drivers/input/keyboard/omap-keypad.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * linux/drivers/input/keyboard/omap-keypad.c
   4  *
   5  * OMAP Keypad Driver
   6  *
   7  * Copyright (C) 2003 Nokia Corporation
   8  * Written by Timo Teräs <ext-timo.teras@nokia.com>
   9  *
  10  * Added support for H2 & H3 Keypad
  11  * Copyright (C) 2004 Texas Instruments
  12  */
  13
  14 #include <linux/module.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/types.h>
  17 #include <linux/input.h>
  18 #include <linux/kernel.h>
  19 #include <linux/delay.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/mutex.h>
  22 #include <linux/errno.h>
  23 #include <linux/slab.h>
  24 #include <linux/gpio.h>
  25 #include <linux/platform_data/gpio-omap.h>
  26 #include <linux/platform_data/keypad-omap.h>
  27 #include <linux/soc/ti/omap1-io.h>
  28
  29 #undef NEW_BOARD_LEARNING_MODE
  30
  31 static void omap_kp_tasklet(unsigned long);
  32 static void omap_kp_timer(struct timer_list *);
  33
  34 static unsigned char keypad_state[8];
  35 static DEFINE_MUTEX(kp_enable_mutex);
  36 static int kp_enable = 1;
  37 static int kp_cur_group = -1;
  38
  39 struct omap_kp {
  40         struct input_dev *input;
  41         struct timer_list timer;
  42         int irq;
  43         unsigned int rows;
  44         unsigned int cols;
  45         unsigned long delay;
  46         unsigned int debounce;
  47         unsigned short keymap[];
  48 };
  49
  50 static DECLARE_TASKLET_DISABLED_OLD(kp_tasklet, omap_kp_tasklet);
  51
  52 static unsigned int *row_gpios;
  53 static unsigned int *col_gpios;
  54
  55 static irqreturn_t omap_kp_interrupt(int irq, void *dev_id)
  56 {
  57         /* disable keyboard interrupt and schedule for handling */
  58         omap_writew(1, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
  59
  60         tasklet_schedule(&kp_tasklet);
  61
  62         return IRQ_HANDLED;
  63 }
  64
  65 static void omap_kp_timer(struct timer_list *unused)
  66 {
  67         tasklet_schedule(&kp_tasklet);
  68 }
  69
  70 static void omap_kp_scan_keypad(struct omap_kp *omap_kp, unsigned char *state)
  71 {
  72         int col = 0;
  73
  74         /* disable keyboard interrupt and schedule for handling */
  75         omap_writew(1, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
  76
  77         /* read the keypad status */
  78         omap_writew(0xff, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBC);
  79         for (col = 0; col < omap_kp->cols; col++) {
  80                 omap_writew(~(1 << col) & 0xff,
  81                             OMAP1_MPUIO_BASE + OMAP_MPUIO_KBC);
  82
  83                 udelay(omap_kp->delay);
  84
  85                 state[col] = ~omap_readw(OMAP1_MPUIO_BASE +
  86                                          OMAP_MPUIO_KBR_LATCH) & 0xff;
  87         }
  88         omap_writew(0x00, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBC);
  89         udelay(2);
  90 }
  91
  92 static void omap_kp_tasklet(unsigned long data)
  93 {
  94         struct omap_kp *omap_kp_data = (struct omap_kp *) data;
  95         unsigned short *keycodes = omap_kp_data->input->keycode;
  96         unsigned int row_shift = get_count_order(omap_kp_data->cols);
  97         unsigned char new_state[8], changed, key_down = 0;
  98         int col, row;
  99
 100         /* check for any changes */
 101         omap_kp_scan_keypad(omap_kp_data, new_state);
 102
 103         /* check for changes and print those */
 104         for (col = 0; col < omap_kp_data->cols; col++) {
 105                 changed = new_state[col] ^ keypad_state[col];
 106                 key_down |= new_state[col];
 107                 if (changed == 0)
 108                         continue;
 109
 110                 for (row = 0; row < omap_kp_data->rows; row++) {
 111                         int key;
 112                         if (!(changed & (1 << row)))
 113                                 continue;
 114 #ifdef NEW_BOARD_LEARNING_MODE
 115                         printk(KERN_INFO "omap-keypad: key %d-%d %s\n", col,
 116                                row, (new_state[col] & (1 << row)) ?
 117                                "pressed" : "released");
 118 #else
 119                         key = keycodes[MATRIX_SCAN_CODE(row, col, row_shift)];
 120
 121                         if (!(kp_cur_group == (key & GROUP_MASK) ||
 122                               kp_cur_group == -1))
 123                                 continue;
 124
 125                         kp_cur_group = key & GROUP_MASK;
 126                         input_report_key(omap_kp_data->input, key & ~GROUP_MASK,
 127                                          new_state[col] & (1 << row));
 128 #endif
 129                 }
 130         }
 131         input_sync(omap_kp_data->input);
 132         memcpy(keypad_state, new_state, sizeof(keypad_state));
 133
 134         if (key_down) {
 135                 /* some key is pressed - keep irq disabled and use timer
 136                  * to poll the keypad */
 137                 mod_timer(&omap_kp_data->timer, jiffies + HZ / 20);
 138         } else {
 139                 /* enable interrupts */
 140                 omap_writew(0, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
 141                 kp_cur_group = -1;
 142         }
 143 }
 144
 145 static ssize_t omap_kp_enable_show(struct device *dev,
 146                                    struct device_attribute *attr, char *buf)
 147 {
 148         return sprintf(buf, "%u\n", kp_enable);
 149 }
 150
 151 static ssize_t omap_kp_enable_store(struct device *dev, struct device_attribute *attr,
 152                                     const char *buf, size_t count)
 153 {
 154         struct omap_kp *omap_kp = dev_get_drvdata(dev);
 155         int state;
 156
 157         if (sscanf(buf, "%u", &state) != 1)
 158                 return -EINVAL;
 159
 160         if ((state != 1) && (state != 0))
 161                 return -EINVAL;
 162
 163         mutex_lock(&kp_enable_mutex);
 164         if (state != kp_enable) {
 165                 if (state)
 166                         enable_irq(omap_kp->irq);
 167                 else
 168                         disable_irq(omap_kp->irq);
 169                 kp_enable = state;
 170         }
 171         mutex_unlock(&kp_enable_mutex);
 172
 173         return strnlen(buf, count);
 174 }
 175
 176 static DEVICE_ATTR(enable, S_IRUGO | S_IWUSR, omap_kp_enable_show, omap_kp_enable_store);
 177
 178 static int omap_kp_probe(struct platform_device *pdev)
 179 {
 180         struct omap_kp *omap_kp;
 181         struct input_dev *input_dev;
 182         struct omap_kp_platform_data *pdata = dev_get_platdata(&pdev->dev);
 183         int i, col_idx, row_idx, ret;
 184         unsigned int row_shift, keycodemax;
 185
 186         if (!pdata->rows || !pdata->cols || !pdata->keymap_data) {
 187                 printk(KERN_ERR "No rows, cols or keymap_data from pdata\n");
 188                 return -EINVAL;
 189         }
 190
 191         row_shift = get_count_order(pdata->cols);
 192         keycodemax = pdata->rows << row_shift;
 193
 194         omap_kp = kzalloc(struct_size(omap_kp, keymap, keycodemax), GFP_KERNEL);
 195         input_dev = input_allocate_device();
 196         if (!omap_kp || !input_dev) {
 197                 kfree(omap_kp);
 198                 input_free_device(input_dev);
 199                 return -ENOMEM;
 200         }
 201
 202         platform_set_drvdata(pdev, omap_kp);
 203
 204         omap_kp->input = input_dev;
 205
 206         /* Disable the interrupt for the MPUIO keyboard */
 207         omap_writew(1, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
 208
 209         if (pdata->delay)
 210                 omap_kp->delay = pdata->delay;
 211
 212         if (pdata->row_gpios && pdata->col_gpios) {
 213                 row_gpios = pdata->row_gpios;
 214                 col_gpios = pdata->col_gpios;
 215         }
 216
 217         omap_kp->rows = pdata->rows;
 218         omap_kp->cols = pdata->cols;
 219
 220         col_idx = 0;
 221         row_idx = 0;
 222
 223         timer_setup(&omap_kp->timer, omap_kp_timer, 0);
 224
 225         /* get the irq and init timer*/
 226         kp_tasklet.data = (unsigned long) omap_kp;
 227         tasklet_enable(&kp_tasklet);
 228
 229         ret = device_create_file(&pdev->dev, &dev_attr_enable);
 230         if (ret < 0)
 231                 goto err2;
 232
 233         /* setup input device */
 234         input_dev->name = "omap-keypad";
 235         input_dev->phys = "omap-keypad/input0";
 236         input_dev->dev.parent = &pdev->dev;
 237
 238         input_dev->id.bustype = BUS_HOST;
 239         input_dev->id.vendor = 0x0001;
 240         input_dev->id.product = 0x0001;
 241         input_dev->id.version = 0x0100;
 242
 243         if (pdata->rep)
 244                 __set_bit(EV_REP, input_dev->evbit);
 245
 246         ret = matrix_keypad_build_keymap(pdata->keymap_data, NULL,
 247                                          pdata->rows, pdata->cols,
 248                                          omap_kp->keymap, input_dev);
 249         if (ret < 0)
 250                 goto err3;
 251
 252         ret = input_register_device(omap_kp->input);
 253         if (ret < 0) {
 254                 printk(KERN_ERR "Unable to register omap-keypad input device\n");
 255                 goto err3;
 256         }
 257
 258         if (pdata->dbounce)
 259                 omap_writew(0xff, OMAP1_MPUIO_BASE + OMAP_MPUIO_GPIO_DEBOUNCING);
 260
 261         /* scan current status and enable interrupt */
 262         omap_kp_scan_keypad(omap_kp, keypad_state);
 263         omap_kp->irq = platform_get_irq(pdev, 0);
 264         if (omap_kp->irq >= 0) {
 265                 if (request_irq(omap_kp->irq, omap_kp_interrupt, 0,
 266                                 "omap-keypad", omap_kp) < 0)
 267                         goto err4;
 268         }
 269         omap_writew(0, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
 270
 271         return 0;
 272
 273 err4:
 274         input_unregister_device(omap_kp->input);
 275         input_dev = NULL;
 276 err3:
 277         device_remove_file(&pdev->dev, &dev_attr_enable);
 278 err2:
 279         for (i = row_idx - 1; i >= 0; i--)
 280                 gpio_free(row_gpios[i]);
 281         for (i = col_idx - 1; i >= 0; i--)
 282                 gpio_free(col_gpios[i]);
 283
 284         kfree(omap_kp);
 285         input_free_device(input_dev);
 286
 287         return -EINVAL;
 288 }
 289
 290 static int omap_kp_remove(struct platform_device *pdev)
 291 {
 292         struct omap_kp *omap_kp = platform_get_drvdata(pdev);
 293
 294         /* disable keypad interrupt handling */
 295         tasklet_disable(&kp_tasklet);
 296         omap_writew(1, OMAP1_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
 297         free_irq(omap_kp->irq, omap_kp);
 298
 299         del_timer_sync(&omap_kp->timer);
 300         tasklet_kill(&kp_tasklet);
 301
 302         /* unregister everything */
 303         input_unregister_device(omap_kp->input);
 304
 305         kfree(omap_kp);
 306
 307         return 0;
 308 }
 309
 310 static struct platform_driver omap_kp_driver = {
 311         .probe          = omap_kp_probe,
 312         .remove         = omap_kp_remove,
 313         .driver         = {
 314                 .name   = "omap-keypad",
 315         },
 316 };
 317 module_platform_driver(omap_kp_driver);
 318
 319 MODULE_AUTHOR("Timo Teräs");
 320 MODULE_DESCRIPTION("OMAP Keypad Driver");
 321 MODULE_LICENSE("GPL");
 322 MODULE_ALIAS("platform:omap-keypad");