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                 client->addr, I2C_M_IGNORE_NAK, 2, (uint8_t *)data
  89         };
  90         int error;
  91
  92         error = i2c_transfer(client->adapter, &msg, 1);
  93         return error < 0 ? error : 0;
  94 }
  95
  96 static int as5011_i2c_read(struct i2c_client *client,
  97                            uint8_t aregaddr, signed char *value)
  98 {
  99         uint8_t data[2] = { aregaddr };
 100         struct i2c_msg msg_set[2] = {
 101                 { client->addr, I2C_M_REV_DIR_ADDR, 1, (uint8_t *)data },
 102                 { client->addr, I2C_M_RD | I2C_M_NOSTART, 1, (uint8_t *)data }
 103         };
 104         int error;
 105
 106         error = i2c_transfer(client->adapter, msg_set, 2);
 107         if (error < 0)
 108                 return error;
 109
 110         *value = data[0] & 0x80 ? -1 * (1 + ~data[0]) : data[0];
 111         return 0;
 112 }
 113
 114 static irqreturn_t as5011_button_interrupt(int irq, void *dev_id)
 115 {
 116         struct as5011_device *as5011 = dev_id;
 117         int val = gpio_get_value_cansleep(as5011->button_gpio);
 118
 119         input_report_key(as5011->input_dev, BTN_JOYSTICK, !val);
 120         input_sync(as5011->input_dev);
 121
 122         return IRQ_HANDLED;
 123 }
 124
 125 static irqreturn_t as5011_axis_interrupt(int irq, void *dev_id)
 126 {
 127         struct as5011_device *as5011 = dev_id;
 128         int error;
 129         signed char x, y;
 130
 131         error = as5011_i2c_read(as5011->i2c_client, AS5011_X_RES_INT, &x);
 132         if (error < 0)
 133                 goto out;
 134
 135         error = as5011_i2c_read(as5011->i2c_client, AS5011_Y_RES_INT, &y);
 136         if (error < 0)
 137                 goto out;
 138
 139         input_report_abs(as5011->input_dev, ABS_X, x);
 140         input_report_abs(as5011->input_dev, ABS_Y, y);
 141         input_sync(as5011->input_dev);
 142
 143 out:
 144         return IRQ_HANDLED;
 145 }
 146
 147 static int __devinit as5011_configure_chip(struct as5011_device *as5011,
 148                                 const struct as5011_platform_data *plat_dat)
 149 {
 150         struct i2c_client *client = as5011->i2c_client;
 151         int error;
 152         signed char value;
 153
 154         /* chip soft reset */
 155         error = as5011_i2c_write(client, AS5011_CTRL1,
 156                                  AS5011_CTRL1_SOFT_RST);
 157         if (error < 0) {
 158                 dev_err(&client->dev, "Soft reset failed\n");
 159                 return error;
 160         }
 161
 162         mdelay(10);
 163
 164         error = as5011_i2c_write(client, AS5011_CTRL1,
 165                                  AS5011_CTRL1_LP_PULSED |
 166                                  AS5011_CTRL1_LP_ACTIVE |
 167                                  AS5011_CTRL1_INT_ACT_EN);
 168         if (error < 0) {
 169                 dev_err(&client->dev, "Power config failed\n");
 170                 return error;
 171         }
 172
 173         error = as5011_i2c_write(client, AS5011_CTRL2,
 174                                  AS5011_CTRL2_INV_SPINNING);
 175         if (error < 0) {
 176                 dev_err(&client->dev, "Can't invert spinning\n");
 177                 return error;
 178         }
 179
 180         /* write threshold */
 181         error = as5011_i2c_write(client, AS5011_XP, plat_dat->xp);
 182         if (error < 0) {
 183                 dev_err(&client->dev, "Can't write threshold\n");
 184                 return error;
 185         }
 186
 187         error = as5011_i2c_write(client, AS5011_XN, plat_dat->xn);
 188         if (error < 0) {
 189                 dev_err(&client->dev, "Can't write threshold\n");
 190                 return error;
 191         }
 192
 193         error = as5011_i2c_write(client, AS5011_YP, plat_dat->yp);
 194         if (error < 0) {
 195                 dev_err(&client->dev, "Can't write threshold\n");
 196                 return error;
 197         }
 198
 199         error = as5011_i2c_write(client, AS5011_YN, plat_dat->yn);
 200         if (error < 0) {
 201                 dev_err(&client->dev, "Can't write threshold\n");
 202                 return error;
 203         }
 204
 205         /* to free irq gpio in chip */
 206         error = as5011_i2c_read(client, AS5011_X_RES_INT, &value);
 207         if (error < 0) {
 208                 dev_err(&client->dev, "Can't read i2c X resolution value\n");
 209                 return error;
 210         }
 211
 212         return 0;
 213 }
 214
 215 static int __devinit as5011_probe(struct i2c_client *client,
 216                                 const struct i2c_device_id *id)
 217 {
 218         const struct as5011_platform_data *plat_data;
 219         struct as5011_device *as5011;
 220         struct input_dev *input_dev;
 221         int irq;
 222         int error;
 223
 224         plat_data = client->dev.platform_data;
 225         if (!plat_data)
 226                 return -EINVAL;
 227
 228         if (!plat_data->axis_irq) {
 229                 dev_err(&client->dev, "No axis IRQ?\n");
 230                 return -EINVAL;
 231         }
 232
 233         if (!i2c_check_functionality(client->adapter,
 234                                      I2C_FUNC_PROTOCOL_MANGLING)) {
 235                 dev_err(&client->dev,
 236                         "need i2c bus that supports protocol mangling\n");
 237                 return -ENODEV;
 238         }
 239
 240         as5011 = kmalloc(sizeof(struct as5011_device), GFP_KERNEL);
 241         input_dev = input_allocate_device();
 242         if (!as5011 || !input_dev) {
 243                 dev_err(&client->dev,
 244                         "Can't allocate memory for device structure\n");
 245                 error = -ENOMEM;
 246                 goto err_free_mem;
 247         }
 248
 249         as5011->i2c_client = client;
 250         as5011->input_dev = input_dev;
 251         as5011->button_gpio = plat_data->button_gpio;
 252         as5011->axis_irq = plat_data->axis_irq;
 253
 254         input_dev->name = "Austria Microsystem as5011 joystick";
 255         input_dev->id.bustype = BUS_I2C;
 256         input_dev->dev.parent = &client->dev;
 257
 258         __set_bit(EV_KEY, input_dev->evbit);
 259         __set_bit(EV_ABS, input_dev->evbit);
 260         __set_bit(BTN_JOYSTICK, input_dev->keybit);
 261
 262         input_set_abs_params(input_dev, ABS_X,
 263                 AS5011_MIN_AXIS, AS5011_MAX_AXIS, AS5011_FUZZ, AS5011_FLAT);
 264         input_set_abs_params(as5011->input_dev, ABS_Y,
 265                 AS5011_MIN_AXIS, AS5011_MAX_AXIS, AS5011_FUZZ, AS5011_FLAT);
 266
 267         error = gpio_request(as5011->button_gpio, "AS5011 button");
 268         if (error < 0) {
 269                 dev_err(&client->dev, "Failed to request button gpio\n");
 270                 goto err_free_mem;
 271         }
 272
 273         irq = gpio_to_irq(as5011->button_gpio);
 274         if (irq < 0) {
 275                 dev_err(&client->dev,
 276                         "Failed to get irq number for button gpio\n");
 277                 goto err_free_button_gpio;
 278         }
 279
 280         as5011->button_irq = irq;
 281
 282         error = request_threaded_irq(as5011->button_irq,
 283                                      NULL, as5011_button_interrupt,
 284                                      IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
 285                                      "as5011_button", as5011);
 286         if (error < 0) {
 287                 dev_err(&client->dev,
 288                         "Can't allocate button irq %d\n", as5011->button_irq);
 289                 goto err_free_button_gpio;
 290         }
 291
 292         error = as5011_configure_chip(as5011, plat_data);
 293         if (error)
 294                 goto err_free_button_irq;
 295
 296         error = request_threaded_irq(as5011->axis_irq, NULL,
 297                                      as5011_axis_interrupt,
 298                                      plat_data->axis_irqflags,
 299                                      "as5011_joystick", as5011);
 300         if (error) {
 301                 dev_err(&client->dev,
 302                         "Can't allocate axis irq %d\n", plat_data->axis_irq);
 303                 goto err_free_button_irq;
 304         }
 305
 306         error = input_register_device(as5011->input_dev);
 307         if (error) {
 308                 dev_err(&client->dev, "Failed to register input device\n");
 309                 goto err_free_axis_irq;
 310         }
 311
 312         i2c_set_clientdata(client, as5011);
 313
 314         return 0;
 315
 316 err_free_axis_irq:
 317         free_irq(as5011->axis_irq, as5011);
 318 err_free_button_irq:
 319         free_irq(as5011->button_irq, as5011);
 320 err_free_button_gpio:
 321         gpio_free(as5011->button_gpio);
 322 err_free_mem:
 323         input_free_device(input_dev);
 324         kfree(as5011);
 325
 326         return error;
 327 }
 328
 329 static int __devexit as5011_remove(struct i2c_client *client)
 330 {
 331         struct as5011_device *as5011 = i2c_get_clientdata(client);
 332
 333         free_irq(as5011->axis_irq, as5011);
 334         free_irq(as5011->button_irq, as5011);
 335         gpio_free(as5011->button_gpio);
 336
 337         input_unregister_device(as5011->input_dev);
 338         kfree(as5011);
 339
 340         return 0;
 341 }
 342
 343 static const struct i2c_device_id as5011_id[] = {
 344         { MODULE_DEVICE_ALIAS, 0 },
 345         { }
 346 };
 347 MODULE_DEVICE_TABLE(i2c, as5011_id);
 348
 349 static struct i2c_driver as5011_driver = {
 350         .driver = {
 351                 .name = "as5011",
 352         },
 353         .probe          = as5011_probe,
 354         .remove         = __devexit_p(as5011_remove),
 355         .id_table       = as5011_id,
 356 };
 357
 358 module_i2c_driver(as5011_driver);