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
  34 #define DRIVER_DESC "Driver for Austria Microsystems AS5011 joystick"
  35 #define MODULE_DEVICE_ALIAS "as5011"
  36
  37 MODULE_AUTHOR("Fabien Marteau <fabien.marteau@armadeus.com>");
  38 MODULE_DESCRIPTION(DRIVER_DESC);
  39 MODULE_LICENSE("GPL");
  40
  41 /* registers */
  42 #define AS5011_CTRL1            0x76
  43 #define AS5011_CTRL2            0x75
  44 #define AS5011_XP               0x43
  45 #define AS5011_XN               0x44
  46 #define AS5011_YP               0x53
  47 #define AS5011_YN               0x54
  48 #define AS5011_X_REG            0x41
  49 #define AS5011_Y_REG            0x42
  50 #define AS5011_X_RES_INT        0x51
  51 #define AS5011_Y_RES_INT        0x52
  52
  53 /* CTRL1 bits */
  54 #define AS5011_CTRL1_LP_PULSED          0x80
  55 #define AS5011_CTRL1_LP_ACTIVE          0x40
  56 #define AS5011_CTRL1_LP_CONTINUE        0x20
  57 #define AS5011_CTRL1_INT_WUP_EN         0x10
  58 #define AS5011_CTRL1_INT_ACT_EN         0x08
  59 #define AS5011_CTRL1_EXT_CLK_EN         0x04
  60 #define AS5011_CTRL1_SOFT_RST           0x02
  61 #define AS5011_CTRL1_DATA_VALID         0x01
  62
  63 /* CTRL2 bits */
  64 #define AS5011_CTRL2_EXT_SAMPLE_EN      0x08
  65 #define AS5011_CTRL2_RC_BIAS_ON         0x04
  66 #define AS5011_CTRL2_INV_SPINNING       0x02
  67
  68 #define AS5011_MAX_AXIS 80
  69 #define AS5011_MIN_AXIS (-80)
  70 #define AS5011_FUZZ     8
  71 #define AS5011_FLAT     40
  72
  73 struct as5011_device {
  74         struct input_dev *input_dev;
  75         struct i2c_client *i2c_client;
  76         unsigned int button_gpio;
  77         unsigned int button_irq;
  78         unsigned int axis_irq;
  79 };
  80
  81 static int as5011_i2c_write(struct i2c_client *client,
  82                             uint8_t aregaddr,
  83                             uint8_t avalue)
  84 {
  85         uint8_t data[2] = { aregaddr, avalue };
  86         struct i2c_msg msg = {
  87                 client->addr, I2C_M_IGNORE_NAK, 2, (uint8_t *)data
  88         };
  89         int error;
  90
  91         error = i2c_transfer(client->adapter, &msg, 1);
  92         return error < 0 ? error : 0;
  93 }
  94
  95 static int as5011_i2c_read(struct i2c_client *client,
  96                            uint8_t aregaddr, signed char *value)
  97 {
  98         uint8_t data[2] = { aregaddr };
  99         struct i2c_msg msg_set[2] = {
 100                 { client->addr, I2C_M_REV_DIR_ADDR, 1, (uint8_t *)data },
 101                 { client->addr, I2C_M_RD | I2C_M_NOSTART, 1, (uint8_t *)data }
 102         };
 103         int error;
 104
 105         error = i2c_transfer(client->adapter, msg_set, 2);
 106         if (error < 0)
 107                 return error;
 108
 109         *value = data[0] & 0x80 ? -1 * (1 + ~data[0]) : data[0];
 110         return 0;
 111 }
 112
 113 static irqreturn_t as5011_button_interrupt(int irq, void *dev_id)
 114 {
 115         struct as5011_device *as5011 = dev_id;
 116         int val = gpio_get_value_cansleep(as5011->button_gpio);
 117
 118         input_report_key(as5011->input_dev, BTN_JOYSTICK, !val);
 119         input_sync(as5011->input_dev);
 120
 121         return IRQ_HANDLED;
 122 }
 123
 124 static irqreturn_t as5011_axis_interrupt(int irq, void *dev_id)
 125 {
 126         struct as5011_device *as5011 = dev_id;
 127         int error;
 128         signed char x, y;
 129
 130         error = as5011_i2c_read(as5011->i2c_client, AS5011_X_RES_INT, &x);
 131         if (error < 0)
 132                 goto out;
 133
 134         error = as5011_i2c_read(as5011->i2c_client, AS5011_Y_RES_INT, &y);
 135         if (error < 0)
 136                 goto out;
 137
 138         input_report_abs(as5011->input_dev, ABS_X, x);
 139         input_report_abs(as5011->input_dev, ABS_Y, y);
 140         input_sync(as5011->input_dev);
 141
 142 out:
 143         return IRQ_HANDLED;
 144 }
 145
 146 static int __devinit as5011_configure_chip(struct as5011_device *as5011,
 147                                 const struct as5011_platform_data *plat_dat)
 148 {
 149         struct i2c_client *client = as5011->i2c_client;
 150         int error;
 151         signed char value;
 152
 153         /* chip soft reset */
 154         error = as5011_i2c_write(client, AS5011_CTRL1,
 155                                  AS5011_CTRL1_SOFT_RST);
 156         if (error < 0) {
 157                 dev_err(&client->dev, "Soft reset failed\n");
 158                 return error;
 159         }
 160
 161         mdelay(10);
 162
 163         error = as5011_i2c_write(client, AS5011_CTRL1,
 164                                  AS5011_CTRL1_LP_PULSED |
 165                                  AS5011_CTRL1_LP_ACTIVE |
 166                                  AS5011_CTRL1_INT_ACT_EN);
 167         if (error < 0) {
 168                 dev_err(&client->dev, "Power config failed\n");
 169                 return error;
 170         }
 171
 172         error = as5011_i2c_write(client, AS5011_CTRL2,
 173                                  AS5011_CTRL2_INV_SPINNING);
 174         if (error < 0) {
 175                 dev_err(&client->dev, "Can't invert spinning\n");
 176                 return error;
 177         }
 178
 179         /* write threshold */
 180         error = as5011_i2c_write(client, AS5011_XP, plat_dat->xp);
 181         if (error < 0) {
 182                 dev_err(&client->dev, "Can't write threshold\n");
 183                 return error;
 184         }
 185
 186         error = as5011_i2c_write(client, AS5011_XN, plat_dat->xn);
 187         if (error < 0) {
 188                 dev_err(&client->dev, "Can't write threshold\n");
 189                 return error;
 190         }
 191
 192         error = as5011_i2c_write(client, AS5011_YP, plat_dat->yp);
 193         if (error < 0) {
 194                 dev_err(&client->dev, "Can't write threshold\n");
 195                 return error;
 196         }
 197
 198         error = as5011_i2c_write(client, AS5011_YN, plat_dat->yn);
 199         if (error < 0) {
 200                 dev_err(&client->dev, "Can't write threshold\n");
 201                 return error;
 202         }
 203
 204         /* to free irq gpio in chip */
 205         error = as5011_i2c_read(client, AS5011_X_RES_INT, &value);
 206         if (error < 0) {
 207                 dev_err(&client->dev, "Can't read i2c X resolution value\n");
 208                 return error;
 209         }
 210
 211         return 0;
 212 }
 213
 214 static int __devinit as5011_probe(struct i2c_client *client,
 215                                 const struct i2c_device_id *id)
 216 {
 217         const struct as5011_platform_data *plat_data;
 218         struct as5011_device *as5011;
 219         struct input_dev *input_dev;
 220         int irq;
 221         int error;
 222
 223         plat_data = client->dev.platform_data;
 224         if (!plat_data)
 225                 return -EINVAL;
 226
 227         if (!plat_data->axis_irq) {
 228                 dev_err(&client->dev, "No axis IRQ?\n");
 229                 return -EINVAL;
 230         }
 231
 232         if (!i2c_check_functionality(client->adapter,
 233                                      I2C_FUNC_PROTOCOL_MANGLING)) {
 234                 dev_err(&client->dev,
 235                         "need i2c bus that supports protocol mangling\n");
 236                 return -ENODEV;
 237         }
 238
 239         as5011 = kmalloc(sizeof(struct as5011_device), GFP_KERNEL);
 240         input_dev = input_allocate_device();
 241         if (!as5011 || !input_dev) {
 242                 dev_err(&client->dev,
 243                         "Can't allocate memory for device structure\n");
 244                 error = -ENOMEM;
 245                 goto err_free_mem;
 246         }
 247
 248         as5011->i2c_client = client;
 249         as5011->input_dev = input_dev;
 250         as5011->button_gpio = plat_data->button_gpio;
 251         as5011->axis_irq = plat_data->axis_irq;
 252
 253         input_dev->name = "Austria Microsystem as5011 joystick";
 254         input_dev->id.bustype = BUS_I2C;
 255         input_dev->dev.parent = &client->dev;
 256
 257         __set_bit(EV_KEY, input_dev->evbit);
 258         __set_bit(EV_ABS, input_dev->evbit);
 259         __set_bit(BTN_JOYSTICK, input_dev->keybit);
 260
 261         input_set_abs_params(input_dev, ABS_X,
 262                 AS5011_MIN_AXIS, AS5011_MAX_AXIS, AS5011_FUZZ, AS5011_FLAT);
 263         input_set_abs_params(as5011->input_dev, ABS_Y,
 264                 AS5011_MIN_AXIS, AS5011_MAX_AXIS, AS5011_FUZZ, AS5011_FLAT);
 265
 266         error = gpio_request(as5011->button_gpio, "AS5011 button");
 267         if (error < 0) {
 268                 dev_err(&client->dev, "Failed to request button gpio\n");
 269                 goto err_free_mem;
 270         }
 271
 272         irq = gpio_to_irq(as5011->button_gpio);
 273         if (irq < 0) {
 274                 dev_err(&client->dev,
 275                         "Failed to get irq number for button gpio\n");
 276                 goto err_free_button_gpio;
 277         }
 278
 279         as5011->button_irq = irq;
 280
 281         error = request_threaded_irq(as5011->button_irq,
 282                                      NULL, as5011_button_interrupt,
 283                                      IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
 284                                      "as5011_button", as5011);
 285         if (error < 0) {
 286                 dev_err(&client->dev,
 287                         "Can't allocate button irq %d\n", as5011->button_irq);
 288                 goto err_free_button_gpio;
 289         }
 290
 291         error = as5011_configure_chip(as5011, plat_data);
 292         if (error)
 293                 goto err_free_button_irq;
 294
 295         error = request_threaded_irq(as5011->axis_irq, NULL,
 296                                      as5011_axis_interrupt,
 297                                      plat_data->axis_irqflags,
 298                                      "as5011_joystick", as5011);
 299         if (error) {
 300                 dev_err(&client->dev,
 301                         "Can't allocate axis irq %d\n", plat_data->axis_irq);
 302                 goto err_free_button_irq;
 303         }
 304
 305         error = input_register_device(as5011->input_dev);
 306         if (error) {
 307                 dev_err(&client->dev, "Failed to register input device\n");
 308                 goto err_free_axis_irq;
 309         }
 310
 311         i2c_set_clientdata(client, as5011);
 312
 313         return 0;
 314
 315 err_free_axis_irq:
 316         free_irq(as5011->axis_irq, as5011);
 317 err_free_button_irq:
 318         free_irq(as5011->button_irq, as5011);
 319 err_free_button_gpio:
 320         gpio_free(as5011->button_gpio);
 321 err_free_mem:
 322         input_free_device(input_dev);
 323         kfree(as5011);
 324
 325         return error;
 326 }
 327
 328 static int __devexit as5011_remove(struct i2c_client *client)
 329 {
 330         struct as5011_device *as5011 = i2c_get_clientdata(client);
 331
 332         free_irq(as5011->axis_irq, as5011);
 333         free_irq(as5011->button_irq, as5011);
 334         gpio_free(as5011->button_gpio);
 335
 336         input_unregister_device(as5011->input_dev);
 337         kfree(as5011);
 338
 339         return 0;
 340 }
 341
 342 static const struct i2c_device_id as5011_id[] = {
 343         { MODULE_DEVICE_ALIAS, 0 },
 344         { }
 345 };
 346 MODULE_DEVICE_TABLE(i2c, as5011_id);
 347
 348 static struct i2c_driver as5011_driver = {
 349         .driver = {
 350                 .name = "as5011",
 351         },
 352         .probe          = as5011_probe,
 353         .remove         = __devexit_p(as5011_remove),
 354         .id_table       = as5011_id,
 355 };
 356
 357 static int __init as5011_init(void)
 358 {
 359         return i2c_add_driver(&as5011_driver);
 360 }
 361 module_init(as5011_init);
 362
 363 static void __exit as5011_exit(void)
 364 {
 365         i2c_del_driver(&as5011_driver);
 366 }
 367 module_exit(as5011_exit);