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