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); 373