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 /* runs in an IRQ thread -- can (and will!) sleep */ 88 static irqreturn_t max7359_interrupt(int irq, void *dev_id) 89 { 90 struct max7359_keypad *keypad = dev_id; 91 struct input_dev *input_dev = keypad->input_dev; 92 int val, row, col, release, code; 93 94 val = max7359_read_reg(keypad->client, MAX7359_REG_KEYFIFO); 95 row = val & 0x7; 96 col = (val >> 3) & 0x7; 97 release = val & 0x40; 98 99 code = MATRIX_SCAN_CODE(row, col, MAX7359_ROW_SHIFT); 100 101 dev_dbg(&keypad->client->dev, 102 "key[%d:%d] %s\n", row, col, release ? "release" : "press"); 103 104 input_event(input_dev, EV_MSC, MSC_SCAN, code); 105 input_report_key(input_dev, keypad->keycodes[code], !release); 106 input_sync(input_dev); 107 108 return IRQ_HANDLED; 109 } 110 111 /* 112 * Let MAX7359 fall into a deep sleep: 113 * If no keys are pressed, enter sleep mode for 8192 ms. And if any 114 * key is pressed, the MAX7359 returns to normal operating mode. 115 */ 116 static inline void max7359_fall_deepsleep(struct i2c_client *client) 117 { 118 max7359_write_reg(client, MAX7359_REG_SLEEP, MAX7359_AUTOSLEEP_8192); 119 } 120 121 /* 122 * Let MAX7359 take a catnap: 123 * Autosleep just for 256 ms. 124 */ 125 static inline void max7359_take_catnap(struct i2c_client *client) 126 { 127 max7359_write_reg(client, MAX7359_REG_SLEEP, MAX7359_AUTOSLEEP_256); 128 } 129 130 static int max7359_open(struct input_dev *dev) 131 { 132 struct max7359_keypad *keypad = input_get_drvdata(dev); 133 134 max7359_take_catnap(keypad->client); 135 136 return 0; 137 } 138 139 static void max7359_close(struct input_dev *dev) 140 { 141 struct max7359_keypad *keypad = input_get_drvdata(dev); 142 143 max7359_fall_deepsleep(keypad->client); 144 } 145 146 static void max7359_initialize(struct i2c_client *client) 147 { 148 max7359_write_reg(client, MAX7359_REG_CONFIG, 149 MAX7359_CFG_KEY_RELEASE | /* Key release enable */ 150 MAX7359_CFG_WAKEUP); /* Key press wakeup enable */ 151 152 /* Full key-scan functionality */ 153 max7359_write_reg(client, MAX7359_REG_DEBOUNCE, 0x1F); 154 155 /* nINT asserts every debounce cycles */ 156 max7359_write_reg(client, MAX7359_REG_INTERRUPT, 0x01); 157 158 max7359_fall_deepsleep(client); 159 } 160 161 static int max7359_probe(struct i2c_client *client, 162 const struct i2c_device_id *id) 163 { 164 const struct matrix_keymap_data *keymap_data = 165 dev_get_platdata(&client->dev); 166 struct max7359_keypad *keypad; 167 struct input_dev *input_dev; 168 int ret; 169 int error; 170 171 if (!client->irq) { 172 dev_err(&client->dev, "The irq number should not be zero\n"); 173 return -EINVAL; 174 } 175 176 /* Detect MAX7359: The initial Keys FIFO value is '0x3F' */ 177 ret = max7359_read_reg(client, MAX7359_REG_KEYFIFO); 178 if (ret < 0) { 179 dev_err(&client->dev, "failed to detect device\n"); 180 return -ENODEV; 181 } 182 183 dev_dbg(&client->dev, "keys FIFO is 0x%02x\n", ret); 184 185 keypad = devm_kzalloc(&client->dev, sizeof(struct max7359_keypad), 186 GFP_KERNEL); 187 if (!keypad) { 188 dev_err(&client->dev, "failed to allocate memory\n"); 189 return -ENOMEM; 190 } 191 192 input_dev = devm_input_allocate_device(&client->dev); 193 if (!input_dev) { 194 dev_err(&client->dev, "failed to allocate input device\n"); 195 return -ENOMEM; 196 } 197 198 keypad->client = client; 199 keypad->input_dev = input_dev; 200 201 input_dev->name = client->name; 202 input_dev->id.bustype = BUS_I2C; 203 input_dev->open = max7359_open; 204 input_dev->close = max7359_close; 205 input_dev->dev.parent = &client->dev; 206 207 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP); 208 input_dev->keycodesize = sizeof(keypad->keycodes[0]); 209 input_dev->keycodemax = ARRAY_SIZE(keypad->keycodes); 210 input_dev->keycode = keypad->keycodes; 211 212 input_set_capability(input_dev, EV_MSC, MSC_SCAN); 213 input_set_drvdata(input_dev, keypad); 214 215 error = matrix_keypad_build_keymap(keymap_data, NULL, 216 MAX7359_MAX_KEY_ROWS, 217 MAX7359_MAX_KEY_COLS, 218 keypad->keycodes, 219 input_dev); 220 if (error) { 221 dev_err(&client->dev, "failed to build keymap\n"); 222 return error; 223 } 224 225 error = devm_request_threaded_irq(&client->dev, client->irq, NULL, 226 max7359_interrupt, 227 IRQF_TRIGGER_LOW | IRQF_ONESHOT, 228 client->name, keypad); 229 if (error) { 230 dev_err(&client->dev, "failed to register interrupt\n"); 231 return error; 232 } 233 234 /* Register the input device */ 235 error = input_register_device(input_dev); 236 if (error) { 237 dev_err(&client->dev, "failed to register input device\n"); 238 return error; 239 } 240 241 /* Initialize MAX7359 */ 242 max7359_initialize(client); 243 244 i2c_set_clientdata(client, keypad); 245 device_init_wakeup(&client->dev, 1); 246 247 return 0; 248 } 249 250 #ifdef CONFIG_PM_SLEEP 251 static int max7359_suspend(struct device *dev) 252 { 253 struct i2c_client *client = to_i2c_client(dev); 254 255 max7359_fall_deepsleep(client); 256 257 if (device_may_wakeup(&client->dev)) 258 enable_irq_wake(client->irq); 259 260 return 0; 261 } 262 263 static int max7359_resume(struct device *dev) 264 { 265 struct i2c_client *client = to_i2c_client(dev); 266 267 if (device_may_wakeup(&client->dev)) 268 disable_irq_wake(client->irq); 269 270 /* Restore the default setting */ 271 max7359_take_catnap(client); 272 273 return 0; 274 } 275 #endif 276 277 static SIMPLE_DEV_PM_OPS(max7359_pm, max7359_suspend, max7359_resume); 278 279 static const struct i2c_device_id max7359_ids[] = { 280 { "max7359", 0 }, 281 { } 282 }; 283 MODULE_DEVICE_TABLE(i2c, max7359_ids); 284 285 static struct i2c_driver max7359_i2c_driver = { 286 .driver = { 287 .name = "max7359", 288 .pm = &max7359_pm, 289 }, 290 .probe = max7359_probe, 291 .id_table = max7359_ids, 292 }; 293 294 module_i2c_driver(max7359_i2c_driver); 295 296 MODULE_AUTHOR("Kim Kyuwon <q1.kim@samsung.com>"); 297 MODULE_DESCRIPTION("MAX7359 Key Switch Controller Driver"); 298 MODULE_LICENSE("GPL v2"); 299