd *locomokbd;
 198         struct input_dev *input_dev;
 199         int i, ret;
 200
 201         locomokbd = kzalloc(sizeof(struct locomokbd), GFP_KERNEL);
 202         input_dev = input_allocate_device();
 203         if (!locomokbd || !input_dev) {
 204                 ret = -ENOMEM;
 205                 goto free;
 206         }
 207
 208         /* try and claim memory region */
 209         if (!request_mem_region((unsigned long) dev->mapbase,
 210                                 dev->length,
 211                                 LOCOMO_DRIVER_NAME(dev))) {
 212                 ret = -EBUSY;
 213                 printk(KERN_ERR "locomokbd: Can't acquire access to io memory for keyboard\n");
 214                 goto free;
 215         }
 216
 217         locomokbd->ldev = dev;
 218         locomo_set_drvdata(dev, locomokbd);
 219
 220         locomokbd->base = (unsigned long) dev->mapbase;
 221
 222         spin_lock_init(&locomokbd->lock);
 223
 224         init_timer(&locomokbd->timer);
 225         locomokbd->timer.function = locomokbd_timer_callback;
 226         locomokbd->timer.data = (unsigned long) locomokbd;
 227
 228         locomokbd->input = input_dev;
 229         strcpy(locomokbd->phys, "locomokbd/input0");
 230
 231         input_dev->name = "LoCoMo keyboard";
 232         input_dev->phys = locomokbd->phys;
 233         input_dev->id.bustype = BUS_XTKBD;
 234         input_dev->id.vendor = 0x0001;
 235         input_dev->id.product = 0x0001;
 236         input_dev->id.version = 0x0100;
 237         input_dev->private = locomokbd;
 238
 239         input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_REP);
 240         input_dev->keycode = locomokbd->keycode;
 241         input_dev->keycodesize = sizeof(unsigned char);
 242         input_dev->keycodemax = ARRAY_SIZE(locomokbd_keycode);
 243
 244         memcpy(locomokbd->keycode, locomokbd_keycode, sizeof(locomokbd->keycode));
 245         for (i = 0; i < LOCOMOKBD_NUMKEYS; i++)
 246                 set_bit(locomokbd->keycode[i], input_dev->keybit);
 247         clear_bit(0, input_dev->keybit);
 248
 249         /* attempt to get the interrupt */
 250         ret = request_irq(dev->irq[0], locomokbd_interrupt, 0, "locomokbd", locomokbd);
 251         if (ret) {
 252                 printk(KERN_ERR "locomokbd: Can't get irq for keyboard\n");
 253                 goto out;
 254         }
 255
 256         input_register_device(locomokbd->input);
 257
 258         return 0;
 259
 260 out:
 261         release_mem_region((unsigned long) dev->mapbase, dev->length);
 262         locomo_set_drvdata(dev, NULL);
 263 free:
 264         input_free_device(input_dev);
 265         kfree(locomokbd);
 266
 267         return ret;
 268 }
 269
 270 static int locomokbd_remove(struct locomo_dev *dev)
 271 {
 272         struct locomokbd *locomokbd = locomo_get_drvdata(dev);
 273
 274         free_irq(dev->irq[0], locomokbd);
 275
 276         del_timer_sync(&locomokbd->timer);
 277
 278         input_unregister_device(locomokbd->input);
 279         locomo_set_drvdata(dev, NULL);
 280
 281         release_mem_region((unsigned long) dev->mapbase, dev->length);
 282
 283         kfree(locomokbd);
 284
 285         return 0;
 286 }
 287
 288 static struct locomo_driver keyboard_driver = {
 289         .drv = {
 290                 .name = "locomokbd"
 291         },
 292         .devid  = LOCOMO_DEVID_KEYBOARD,
 293         .probe  = locomokbd_probe,
 294         .remove = locomokbd_remove,
 295 };
 296
 297 static int __init locomokbd_init(void)
 298 {
 299         return locomo_driver_register(&keyboard_driver);
 300 }
 301
 302 static void __exit locomokbd_exit(void)
 303 {
 304         locomo_driver_unregister(&keyboard_driver);
 305 }
 306
 307 module_init(locomokbd_init);
 308 module_exit(locomokbd_exit);