drivers/input/touchscreen/sx8654.c

   1 /*
   2  * Driver for Semtech SX8654 I2C touchscreen controller.
   3  *
   4  * Copyright (c) 2015 Armadeus Systems
   5  *      Sébastien Szymanski <sebastien.szymanski@armadeus.com>
   6  *
   7  * Using code from:
   8  *  - sx865x.c
   9  *      Copyright (c) 2013 U-MoBo Srl
  10  *      Pierluigi Passaro <p.passaro@u-mobo.com>
  11  *  - sx8650.c
  12  *      Copyright (c) 2009 Wayne Roberts
  13  *  - tsc2007.c
  14  *      Copyright (c) 2008 Kwangwoo Lee
  15  *  - ads7846.c
  16  *      Copyright (c) 2005 David Brownell
  17  *      Copyright (c) 2006 Nokia Corporation
  18  *  - corgi_ts.c
  19  *      Copyright (C) 2004-2005 Richard Purdie
  20  *  - omap_ts.[hc], ads7846.h, ts_osk.c
  21  *      Copyright (C) 2002 MontaVista Software
  22  *      Copyright (C) 2004 Texas Instruments
  23  *      Copyright (C) 2005 Dirk Behme
  24  *
  25  *  This program is free software; you can redistribute it and/or modify
  26  *  it under the terms of the GNU General Public License version 2 as
  27  *  published by the Free Software Foundation.
  28  */
  29
  30 #include <linux/input.h>
  31 #include <linux/module.h>
  32 #include <linux/of.h>
  33 #include <linux/i2c.h>
  34 #include <linux/interrupt.h>
  35 #include <linux/irq.h>
  36
  37 /* register addresses */
  38 #define I2C_REG_TOUCH0                  0x00
  39 #define I2C_REG_TOUCH1                  0x01
  40 #define I2C_REG_CHANMASK                0x04
  41 #define I2C_REG_IRQMASK                 0x22
  42 #define I2C_REG_IRQSRC                  0x23
  43 #define I2C_REG_SOFTRESET               0x3f
  44
  45 /* commands */
  46 #define CMD_READ_REGISTER               0x40
  47 #define CMD_MANUAL                      0xc0
  48 #define CMD_PENTRG                      0xe0
  49
  50 /* value for I2C_REG_SOFTRESET */
  51 #define SOFTRESET_VALUE                 0xde
  52
  53 /* bits for I2C_REG_IRQSRC */
  54 #define IRQ_PENTOUCH_TOUCHCONVDONE      0x08
  55 #define IRQ_PENRELEASE                  0x04
  56
  57 /* bits for RegTouch1 */
  58 #define CONDIRQ                         0x20
  59 #define FILT_7SA                        0x03
  60
  61 /* bits for I2C_REG_CHANMASK */
  62 #define CONV_X                          0x80
  63 #define CONV_Y                          0x40
  64
  65 /* coordinates rate: higher nibble of CTRL0 register */
  66 #define RATE_MANUAL                     0x00
  67 #define RATE_5000CPS                    0xf0
  68
  69 /* power delay: lower nibble of CTRL0 register */
  70 #define POWDLY_1_1MS                    0x0b
  71
  72 #define MAX_12BIT                       ((1 << 12) - 1)
  73
  74 struct sx8654 {
  75         struct input_dev *input;
  76         struct i2c_client *client;
  77 };
  78
  79 static irqreturn_t sx8654_irq(int irq, void *handle)
  80 {
  81         struct sx8654 *sx8654 = handle;
  82         int irqsrc;
  83         u8 data[4];
  84         unsigned int x, y;
  85         int retval;
  86
  87         irqsrc = i2c_smbus_read_byte_data(sx8654->client,
  88                                           CMD_READ_REGISTER | I2C_REG_IRQSRC);
  89         dev_dbg(&sx8654->client->dev, "irqsrc = 0x%x", irqsrc);
  90
  91         if (irqsrc < 0)
  92                 goto out;
  93
  94         if (irqsrc & IRQ_PENRELEASE) {
  95                 dev_dbg(&sx8654->client->dev, "pen release interrupt");
  96
  97                 input_report_key(sx8654->input, BTN_TOUCH, 0);
  98                 input_sync(sx8654->input);
  99         }
 100
 101         if (irqsrc & IRQ_PENTOUCH_TOUCHCONVDONE) {
 102                 dev_dbg(&sx8654->client->dev, "pen touch interrupt");
 103
 104                 retval = i2c_master_recv(sx8654->client, data, sizeof(data));
 105                 if (retval != sizeof(data))
 106                         goto out;
 107
 108                 /* invalid data */
 109                 if (unlikely(data[0] & 0x80 || data[2] & 0x80))
 110                         goto out;
 111
 112                 x = ((data[0] & 0xf) << 8) | (data[1]);
 113                 y = ((data[2] & 0xf) << 8) | (data[3]);
 114
 115                 input_report_abs(sx8654->input, ABS_X, x);
 116                 input_report_abs(sx8654->input, ABS_Y, y);
 117                 input_report_key(sx8654->input, BTN_TOUCH, 1);
 118                 input_sync(sx8654->input);
 119
 120                 dev_dbg(&sx8654->client->dev, "point(%4d,%4d)\n", x, y);
 121         }
 122
 123 out:
 124         return IRQ_HANDLED;
 125 }
 126
 127 static int sx8654_open(struct input_dev *dev)
 128 {
 129         struct sx8654 *sx8654 = input_get_drvdata(dev);
 130         struct i2c_client *client = sx8654->client;
 131         int error;
 132
 133         /* enable pen trigger mode */
 134         error = i2c_smbus_write_byte_data(client, I2C_REG_TOUCH0,
 135                                           RATE_5000CPS | POWDLY_1_1MS);
 136         if (error) {
 137                 dev_err(&client->dev, "writing to I2C_REG_TOUCH0 failed");
 138                 return error;
 139         }
 140
 141         error = i2c_smbus_write_byte(client, CMD_PENTRG);
 142         if (error) {
 143                 dev_err(&client->dev, "writing command CMD_PENTRG failed");
 144                 return error;
 145         }
 146
 147         enable_irq(client->irq);
 148
 149         return 0;
 150 }
 151
 152 static void sx8654_close(struct input_dev *dev)
 153 {
 154         struct sx8654 *sx8654 = input_get_drvdata(dev);
 155         struct i2c_client *client = sx8654->client;
 156         int error;
 157
 158         disable_irq(client->irq);
 159
 160         /* enable manual mode mode */
 161         error = i2c_smbus_write_byte(client, CMD_MANUAL);
 162         if (error) {
 163                 dev_err(&client->dev, "writing command CMD_MANUAL failed");
 164                 return;
 165         }
 166
 167         error = i2c_smbus_write_byte_data(client, I2C_REG_TOUCH0, 0);
 168         if (error) {
 169                 dev_err(&client->dev, "writing to I2C_REG_TOUCH0 failed");
 170                 return;
 171         }
 172 }
 173
 174 static int sx8654_probe(struct i2c_client *client,
 175                         const struct i2c_device_id *id)
 176 {
 177         struct sx8654 *sx8654;
 178         struct input_dev *input;
 179         int error;
 180
 181         if (!i2c_check_functionality(client->adapter,
 182                                      I2C_FUNC_SMBUS_READ_WORD_DATA))
 183                 return -ENXIO;
 184
 185         sx8654 = devm_kzalloc(&client->dev, sizeof(*sx8654), GFP_KERNEL);
 186         if (!sx8654)
 187                 return -ENOMEM;
 188
 189         input = devm_input_allocate_device(&client->dev);
 190         if (!input)
 191                 return -ENOMEM;
 192
 193         input->name = "SX8654 I2C Touchscreen";
 194         input->id.bustype = BUS_I2C;
 195         input->dev.parent = &client->dev;
 196         input->open = sx8654_open;
 197         input->close = sx8654_close;
 198
 199         __set_bit(INPUT_PROP_DIRECT, input->propbit);
 200         input_set_capability(input, EV_KEY, BTN_TOUCH);
 201         input_set_abs_params(input, ABS_X, 0, MAX_12BIT, 0, 0);
 202         input_set_abs_params(input, ABS_Y, 0, MAX_12BIT, 0, 0);
 203
 204         sx8654->client = client;
 205         sx8654->input = input;
 206
 207         input_set_drvdata(sx8654->input, sx8654);
 208
 209         error = i2c_smbus_write_byte_data(client, I2C_REG_SOFTRESET,
 210                                           SOFTRESET_VALUE);
 211         if (error) {
 212                 dev_err(&client->dev, "writing softreset value failed");
 213                 return error;
 214         }
 215
 216         error = i2c_smbus_write_byte_data(client, I2C_REG_CHANMASK,
 217                                           CONV_X | CONV_Y);
 218         if (error) {
 219                 dev_err(&client->dev, "writing to I2C_REG_CHANMASK failed");
 220                 return error;
 221         }
 222
 223         error = i2c_smbus_write_byte_data(client, I2C_REG_IRQMASK,
 224                                           IRQ_PENTOUCH_TOUCHCONVDONE |
 225                                                 IRQ_PENRELEASE);
 226         if (error) {
 227                 dev_err(&client->dev, "writing to I2C_REG_IRQMASK failed");
 228                 return error;
 229         }
 230
 231         error = i2c_smbus_write_byte_data(client, I2C_REG_TOUCH1,
 232                                           CONDIRQ | FILT_7SA);
 233         if (error) {
 234                 dev_err(&client->dev, "writing to I2C_REG_TOUCH1 failed");
 235                 return error;
 236         }
 237
 238         error = devm_request_threaded_irq(&client->dev, client->irq,
 239                                           NULL, sx8654_irq,
 240                                           IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
 241                                           client->name, sx8654);
 242         if (error) {
 243                 dev_err(&client->dev,
 244                         "Failed to enable IRQ %d, error: %d\n",
 245                         client->irq, error);
 246                 return error;
 247         }
 248
 249         /* Disable the IRQ, we'll enable it in sx8654_open() */
 250         disable_irq(client->irq);
 251
 252         error = input_register_device(sx8654->input);
 253         if (error)
 254                 return error;
 255
 256         return 0;
 257 }
 258
 259 #ifdef CONFIG_OF
 260 static const struct of_device_id sx8654_of_match[] = {
 261         { .compatible = "semtech,sx8654", },
 262         { },
 263 };
 264 MODULE_DEVICE_TABLE(of, sx8654_of_match);
 265 #endif
 266
 267 static const struct i2c_device_id sx8654_id_table[] = {
 268         { "semtech_sx8654", 0 },
 269         { },
 270 };
 271 MODULE_DEVICE_TABLE(i2c, sx8654_id_table);
 272
 273 static struct i2c_driver sx8654_driver = {
 274         .driver = {
 275                 .name = "sx8654",
 276                 .of_match_table = of_match_ptr(sx8654_of_match),
 277         },
 278         .id_table = sx8654_id_table,
 279         .probe = sx8654_probe,
 280 };
 281 module_i2c_driver(sx8654_driver);
 282
 283 MODULE_AUTHOR("Sébastien Szymanski <sebastien.szymanski@armadeus.com>");
 284 MODULE_DESCRIPTION("Semtech SX8654 I2C Touchscreen Driver");
 285 MODULE_LICENSE("GPL");