drivers/input/keyboard/max7359_keypad.c

   1 /*
   2  * max7359_keypad.c - MAX7359 Key Switch Controller Driver
   3  *
   4  * Copyright (C) 2009 Samsung Electronics
   5  * Kim Kyuwon <q1.kim@samsung.com>
   6  *
   7  * Based on pxa27x_keypad.c
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  *
  13  * Datasheet: http://www.maxim-ic.com/quick_view2.cfm/qv_pk/5456
  14  */
  15
  16 #include <linux/module.h>
  17 #include <linux/i2c.h>
  18 #include <linux/slab.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/input.h>
  21 #include <linux/input/matrix_keypad.h>
  22
  23 #define MAX7359_MAX_KEY_ROWS    8
  24 #define MAX7359_MAX_KEY_COLS    8
  25 #define MAX7359_MAX_KEY_NUM     (MAX7359_MAX_KEY_ROWS * MAX7359_MAX_KEY_COLS)
  26 #define MAX7359_ROW_SHIFT       3
  27
  28 /*
  29  * MAX7359 registers
  30  */
  31 #define MAX7359_REG_KEYFIFO     0x00
  32 #define MAX7359_REG_CONFIG      0x01
  33 #define MAX7359_REG_DEBOUNCE    0x02
  34 #define MAX7359_REG_INTERRUPT   0x03
  35 #define MAX7359_REG_PORTS       0x04
  36 #define MAX7359_REG_KEYREP      0x05
  37 #define MAX7359_REG_SLEEP       0x06
  38
  39 /*
  40  * Configuration register bits
  41  */
  42 #define MAX7359_CFG_SLEEP       (1 << 7)
  43 #define MAX7359_CFG_INTERRUPT   (1 << 5)
  44 #define MAX7359_CFG_KEY_RELEASE (1 << 3)
  45 #define MAX7359_CFG_WAKEUP      (1 << 1)
  46 #define MAX7359_CFG_TIMEOUT     (1 << 0)
  47
  48 /*
  49  * Autosleep register values (ms)
  50  */
  51 #define MAX7359_AUTOSLEEP_8192  0x01
  52 #define MAX7359_AUTOSLEEP_4096  0x02
  53 #define MAX7359_AUTOSLEEP_2048  0x03
  54 #define MAX7359_AUTOSLEEP_1024  0x04
  55 #define MAX7359_AUTOSLEEP_512   0x05
  56 #define MAX7359_AUTOSLEEP_256   0x06
  57
  58 struct max7359_keypad {
  59         /* matrix key code map */
  60         unsigned short keycodes[MAX7359_MAX_KEY_NUM];
  61
  62         struct input_dev *input_dev;
  63         struct i2c_client *client;
  64 };
  65
  66 static int max7359_write_reg(struct i2c_client *client, u8 reg, u8 val)
  67 {
  68         int ret = i2c_smbus_write_byte_data(client, reg, val);
  69
  70         if (ret < 0)
  71                 dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
  72                         __func__, reg, val, ret);
  73         return ret;
  74 }
  75
  76 static int max7359_read_reg(struct i2c_client *client, int reg)
  77 {
  78         int ret = i2c_smbus_read_byte_data(client, reg);
  79
  80         if (ret < 0)
  81                 dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
  82                         __func__, reg, ret);
  83         return ret;
  84 }
  85
  86 static void max7359_build_keycode(struct max7359_keypad *keypad,
  87                                 const struct matrix_keymap_data *keymap_data)
  88 {
  89         struct input_dev *input_dev = keypad->input_dev;
  90         int i;
  91
  92         for (i = 0; i < keymap_data->keymap_size; i++) {
  93                 unsigned int key = keymap_data->keymap[i];
  94                 unsigned int row = KEY_ROW(key);
  95                 unsigned int col = KEY_COL(key);
  96                 unsigned int scancode = MATRIX_SCAN_CODE(row, col,
  97                                                 MAX7359_ROW_SHIFT);
  98                 unsigned short keycode = KEY_VAL(key);
  99
 100                 keypad->keycodes[scancode] = keycode;
 101                 __set_bit(keycode, input_dev->keybit);
 102         }
 103         __clear_bit(KEY_RESERVED, input_dev->keybit);
 104 }
 105
 106 /* runs in an IRQ thread -- can (and will!) sleep */
 107 static irqreturn_t max7359_interrupt(int irq, void *dev_id)
 108 {
 109         struct max7359_keypad *keypad = dev_id;
 110         struct input_dev *input_dev = keypad->input_dev;
 111         int val, row, col, release, code;
 112
 113         val = max7359_read_reg(keypad->client, MAX7359_REG_KEYFIFO);
 114         row = val & 0x7;
 115         col = (val >> 3) & 0x7;
 116         release = val & 0x40;
 117
 118         code = MATRIX_SCAN_CODE(row, col, MAX7359_ROW_SHIFT);
 119
 120         dev_dbg(&keypad->client->dev,
 121                 "key[%d:%d] %s\n", row, col, release ? "release" : "press");
 122
 123         input_event(input_dev, EV_MSC, MSC_SCAN, code);
 124         input_report_key(input_dev, keypad->keycodes[code], !release);
 125         input_sync(input_dev);
 126
 127         return IRQ_HANDLED;
 128 }
 129
 130 /*
 131  * Let MAX7359 fall into a deep sleep:
 132  * If no keys are pressed, enter sleep mode for 8192 ms. And if any
 133  * key is pressed, the MAX7359 returns to normal operating mode.
 134  */
 135 static inline void max7359_fall_deepsleep(struct i2c_client *client)
 136 {
 137         max7359_write_reg(client, MAX7359_REG_SLEEP, MAX7359_AUTOSLEEP_8192);
 138 }
 139
 140 /*
 141  * Let MAX7359 take a catnap:
 142  * Autosleep just for 256 ms.
 143  */
 144 static inline void max7359_take_catnap(struct i2c_client *client)
 145 {
 146         max7359_write_reg(client, MAX7359_REG_SLEEP, MAX7359_AUTOSLEEP_256);
 147 }
 148
 149 static int max7359_open(struct input_dev *dev)
 150 {
 151         struct max7359_keypad *keypad = input_get_drvdata(dev);
 152
 153         max7359_take_catnap(keypad->client);
 154
 155         return 0;
 156 }
 157
 158 static void max7359_close(struct input_dev *dev)
 159 {
 160         struct max7359_keypad *keypad = input_get_drvdata(dev);
 161
 162         max7359_fall_deepsleep(keypad->client);
 163 }
 164
 165 static void max7359_initialize(struct i2c_client *client)
 166 {
 167         max7359_write_reg(client, MAX7359_REG_CONFIG,
 168                 MAX7359_CFG_INTERRUPT | /* Irq clears after host read */
 169                 MAX7359_CFG_KEY_RELEASE | /* Key release enable */
 170                 MAX7359_CFG_WAKEUP); /* Key press wakeup enable */
 171
 172         /* Full key-scan functionality */
 173         max7359_write_reg(client, MAX7359_REG_DEBOUNCE, 0x1F);
 174
 175         /* nINT asserts every debounce cycles */
 176         max7359_write_reg(client, MAX7359_REG_INTERRUPT, 0x01);
 177
 178         max7359_fall_deepsleep(client);
 179 }
 180
 181 static int __devinit max7359_probe(struct i2c_client *client,
 182                                         const struct i2c_device_id *id)
 183 {
 184         const struct matrix_keymap_data *keymap_data = client->dev.platform_data;
 185         struct max7359_keypad *keypad;
 186         struct input_dev *input_dev;
 187         int ret;
 188         int error;
 189
 190         if (!client->irq) {
 191                 dev_err(&client->dev, "The irq number should not be zero\n");
 192                 return -EINVAL;
 193         }
 194
 195         /* Detect MAX7359: The initial Keys FIFO value is '0x3F' */
 196         ret = max7359_read_reg(client, MAX7359_REG_KEYFIFO);
 197         if (ret < 0) {
 198                 dev_err(&client->dev, "failed to detect device\n");
 199                 return -ENODEV;
 200         }
 201
 202         dev_dbg(&client->dev, "keys FIFO is 0x%02x\n", ret);
 203
 204         keypad = kzalloc(sizeof(struct max7359_keypad), GFP_KERNEL);
 205         input_dev = input_allocate_device();
 206         if (!keypad || !input_dev) {
 207                 dev_err(&client->dev, "failed to allocate memory\n");
 208                 error = -ENOMEM;
 209                 goto failed_free_mem;
 210         }
 211
 212         keypad->client = client;
 213         keypad->input_dev = input_dev;
 214
 215         input_dev->name = client->name;
 216         input_dev->id.bustype = BUS_I2C;
 217         input_dev->open = max7359_open;
 218         input_dev->close = max7359_close;
 219         input_dev->dev.parent = &client->dev;
 220
 221         input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP);
 222         input_dev->keycodesize = sizeof(keypad->keycodes[0]);
 223         input_dev->keycodemax = ARRAY_SIZE(keypad->keycodes);
 224         input_dev->keycode = keypad->keycodes;
 225
 226         input_set_capability(input_dev, EV_MSC, MSC_SCAN);
 227         input_set_drvdata(input_dev, keypad);
 228
 229         max7359_build_keycode(keypad, keymap_data);
 230
 231         error = request_threaded_irq(client->irq, NULL, max7359_interrupt,
 232                                      IRQF_TRIGGER_LOW | IRQF_ONESHOT,
 233                                      client->name, keypad);
 234         if (error) {
 235                 dev_err(&client->dev, "failed to register interrupt\n");
 236                 goto failed_free_mem;
 237         }
 238
 239         /* Register the input device */
 240         error = input_register_device(input_dev);
 241         if (error) {
 242                 dev_err(&client->dev, "failed to register input device\n");
 243                 goto failed_free_irq;
 244         }
 245
 246         /* Initialize MAX7359 */
 247         max7359_initialize(client);
 248
 249         i2c_set_clientdata(client, keypad);
 250         device_init_wakeup(&client->dev, 1);
 251
 252         return 0;
 253
 254 failed_free_irq:
 255         free_irq(client->irq, keypad);
 256 failed_free_mem:
 257         input_free_device(input_dev);
 258         kfree(keypad);
 259         return error;
 260 }
 261
 262 static int __devexit max7359_remove(struct i2c_client *client)
 263 {
 264         struct max7359_keypad *keypad = i2c_get_clientdata(client);
 265
 266         free_irq(client->irq, keypad);
 267         input_unregister_device(keypad->input_dev);
 268         kfree(keypad);
 269
 270         return 0;
 271 }
 272
 273 #ifdef CONFIG_PM
 274 static int max7359_suspend(struct i2c_client *client, pm_message_t mesg)
 275 {
 276         max7359_fall_deepsleep(client);
 277
 278         if (device_may_wakeup(&client->dev))
 279                 enable_irq_wake(client->irq);
 280
 281         return 0;
 282 }
 283
 284 static int max7359_resume(struct i2c_client *client)
 285 {
 286         if (device_may_wakeup(&client->dev))
 287                 disable_irq_wake(client->irq);
 288
 289         /* Restore the default setting */
 290         max7359_take_catnap(client);
 291
 292         return 0;
 293 }
 294 #else
 295 #define max7359_suspend NULL
 296 #define max7359_resume  NULL
 297 #endif
 298
 299 static const struct i2c_device_id max7359_ids[] = {
 300         { "max7359", 0 },
 301         { }
 302 };
 303 MODULE_DEVICE_TABLE(i2c, max7359_ids);
 304
 305 static struct i2c_driver max7359_i2c_driver = {
 306         .driver = {
 307                 .name = "max7359",
 308         },
 309         .probe          = max7359_probe,
 310         .remove         = __devexit_p(max7359_remove),
 311         .suspend        = max7359_suspend,
 312         .resume         = max7359_resume,
 313         .id_table       = max7359_ids,
 314 };
 315
 316 static int __init max7359_init(void)
 317 {
 318         return i2c_add_driver(&max7359_i2c_driver);
 319 }
 320 module_init(max7359_init);
 321
 322 static void __exit max7359_exit(void)
 323 {
 324         i2c_del_driver(&max7359_i2c_driver);
 325 }
 326 module_exit(max7359_exit);
 327
 328 MODULE_AUTHOR("Kim Kyuwon <q1.kim@samsung.com>");
 329 MODULE_DESCRIPTION("MAX7359 Key Switch Controller Driver");
 330 MODULE_LICENSE("GPL v2");