drivers/input/keyboard/locomokbd.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * LoCoMo keyboard driver for Linux-based ARM PDAs:
   4  *      - SHARP Zaurus Collie (SL-5500)
   5  *      - SHARP Zaurus Poodle (SL-5600)
   6  *
   7  * Copyright (c) 2005 John Lenz
   8  * Based on from xtkbd.c
   9  */
  10
  11 #include <linux/slab.h>
  12 #include <linux/module.h>
  13 #include <linux/init.h>
  14 #include <linux/input.h>
  15 #include <linux/delay.h>
  16 #include <linux/device.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/ioport.h>
  19
  20 #include <asm/hardware/locomo.h>
  21 #include <asm/irq.h>
  22
  23 MODULE_AUTHOR("John Lenz <lenz@cs.wisc.edu>");
  24 MODULE_DESCRIPTION("LoCoMo keyboard driver");
  25 MODULE_LICENSE("GPL");
  26
  27 #define LOCOMOKBD_NUMKEYS       128
  28
  29 #define KEY_ACTIVITY            KEY_F16
  30 #define KEY_CONTACT             KEY_F18
  31 #define KEY_CENTER              KEY_F15
  32
  33 static const unsigned char
  34 locomokbd_keycode[LOCOMOKBD_NUMKEYS] = {
  35         0, KEY_ESC, KEY_ACTIVITY, 0, 0, 0, 0, 0, 0, 0,                          /* 0 - 9 */
  36         0, 0, 0, 0, 0, 0, 0, KEY_MENU, KEY_HOME, KEY_CONTACT,                   /* 10 - 19 */
  37         0, 0, 0, 0, 0, 0, 0, 0, 0, 0,                                           /* 20 - 29 */
  38         0, 0, 0, KEY_CENTER, 0, KEY_MAIL, 0, 0, 0, 0,                           /* 30 - 39 */
  39         0, 0, 0, 0, 0, 0, 0, 0, 0, KEY_RIGHT,                                   /* 40 - 49 */
  40         KEY_UP, KEY_LEFT, 0, 0, KEY_P, 0, KEY_O, KEY_I, KEY_Y, KEY_T,           /* 50 - 59 */
  41         KEY_E, KEY_W, 0, 0, 0, 0, KEY_DOWN, KEY_ENTER, 0, 0,                    /* 60 - 69 */
  42         KEY_BACKSPACE, 0, KEY_L, KEY_U, KEY_H, KEY_R, KEY_D, KEY_Q, 0, 0,       /* 70 - 79 */
  43         0, 0, 0, 0, 0, 0, KEY_ENTER, KEY_RIGHTSHIFT, KEY_K, KEY_J,              /* 80 - 89 */
  44         KEY_G, KEY_F, KEY_X, KEY_S, 0, 0, 0, 0, 0, 0,                           /* 90 - 99 */
  45         0, 0, KEY_DOT, 0, KEY_COMMA, KEY_N, KEY_B, KEY_C, KEY_Z, KEY_A,         /* 100 - 109 */
  46         KEY_LEFTSHIFT, KEY_TAB, KEY_LEFTCTRL, 0, 0, 0, 0, 0, 0, 0,              /* 110 - 119 */
  47         KEY_M, KEY_SPACE, KEY_V, KEY_APOSTROPHE, KEY_SLASH, 0, 0, 0             /* 120 - 128 */
  48 };
  49
  50 #define KB_ROWS                 16
  51 #define KB_COLS                 8
  52 #define KB_ROWMASK(r)           (1 << (r))
  53 #define SCANCODE(c,r)           ( ((c)<<4) + (r) + 1 )
  54
  55 #define KB_DELAY                8
  56 #define SCAN_INTERVAL           (HZ/10)
  57
  58 struct locomokbd {
  59         unsigned char keycode[LOCOMOKBD_NUMKEYS];
  60         struct input_dev *input;
  61         char phys[32];
  62
  63         unsigned long base;
  64         spinlock_t lock;
  65
  66         struct timer_list timer;
  67         unsigned long suspend_jiffies;
  68         unsigned int count_cancel;
  69 };
  70
  71 /* helper functions for reading the keyboard matrix */
  72 static inline void locomokbd_charge_all(unsigned long membase)
  73 {
  74         locomo_writel(0x00FF, membase + LOCOMO_KSC);
  75 }
  76
  77 static inline void locomokbd_activate_all(unsigned long membase)
  78 {
  79         unsigned long r;
  80
  81         locomo_writel(0, membase + LOCOMO_KSC);
  82         r = locomo_readl(membase + LOCOMO_KIC);
  83         r &= 0xFEFF;
  84         locomo_writel(r, membase + LOCOMO_KIC);
  85 }
  86
  87 static inline void locomokbd_activate_col(unsigned long membase, int col)
  88 {
  89         unsigned short nset;
  90         unsigned short nbset;
  91
  92         nset = 0xFF & ~(1 << col);
  93         nbset = (nset << 8) + nset;
  94         locomo_writel(nbset, membase + LOCOMO_KSC);
  95 }
  96
  97 static inline void locomokbd_reset_col(unsigned long membase, int col)
  98 {
  99         unsigned short nbset;
 100
 101         nbset = ((0xFF & ~(1 << col)) << 8) + 0xFF;
 102         locomo_writel(nbset, membase + LOCOMO_KSC);
 103 }
 104
 105 /*
 106  * The LoCoMo keyboard only generates interrupts when a key is pressed.
 107  * So when a key is pressed, we enable a timer.  This timer scans the
 108  * keyboard, and this is how we detect when the key is released.
 109  */
 110
 111 /* Scan the hardware keyboard and push any changes up through the input layer */
 112 static void locomokbd_scankeyboard(struct locomokbd *locomokbd)
 113 {
 114         unsigned int row, col, rowd;
 115         unsigned long flags;
 116         unsigned int num_pressed;
 117         unsigned long membase = locomokbd->base;
 118
 119         spin_lock_irqsave(&locomokbd->lock, flags);
 120
 121         locomokbd_charge_all(membase);
 122
 123         num_pressed = 0;
 124         for (col = 0; col < KB_COLS; col++) {
 125
 126                 locomokbd_activate_col(membase, col);
 127                 udelay(KB_DELAY);
 128
 129                 rowd = ~locomo_readl(membase + LOCOMO_KIB);
 130                 for (row = 0; row < KB_ROWS; row++) {
 131                         unsigned int scancode, pressed, key;
 132
 133                         scancode = SCANCODE(col, row);
 134                         pressed = rowd & KB_ROWMASK(row);
 135                         key = locomokbd->keycode[scancode];
 136
 137                         input_report_key(locomokbd->input, key, pressed);
 138                         if (likely(!pressed))
 139                                 continue;
 140
 141                         num_pressed++;
 142
 143                         /* The "Cancel/ESC" key is labeled "On/Off" on
 144                          * Collie and Poodle and should suspend the device
 145                          * if it was pressed for more than a second. */
 146                         if (unlikely(key == KEY_ESC)) {
 147                                 if (!time_after(jiffies,
 148                                         locomokbd->suspend_jiffies + HZ))
 149                                         continue;
 150                                 if (locomokbd->count_cancel++
 151                                         != (HZ/SCAN_INTERVAL + 1))
 152                                         continue;
 153                                 input_event(locomokbd->input, EV_PWR,
 154                                         KEY_SUSPEND, 1);
 155                                 locomokbd->suspend_jiffies = jiffies;
 156                         } else
 157                                 locomokbd->count_cancel = 0;
 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         else
 169                 locomokbd->count_cancel = 0;
 170
 171         spin_unlock_irqrestore(&locomokbd->lock, flags);
 172 }
 173
 174 /*
 175  * LoCoMo keyboard interrupt handler.
 176  */
 177 static irqreturn_t locomokbd_interrupt(int irq, void *dev_id)
 178 {
 179         struct locomokbd *locomokbd = dev_id;
 180         u16 r;
 181
 182         r = locomo_readl(locomokbd->base + LOCOMO_KIC);
 183         if ((r & 0x0001) == 0)
 184                 return IRQ_HANDLED;
 185
 186         locomo_writel(r & ~0x0100, locomokbd->base + LOCOMO_KIC); /* Ack */
 187
 188         /** wait chattering delay **/
 189         udelay(100);
 190
 191         locomokbd_scankeyboard(locomokbd);
 192         return IRQ_HANDLED;
 193 }
 194
 195 /*
 196  * LoCoMo timer checking for released keys
 197  */
 198 static void locomokbd_timer_callback(struct timer_list *t)
 199 {
 200         struct locomokbd *locomokbd = from_timer(locomokbd, t, timer);
 201
 202         locomokbd_scankeyboard(locomokbd);
 203 }
 204
 205 static int locomokbd_open(struct input_dev *dev)
 206 {
 207         struct locomokbd *locomokbd = input_get_drvdata(dev);
 208         u16 r;
 209
 210         r = locomo_readl(locomokbd->base + LOCOMO_KIC) | 0x0010;
 211         locomo_writel(r, locomokbd->base + LOCOMO_KIC);
 212         return 0;
 213 }
 214
 215 static void locomokbd_close(struct input_dev *dev)
 216 {
 217         struct locomokbd *locomokbd = input_get_drvdata(dev);
 218         u16 r;
 219
 220         r = locomo_readl(locomokbd->base + LOCOMO_KIC) & ~0x0010;
 221         locomo_writel(r, locomokbd->base + LOCOMO_KIC);
 222 }
 223
 224 static int locomokbd_probe(struct locomo_dev *dev)
 225 {
 226         struct locomokbd *locomokbd;
 227         struct input_dev *input_dev;
 228         int i, err;
 229
 230         locomokbd = kzalloc(sizeof(struct locomokbd), GFP_KERNEL);
 231         input_dev = input_allocate_device();
 232         if (!locomokbd || !input_dev) {
 233                 err = -ENOMEM;
 234                 goto err_free_mem;
 235         }
 236
 237         /* try and claim memory region */
 238         if (!request_mem_region((unsigned long) dev->mapbase,
 239                                 dev->length,
 240                                 LOCOMO_DRIVER_NAME(dev))) {
 241                 err = -EBUSY;
 242                 printk(KERN_ERR "locomokbd: Can't acquire access to io memory for keyboard\n");
 243                 goto err_free_mem;
 244         }
 245
 246         locomo_set_drvdata(dev, locomokbd);
 247
 248         locomokbd->base = (unsigned long) dev->mapbase;
 249
 250         spin_lock_init(&locomokbd->lock);
 251
 252         timer_setup(&locomokbd->timer, locomokbd_timer_callback, 0);
 253
 254         locomokbd->suspend_jiffies = jiffies;
 255
 256         locomokbd->input = input_dev;
 257         strcpy(locomokbd->phys, "locomokbd/input0");
 258
 259         input_dev->name = "LoCoMo keyboard";
 260         input_dev->phys = locomokbd->phys;
 261         input_dev->id.bustype = BUS_HOST;
 262         input_dev->id.vendor = 0x0001;
 263         input_dev->id.product = 0x0001;
 264         input_dev->id.version = 0x0100;
 265         input_dev->open = locomokbd_open;
 266         input_dev->close = locomokbd_close;
 267         input_dev->dev.parent = &dev->dev;
 268
 269         input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP) |
 270                                 BIT_MASK(EV_PWR);
 271         input_dev->keycode = locomokbd->keycode;
 272         input_dev->keycodesize = sizeof(locomokbd_keycode[0]);
 273         input_dev->keycodemax = ARRAY_SIZE(locomokbd_keycode);
 274
 275         input_set_drvdata(input_dev, locomokbd);
 276
 277         memcpy(locomokbd->keycode, locomokbd_keycode, sizeof(locomokbd->keycode));
 278         for (i = 0; i < LOCOMOKBD_NUMKEYS; i++)
 279                 set_bit(locomokbd->keycode[i], input_dev->keybit);
 280         clear_bit(0, input_dev->keybit);
 281
 282         /* attempt to get the interrupt */
 283         err = request_irq(dev->irq[0], locomokbd_interrupt, 0, "locomokbd", locomokbd);
 284         if (err) {
 285                 printk(KERN_ERR "locomokbd: Can't get irq for keyboard\n");
 286                 goto err_release_region;
 287         }
 288
 289         err = input_register_device(locomokbd->input);
 290         if (err)
 291                 goto err_free_irq;
 292
 293         return 0;
 294
 295  err_free_irq:
 296         free_irq(dev->irq[0], locomokbd);
 297  err_release_region:
 298         release_mem_region((unsigned long) dev->mapbase, dev->length);
 299         locomo_set_drvdata(dev, NULL);
 300  err_free_mem:
 301         input_free_device(input_dev);
 302         kfree(locomokbd);
 303
 304         return err;
 305 }
 306
 307 static int locomokbd_remove(struct locomo_dev *dev)
 308 {
 309         struct locomokbd *locomokbd = locomo_get_drvdata(dev);
 310
 311         free_irq(dev->irq[0], locomokbd);
 312
 313         del_timer_sync(&locomokbd->timer);
 314
 315         input_unregister_device(locomokbd->input);
 316         locomo_set_drvdata(dev, NULL);
 317
 318         release_mem_region((unsigned long) dev->mapbase, dev->length);
 319
 320         kfree(locomokbd);
 321
 322         return 0;
 323 }
 324
 325 static struct locomo_driver keyboard_driver = {
 326         .drv = {
 327                 .name = "locomokbd"
 328         },
 329         .devid  = LOCOMO_DEVID_KEYBOARD,
 330         .probe  = locomokbd_probe,
 331         .remove = locomokbd_remove,
 332 };
 333
 334 static int __init locomokbd_init(void)
 335 {
 336         return locomo_driver_register(&keyboard_driver);
 337 }
 338
 339 static void __exit locomokbd_exit(void)
 340 {
 341         locomo_driver_unregister(&keyboard_driver);
 342 }
 343
 344 module_init(locomokbd_init);
 345 module_exit(locomokbd_exit);