drivers/input/keyboard/nomadik-ske-keypad.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) ST-Ericsson SA 2010
   4  *
   5  * Author: Naveen Kumar G <naveen.gaddipati@stericsson.com> for ST-Ericsson
   6  * Author: Sundar Iyer <sundar.iyer@stericsson.com> for ST-Ericsson
   7  *
   8  * Keypad controller driver for the SKE (Scroll Key Encoder) module used in
   9  * the Nomadik 8815 and Ux500 platforms.
  10  */
  11
  12 #include <linux/platform_device.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/spinlock.h>
  15 #include <linux/io.h>
  16 #include <linux/delay.h>
  17 #include <linux/input.h>
  18 #include <linux/slab.h>
  19 #include <linux/clk.h>
  20 #include <linux/module.h>
  21
  22 #include <linux/platform_data/keypad-nomadik-ske.h>
  23
  24 /* SKE_CR bits */
  25 #define SKE_KPMLT       (0x1 << 6)
  26 #define SKE_KPCN        (0x7 << 3)
  27 #define SKE_KPASEN      (0x1 << 2)
  28 #define SKE_KPASON      (0x1 << 7)
  29
  30 /* SKE_IMSC bits */
  31 #define SKE_KPIMA       (0x1 << 2)
  32
  33 /* SKE_ICR bits */
  34 #define SKE_KPICS       (0x1 << 3)
  35 #define SKE_KPICA       (0x1 << 2)
  36
  37 /* SKE_RIS bits */
  38 #define SKE_KPRISA      (0x1 << 2)
  39
  40 #define SKE_KEYPAD_ROW_SHIFT    3
  41 #define SKE_KPD_NUM_ROWS        8
  42 #define SKE_KPD_NUM_COLS        8
  43
  44 /* keypad auto scan registers */
  45 #define SKE_ASR0        0x20
  46 #define SKE_ASR1        0x24
  47 #define SKE_ASR2        0x28
  48 #define SKE_ASR3        0x2C
  49
  50 #define SKE_NUM_ASRX_REGISTERS  (4)
  51 #define KEY_PRESSED_DELAY       10
  52
  53 /**
  54  * struct ske_keypad  - data structure used by keypad driver
  55  * @irq:        irq no
  56  * @reg_base:   ske registers base address
  57  * @input:      pointer to input device object
  58  * @board:      keypad platform device
  59  * @keymap:     matrix scan code table for keycodes
  60  * @clk:        clock structure pointer
  61  * @pclk:       clock structure pointer
  62  * @ske_keypad_lock: spinlock protecting the keypad read/writes
  63  */
  64 struct ske_keypad {
  65         int irq;
  66         void __iomem *reg_base;
  67         struct input_dev *input;
  68         const struct ske_keypad_platform_data *board;
  69         unsigned short keymap[SKE_KPD_NUM_ROWS * SKE_KPD_NUM_COLS];
  70         struct clk *clk;
  71         struct clk *pclk;
  72         spinlock_t ske_keypad_lock;
  73 };
  74
  75 static void ske_keypad_set_bits(struct ske_keypad *keypad, u16 addr,
  76                 u8 mask, u8 data)
  77 {
  78         u32 ret;
  79
  80         spin_lock(&keypad->ske_keypad_lock);
  81
  82         ret = readl(keypad->reg_base + addr);
  83         ret &= ~mask;
  84         ret |= data;
  85         writel(ret, keypad->reg_base + addr);
  86
  87         spin_unlock(&keypad->ske_keypad_lock);
  88 }
  89
  90 /*
  91  * ske_keypad_chip_init: init keypad controller configuration
  92  *
  93  * Enable Multi key press detection, auto scan mode
  94  */
  95 static int __init ske_keypad_chip_init(struct ske_keypad *keypad)
  96 {
  97         u32 value;
  98         int timeout = keypad->board->debounce_ms;
  99
 100         /* check SKE_RIS to be 0 */
 101         while ((readl(keypad->reg_base + SKE_RIS) != 0x00000000) && timeout--)
 102                 cpu_relax();
 103
 104         if (timeout == -1)
 105                 return -EINVAL;
 106
 107         /*
 108          * set debounce value
 109          * keypad dbounce is configured in DBCR[15:8]
 110          * dbounce value in steps of 32/32.768 ms
 111          */
 112         spin_lock(&keypad->ske_keypad_lock);
 113         value = readl(keypad->reg_base + SKE_DBCR);
 114         value = value & 0xff;
 115         value |= ((keypad->board->debounce_ms * 32000)/32768) << 8;
 116         writel(value, keypad->reg_base + SKE_DBCR);
 117         spin_unlock(&keypad->ske_keypad_lock);
 118
 119         /* enable multi key detection */
 120         ske_keypad_set_bits(keypad, SKE_CR, 0x0, SKE_KPMLT);
 121
 122         /*
 123          * set up the number of columns
 124          * KPCN[5:3] defines no. of keypad columns to be auto scanned
 125          */
 126         value = (keypad->board->kcol - 1) << 3;
 127         ske_keypad_set_bits(keypad, SKE_CR, SKE_KPCN, value);
 128
 129         /* clear keypad interrupt for auto(and pending SW) scans */
 130         ske_keypad_set_bits(keypad, SKE_ICR, 0x0, SKE_KPICA | SKE_KPICS);
 131
 132         /* un-mask keypad interrupts */
 133         ske_keypad_set_bits(keypad, SKE_IMSC, 0x0, SKE_KPIMA);
 134
 135         /* enable automatic scan */
 136         ske_keypad_set_bits(keypad, SKE_CR, 0x0, SKE_KPASEN);
 137
 138         return 0;
 139 }
 140
 141 static void ske_keypad_report(struct ske_keypad *keypad, u8 status, int col)
 142 {
 143         int row = 0, code, pos;
 144         struct input_dev *input = keypad->input;
 145         u32 ske_ris;
 146         int key_pressed;
 147         int num_of_rows;
 148
 149         /* find out the row */
 150         num_of_rows = hweight8(status);
 151         do {
 152                 pos = __ffs(status);
 153                 row = pos;
 154                 status &= ~(1 << pos);
 155
 156                 code = MATRIX_SCAN_CODE(row, col, SKE_KEYPAD_ROW_SHIFT);
 157                 ske_ris = readl(keypad->reg_base + SKE_RIS);
 158                 key_pressed = ske_ris & SKE_KPRISA;
 159
 160                 input_event(input, EV_MSC, MSC_SCAN, code);
 161                 input_report_key(input, keypad->keymap[code], key_pressed);
 162                 input_sync(input);
 163                 num_of_rows--;
 164         } while (num_of_rows);
 165 }
 166
 167 static void ske_keypad_read_data(struct ske_keypad *keypad)
 168 {
 169         u8 status;
 170         int col = 0;
 171         int ske_asr, i;
 172
 173         /*
 174          * Read the auto scan registers
 175          *
 176          * Each SKE_ASRx (x=0 to x=3) contains two row values.
 177          * lower byte contains row value for column 2*x,
 178          * upper byte contains row value for column 2*x + 1
 179          */
 180         for (i = 0; i < SKE_NUM_ASRX_REGISTERS; i++) {
 181                 ske_asr = readl(keypad->reg_base + SKE_ASR0 + (4 * i));
 182                 if (!ske_asr)
 183                         continue;
 184
 185                 /* now that ASRx is zero, find out the coloumn x and row y */
 186                 status = ske_asr & 0xff;
 187                 if (status) {
 188                         col = i * 2;
 189                         ske_keypad_report(keypad, status, col);
 190                 }
 191                 status = (ske_asr & 0xff00) >> 8;
 192                 if (status) {
 193                         col = (i * 2) + 1;
 194                         ske_keypad_report(keypad, status, col);
 195                 }
 196         }
 197 }
 198
 199 static irqreturn_t ske_keypad_irq(int irq, void *dev_id)
 200 {
 201         struct ske_keypad *keypad = dev_id;
 202         int timeout = keypad->board->debounce_ms;
 203
 204         /* disable auto scan interrupt; mask the interrupt generated */
 205         ske_keypad_set_bits(keypad, SKE_IMSC, ~SKE_KPIMA, 0x0);
 206         ske_keypad_set_bits(keypad, SKE_ICR, 0x0, SKE_KPICA);
 207
 208         while ((readl(keypad->reg_base + SKE_CR) & SKE_KPASON) && --timeout)
 209                 cpu_relax();
 210
 211         /* SKEx registers are stable and can be read */
 212         ske_keypad_read_data(keypad);
 213
 214         /* wait until raw interrupt is clear */
 215         while ((readl(keypad->reg_base + SKE_RIS)) && --timeout)
 216                 msleep(KEY_PRESSED_DELAY);
 217
 218         /* enable auto scan interrupts */
 219         ske_keypad_set_bits(keypad, SKE_IMSC, 0x0, SKE_KPIMA);
 220
 221         return IRQ_HANDLED;
 222 }
 223
 224 static int __init ske_keypad_probe(struct platform_device *pdev)
 225 {
 226         const struct ske_keypad_platform_data *plat =
 227                         dev_get_platdata(&pdev->dev);
 228         struct ske_keypad *keypad;
 229         struct input_dev *input;
 230         struct resource *res;
 231         int irq;
 232         int error;
 233
 234         if (!plat) {
 235                 dev_err(&pdev->dev, "invalid keypad platform data\n");
 236                 return -EINVAL;
 237         }
 238
 239         irq = platform_get_irq(pdev, 0);
 240         if (irq < 0)
 241                 return -EINVAL;
 242
 243         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 244         if (!res) {
 245                 dev_err(&pdev->dev, "missing platform resources\n");
 246                 return -EINVAL;
 247         }
 248
 249         keypad = kzalloc(sizeof(struct ske_keypad), GFP_KERNEL);
 250         input = input_allocate_device();
 251         if (!keypad || !input) {
 252                 dev_err(&pdev->dev, "failed to allocate keypad memory\n");
 253                 error = -ENOMEM;
 254                 goto err_free_mem;
 255         }
 256
 257         keypad->irq = irq;
 258         keypad->board = plat;
 259         keypad->input = input;
 260         spin_lock_init(&keypad->ske_keypad_lock);
 261
 262         if (!request_mem_region(res->start, resource_size(res), pdev->name)) {
 263                 dev_err(&pdev->dev, "failed to request I/O memory\n");
 264                 error = -EBUSY;
 265                 goto err_free_mem;
 266         }
 267
 268         keypad->reg_base = ioremap(res->start, resource_size(res));
 269         if (!keypad->reg_base) {
 270                 dev_err(&pdev->dev, "failed to remap I/O memory\n");
 271                 error = -ENXIO;
 272                 goto err_free_mem_region;
 273         }
 274
 275         keypad->pclk = clk_get(&pdev->dev, "apb_pclk");
 276         if (IS_ERR(keypad->pclk)) {
 277                 dev_err(&pdev->dev, "failed to get pclk\n");
 278                 error = PTR_ERR(keypad->pclk);
 279                 goto err_iounmap;
 280         }
 281
 282         keypad->clk = clk_get(&pdev->dev, NULL);
 283         if (IS_ERR(keypad->clk)) {
 284                 dev_err(&pdev->dev, "failed to get clk\n");
 285                 error = PTR_ERR(keypad->clk);
 286                 goto err_pclk;
 287         }
 288
 289         input->id.bustype = BUS_HOST;
 290         input->name = "ux500-ske-keypad";
 291         input->dev.parent = &pdev->dev;
 292
 293         error = matrix_keypad_build_keymap(plat->keymap_data, NULL,
 294                                            SKE_KPD_NUM_ROWS, SKE_KPD_NUM_COLS,
 295                                            keypad->keymap, input);
 296         if (error) {
 297                 dev_err(&pdev->dev, "Failed to build keymap\n");
 298                 goto err_clk;
 299         }
 300
 301         input_set_capability(input, EV_MSC, MSC_SCAN);
 302         if (!plat->no_autorepeat)
 303                 __set_bit(EV_REP, input->evbit);
 304
 305         error = clk_prepare_enable(keypad->pclk);
 306         if (error) {
 307                 dev_err(&pdev->dev, "Failed to prepare/enable pclk\n");
 308                 goto err_clk;
 309         }
 310
 311         error = clk_prepare_enable(keypad->clk);
 312         if (error) {
 313                 dev_err(&pdev->dev, "Failed to prepare/enable clk\n");
 314                 goto err_pclk_disable;
 315         }
 316
 317
 318         /* go through board initialization helpers */
 319         if (keypad->board->init)
 320                 keypad->board->init();
 321
 322         error = ske_keypad_chip_init(keypad);
 323         if (error) {
 324                 dev_err(&pdev->dev, "unable to init keypad hardware\n");
 325                 goto err_clk_disable;
 326         }
 327
 328         error = request_threaded_irq(keypad->irq, NULL, ske_keypad_irq,
 329                                      IRQF_ONESHOT, "ske-keypad", keypad);
 330         if (error) {
 331                 dev_err(&pdev->dev, "allocate irq %d failed\n", keypad->irq);
 332                 goto err_clk_disable;
 333         }
 334
 335         error = input_register_device(input);
 336         if (error) {
 337                 dev_err(&pdev->dev,
 338                                 "unable to register input device: %d\n", error);
 339                 goto err_free_irq;
 340         }
 341
 342         if (plat->wakeup_enable)
 343                 device_init_wakeup(&pdev->dev, true);
 344
 345         platform_set_drvdata(pdev, keypad);
 346
 347         return 0;
 348
 349 err_free_irq:
 350         free_irq(keypad->irq, keypad);
 351 err_clk_disable:
 352         clk_disable_unprepare(keypad->clk);
 353 err_pclk_disable:
 354         clk_disable_unprepare(keypad->pclk);
 355 err_clk:
 356         clk_put(keypad->clk);
 357 err_pclk:
 358         clk_put(keypad->pclk);
 359 err_iounmap:
 360         iounmap(keypad->reg_base);
 361 err_free_mem_region:
 362         release_mem_region(res->start, resource_size(res));
 363 err_free_mem:
 364         input_free_device(input);
 365         kfree(keypad);
 366         return error;
 367 }
 368
 369 static int ske_keypad_remove(struct platform_device *pdev)
 370 {
 371         struct ske_keypad *keypad = platform_get_drvdata(pdev);
 372         struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 373
 374         free_irq(keypad->irq, keypad);
 375
 376         input_unregister_device(keypad->input);
 377
 378         clk_disable_unprepare(keypad->clk);
 379         clk_put(keypad->clk);
 380
 381         if (keypad->board->exit)
 382                 keypad->board->exit();
 383
 384         iounmap(keypad->reg_base);
 385         release_mem_region(res->start, resource_size(res));
 386         kfree(keypad);
 387
 388         return 0;
 389 }
 390
 391 #ifdef CONFIG_PM_SLEEP
 392 static int ske_keypad_suspend(struct device *dev)
 393 {
 394         struct platform_device *pdev = to_platform_device(dev);
 395         struct ske_keypad *keypad = platform_get_drvdata(pdev);
 396         int irq = platform_get_irq(pdev, 0);
 397
 398         if (device_may_wakeup(dev))
 399                 enable_irq_wake(irq);
 400         else
 401                 ske_keypad_set_bits(keypad, SKE_IMSC, ~SKE_KPIMA, 0x0);
 402
 403         return 0;
 404 }
 405
 406 static int ske_keypad_resume(struct device *dev)
 407 {
 408         struct platform_device *pdev = to_platform_device(dev);
 409         struct ske_keypad *keypad = platform_get_drvdata(pdev);
 410         int irq = platform_get_irq(pdev, 0);
 411
 412         if (device_may_wakeup(dev))
 413                 disable_irq_wake(irq);
 414         else
 415                 ske_keypad_set_bits(keypad, SKE_IMSC, 0x0, SKE_KPIMA);
 416
 417         return 0;
 418 }
 419 #endif
 420
 421 static SIMPLE_DEV_PM_OPS(ske_keypad_dev_pm_ops,
 422                          ske_keypad_suspend, ske_keypad_resume);
 423
 424 static struct platform_driver ske_keypad_driver = {
 425         .driver = {
 426                 .name = "nmk-ske-keypad",
 427                 .pm = &ske_keypad_dev_pm_ops,
 428         },
 429         .remove = ske_keypad_remove,
 430 };
 431
 432 module_platform_driver_probe(ske_keypad_driver, ske_keypad_probe);
 433
 434 MODULE_LICENSE("GPL v2");
 435 MODULE_AUTHOR("Naveen Kumar <naveen.gaddipati@stericsson.com> / Sundar Iyer <sundar.iyer@stericsson.com>");
 436 MODULE_DESCRIPTION("Nomadik Scroll-Key-Encoder Keypad Driver");
 437 MODULE_ALIAS("platform:nomadik-ske-keypad");