drivers/input/keyboard/mcs_touchkey.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Touchkey driver for MELFAS MCS5000/5080 controller
   4  *
   5  * Copyright (C) 2010 Samsung Electronics Co.Ltd
   6  * Author: HeungJun Kim <[email protected]>
   7  * Author: Joonyoung Shim <[email protected]>
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/i2c.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/input.h>
  14 #include <linux/irq.h>
  15 #include <linux/slab.h>
  16 #include <linux/platform_data/mcs.h>
  17 #include <linux/pm.h>
  18
  19 /* MCS5000 Touchkey */
  20 #define MCS5000_TOUCHKEY_STATUS         0x04
  21 #define MCS5000_TOUCHKEY_STATUS_PRESS   7
  22 #define MCS5000_TOUCHKEY_FW             0x0a
  23 #define MCS5000_TOUCHKEY_BASE_VAL       0x61
  24
  25 /* MCS5080 Touchkey */
  26 #define MCS5080_TOUCHKEY_STATUS         0x00
  27 #define MCS5080_TOUCHKEY_STATUS_PRESS   3
  28 #define MCS5080_TOUCHKEY_FW             0x01
  29 #define MCS5080_TOUCHKEY_BASE_VAL       0x1
  30
  31 enum mcs_touchkey_type {
  32         MCS5000_TOUCHKEY,
  33         MCS5080_TOUCHKEY,
  34 };
  35
  36 struct mcs_touchkey_chip {
  37         unsigned int status_reg;
  38         unsigned int pressbit;
  39         unsigned int press_invert;
  40         unsigned int baseval;
  41 };
  42
  43 struct mcs_touchkey_data {
  44         void (*poweron)(bool);
  45
  46         struct i2c_client *client;
  47         struct input_dev *input_dev;
  48         struct mcs_touchkey_chip chip;
  49         unsigned int key_code;
  50         unsigned int key_val;
  51         unsigned short keycodes[];
  52 };
  53
  54 static irqreturn_t mcs_touchkey_interrupt(int irq, void *dev_id)
  55 {
  56         struct mcs_touchkey_data *data = dev_id;
  57         struct mcs_touchkey_chip *chip = &data->chip;
  58         struct i2c_client *client = data->client;
  59         struct input_dev *input = data->input_dev;
  60         unsigned int key_val;
  61         unsigned int pressed;
  62         int val;
  63
  64         val = i2c_smbus_read_byte_data(client, chip->status_reg);
  65         if (val < 0) {
  66                 dev_err(&client->dev, "i2c read error [%d]\n", val);
  67                 goto out;
  68         }
  69
  70         pressed = (val & (1 << chip->pressbit)) >> chip->pressbit;
  71         if (chip->press_invert)
  72                 pressed ^= chip->press_invert;
  73
  74         /* key_val is 0 when released, so we should use key_val of press. */
  75         if (pressed) {
  76                 key_val = val & (0xff >> (8 - chip->pressbit));
  77                 if (!key_val)
  78                         goto out;
  79                 key_val -= chip->baseval;
  80                 data->key_code = data->keycodes[key_val];
  81                 data->key_val = key_val;
  82         }
  83
  84         input_event(input, EV_MSC, MSC_SCAN, data->key_val);
  85         input_report_key(input, data->key_code, pressed);
  86         input_sync(input);
  87
  88         dev_dbg(&client->dev, "key %d %d %s\n", data->key_val, data->key_code,
  89                 pressed ? "pressed" : "released");
  90
  91  out:
  92         return IRQ_HANDLED;
  93 }
  94
  95 static int mcs_touchkey_probe(struct i2c_client *client)
  96 {
  97         const struct i2c_device_id *id = i2c_client_get_device_id(client);
  98         const struct mcs_platform_data *pdata;
  99         struct mcs_touchkey_data *data;
 100         struct input_dev *input_dev;
 101         unsigned int fw_reg;
 102         int fw_ver;
 103         int error;
 104         int i;
 105
 106         pdata = dev_get_platdata(&client->dev);
 107         if (!pdata) {
 108                 dev_err(&client->dev, "no platform data defined\n");
 109                 return -EINVAL;
 110         }
 111
 112         data = kzalloc(struct_size(data, keycodes, pdata->key_maxval + 1),
 113                        GFP_KERNEL);
 114         input_dev = input_allocate_device();
 115         if (!data || !input_dev) {
 116                 dev_err(&client->dev, "Failed to allocate memory\n");
 117                 error = -ENOMEM;
 118                 goto err_free_mem;
 119         }
 120
 121         data->client = client;
 122         data->input_dev = input_dev;
 123
 124         if (id->driver_data == MCS5000_TOUCHKEY) {
 125                 data->chip.status_reg = MCS5000_TOUCHKEY_STATUS;
 126                 data->chip.pressbit = MCS5000_TOUCHKEY_STATUS_PRESS;
 127                 data->chip.baseval = MCS5000_TOUCHKEY_BASE_VAL;
 128                 fw_reg = MCS5000_TOUCHKEY_FW;
 129         } else {
 130                 data->chip.status_reg = MCS5080_TOUCHKEY_STATUS;
 131                 data->chip.pressbit = MCS5080_TOUCHKEY_STATUS_PRESS;
 132                 data->chip.press_invert = 1;
 133                 data->chip.baseval = MCS5080_TOUCHKEY_BASE_VAL;
 134                 fw_reg = MCS5080_TOUCHKEY_FW;
 135         }
 136
 137         fw_ver = i2c_smbus_read_byte_data(client, fw_reg);
 138         if (fw_ver < 0) {
 139                 error = fw_ver;
 140                 dev_err(&client->dev, "i2c read error[%d]\n", error);
 141                 goto err_free_mem;
 142         }
 143         dev_info(&client->dev, "Firmware version: %d\n", fw_ver);
 144
 145         input_dev->name = "MELFAS MCS Touchkey";
 146         input_dev->id.bustype = BUS_I2C;
 147         input_dev->dev.parent = &client->dev;
 148         input_dev->evbit[0] = BIT_MASK(EV_KEY);
 149         if (!pdata->no_autorepeat)
 150                 input_dev->evbit[0] |= BIT_MASK(EV_REP);
 151         input_dev->keycode = data->keycodes;
 152         input_dev->keycodesize = sizeof(data->keycodes[0]);
 153         input_dev->keycodemax = pdata->key_maxval + 1;
 154
 155         for (i = 0; i < pdata->keymap_size; i++) {
 156                 unsigned int val = MCS_KEY_VAL(pdata->keymap[i]);
 157                 unsigned int code = MCS_KEY_CODE(pdata->keymap[i]);
 158
 159                 data->keycodes[val] = code;
 160                 __set_bit(code, input_dev->keybit);
 161         }
 162
 163         input_set_capability(input_dev, EV_MSC, MSC_SCAN);
 164         input_set_drvdata(input_dev, data);
 165
 166         if (pdata->cfg_pin)
 167                 pdata->cfg_pin();
 168
 169         if (pdata->poweron) {
 170                 data->poweron = pdata->poweron;
 171                 data->poweron(true);
 172         }
 173
 174         error = request_threaded_irq(client->irq, NULL, mcs_touchkey_interrupt,
 175                                      IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
 176                                      client->dev.driver->name, data);
 177         if (error) {
 178                 dev_err(&client->dev, "Failed to register interrupt\n");
 179                 goto err_free_mem;
 180         }
 181
 182         error = input_register_device(input_dev);
 183         if (error)
 184                 goto err_free_irq;
 185
 186         i2c_set_clientdata(client, data);
 187         return 0;
 188
 189 err_free_irq:
 190         free_irq(client->irq, data);
 191 err_free_mem:
 192         input_free_device(input_dev);
 193         kfree(data);
 194         return error;
 195 }
 196
 197 static void mcs_touchkey_remove(struct i2c_client *client)
 198 {
 199         struct mcs_touchkey_data *data = i2c_get_clientdata(client);
 200
 201         free_irq(client->irq, data);
 202         if (data->poweron)
 203                 data->poweron(false);
 204         input_unregister_device(data->input_dev);
 205         kfree(data);
 206 }
 207
 208 static void mcs_touchkey_shutdown(struct i2c_client *client)
 209 {
 210         struct mcs_touchkey_data *data = i2c_get_clientdata(client);
 211
 212         if (data->poweron)
 213                 data->poweron(false);
 214 }
 215
 216 static int mcs_touchkey_suspend(struct device *dev)
 217 {
 218         struct mcs_touchkey_data *data = dev_get_drvdata(dev);
 219         struct i2c_client *client = data->client;
 220
 221         /* Disable the work */
 222         disable_irq(client->irq);
 223
 224         /* Finally turn off the power */
 225         if (data->poweron)
 226                 data->poweron(false);
 227
 228         return 0;
 229 }
 230
 231 static int mcs_touchkey_resume(struct device *dev)
 232 {
 233         struct mcs_touchkey_data *data = dev_get_drvdata(dev);
 234         struct i2c_client *client = data->client;
 235
 236         /* Enable the device first */
 237         if (data->poweron)
 238                 data->poweron(true);
 239
 240         /* Enable irq again */
 241         enable_irq(client->irq);
 242
 243         return 0;
 244 }
 245
 246 static DEFINE_SIMPLE_DEV_PM_OPS(mcs_touchkey_pm_ops,
 247                                 mcs_touchkey_suspend, mcs_touchkey_resume);
 248
 249 static const struct i2c_device_id mcs_touchkey_id[] = {
 250         { "mcs5000_touchkey", MCS5000_TOUCHKEY },
 251         { "mcs5080_touchkey", MCS5080_TOUCHKEY },
 252         { }
 253 };
 254 MODULE_DEVICE_TABLE(i2c, mcs_touchkey_id);
 255
 256 static struct i2c_driver mcs_touchkey_driver = {
 257         .driver = {
 258                 .name   = "mcs_touchkey",
 259                 .pm     = pm_sleep_ptr(&mcs_touchkey_pm_ops),
 260         },
 261         .probe_new      = mcs_touchkey_probe,
 262         .remove         = mcs_touchkey_remove,
 263         .shutdown       = mcs_touchkey_shutdown,
 264         .id_table       = mcs_touchkey_id,
 265 };
 266
 267 module_i2c_driver(mcs_touchkey_driver);
 268
 269 /* Module information */
 270 MODULE_AUTHOR("Joonyoung Shim <[email protected]>");
 271 MODULE_AUTHOR("HeungJun Kim <[email protected]>");
 272 MODULE_DESCRIPTION("Touchkey driver for MELFAS MCS5000/5080 controller");
 273 MODULE_LICENSE("GPL");