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