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 <riverful.kim@samsung.com>
   7  * Author: Joonyoung Shim <jy0922.shim@samsung.com>
   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 void mcs_touchkey_poweroff(void *data)
  96 {
  97         struct mcs_touchkey_data *touchkey = data;
  98
  99         touchkey->poweron(false);
 100 }
 101
 102 static int mcs_touchkey_probe(struct i2c_client *client)
 103 {
 104         const struct i2c_device_id *id = i2c_client_get_device_id(client);
 105         const struct mcs_platform_data *pdata;
 106         struct mcs_touchkey_data *data;
 107         struct input_dev *input_dev;
 108         unsigned int fw_reg;
 109         int fw_ver;
 110         int error;
 111         int i;
 112
 113         pdata = dev_get_platdata(&client->dev);
 114         if (!pdata) {
 115                 dev_err(&client->dev, "no platform data defined\n");
 116                 return -EINVAL;
 117         }
 118
 119         data = devm_kzalloc(&client->dev,
 120                             struct_size(data, keycodes, pdata->key_maxval + 1),
 121                             GFP_KERNEL);
 122         if (!data)
 123                 return -ENOMEM;
 124
 125         input_dev = devm_input_allocate_device(&client->dev);
 126         if (!input_dev) {
 127                 dev_err(&client->dev, "Failed to allocate input device\n");
 128                 return -ENOMEM;
 129         }
 130
 131         data->client = client;
 132         data->input_dev = input_dev;
 133
 134         if (id->driver_data == MCS5000_TOUCHKEY) {
 135                 data->chip.status_reg = MCS5000_TOUCHKEY_STATUS;
 136                 data->chip.pressbit = MCS5000_TOUCHKEY_STATUS_PRESS;
 137                 data->chip.baseval = MCS5000_TOUCHKEY_BASE_VAL;
 138                 fw_reg = MCS5000_TOUCHKEY_FW;
 139         } else {
 140                 data->chip.status_reg = MCS5080_TOUCHKEY_STATUS;
 141                 data->chip.pressbit = MCS5080_TOUCHKEY_STATUS_PRESS;
 142                 data->chip.press_invert = 1;
 143                 data->chip.baseval = MCS5080_TOUCHKEY_BASE_VAL;
 144                 fw_reg = MCS5080_TOUCHKEY_FW;
 145         }
 146
 147         fw_ver = i2c_smbus_read_byte_data(client, fw_reg);
 148         if (fw_ver < 0) {
 149                 dev_err(&client->dev, "i2c read error[%d]\n", fw_ver);
 150                 return fw_ver;
 151         }
 152         dev_info(&client->dev, "Firmware version: %d\n", fw_ver);
 153
 154         input_dev->name = "MELFAS MCS Touchkey";
 155         input_dev->id.bustype = BUS_I2C;
 156         input_dev->evbit[0] = BIT_MASK(EV_KEY);
 157         if (!pdata->no_autorepeat)
 158                 input_dev->evbit[0] |= BIT_MASK(EV_REP);
 159         input_dev->keycode = data->keycodes;
 160         input_dev->keycodesize = sizeof(data->keycodes[0]);
 161         input_dev->keycodemax = pdata->key_maxval + 1;
 162
 163         for (i = 0; i < pdata->keymap_size; i++) {
 164                 unsigned int val = MCS_KEY_VAL(pdata->keymap[i]);
 165                 unsigned int code = MCS_KEY_CODE(pdata->keymap[i]);
 166
 167                 data->keycodes[val] = code;
 168                 __set_bit(code, input_dev->keybit);
 169         }
 170
 171         input_set_capability(input_dev, EV_MSC, MSC_SCAN);
 172         input_set_drvdata(input_dev, data);
 173
 174         if (pdata->cfg_pin)
 175                 pdata->cfg_pin();
 176
 177         if (pdata->poweron) {
 178                 data->poweron = pdata->poweron;
 179                 data->poweron(true);
 180
 181                 error = devm_add_action_or_reset(&client->dev,
 182                                                  mcs_touchkey_poweroff, data);
 183                 if (error)
 184                         return error;
 185         }
 186
 187         error = devm_request_threaded_irq(&client->dev, client->irq,
 188                                           NULL, mcs_touchkey_interrupt,
 189                                           IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
 190                                           client->dev.driver->name, data);
 191         if (error) {
 192                 dev_err(&client->dev, "Failed to register interrupt\n");
 193                 return error;
 194         }
 195
 196         error = input_register_device(input_dev);
 197         if (error)
 198                 return error;
 199
 200         i2c_set_clientdata(client, data);
 201         return 0;
 202 }
 203
 204 static void mcs_touchkey_shutdown(struct i2c_client *client)
 205 {
 206         struct mcs_touchkey_data *data = i2c_get_clientdata(client);
 207
 208         if (data->poweron)
 209                 data->poweron(false);
 210 }
 211
 212 static int mcs_touchkey_suspend(struct device *dev)
 213 {
 214         struct mcs_touchkey_data *data = dev_get_drvdata(dev);
 215         struct i2c_client *client = data->client;
 216
 217         /* Disable the work */
 218         disable_irq(client->irq);
 219
 220         /* Finally turn off the power */
 221         if (data->poweron)
 222                 data->poweron(false);
 223
 224         return 0;
 225 }
 226
 227 static int mcs_touchkey_resume(struct device *dev)
 228 {
 229         struct mcs_touchkey_data *data = dev_get_drvdata(dev);
 230         struct i2c_client *client = data->client;
 231
 232         /* Enable the device first */
 233         if (data->poweron)
 234                 data->poweron(true);
 235
 236         /* Enable irq again */
 237         enable_irq(client->irq);
 238
 239         return 0;
 240 }
 241
 242 static DEFINE_SIMPLE_DEV_PM_OPS(mcs_touchkey_pm_ops,
 243                                 mcs_touchkey_suspend, mcs_touchkey_resume);
 244
 245 static const struct i2c_device_id mcs_touchkey_id[] = {
 246         { "mcs5000_touchkey", MCS5000_TOUCHKEY },
 247         { "mcs5080_touchkey", MCS5080_TOUCHKEY },
 248         { }
 249 };
 250 MODULE_DEVICE_TABLE(i2c, mcs_touchkey_id);
 251
 252 static struct i2c_driver mcs_touchkey_driver = {
 253         .driver = {
 254                 .name   = "mcs_touchkey",
 255                 .pm     = pm_sleep_ptr(&mcs_touchkey_pm_ops),
 256         },
 257         .probe          = mcs_touchkey_probe,
 258         .shutdown       = mcs_touchkey_shutdown,
 259         .id_table       = mcs_touchkey_id,
 260 };
 261
 262 module_i2c_driver(mcs_touchkey_driver);
 263
 264 /* Module information */
 265 MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>");
 266 MODULE_AUTHOR("HeungJun Kim <riverful.kim@samsung.com>");
 267 MODULE_DESCRIPTION("Touchkey driver for MELFAS MCS5000/5080 controller");
 268 MODULE_LICENSE("GPL");