linux/drivers/input/keyboard/nomadik-ske-keypad.c
<<
>>
Prefs
   1/*
   2 * Copyright (C) ST-Ericsson SA 2010
   3 *
   4 * Author: Naveen Kumar G <naveen.gaddipati@stericsson.com> for ST-Ericsson
   5 * Author: Sundar Iyer <sundar.iyer@stericsson.com> for ST-Ericsson
   6 *
   7 * License terms:GNU General Public License (GPL) version 2
   8 *
   9 * Keypad controller driver for the SKE (Scroll Key Encoder) module used in
  10 * the Nomadik 8815 and Ux500 platforms.
  11 */
  12
  13#include <linux/platform_device.h>
  14#include <linux/interrupt.h>
  15#include <linux/spinlock.h>
  16#include <linux/io.h>
  17#include <linux/delay.h>
  18#include <linux/input.h>
  19#include <linux/slab.h>
  20#include <linux/clk.h>
  21#include <linux/module.h>
  22
  23#include <linux/platform_data/keypad-nomadik-ske.h>
  24
  25/* SKE_CR bits */
  26#define SKE_KPMLT       (0x1 << 6)
  27#define SKE_KPCN        (0x7 << 3)
  28#define SKE_KPASEN      (0x1 << 2)
  29#define SKE_KPASON      (0x1 << 7)
  30
  31/* SKE_IMSC bits */
  32#define SKE_KPIMA       (0x1 << 2)
  33
  34/* SKE_ICR bits */
  35#define SKE_KPICS       (0x1 << 3)
  36#define SKE_KPICA       (0x1 << 2)
  37
  38/* SKE_RIS bits */
  39#define SKE_KPRISA      (0x1 << 2)
  40
  41#define SKE_KEYPAD_ROW_SHIFT    3
  42#define SKE_KPD_NUM_ROWS        8
  43#define SKE_KPD_NUM_COLS        8
  44
  45/* keypad auto scan registers */
  46#define SKE_ASR0        0x20
  47#define SKE_ASR1        0x24
  48#define SKE_ASR2        0x28
  49#define SKE_ASR3        0x2C
  50
  51#define SKE_NUM_ASRX_REGISTERS  (4)
  52#define KEY_PRESSED_DELAY       10
  53
  54/**
  55 * struct ske_keypad  - data structure used by keypad driver
  56 * @irq:        irq no
  57 * @reg_base:   ske regsiters base address
  58 * @input:      pointer to input device object
  59 * @board:      keypad platform device
  60 * @keymap:     matrix scan code table for keycodes
  61 * @clk:        clock structure pointer
  62 */
  63struct ske_keypad {
  64        int irq;
  65        void __iomem *reg_base;
  66        struct input_dev *input;
  67        const struct ske_keypad_platform_data *board;
  68        unsigned short keymap[SKE_KPD_NUM_ROWS * SKE_KPD_NUM_COLS];
  69        struct clk *clk;
  70        struct clk *pclk;
  71        spinlock_t ske_keypad_lock;
  72};
  73
  74static void ske_keypad_set_bits(struct ske_keypad *keypad, u16 addr,
  75                u8 mask, u8 data)
  76{
  77        u32 ret;
  78
  79        spin_lock(&keypad->ske_keypad_lock);
  80
  81        ret = readl(keypad->reg_base + addr);
  82        ret &= ~mask;
  83        ret |= data;
  84        writel(ret, keypad->reg_base + addr);
  85
  86        spin_unlock(&keypad->ske_keypad_lock);
  87}
  88
  89/*
  90 * ske_keypad_chip_init: init keypad controller configuration
  91 *
  92 * Enable Multi key press detection, auto scan mode
  93 */
  94static int __init ske_keypad_chip_init(struct ske_keypad *keypad)
  95{
  96        u32 value;
  97        int timeout = keypad->board->debounce_ms;
  98
  99        /* check SKE_RIS to be 0 */
 100        while ((readl(keypad->reg_base + SKE_RIS) != 0x00000000) && timeout--)
 101                cpu_relax();
 102
 103        if (!timeout)
 104                return -EINVAL;
 105
 106        /*
 107         * set debounce value
 108         * keypad dbounce is configured in DBCR[15:8]
 109         * dbounce value in steps of 32/32.768 ms
 110         */
 111        spin_lock(&keypad->ske_keypad_lock);
 112        value = readl(keypad->reg_base + SKE_DBCR);
 113        value = value & 0xff;
 114        value |= ((keypad->board->debounce_ms * 32000)/32768) << 8;
 115        writel(value, keypad->reg_base + SKE_DBCR);
 116        spin_unlock(&keypad->ske_keypad_lock);
 117
 118        /* enable multi key detection */
 119        ske_keypad_set_bits(keypad, SKE_CR, 0x0, SKE_KPMLT);
 120
 121        /*
 122         * set up the number of columns
 123         * KPCN[5:3] defines no. of keypad columns to be auto scanned
 124         */
 125        value = (keypad->board->kcol - 1) << 3;
 126        ske_keypad_set_bits(keypad, SKE_CR, SKE_KPCN, value);
 127
 128        /* clear keypad interrupt for auto(and pending SW) scans */
 129        ske_keypad_set_bits(keypad, SKE_ICR, 0x0, SKE_KPICA | SKE_KPICS);
 130
 131        /* un-mask keypad interrupts */
 132        ske_keypad_set_bits(keypad, SKE_IMSC, 0x0, SKE_KPIMA);
 133
 134        /* enable automatic scan */
 135        ske_keypad_set_bits(keypad, SKE_CR, 0x0, SKE_KPASEN);
 136
 137        return 0;
 138}
 139
 140static void ske_keypad_report(struct ske_keypad *keypad, u8 status, int col)
 141{
 142        int row = 0, code, pos;
 143        struct input_dev *input = keypad->input;
 144        u32 ske_ris;
 145        int key_pressed;
 146        int num_of_rows;
 147
 148        /* find out the row */
 149        num_of_rows = hweight8(status);
 150        do {
 151                pos = __ffs(status);
 152                row = pos;
 153                status &= ~(1 << pos);
 154
 155                code = MATRIX_SCAN_CODE(row, col, SKE_KEYPAD_ROW_SHIFT);
 156                ske_ris = readl(keypad->reg_base + SKE_RIS);
 157                key_pressed = ske_ris & SKE_KPRISA;
 158
 159                input_event(input, EV_MSC, MSC_SCAN, code);
 160                input_report_key(input, keypad->keymap[code], key_pressed);
 161                input_sync(input);
 162                num_of_rows--;
 163        } while (num_of_rows);
 164}
 165
 166static void ske_keypad_read_data(struct ske_keypad *keypad)
 167{
 168        u8 status;
 169        int col = 0;
 170        int ske_asr, i;
 171
 172        /*
 173         * Read the auto scan registers
 174         *
 175         * Each SKE_ASRx (x=0 to x=3) contains two row values.
 176         * lower byte contains row value for column 2*x,
 177         * upper byte contains row value for column 2*x + 1
 178         */
 179        for (i = 0; i < SKE_NUM_ASRX_REGISTERS; i++) {
 180                ske_asr = readl(keypad->reg_base + SKE_ASR0 + (4 * i));
 181                if (!ske_asr)
 182                        continue;
 183
 184                /* now that ASRx is zero, find out the coloumn x and row y */
 185                status = ske_asr & 0xff;
 186                if (status) {
 187                        col = i * 2;
 188                        ske_keypad_report(keypad, status, col);
 189                }
 190                status = (ske_asr & 0xff00) >> 8;
 191                if (status) {
 192                        col = (i * 2) + 1;
 193                        ske_keypad_report(keypad, status, col);
 194                }
 195        }
 196}
 197
 198static irqreturn_t ske_keypad_irq(int irq, void *dev_id)
 199{
 200        struct ske_keypad *keypad = dev_id;
 201        int timeout = keypad->board->debounce_ms;
 202
 203        /* disable auto scan interrupt; mask the interrupt generated */
 204        ske_keypad_set_bits(keypad, SKE_IMSC, ~SKE_KPIMA, 0x0);
 205        ske_keypad_set_bits(keypad, SKE_ICR, 0x0, SKE_KPICA);
 206
 207        while ((readl(keypad->reg_base + SKE_CR) & SKE_KPASON) && --timeout)
 208                cpu_relax();
 209
 210        /* SKEx registers are stable and can be read */
 211        ske_keypad_read_data(keypad);
 212
 213        /* wait until raw interrupt is clear */
 214        while ((readl(keypad->reg_base + SKE_RIS)) && --timeout)
 215                msleep(KEY_PRESSED_DELAY);
 216
 217        /* enable auto scan interrupts */
 218        ske_keypad_set_bits(keypad, SKE_IMSC, 0x0, SKE_KPIMA);
 219
 220        return IRQ_HANDLED;
 221}
 222
 223static int __init ske_keypad_probe(struct platform_device *pdev)
 224{
 225        const struct ske_keypad_platform_data *plat = pdev->dev.platform_data;
 226        struct ske_keypad *keypad;
 227        struct input_dev *input;
 228        struct resource *res;
 229        int irq;
 230        int error;
 231
 232        if (!plat) {
 233                dev_err(&pdev->dev, "invalid keypad platform data\n");
 234                return -EINVAL;
 235        }
 236
 237        irq = platform_get_irq(pdev, 0);
 238        if (irq < 0) {
 239                dev_err(&pdev->dev, "failed to get keypad irq\n");
 240                return -EINVAL;
 241        }
 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
 349err_free_irq:
 350        free_irq(keypad->irq, keypad);
 351err_clk_disable:
 352        clk_disable_unprepare(keypad->clk);
 353err_pclk_disable:
 354        clk_disable_unprepare(keypad->pclk);
 355err_clk:
 356        clk_put(keypad->clk);
 357err_pclk:
 358        clk_put(keypad->pclk);
 359err_iounmap:
 360        iounmap(keypad->reg_base);
 361err_free_mem_region:
 362        release_mem_region(res->start, resource_size(res));
 363err_free_mem:
 364        input_free_device(input);
 365        kfree(keypad);
 366        return error;
 367}
 368
 369static 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
 392static 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
 406static 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
 421static SIMPLE_DEV_PM_OPS(ske_keypad_dev_pm_ops,
 422                         ske_keypad_suspend, ske_keypad_resume);
 423
 424static struct platform_driver ske_keypad_driver = {
 425        .driver = {
 426                .name = "nmk-ske-keypad",
 427                .owner  = THIS_MODULE,
 428                .pm = &ske_keypad_dev_pm_ops,
 429        },
 430        .remove = ske_keypad_remove,
 431};
 432
 433static int __init ske_keypad_init(void)
 434{
 435        return platform_driver_probe(&ske_keypad_driver, ske_keypad_probe);
 436}
 437module_init(ske_keypad_init);
 438
 439static void __exit ske_keypad_exit(void)
 440{
 441        platform_driver_unregister(&ske_keypad_driver);
 442}
 443module_exit(ske_keypad_exit);
 444
 445MODULE_LICENSE("GPL v2");
 446MODULE_AUTHOR("Naveen Kumar <naveen.gaddipati@stericsson.com> / Sundar Iyer <sundar.iyer@stericsson.com>");
 447MODULE_DESCRIPTION("Nomadik Scroll-Key-Encoder Keypad Driver");
 448MODULE_ALIAS("platform:nomadik-ske-keypad");
 449
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.