drivers/input/keyboard/spear-keyboard.c

   1 /*
   2  * SPEAr Keyboard Driver
   3  * Based on omap-keypad driver
   4  *
   5  * Copyright (C) 2010 ST Microelectronics
   6  * Rajeev Kumar<rajeev-dlh.kumar@st.com>
   7  *
   8  * This file is licensed under the terms of the GNU General Public
   9  * License version 2. This program is licensed "as is" without any
  10  * warranty of any kind, whether express or implied.
  11  */
  12
  13 #include <linux/clk.h>
  14 #include <linux/errno.h>
  15 #include <linux/init.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/input.h>
  18 #include <linux/io.h>
  19 #include <linux/irq.h>
  20 #include <linux/kernel.h>
  21 #include <linux/module.h>
  22 #include <linux/of.h>
  23 #include <linux/platform_device.h>
  24 #include <linux/pm_wakeup.h>
  25 #include <linux/slab.h>
  26 #include <linux/types.h>
  27 #include <plat/keyboard.h>
  28
  29 /* Keyboard Registers */
  30 #define MODE_CTL_REG    0x00
  31 #define STATUS_REG      0x0C
  32 #define DATA_REG        0x10
  33 #define INTR_MASK       0x54
  34
  35 /* Register Values */
  36 #define NUM_ROWS        16
  37 #define NUM_COLS        16
  38 #define MODE_CTL_PCLK_FREQ_SHIFT        9
  39 #define MODE_CTL_PCLK_FREQ_MSK          0x7F
  40
  41 #define MODE_CTL_KEYBOARD       (0x2 << 0)
  42 #define MODE_CTL_SCAN_RATE_10   (0x0 << 2)
  43 #define MODE_CTL_SCAN_RATE_20   (0x1 << 2)
  44 #define MODE_CTL_SCAN_RATE_40   (0x2 << 2)
  45 #define MODE_CTL_SCAN_RATE_80   (0x3 << 2)
  46 #define MODE_CTL_KEYNUM_SHIFT   6
  47 #define MODE_CTL_START_SCAN     (0x1 << 8)
  48
  49 #define STATUS_DATA_AVAIL       (0x1 << 1)
  50
  51 #define DATA_ROW_MASK           0xF0
  52 #define DATA_COLUMN_MASK        0x0F
  53
  54 #define ROW_SHIFT               4
  55
  56 struct spear_kbd {
  57         struct input_dev *input;
  58         struct resource *res;
  59         void __iomem *io_base;
  60         struct clk *clk;
  61         unsigned int irq;
  62         unsigned int mode;
  63         unsigned short last_key;
  64         unsigned short keycodes[NUM_ROWS * NUM_COLS];
  65         bool rep;
  66         unsigned int suspended_rate;
  67         u32 mode_ctl_reg;
  68 };
  69
  70 static irqreturn_t spear_kbd_interrupt(int irq, void *dev_id)
  71 {
  72         struct spear_kbd *kbd = dev_id;
  73         struct input_dev *input = kbd->input;
  74         unsigned int key;
  75         u32 sts, val;
  76
  77         sts = readl_relaxed(kbd->io_base + STATUS_REG);
  78         if (!(sts & STATUS_DATA_AVAIL))
  79                 return IRQ_NONE;
  80
  81         if (kbd->last_key != KEY_RESERVED) {
  82                 input_report_key(input, kbd->last_key, 0);
  83                 kbd->last_key = KEY_RESERVED;
  84         }
  85
  86         /* following reads active (row, col) pair */
  87         val = readl_relaxed(kbd->io_base + DATA_REG) &
  88                 (DATA_ROW_MASK | DATA_COLUMN_MASK);
  89         key = kbd->keycodes[val];
  90
  91         input_event(input, EV_MSC, MSC_SCAN, val);
  92         input_report_key(input, key, 1);
  93         input_sync(input);
  94
  95         kbd->last_key = key;
  96
  97         /* clear interrupt */
  98         writel_relaxed(0, kbd->io_base + STATUS_REG);
  99
 100         return IRQ_HANDLED;
 101 }
 102
 103 static int spear_kbd_open(struct input_dev *dev)
 104 {
 105         struct spear_kbd *kbd = input_get_drvdata(dev);
 106         int error;
 107         u32 val;
 108
 109         kbd->last_key = KEY_RESERVED;
 110
 111         error = clk_enable(kbd->clk);
 112         if (error)
 113                 return error;
 114
 115         /* keyboard rate to be programmed is input clock (in MHz) - 1 */
 116         val = clk_get_rate(kbd->clk) / 1000000 - 1;
 117         val = (val & MODE_CTL_PCLK_FREQ_MSK) << MODE_CTL_PCLK_FREQ_SHIFT;
 118
 119         /* program keyboard */
 120         val = MODE_CTL_SCAN_RATE_80 | MODE_CTL_KEYBOARD | val |
 121                 (kbd->mode << MODE_CTL_KEYNUM_SHIFT);
 122         writel_relaxed(val, kbd->io_base + MODE_CTL_REG);
 123         writel_relaxed(1, kbd->io_base + STATUS_REG);
 124
 125         /* start key scan */
 126         val = readl_relaxed(kbd->io_base + MODE_CTL_REG);
 127         val |= MODE_CTL_START_SCAN;
 128         writel_relaxed(val, kbd->io_base + MODE_CTL_REG);
 129
 130         return 0;
 131 }
 132
 133 static void spear_kbd_close(struct input_dev *dev)
 134 {
 135         struct spear_kbd *kbd = input_get_drvdata(dev);
 136         u32 val;
 137
 138         /* stop key scan */
 139         val = readl_relaxed(kbd->io_base + MODE_CTL_REG);
 140         val &= ~MODE_CTL_START_SCAN;
 141         writel_relaxed(val, kbd->io_base + MODE_CTL_REG);
 142
 143         clk_disable(kbd->clk);
 144
 145         kbd->last_key = KEY_RESERVED;
 146 }
 147
 148 #ifdef CONFIG_OF
 149 static int __devinit spear_kbd_parse_dt(struct platform_device *pdev,
 150                                         struct spear_kbd *kbd)
 151 {
 152         struct device_node *np = pdev->dev.of_node;
 153         int error;
 154         u32 val, suspended_rate;
 155
 156         if (!np) {
 157                 dev_err(&pdev->dev, "Missing DT data\n");
 158                 return -EINVAL;
 159         }
 160
 161         if (of_property_read_bool(np, "autorepeat"))
 162                 kbd->rep = true;
 163
 164         if (of_property_read_u32(np, "suspended_rate", &suspended_rate))
 165                 kbd->suspended_rate = suspended_rate;
 166
 167         error = of_property_read_u32(np, "st,mode", &val);
 168         if (error) {
 169                 dev_err(&pdev->dev, "DT: Invalid or missing mode\n");
 170                 return error;
 171         }
 172
 173         kbd->mode = val;
 174         return 0;
 175 }
 176 #else
 177 static inline int spear_kbd_parse_dt(struct platform_device *pdev,
 178                                      struct spear_kbd *kbd)
 179 {
 180         return -ENOSYS;
 181 }
 182 #endif
 183
 184 static int __devinit spear_kbd_probe(struct platform_device *pdev)
 185 {
 186         struct kbd_platform_data *pdata = dev_get_platdata(&pdev->dev);
 187         const struct matrix_keymap_data *keymap = pdata ? pdata->keymap : NULL;
 188         struct spear_kbd *kbd;
 189         struct input_dev *input_dev;
 190         struct resource *res;
 191         int irq;
 192         int error;
 193
 194         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 195         if (!res) {
 196                 dev_err(&pdev->dev, "no keyboard resource defined\n");
 197                 return -EBUSY;
 198         }
 199
 200         irq = platform_get_irq(pdev, 0);
 201         if (irq < 0) {
 202                 dev_err(&pdev->dev, "not able to get irq for the device\n");
 203                 return irq;
 204         }
 205
 206         kbd = kzalloc(sizeof(*kbd), GFP_KERNEL);
 207         input_dev = input_allocate_device();
 208         if (!kbd || !input_dev) {
 209                 dev_err(&pdev->dev, "out of memory\n");
 210                 error = -ENOMEM;
 211                 goto err_free_mem;
 212         }
 213
 214         kbd->input = input_dev;
 215         kbd->irq = irq;
 216
 217         if (!pdata) {
 218                 error = spear_kbd_parse_dt(pdev, kbd);
 219                 if (error)
 220                         goto err_free_mem;
 221         } else {
 222                 kbd->mode = pdata->mode;
 223                 kbd->rep = pdata->rep;
 224                 kbd->suspended_rate = pdata->suspended_rate;
 225         }
 226
 227         kbd->res = request_mem_region(res->start, resource_size(res),
 228                                       pdev->name);
 229         if (!kbd->res) {
 230                 dev_err(&pdev->dev, "keyboard region already claimed\n");
 231                 error = -EBUSY;
 232                 goto err_free_mem;
 233         }
 234
 235         kbd->io_base = ioremap(res->start, resource_size(res));
 236         if (!kbd->io_base) {
 237                 dev_err(&pdev->dev, "ioremap failed for kbd_region\n");
 238                 error = -ENOMEM;
 239                 goto err_release_mem_region;
 240         }
 241
 242         kbd->clk = clk_get(&pdev->dev, NULL);
 243         if (IS_ERR(kbd->clk)) {
 244                 error = PTR_ERR(kbd->clk);
 245                 goto err_iounmap;
 246         }
 247
 248         input_dev->name = "Spear Keyboard";
 249         input_dev->phys = "keyboard/input0";
 250         input_dev->dev.parent = &pdev->dev;
 251         input_dev->id.bustype = BUS_HOST;
 252         input_dev->id.vendor = 0x0001;
 253         input_dev->id.product = 0x0001;
 254         input_dev->id.version = 0x0100;
 255         input_dev->open = spear_kbd_open;
 256         input_dev->close = spear_kbd_close;
 257
 258         error = matrix_keypad_build_keymap(keymap, NULL, NUM_ROWS, NUM_COLS,
 259                                            kbd->keycodes, input_dev);
 260         if (error) {
 261                 dev_err(&pdev->dev, "Failed to build keymap\n");
 262                 goto err_put_clk;
 263         }
 264
 265         if (kbd->rep)
 266                 __set_bit(EV_REP, input_dev->evbit);
 267         input_set_capability(input_dev, EV_MSC, MSC_SCAN);
 268
 269         input_set_drvdata(input_dev, kbd);
 270
 271         error = request_irq(irq, spear_kbd_interrupt, 0, "keyboard", kbd);
 272         if (error) {
 273                 dev_err(&pdev->dev, "request_irq fail\n");
 274                 goto err_put_clk;
 275         }
 276
 277         error = input_register_device(input_dev);
 278         if (error) {
 279                 dev_err(&pdev->dev, "Unable to register keyboard device\n");
 280                 goto err_free_irq;
 281         }
 282
 283         device_init_wakeup(&pdev->dev, 1);
 284         platform_set_drvdata(pdev, kbd);
 285
 286         return 0;
 287
 288 err_free_irq:
 289         free_irq(kbd->irq, kbd);
 290 err_put_clk:
 291         clk_put(kbd->clk);
 292 err_iounmap:
 293         iounmap(kbd->io_base);
 294 err_release_mem_region:
 295         release_mem_region(res->start, resource_size(res));
 296 err_free_mem:
 297         input_free_device(input_dev);
 298         kfree(kbd);
 299
 300         return error;
 301 }
 302
 303 static int __devexit spear_kbd_remove(struct platform_device *pdev)
 304 {
 305         struct spear_kbd *kbd = platform_get_drvdata(pdev);
 306
 307         free_irq(kbd->irq, kbd);
 308         input_unregister_device(kbd->input);
 309         clk_put(kbd->clk);
 310         iounmap(kbd->io_base);
 311         release_mem_region(kbd->res->start, resource_size(kbd->res));
 312         kfree(kbd);
 313
 314         device_init_wakeup(&pdev->dev, 0);
 315         platform_set_drvdata(pdev, NULL);
 316
 317         return 0;
 318 }
 319
 320 #ifdef CONFIG_PM
 321 static int spear_kbd_suspend(struct device *dev)
 322 {
 323         struct platform_device *pdev = to_platform_device(dev);
 324         struct spear_kbd *kbd = platform_get_drvdata(pdev);
 325         struct input_dev *input_dev = kbd->input;
 326         unsigned int rate = 0, mode_ctl_reg, val;
 327
 328         mutex_lock(&input_dev->mutex);
 329
 330         /* explicitly enable clock as we may program device */
 331         clk_enable(kbd->clk);
 332
 333         mode_ctl_reg = readl_relaxed(kbd->io_base + MODE_CTL_REG);
 334
 335         if (device_may_wakeup(&pdev->dev)) {
 336                 enable_irq_wake(kbd->irq);
 337
 338                 /*
 339                  * reprogram the keyboard operating frequency as on some
 340                  * platform it may change during system suspended
 341                  */
 342                 if (kbd->suspended_rate)
 343                         rate = kbd->suspended_rate / 1000000 - 1;
 344                 else
 345                         rate = clk_get_rate(kbd->clk) / 1000000 - 1;
 346
 347                 val = mode_ctl_reg &
 348                         ~(MODE_CTL_PCLK_FREQ_MSK << MODE_CTL_PCLK_FREQ_SHIFT);
 349                 val |= (rate & MODE_CTL_PCLK_FREQ_MSK)
 350                         << MODE_CTL_PCLK_FREQ_SHIFT;
 351                 writel_relaxed(val, kbd->io_base + MODE_CTL_REG);
 352
 353         } else {
 354                 if (input_dev->users) {
 355                         writel_relaxed(mode_ctl_reg & ~MODE_CTL_START_SCAN,
 356                                         kbd->io_base + MODE_CTL_REG);
 357                         clk_disable(kbd->clk);
 358                 }
 359         }
 360
 361         /* store current configuration */
 362         if (input_dev->users)
 363                 kbd->mode_ctl_reg = mode_ctl_reg;
 364
 365         /* restore previous clk state */
 366         clk_disable(kbd->clk);
 367
 368         mutex_unlock(&input_dev->mutex);
 369
 370         return 0;
 371 }
 372
 373 static int spear_kbd_resume(struct device *dev)
 374 {
 375         struct platform_device *pdev = to_platform_device(dev);
 376         struct spear_kbd *kbd = platform_get_drvdata(pdev);
 377         struct input_dev *input_dev = kbd->input;
 378
 379         mutex_lock(&input_dev->mutex);
 380
 381         if (device_may_wakeup(&pdev->dev)) {
 382                 disable_irq_wake(kbd->irq);
 383         } else {
 384                 if (input_dev->users)
 385                         clk_enable(kbd->clk);
 386         }
 387
 388         /* restore current configuration */
 389         if (input_dev->users)
 390                 writel_relaxed(kbd->mode_ctl_reg, kbd->io_base + MODE_CTL_REG);
 391
 392         mutex_unlock(&input_dev->mutex);
 393
 394         return 0;
 395 }
 396 #endif
 397
 398 static SIMPLE_DEV_PM_OPS(spear_kbd_pm_ops, spear_kbd_suspend, spear_kbd_resume);
 399
 400 #ifdef CONFIG_OF
 401 static const struct of_device_id spear_kbd_id_table[] = {
 402         { .compatible = "st,spear300-kbd" },
 403         {}
 404 };
 405 MODULE_DEVICE_TABLE(of, spear_kbd_id_table);
 406 #endif
 407
 408 static struct platform_driver spear_kbd_driver = {
 409         .probe          = spear_kbd_probe,
 410         .remove         = __devexit_p(spear_kbd_remove),
 411         .driver         = {
 412                 .name   = "keyboard",
 413                 .owner  = THIS_MODULE,
 414                 .pm     = &spear_kbd_pm_ops,
 415                 .of_match_table = of_match_ptr(spear_kbd_id_table),
 416         },
 417 };
 418 module_platform_driver(spear_kbd_driver);
 419
 420 MODULE_AUTHOR("Rajeev Kumar");
 421 MODULE_DESCRIPTION("SPEAr Keyboard Driver");
 422 MODULE_LICENSE("GPL");