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/pm.h> 21 #include <linux/input.h> 22 #include <linux/input/matrix_keypad.h> 23 24 #define MAX7359_MAX_KEY_ROWS 8 25 #define MAX7359_MAX_KEY_COLS 8 26 #define MAX7359_MAX_KEY_NUM (MAX7359_MAX_KEY_ROWS * MAX7359_MAX_KEY_COLS) 27 #define MAX7359_ROW_SHIFT 3 28 29 /* 30 * MAX7359 registers 31 */ 32 #define MAX7359_REG_KEYFIFO 0x00 33 #define MAX7359_REG_CONFIG 0x01 34 #define MAX7359_REG_DEBOUNCE 0x02 35 #define MAX7359_REG_INTERRUPT 0x03 36 #define MAX7359_REG_PORTS 0x04 37 #define MAX7359_REG_KEYREP 0x05 38 #define MAX7359_REG_SLEEP 0x06 39 40 /* 41 * Configuration register bits 42 */ 43 #define MAX7359_CFG_SLEEP (1 << 7) 44 #define MAX7359_CFG_INTERRUPT (1 << 5) 45 #define MAX7359_CFG_KEY_RELEASE (1 << 3) 46 #define MAX7359_CFG_WAKEUP (1 << 1) 47 #define MAX7359_CFG_TIMEOUT (1 << 0) 48 49 /* 50 * Autosleep register values (ms) 51 */ 52 #define MAX7359_AUTOSLEEP_8192 0x01 53 #define MAX7359_AUTOSLEEP_4096 0x02 54 #define MAX7359_AUTOSLEEP_2048 0x03 55 #define MAX7359_AUTOSLEEP_1024 0x04 56 #define MAX7359_AUTOSLEEP_512 0x05 57 #define MAX7359_AUTOSLEEP_256 0x06 58 59 struct max7359_keypad { 60 /* matrix key code map */ 61 unsigned short keycodes[MAX7359_MAX_KEY_NUM]; 62 63 struct input_dev *input_dev; 64 struct i2c_client *client; 65 }; 66 67 static int max7359_write_reg(struct i2c_client *client, u8 reg, u8 val) 68 { 69 int ret = i2c_smbus_write_byte_data(client, reg, val); 70 71 if (ret < 0) 72 dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n", 73 __func__, reg, val, ret); 74 return ret; 75 } 76 77 static int max7359_read_reg(struct i2c_client *client, int reg) 78 { 79 int ret = i2c_smbus_read_byte_data(client, reg); 80 81 if (ret < 0) 82 dev_err(&client->dev, "%s: reg 0x%x, err %d\n", 83 __func__, reg, ret); 84 return ret; 85 } 86 87 static void max7359_build_keycode(struct max7359_keypad *keypad, 88 const struct matrix_keymap_data *keymap_data) 89 { 90 struct input_dev *input_dev = keypad->input_dev; 91 int i; 92 93 for (i = 0; i < keymap_data->keymap_size; i++) { 94 unsigned int key = keymap_data->keymap[i]; 95 unsigned int row = KEY_ROW(key); 96 unsigned int col = KEY_COL(key); 97 unsigned int scancode = MATRIX_SCAN_CODE(row, col, 98 MAX7359_ROW_SHIFT); 99 unsigned short keycode = KEY_VAL(key); 100 101 keypad->keycodes[scancode] = keycode; 102 __set_bit(keycode, input_dev->keybit); 103 } 104 __clear_bit(KEY_RESERVED, input_dev->keybit); 105 } 106 107 /* runs in an IRQ thread -- can (and will!) sleep */ 108 static irqreturn_t max7359_interrupt(int irq, void *dev_id) 109 { 110 struct max7359_keypad *keypad = dev_id; 111 struct input_dev *input_dev = keypad->input_dev; 112 int val, row, col, release, code; 113 114 val = max7359_read_reg(keypad->client, MAX7359_REG_KEYFIFO); 115 row = val & 0x7; 116 col = (val >> 3) & 0x7; 117 release = val & 0x40; 118 119 code = MATRIX_SCAN_CODE(row, col, MAX7359_ROW_SHIFT); 120 121 dev_dbg(&keypad->client->dev, 122 "key[%d:%d] %s\n", row, col, release ? "release" : "press"); 123 124 input_event(input_dev, EV_MSC, MSC_SCAN, code); 125 input_report_key(input_dev, keypad->keycodes[code], !release); 126 input_sync(input_dev); 127 128 return IRQ_HANDLED; 129 } 130 131 /* 132 * Let MAX7359 fall into a deep sleep: 133 * If no keys are pressed, enter sleep mode for 8192 ms. And if any 134 * key is pressed, the MAX7359 returns to normal operating mode. 135 */ 136 static inline void max7359_fall_deepsleep(struct i2c_client *client) 137 { 138 max7359_write_reg(client, MAX7359_REG_SLEEP, MAX7359_AUTOSLEEP_8192); 139 } 140 141 /* 142 * Let MAX7359 take a catnap: 143 * Autosleep just for 256 ms. 144 */ 145 static inline void max7359_take_catnap(struct i2c_client *client) 146 { 147 max7359_write_reg(client, MAX7359_REG_SLEEP, MAX7359_AUTOSLEEP_256); 148 } 149 150 static int max7359_open(struct input_dev *dev) 151 { 152 struct max7359_keypad *keypad = input_get_drvdata(dev); 153 154 max7359_take_catnap(keypad->client); 155 156 return 0; 157 } 158 159 static void max7359_close(struct input_dev *dev) 160 { 161 struct max7359_keypad *keypad = input_get_drvdata(dev); 162 163 max7359_fall_deepsleep(keypad->client); 164 } 165 166 static void max7359_initialize(struct i2c_client *client) 167 { 168 max7359_write_reg(client, MAX7359_REG_CONFIG, 169 MAX7359_CFG_INTERRUPT | /* Irq clears after host read */ 170 MAX7359_CFG_KEY_RELEASE | /* Key release enable */ 171 MAX7359_CFG_WAKEUP); /* Key press wakeup enable */ 172 173 /* Full key-scan functionality */ 174 max7359_write_reg(client, MAX7359_REG_DEBOUNCE, 0x1F); 175 176 /* nINT asserts every debounce cycles */ 177 max7359_write_reg(client, MAX7359_REG_INTERRUPT, 0x01); 178 179 max7359_fall_deepsleep(client); 180 } 181 182 static int max7359_probe(struct i2c_client *client, 183 const struct i2c_device_id *id) 184 { 185 const struct matrix_keymap_data *keymap_data = 186 dev_get_platdata(&client->dev); 187 struct max7359_keypad *keypad; 188 struct input_dev *input_dev; 189 int ret; 190 int error; 191 192 if (!client->irq) { 193 dev_err(&client->dev, "The irq number should not be zero\n"); 194 return -EINVAL; 195 } 196 197 /* Detect MAX7359: The initial Keys FIFO value is '0x3F' */ 198 ret = max7359_read_reg(client, MAX7359_REG_KEYFIFO); 199 if (ret < 0) { 200 dev_err(&client->dev, "failed to detect device\n"); 201 return -ENODEV; 202 } 203 204 dev_dbg(&client->dev, "keys FIFO is 0x%02x\n", ret); 205 206 keypad = kzalloc(sizeof(struct max7359_keypad), GFP_KERNEL); 207 input_dev = input_allocate_device(); 208 if (!keypad || !input_dev) { 209 dev_err(&client->dev, "failed to allocate memory\n"); 210 error = -ENOMEM; 211 goto failed_free_mem; 212 } 213 214 keypad->client = client; 215 keypad->input_dev = input_dev; 216 217 input_dev->name = client->name; 218 input_dev->id.bustype = BUS_I2C; 219 input_dev->open = max7359_open; 220 input_dev->close = max7359_close; 221 input_dev->dev.parent = &client->dev; 222 223 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP); 224 input_dev->keycodesize = sizeof(keypad->keycodes[0]); 225 input_dev->keycodemax = ARRAY_SIZE(keypad->keycodes); 226 input_dev->keycode = keypad->keycodes; 227 228 input_set_capability(input_dev, EV_MSC, MSC_SCAN); 229 input_set_drvdata(input_dev, keypad); 230 231 max7359_build_keycode(keypad, keymap_data); 232 233 error = request_threaded_irq(client->irq, NULL, max7359_interrupt, 234 IRQF_TRIGGER_LOW | IRQF_ONESHOT, 235 client->name, keypad); 236 if (error) { 237 dev_err(&client->dev, "failed to register interrupt\n"); 238 goto failed_free_mem; 239 } 240 241 /* Register the input device */ 242 error = input_register_device(input_dev); 243 if (error) { 244 dev_err(&client->dev, "failed to register input device\n"); 245 goto failed_free_irq; 246 } 247 248 /* Initialize MAX7359 */ 249 max7359_initialize(client); 250 251 i2c_set_clientdata(client, keypad); 252 device_init_wakeup(&client->dev, 1); 253 254 return 0; 255 256 failed_free_irq: 257 free_irq(client->irq, keypad); 258 failed_free_mem: 259 input_free_device(input_dev); 260 kfree(keypad); 261 return error; 262 } 263 264 static int max7359_remove(struct i2c_client *client) 265 { 266 struct max7359_keypad *keypad = i2c_get_clientdata(client); 267 268 free_irq(client->irq, keypad); 269 input_unregister_device(keypad->input_dev); 270 kfree(keypad); 271 272 return 0; 273 } 274 275 #ifdef CONFIG_PM_SLEEP 276 static int max7359_suspend(struct device *dev) 277 { 278 struct i2c_client *client = to_i2c_client(dev); 279 280 max7359_fall_deepsleep(client); 281 282 if (device_may_wakeup(&client->dev)) 283 enable_irq_wake(client->irq); 284 285 return 0; 286 } 287 288 static int max7359_resume(struct device *dev) 289 { 290 struct i2c_client *client = to_i2c_client(dev); 291 292 if (device_may_wakeup(&client->dev)) 293 disable_irq_wake(client->irq); 294 295 /* Restore the default setting */ 296 max7359_take_catnap(client); 297 298 return 0; 299 } 300 #endif 301 302 static SIMPLE_DEV_PM_OPS(max7359_pm, max7359_suspend, max7359_resume); 303 304 static const struct i2c_device_id max7359_ids[] = { 305 { "max7359", 0 }, 306 { } 307 }; 308 MODULE_DEVICE_TABLE(i2c, max7359_ids); 309 310 static struct i2c_driver max7359_i2c_driver = { 311 .driver = { 312 .name = "max7359", 313 .pm = &max7359_pm, 314 }, 315 .probe = max7359_probe, 316 .remove = max7359_remove, 317 .id_table = max7359_ids, 318 }; 319 320 module_i2c_driver(max7359_i2c_driver); 321 322 MODULE_AUTHOR("Kim Kyuwon <q1.kim@samsung.com>"); 323 MODULE_DESCRIPTION("MAX7359 Key Switch Controller Driver"); 324 MODULE_LICENSE("GPL v2"); 325