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 int num_pressed;
 116         unsigned long membase = locomokbd->base;
 117
 118         guard(spinlock_irqsave)(&locomokbd->lock);
 119
 120         locomokbd_charge_all(membase);
 121
 122         num_pressed = 0;
 123         for (col = 0; col < KB_COLS; col++) {
 124
 125                 locomokbd_activate_col(membase, col);
 126                 udelay(KB_DELAY);
 127
 128                 rowd = ~locomo_readl(membase + LOCOMO_KIB);
 129                 for (row = 0; row < KB_ROWS; row++) {
 130                         unsigned int scancode, pressed, key;
 131
 132                         scancode = SCANCODE(col, row);
 133                         pressed = rowd & KB_ROWMASK(row);
 134                         key = locomokbd->keycode[scancode];
 135
 136                         input_report_key(locomokbd->input, key, pressed);
 137                         if (likely(!pressed))
 138                                 continue;
 139
 140                         num_pressed++;
 141
 142                         /* The "Cancel/ESC" key is labeled "On/Off" on
 143                          * Collie and Poodle and should suspend the device
 144                          * if it was pressed for more than a second. */
 145                         if (unlikely(key == KEY_ESC)) {
 146                                 if (!time_after(jiffies,
 147                                         locomokbd->suspend_jiffies + HZ))
 148                                         continue;
 149                                 if (locomokbd->count_cancel++
 150                                         != (HZ/SCAN_INTERVAL + 1))
 151                                         continue;
 152                                 input_event(locomokbd->input, EV_PWR,
 153                                         KEY_SUSPEND, 1);
 154                                 locomokbd->suspend_jiffies = jiffies;
 155                         } else
 156                                 locomokbd->count_cancel = 0;
 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         else
 168                 locomokbd->count_cancel = 0;
 169 }
 170
 171 /*
 172  * LoCoMo keyboard interrupt handler.
 173  */
 174 static irqreturn_t locomokbd_interrupt(int irq, void *dev_id)
 175 {
 176         struct locomokbd *locomokbd = dev_id;
 177         u16 r;
 178
 179         r = locomo_readl(locomokbd->base + LOCOMO_KIC);
 180         if ((r & 0x0001) == 0)
 181                 return IRQ_HANDLED;
 182
 183         locomo_writel(r & ~0x0100, locomokbd->base + LOCOMO_KIC); /* Ack */
 184
 185         /** wait chattering delay **/
 186         udelay(100);
 187
 188         locomokbd_scankeyboard(locomokbd);
 189         return IRQ_HANDLED;
 190 }
 191
 192 /*
 193  * LoCoMo timer checking for released keys
 194  */
 195 static void locomokbd_timer_callback(struct timer_list *t)
 196 {
 197         struct locomokbd *locomokbd = from_timer(locomokbd, t, timer);
 198
 199         locomokbd_scankeyboard(locomokbd);
 200 }
 201
 202 static int locomokbd_open(struct input_dev *dev)
 203 {
 204         struct locomokbd *locomokbd = input_get_drvdata(dev);
 205         u16 r;
 206
 207         r = locomo_readl(locomokbd->base + LOCOMO_KIC) | 0x0010;
 208         locomo_writel(r, locomokbd->base + LOCOMO_KIC);
 209         return 0;
 210 }
 211
 212 static void locomokbd_close(struct input_dev *dev)
 213 {
 214         struct locomokbd *locomokbd = input_get_drvdata(dev);
 215         u16 r;
 216
 217         r = locomo_readl(locomokbd->base + LOCOMO_KIC) & ~0x0010;
 218         locomo_writel(r, locomokbd->base + LOCOMO_KIC);
 219 }
 220
 221 static int locomokbd_probe(struct locomo_dev *dev)
 222 {
 223         struct locomokbd *locomokbd;
 224         struct input_dev *input_dev;
 225         int i, err;
 226
 227         locomokbd = kzalloc(sizeof(*locomokbd), GFP_KERNEL);
 228         input_dev = input_allocate_device();
 229         if (!locomokbd || !input_dev) {
 230                 err = -ENOMEM;
 231                 goto err_free_mem;
 232         }
 233
 234         /* try and claim memory region */
 235         if (!request_mem_region((unsigned long) dev->mapbase,
 236                                 dev->length,
 237                                 LOCOMO_DRIVER_NAME(dev))) {
 238                 err = -EBUSY;
 239                 printk(KERN_ERR "locomokbd: Can't acquire access to io memory for keyboard\n");
 240                 goto err_free_mem;
 241         }
 242
 243         locomo_set_drvdata(dev, locomokbd);
 244
 245         locomokbd->base = (unsigned long) dev->mapbase;
 246
 247         spin_lock_init(&locomokbd->lock);
 248
 249         timer_setup(&locomokbd->timer, locomokbd_timer_callback, 0);
 250
 251         locomokbd->suspend_jiffies = jiffies;
 252
 253         locomokbd->input = input_dev;
 254         strcpy(locomokbd->phys, "locomokbd/input0");
 255
 256         input_dev->name = "LoCoMo keyboard";
 257         input_dev->phys = locomokbd->phys;
 258         input_dev->id.bustype = BUS_HOST;
 259         input_dev->id.vendor = 0x0001;
 260         input_dev->id.product = 0x0001;
 261         input_dev->id.version = 0x0100;
 262         input_dev->open = locomokbd_open;
 263         input_dev->close = locomokbd_close;
 264         input_dev->dev.parent = &dev->dev;
 265
 266         input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP) |
 267                                 BIT_MASK(EV_PWR);
 268         input_dev->keycode = locomokbd->keycode;
 269         input_dev->keycodesize = sizeof(locomokbd_keycode[0]);
 270         input_dev->keycodemax = ARRAY_SIZE(locomokbd_keycode);
 271
 272         input_set_drvdata(input_dev, locomokbd);
 273
 274         memcpy(locomokbd->keycode, locomokbd_keycode, sizeof(locomokbd->keycode));
 275         for (i = 0; i < LOCOMOKBD_NUMKEYS; i++)
 276                 set_bit(locomokbd->keycode[i], input_dev->keybit);
 277         clear_bit(0, input_dev->keybit);
 278
 279         /* attempt to get the interrupt */
 280         err = request_irq(dev->irq[0], locomokbd_interrupt, 0, "locomokbd", locomokbd);
 281         if (err) {
 282                 printk(KERN_ERR "locomokbd: Can't get irq for keyboard\n");
 283                 goto err_release_region;
 284         }
 285
 286         err = input_register_device(locomokbd->input);
 287         if (err)
 288                 goto err_free_irq;
 289
 290         return 0;
 291
 292  err_free_irq:
 293         free_irq(dev->irq[0], locomokbd);
 294  err_release_region:
 295         release_mem_region((unsigned long) dev->mapbase, dev->length);
 296         locomo_set_drvdata(dev, NULL);
 297  err_free_mem:
 298         input_free_device(input_dev);
 299         kfree(locomokbd);
 300
 301         return err;
 302 }
 303
 304 static void locomokbd_remove(struct locomo_dev *dev)
 305 {
 306         struct locomokbd *locomokbd = locomo_get_drvdata(dev);
 307
 308         free_irq(dev->irq[0], locomokbd);
 309
 310         timer_shutdown_sync(&locomokbd->timer);
 311
 312         input_unregister_device(locomokbd->input);
 313         locomo_set_drvdata(dev, NULL);
 314
 315         release_mem_region((unsigned long) dev->mapbase, dev->length);
 316
 317         kfree(locomokbd);
 318 }
 319
 320 static struct locomo_driver keyboard_driver = {
 321         .drv = {
 322                 .name = "locomokbd"
 323         },
 324         .devid  = LOCOMO_DEVID_KEYBOARD,
 325         .probe  = locomokbd_probe,
 326         .remove = locomokbd_remove,
 327 };
 328
 329 static int __init locomokbd_init(void)
 330 {
 331         return locomo_driver_register(&keyboard_driver);
 332 }
 333
 334 static void __exit locomokbd_exit(void)
 335 {
 336         locomo_driver_unregister(&keyboard_driver);
 337 }
 338
 339 module_init(locomokbd_init);
 340 module_exit(locomokbd_exit);