drivers/input/keyboard/rk_keys.c

   1 /*
   2  * Driver for keys on GPIO lines capable of generating interrupts.
   3  *
   4  * Copyright 2005 Phil Blundell
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 #include <linux/module.h>
  12 #include <linux/init.h>
  13 #include <linux/fs.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/irq.h>
  16 #include <linux/sched.h>
  17 #include <linux/pm.h>
  18 #include <linux/sysctl.h>
  19 #include <linux/proc_fs.h>
  20 #include <linux/delay.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/input.h>
  23 #include <linux/adc.h>
  24 #include <linux/slab.h>
  25
  26 #include <linux/iio/iio.h>
  27 #include <linux/iio/machine.h>
  28 #include <linux/iio/driver.h>
  29 #include <linux/iio/consumer.h>
  30
  31 #include <asm/gpio.h>
  32 #include <linux/of.h>
  33 #include <linux/of_irq.h>
  34 #include <linux/of_gpio.h>
  35 #include <linux/of_platform.h>
  36
  37 #define EMPTY_ADVALUE                                   950
  38 #define DRIFT_ADVALUE                                   70
  39 #define INVALID_ADVALUE                                 -1
  40 #define EV_ENCALL                       KEY_F4
  41 #define EV_MENU                         KEY_F1
  42
  43
  44 #if 0
  45 #define key_dbg(bdata, format, arg...)          \
  46         dev_printk(KERN_INFO , &bdata->input->dev , format , ## arg)
  47 #else
  48 #define key_dbg(bdata, format, arg...)
  49 #endif
  50
  51 #define DEFAULT_DEBOUNCE_INTERVAL       10  //10ms
  52 #define ADC_SAMPLE_TIME                  100
  53
  54 enum  rk_key_type{
  55        TYPE_GPIO = 1,
  56            TYPE_ADC
  57 };
  58
  59 struct rk_keys_button {
  60         u32 type;  //TYPE_GPIO, TYPE_ADC
  61     u32 code;  // key code
  62     char *desc;//key label
  63         u32 state; //key up & down state
  64     int gpio;  //gpio only
  65     int adc_value; //adc only
  66     int adc_state; //adc only
  67     int active_low;//gpio only
  68     int wakeup;    //gpio only
  69         struct timer_list timer;
  70 };
  71
  72 struct rk_keys_drvdata {
  73         int nbuttons;
  74         bool in_suspend;        /* Flag to indicate if we're suspending/resuming */
  75         int result;
  76     int rep;
  77         struct input_dev *input;
  78         struct delayed_work adc_poll_work;
  79     struct iio_channel *chan;
  80         struct rk_keys_button button[0];
  81 };
  82
  83 static struct input_dev *sinput_dev = NULL;
  84 static struct rk_keys_drvdata *spdata = NULL;
  85 static void * rk_key_get_drvdata(void)
  86 {
  87      BUG_ON(!spdata);
  88          return spdata;
  89 }
  90
  91 void rk_send_power_key(int state)
  92 {
  93         if (!sinput_dev)
  94                 return;
  95         if(state)
  96         {
  97                 input_report_key(sinput_dev, KEY_POWER, 1);
  98                 input_sync(sinput_dev);
  99         }
 100         else
 101         {
 102                 input_report_key(sinput_dev, KEY_POWER, 0);
 103                 input_sync(sinput_dev);
 104         }
 105 }
 106 EXPORT_SYMBOL(rk_send_power_key);
 107
 108 void rk_send_wakeup_key(void)
 109 {
 110         if (!sinput_dev)
 111                 return;
 112
 113         input_report_key(sinput_dev, KEY_WAKEUP, 1);
 114         input_sync(sinput_dev);
 115         input_report_key(sinput_dev, KEY_WAKEUP, 0);
 116         input_sync(sinput_dev);
 117 }
 118 EXPORT_SYMBOL(rk_send_wakeup_key);
 119
 120 static void keys_timer(unsigned long _data)
 121 {
 122     struct rk_keys_drvdata *pdata = rk_key_get_drvdata();
 123         struct rk_keys_button *button = (struct rk_keys_button *)_data;
 124         struct input_dev *input = pdata->input;
 125         int state;
 126
 127         if(button->type == TYPE_GPIO)
 128                 state = !!((gpio_get_value(button->gpio) ? 1 : 0) ^ button->active_low);
 129         else
 130                 state = !!button->adc_state;
 131
 132         if(button->state != state) {
 133                 button->state = state;
 134                 input_event(input, EV_KEY, button->code, button->state);
 135                 key_dbg(pdata, "%skey[%s]: report event[%d] state[%d]\n",
 136                         (button->type == TYPE_ADC)?"adc":"gpio", button->desc, button->code, button->state);
 137                 input_event(input, EV_KEY, button->code, button->state);
 138                 input_sync(input);
 139         }
 140
 141         if(state)
 142                 mod_timer(&button->timer,
 143                         jiffies + msecs_to_jiffies(DEFAULT_DEBOUNCE_INTERVAL));
 144
 145 }
 146
 147 static irqreturn_t keys_isr(int irq, void *dev_id)
 148 {
 149     struct rk_keys_drvdata *pdata = rk_key_get_drvdata();
 150         struct rk_keys_button *button = (struct rk_keys_button *)dev_id;
 151         struct input_dev *input = pdata->input;
 152         BUG_ON(irq != gpio_to_irq(button->gpio));
 153
 154     if(button->wakeup == 1 && pdata->in_suspend == true){
 155                 button->state = 1;
 156                 key_dbg(pdata, "wakeup: %skey[%s]: report event[%d] state[%d]\n",
 157                         (button->type == TYPE_ADC)?"adc":"gpio", button->desc, button->code, button->state);
 158                 input_event(input, EV_KEY, button->code, button->state);
 159                 input_sync(input);
 160     }
 161         mod_timer(&button->timer,
 162                                 jiffies + msecs_to_jiffies(DEFAULT_DEBOUNCE_INTERVAL));
 163         return IRQ_HANDLED;
 164 }
 165
 166 static ssize_t adc_value_show(struct device *dev, struct device_attribute *attr, char *buf)
 167 {
 168         struct rk_keys_drvdata *ddata = dev_get_drvdata(dev);
 169         return sprintf(buf, "adc_value: %d\n", ddata->result);
 170 }
 171 static DEVICE_ATTR(get_adc_value, S_IRUGO | S_IWUSR, adc_value_show, NULL);
 172
 173 static const struct of_device_id rk_key_match[] = {
 174         { .compatible = "rockchip,key", .data = NULL},
 175         {},
 176 };
 177 MODULE_DEVICE_TABLE(of, rk_key_match);
 178
 179 static int rk_key_adc_iio_read(struct rk_keys_drvdata *data)
 180 {
 181         struct iio_channel *channel = data->chan;
 182         int val, ret;
 183
 184         ret = iio_read_channel_raw(channel, &val);
 185         if (ret < 0) {
 186                 pr_err("read channel() error: %d\n", ret);
 187                 return ret;
 188         }
 189         return val;
 190 }
 191
 192 static void adc_key_poll(struct work_struct *work)
 193 {
 194         struct rk_keys_drvdata *ddata;
 195         int i, result = -1;
 196
 197         ddata = container_of(work, struct rk_keys_drvdata, adc_poll_work.work);
 198         if (!ddata->in_suspend)
 199                 result = rk_key_adc_iio_read(ddata);
 200
 201         if(result > INVALID_ADVALUE && result < EMPTY_ADVALUE)
 202                 ddata->result = result;
 203         for (i = 0; i < ddata->nbuttons; i++) {
 204                 struct rk_keys_button *button = &ddata->button[i];
 205                 if(!button->adc_value)
 206                         continue;
 207
 208                 if(result < button->adc_value + DRIFT_ADVALUE &&
 209                         result > button->adc_value - DRIFT_ADVALUE)
 210                         button->adc_state = 1;
 211                 else
 212                         button->adc_state = 0;
 213                 if(button->state != button->adc_state)
 214                         mod_timer(&button->timer,
 215                                 jiffies + msecs_to_jiffies(DEFAULT_DEBOUNCE_INTERVAL));
 216         }
 217     schedule_delayed_work(&ddata->adc_poll_work,
 218             msecs_to_jiffies(ADC_SAMPLE_TIME));
 219 }
 220
 221 static int rk_key_type_get(struct device_node *node, struct rk_keys_button *button)
 222 {
 223         u32 adc_value;
 224
 225         if (!of_property_read_u32(node, "rockchip,adc_value", &adc_value))
 226         return TYPE_ADC;
 227     else if(of_get_gpio(node, 0) >= 0)
 228             return TYPE_GPIO;
 229         else
 230                 return -1;
 231 }
 232
 233 static int rk_keys_parse_dt(struct rk_keys_drvdata *pdata,
 234                              struct platform_device *pdev)
 235 {
 236     struct device_node *node = pdev->dev.of_node;
 237     struct device_node *child_node;
 238     struct iio_channel *chan;
 239     int ret, gpio, i =0;
 240         u32 code, adc_value, flags;;
 241
 242         chan = iio_channel_get(&pdev->dev, NULL);
 243     if (IS_ERR(chan))
 244         goto error_ret;
 245     pdata->chan = chan;
 246
 247         for_each_child_of_node(node, child_node) {
 248                 if(of_property_read_u32(child_node, "linux,code", &code)) {
 249                         dev_err(&pdev->dev, "Missing linux,code property in the DT.\n");
 250                         ret = -EINVAL;
 251                         goto error_ret;
 252                 }
 253         pdata->button[i].code = code;
 254                 pdata->button[i].desc = of_get_property(child_node, "label", NULL);
 255                 pdata->button[i].type = rk_key_type_get(child_node, &pdata->button[i]);
 256                 switch(pdata->button[i].type)
 257                 {
 258                     case TYPE_GPIO:
 259                                 gpio = of_get_gpio_flags(child_node, 0, &flags);
 260                                 if (gpio < 0) {
 261                                         ret = gpio;
 262                                         if (ret != -EPROBE_DEFER)
 263                                                 dev_err(&pdev->dev,"Failed to get gpio flags, error: %d\n",
 264                                                         ret);
 265                                         goto error_ret;
 266                                 }
 267
 268                                 pdata->button[i].gpio = gpio;
 269                         pdata->button[i].active_low = flags & OF_GPIO_ACTIVE_LOW;
 270                                 pdata->button[i].wakeup = !!of_get_property(child_node, "gpio-key,wakeup", NULL);
 271                                 break;
 272
 273                         case TYPE_ADC:
 274                             if (of_property_read_u32(child_node, "rockchip,adc_value", &adc_value)) {
 275                                     dev_err(&pdev->dev, "Missing rockchip,adc_value property in the DT.\n");
 276                                     ret = -EINVAL;
 277                                     goto error_ret;
 278                             }
 279                                 pdata->button[i].adc_value = adc_value;
 280                                 break;
 281
 282                         default:
 283                                 dev_err(&pdev->dev, "Error rockchip,type property in the DT.\n");
 284                             ret = -EINVAL;
 285                             goto error_ret;
 286                 }
 287             i++;
 288         }
 289
 290         return 0;
 291
 292 error_ret:
 293                 return ret;
 294
 295 }
 296
 297 static int  keys_probe(struct platform_device *pdev)
 298 {
 299         struct device *dev = &pdev->dev;
 300         struct device_node *np = pdev->dev.of_node;
 301         struct rk_keys_drvdata *ddata = NULL;
 302         struct input_dev *input = NULL;
 303         int i, error = 0;
 304         int wakeup, key_num = 0;
 305
 306         key_num = of_get_child_count(np);
 307         if (key_num == 0) {
 308                 error = -ENODEV;
 309                 return error;
 310         }
 311
 312     ddata = devm_kzalloc(dev, sizeof(struct rk_keys_drvdata) +
 313             key_num * sizeof(struct rk_keys_button),
 314                 GFP_KERNEL);
 315
 316         input = devm_input_allocate_device(dev);
 317         if (!ddata || !input) {
 318                 error = -ENOMEM;
 319                 return error;
 320         }
 321         platform_set_drvdata(pdev, ddata);
 322
 323         input->name = "rk29-keypad";//pdev->name;
 324         input->phys = "gpio-keys/input0";
 325         input->dev.parent = dev;
 326
 327         input->id.bustype = BUS_HOST;
 328         input->id.vendor = 0x0001;
 329         input->id.product = 0x0001;
 330         input->id.version = 0x0100;
 331         ddata->input = input;
 332
 333         //parse info from dt
 334         ddata->nbuttons = key_num;
 335         error = rk_keys_parse_dt(ddata, pdev);
 336         if(error)
 337             goto fail0;
 338
 339         /* Enable auto repeat feature of Linux input subsystem */
 340         if (ddata->rep)
 341                 __set_bit(EV_REP, input->evbit);
 342
 343         for (i = 0; i < ddata->nbuttons; i++) {
 344                 struct rk_keys_button *button = &ddata->button[i];
 345
 346                 if (button->code){
 347                         setup_timer(&button->timer,
 348                                 keys_timer, (unsigned long)button);}
 349
 350                 if (button->wakeup)
 351                         wakeup = 1;
 352
 353                 input_set_capability(input, EV_KEY, button->code);
 354         }
 355
 356         for (i = 0; i < ddata->nbuttons; i++) {
 357                 struct rk_keys_button *button = &ddata->button[i];
 358
 359                 if(button->type == TYPE_GPIO) {
 360                         error = devm_gpio_request(dev, button->gpio, button->desc ?: "keys");
 361                         if (error < 0) {
 362                                 pr_err("gpio-keys: failed to request GPIO %d,"
 363                                         " error %d\n", button->gpio, error);
 364                                 goto fail1;
 365                         }
 366
 367                         error = gpio_direction_input(button->gpio);
 368                         if (error < 0) {
 369                                 pr_err("gpio-keys: failed to configure input"
 370                                         " direction for GPIO %d, error %d\n",
 371                                         button->gpio, error);
 372                                 gpio_free(button->gpio);
 373                                 goto fail1;
 374                         }
 375
 376                         int irq = gpio_to_irq(button->gpio);
 377                         if (irq < 0) {
 378                                 error = irq;
 379                                 pr_err("gpio-keys: Unable to get irq number"
 380                                         " for GPIO %d, error %d\n",
 381                                         button->gpio, error);
 382                                 gpio_free(button->gpio);
 383                                 goto fail1;
 384                         }
 385
 386                         error = devm_request_irq(dev, irq, keys_isr,
 387                                             (button->active_low)?IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING,
 388                                             button->desc ? button->desc : "keys",
 389                                             button);
 390                         if (error) {
 391                                 pr_err("gpio-keys: Unable to claim irq %d; error %d\n",
 392                                         irq, error);
 393                                 gpio_free(button->gpio);
 394                                 goto fail1;
 395                         }
 396                 }
 397         }
 398
 399         input_set_capability(input, EV_KEY, KEY_WAKEUP);
 400         device_init_wakeup(dev, wakeup);
 401
 402         error = input_register_device(input);
 403         if (error) {
 404                 pr_err("gpio-keys: Unable to register input device, "
 405                         "error: %d\n", error);
 406                 goto fail2;
 407         }
 408
 409         //adc polling work
 410         INIT_DELAYED_WORK(&ddata->adc_poll_work, adc_key_poll);
 411         schedule_delayed_work(&ddata->adc_poll_work,
 412                                         msecs_to_jiffies(ADC_SAMPLE_TIME));
 413
 414     spdata = ddata;
 415         sinput_dev = input;
 416         return error;
 417
 418  fail2:
 419         device_init_wakeup(dev, 0);
 420  fail1:
 421         while (--i >= 0) {
 422                 del_timer_sync(&ddata->button[i].timer);
 423         }
 424  fail0:
 425         platform_set_drvdata(pdev, NULL);
 426
 427         return error;
 428 }
 429
 430 static int keys_remove(struct platform_device *pdev)
 431 {
 432         struct device *dev = &pdev->dev;
 433         struct rk_keys_drvdata *ddata = dev_get_drvdata(dev);
 434         struct input_dev *input = ddata->input;
 435         int i;
 436
 437         device_init_wakeup(dev, 0);
 438         for (i = 0; i < ddata->nbuttons; i++) {
 439                 del_timer_sync(&ddata->button[i].timer);
 440         }
 441         cancel_delayed_work_sync(&ddata->adc_poll_work);
 442         input_unregister_device(input);
 443
 444         sinput_dev = NULL;
 445         spdata = NULL;
 446
 447         return 0;
 448 }
 449
 450
 451 #ifdef CONFIG_PM
 452 static int keys_suspend(struct device *dev)
 453 {
 454         struct rk_keys_drvdata *ddata = dev_get_drvdata(dev);
 455         int i;
 456
 457         ddata->in_suspend = true;
 458         if (device_may_wakeup(dev)) {
 459                 for (i = 0; i < ddata->nbuttons; i++) {
 460                         struct rk_keys_button *button = ddata->button + i;
 461                         if (button->wakeup) {
 462                                 int irq = gpio_to_irq(button->gpio);
 463                                 enable_irq_wake(irq);
 464                         }
 465                 }
 466         }
 467
 468         return 0;
 469 }
 470
 471 static int keys_resume(struct device *dev)
 472 {
 473         struct rk_keys_drvdata *ddata = dev_get_drvdata(dev);
 474         int i;
 475
 476         if (device_may_wakeup(dev)) {
 477                 for (i = 0; i < ddata->nbuttons; i++) {
 478                         struct rk_keys_button *button = ddata->button + i;
 479                         if (button->wakeup) {
 480                                 int irq = gpio_to_irq(button->gpio);
 481                                 disable_irq_wake(irq);
 482                         }
 483                 }
 484                 preempt_disable();
 485                 if (local_softirq_pending())
 486                         do_softirq(); // for call resend_irqs, which may call keys_isr
 487                 preempt_enable_no_resched();
 488         }
 489
 490         ddata->in_suspend = false;
 491
 492         return 0;
 493 }
 494
 495 static const struct dev_pm_ops keys_pm_ops = {
 496         .suspend        = keys_suspend,
 497         .resume         = keys_resume,
 498 };
 499 #endif
 500
 501 static struct platform_driver keys_device_driver = {
 502         .probe          = keys_probe,
 503         .remove         = keys_remove,
 504         .driver         = {
 505                 .name   = "rk-keypad",
 506                 .owner  = THIS_MODULE,
 507                 .of_match_table = rk_key_match,
 508 #ifdef CONFIG_PM
 509                 .pm     = &keys_pm_ops,
 510 #endif
 511         }
 512 };
 513
 514 module_platform_driver(keys_device_driver);
 515