drivers/input/joystick/as5011.c

   1 /*
   2  * Copyright (c) 2010, 2011 Fabien Marteau <fabien.marteau@armadeus.com>
   3  * Sponsored by ARMadeus Systems
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  18  *
  19  * Driver for Austria Microsystems joysticks AS5011
  20  *
  21  * TODO:
  22  *      - Power on the chip when open() and power down when close()
  23  *      - Manage power mode
  24  */
  25
  26 #include <linux/i2c.h>
  27 #include <linux/interrupt.h>
  28 #include <linux/input.h>
  29 #include <linux/gpio.h>
  30 #include <linux/delay.h>
  31 #include <linux/input/as5011.h>
  32 #include <linux/slab.h>
  33 #include <linux/module.h>
  34
  35 #define DRIVER_DESC "Driver for Austria Microsystems AS5011 joystick"
  36 #define MODULE_DEVICE_ALIAS "as5011"
  37
  38 MODULE_AUTHOR("Fabien Marteau <fabien.marteau@armadeus.com>");
  39 MODULE_DESCRIPTION(DRIVER_DESC);
  40 MODULE_LICENSE("GPL");
  41
  42 /* registers */
  43 #define AS5011_CTRL1            0x76
  44 #define AS5011_CTRL2            0x75
  45 #define AS5011_XP               0x43
  46 #define AS5011_XN               0x44
  47 #define AS5011_YP               0x53
  48 #define AS5011_YN               0x54
  49 #define AS5011_X_REG            0x41
  50 #define AS5011_Y_REG            0x42
  51 #define AS5011_X_RES_INT        0x51
  52 #define AS5011_Y_RES_INT        0x52
  53
  54 /* CTRL1 bits */
  55 #define AS5011_CTRL1_LP_PULSED          0x80
  56 #define AS5011_CTRL1_LP_ACTIVE          0x40
  57 #define AS5011_CTRL1_LP_CONTINUE        0x20
  58 #define AS5011_CTRL1_INT_WUP_EN         0x10
  59 #define AS5011_CTRL1_INT_ACT_EN         0x08
  60 #define AS5011_CTRL1_EXT_CLK_EN         0x04
  61 #define AS5011_CTRL1_SOFT_RST           0x02
  62 #define AS5011_CTRL1_DATA_VALID         0x01
  63
  64 /* CTRL2 bits */
  65 #define AS5011_CTRL2_EXT_SAMPLE_EN      0x08
  66 #define AS5011_CTRL2_RC_BIAS_ON         0x04
  67 #define AS5011_CTRL2_INV_SPINNING       0x02
  68
  69 #define AS5011_MAX_AXIS 80
  70 #define AS5011_MIN_AXIS (-80)
  71 #define AS5011_FUZZ     8
  72 #define AS5011_FLAT     40
  73
  74 struct as5011_device {
  75         struct input_dev *input_dev;
  76         struct i2c_client *i2c_client;
  77         unsigned int button_gpio;
  78         unsigned int button_irq;
  79         unsigned int axis_irq;
  80 };
  81
  82 static int as5011_i2c_write(struct i2c_client *client,
  83                             uint8_t aregaddr,
  84                             uint8_t avalue)
  85 {
  86         uint8_t data[2] = { aregaddr, avalue };
  87         struct i2c_msg msg = {
  88                 .addr = client->addr,
  89                 .flags = I2C_M_IGNORE_NAK,
  90                 .len = 2,
  91                 .buf = (uint8_t *)data
  92         };
  93         int error;
  94
  95         error = i2c_transfer(client->adapter, &msg, 1);
  96         return error < 0 ? error : 0;
  97 }
  98
  99 static int as5011_i2c_read(struct i2c_client *client,
 100                            uint8_t aregaddr, signed char *value)
 101 {
 102         uint8_t data[2] = { aregaddr };
 103         struct i2c_msg msg_set[2] = {
 104                 {
 105                         .addr = client->addr,
 106                         .flags = I2C_M_REV_DIR_ADDR,
 107                         .len = 1,
 108                         .buf = (uint8_t *)data
 109                 },
 110                 {
 111                         .addr = client->addr,
 112                         .flags = I2C_M_RD | I2C_M_NOSTART,
 113                         .len = 1,
 114                         .buf = (uint8_t *)data
 115                 }
 116         };
 117         int error;
 118
 119         error = i2c_transfer(client->adapter, msg_set, 2);
 120         if (error < 0)
 121                 return error;
 122
 123         *value = data[0] & 0x80 ? -1 * (1 + ~data[0]) : data[0];
 124         return 0;
 125 }
 126
 127 static irqreturn_t as5011_button_interrupt(int irq, void *dev_id)
 128 {
 129         struct as5011_device *as5011 = dev_id;
 130         int val = gpio_get_value_cansleep(as5011->button_gpio);
 131
 132         input_report_key(as5011->input_dev, BTN_JOYSTICK, !val);
 133         input_sync(as5011->input_dev);
 134
 135         return IRQ_HANDLED;
 136 }
 137
 138 static irqreturn_t as5011_axis_interrupt(int irq, void *dev_id)
 139 {
 140         struct as5011_device *as5011 = dev_id;
 141         int error;
 142         signed char x, y;
 143
 144         error = as5011_i2c_read(as5011->i2c_client, AS5011_X_RES_INT, &x);
 145         if (error < 0)
 146                 goto out;
 147
 148         error = as5011_i2c_read(as5011->i2c_client, AS5011_Y_RES_INT, &y);
 149         if (error < 0)
 150                 goto out;
 151
 152         input_report_abs(as5011->input_dev, ABS_X, x);
 153         input_report_abs(as5011->input_dev, ABS_Y, y);
 154         input_sync(as5011->input_dev);
 155
 156 out:
 157         return IRQ_HANDLED;
 158 }
 159
 160 static int as5011_configure_chip(struct as5011_device *as5011,
 161                                 const struct as5011_platform_data *plat_dat)
 162 {
 163         struct i2c_client *client = as5011->i2c_client;
 164         int error;
 165         signed char value;
 166
 167         /* chip soft reset */
 168         error = as5011_i2c_write(client, AS5011_CTRL1,
 169                                  AS5011_CTRL1_SOFT_RST);
 170         if (error < 0) {
 171                 dev_err(&client->dev, "Soft reset failed\n");
 172                 return error;
 173         }
 174
 175         mdelay(10);
 176
 177         error = as5011_i2c_write(client, AS5011_CTRL1,
 178                                  AS5011_CTRL1_LP_PULSED |
 179                                  AS5011_CTRL1_LP_ACTIVE |
 180                                  AS5011_CTRL1_INT_ACT_EN);
 181         if (error < 0) {
 182                 dev_err(&client->dev, "Power config failed\n");
 183                 return error;
 184         }
 185
 186         error = as5011_i2c_write(client, AS5011_CTRL2,
 187                                  AS5011_CTRL2_INV_SPINNING);
 188         if (error < 0) {
 189                 dev_err(&client->dev, "Can't invert spinning\n");
 190                 return error;
 191         }
 192
 193         /* write threshold */
 194         error = as5011_i2c_write(client, AS5011_XP, plat_dat->xp);
 195         if (error < 0) {
 196                 dev_err(&client->dev, "Can't write threshold\n");
 197                 return error;
 198         }
 199
 200         error = as5011_i2c_write(client, AS5011_XN, plat_dat->xn);
 201         if (error < 0) {
 202                 dev_err(&client->dev, "Can't write threshold\n");
 203                 return error;
 204         }
 205
 206         error = as5011_i2c_write(client, AS5011_YP, plat_dat->yp);
 207         if (error < 0) {
 208                 dev_err(&client->dev, "Can't write threshold\n");
 209                 return error;
 210         }
 211
 212         error = as5011_i2c_write(client, AS5011_YN, plat_dat->yn);
 213         if (error < 0) {
 214                 dev_err(&client->dev, "Can't write threshold\n");
 215                 return error;
 216         }
 217
 218         /* to free irq gpio in chip */
 219         error = as5011_i2c_read(client, AS5011_X_RES_INT, &value);
 220         if (error < 0) {
 221                 dev_err(&client->dev, "Can't read i2c X resolution value\n");
 222                 return error;
 223         }
 224
 225         return 0;
 226 }
 227
 228 static int as5011_probe(struct i2c_client *client,
 229                          const struct i2c_device_id *id)
 230 {
 231         const struct as5011_platform_data *plat_data;
 232         struct as5011_device *as5011;
 233         struct input_dev *input_dev;
 234         int irq;
 235         int error;
 236
 237         plat_data = dev_get_platdata(&client->dev);
 238         if (!plat_data)
 239                 return -EINVAL;
 240
 241         if (!plat_data->axis_irq) {
 242                 dev_err(&client->dev, "No axis IRQ?\n");
 243                 return -EINVAL;
 244         }
 245
 246         if (!i2c_check_functionality(client->adapter,
 247                                      I2C_FUNC_NOSTART |
 248                                      I2C_FUNC_PROTOCOL_MANGLING)) {
 249                 dev_err(&client->dev,
 250                         "need i2c bus that supports protocol mangling\n");
 251                 return -ENODEV;
 252         }
 253
 254         as5011 = kmalloc(sizeof(struct as5011_device), GFP_KERNEL);
 255         input_dev = input_allocate_device();
 256         if (!as5011 || !input_dev) {
 257                 dev_err(&client->dev,
 258                         "Can't allocate memory for device structure\n");
 259                 error = -ENOMEM;
 260                 goto err_free_mem;
 261         }
 262
 263         as5011->i2c_client = client;
 264         as5011->input_dev = input_dev;
 265         as5011->button_gpio = plat_data->button_gpio;
 266         as5011->axis_irq = plat_data->axis_irq;
 267
 268         input_dev->name = "Austria Microsystem as5011 joystick";
 269         input_dev->id.bustype = BUS_I2C;
 270         input_dev->dev.parent = &client->dev;
 271
 272         input_set_capability(input_dev, EV_KEY, BTN_JOYSTICK);
 273
 274         input_set_abs_params(input_dev, ABS_X,
 275                 AS5011_MIN_AXIS, AS5011_MAX_AXIS, AS5011_FUZZ, AS5011_FLAT);
 276         input_set_abs_params(as5011->input_dev, ABS_Y,
 277                 AS5011_MIN_AXIS, AS5011_MAX_AXIS, AS5011_FUZZ, AS5011_FLAT);
 278
 279         error = gpio_request(as5011->button_gpio, "AS5011 button");
 280         if (error < 0) {
 281                 dev_err(&client->dev, "Failed to request button gpio\n");
 282                 goto err_free_mem;
 283         }
 284
 285         irq = gpio_to_irq(as5011->button_gpio);
 286         if (irq < 0) {
 287                 dev_err(&client->dev,
 288                         "Failed to get irq number for button gpio\n");
 289                 error = irq;
 290                 goto err_free_button_gpio;
 291         }
 292
 293         as5011->button_irq = irq;
 294
 295         error = request_threaded_irq(as5011->button_irq,
 296                                      NULL, as5011_button_interrupt,
 297                                      IRQF_TRIGGER_RISING |
 298                                         IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
 299                                      "as5011_button", as5011);
 300         if (error < 0) {
 301                 dev_err(&client->dev,
 302                         "Can't allocate button irq %d\n", as5011->button_irq);
 303                 goto err_free_button_gpio;
 304         }
 305
 306         error = as5011_configure_chip(as5011, plat_data);
 307         if (error)
 308                 goto err_free_button_irq;
 309
 310         error = request_threaded_irq(as5011->axis_irq, NULL,
 311                                      as5011_axis_interrupt,
 312                                      plat_data->axis_irqflags | IRQF_ONESHOT,
 313                                      "as5011_joystick", as5011);
 314         if (error) {
 315                 dev_err(&client->dev,
 316                         "Can't allocate axis irq %d\n", plat_data->axis_irq);
 317                 goto err_free_button_irq;
 318         }
 319
 320         error = input_register_device(as5011->input_dev);
 321         if (error) {
 322                 dev_err(&client->dev, "Failed to register input device\n");
 323                 goto err_free_axis_irq;
 324         }
 325
 326         i2c_set_clientdata(client, as5011);
 327
 328         return 0;
 329
 330 err_free_axis_irq:
 331         free_irq(as5011->axis_irq, as5011);
 332 err_free_button_irq:
 333         free_irq(as5011->button_irq, as5011);
 334 err_free_button_gpio:
 335         gpio_free(as5011->button_gpio);
 336 err_free_mem:
 337         input_free_device(input_dev);
 338         kfree(as5011);
 339
 340         return error;
 341 }
 342
 343 static int as5011_remove(struct i2c_client *client)
 344 {
 345         struct as5011_device *as5011 = i2c_get_clientdata(client);
 346
 347         free_irq(as5011->axis_irq, as5011);
 348         free_irq(as5011->button_irq, as5011);
 349         gpio_free(as5011->button_gpio);
 350
 351         input_unregister_device(as5011->input_dev);
 352         kfree(as5011);
 353
 354         return 0;
 355 }
 356
 357 static const struct i2c_device_id as5011_id[] = {
 358         { MODULE_DEVICE_ALIAS, 0 },
 359         { }
 360 };
 361 MODULE_DEVICE_TABLE(i2c, as5011_id);
 362
 363 static struct i2c_driver as5011_driver = {
 364         .driver = {
 365                 .name = "as5011",
 366         },
 367         .probe          = as5011_probe,
 368         .remove         = as5011_remove,
 369         .id_table       = as5011_id,
 370 };
 371
 372 module_i2c_driver(as5011_driver);