1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (c) 2010, 2011 Fabien Marteau <fabien.marteau@armadeus.com> 4 * Sponsored by ARMadeus Systems 5 * 6 * Driver for Austria Microsystems joysticks AS5011 7 * 8 * TODO: 9 * - Power on the chip when open() and power down when close() 10 * - Manage power mode 11 */ 12 13 #include <linux/i2c.h> 14 #include <linux/interrupt.h> 15 #include <linux/input.h> 16 #include <linux/gpio/consumer.h> 17 #include <linux/delay.h> 18 #include <linux/input/as5011.h> 19 #include <linux/slab.h> 20 #include <linux/module.h> 21 22 #define DRIVER_DESC "Driver for Austria Microsystems AS5011 joystick" 23 #define MODULE_DEVICE_ALIAS "as5011" 24 25 MODULE_AUTHOR("Fabien Marteau <fabien.marteau@armadeus.com>"); 26 MODULE_DESCRIPTION(DRIVER_DESC); 27 MODULE_LICENSE("GPL"); 28 29 /* registers */ 30 #define AS5011_CTRL1 0x76 31 #define AS5011_CTRL2 0x75 32 #define AS5011_XP 0x43 33 #define AS5011_XN 0x44 34 #define AS5011_YP 0x53 35 #define AS5011_YN 0x54 36 #define AS5011_X_REG 0x41 37 #define AS5011_Y_REG 0x42 38 #define AS5011_X_RES_INT 0x51 39 #define AS5011_Y_RES_INT 0x52 40 41 /* CTRL1 bits */ 42 #define AS5011_CTRL1_LP_PULSED 0x80 43 #define AS5011_CTRL1_LP_ACTIVE 0x40 44 #define AS5011_CTRL1_LP_CONTINUE 0x20 45 #define AS5011_CTRL1_INT_WUP_EN 0x10 46 #define AS5011_CTRL1_INT_ACT_EN 0x08 47 #define AS5011_CTRL1_EXT_CLK_EN 0x04 48 #define AS5011_CTRL1_SOFT_RST 0x02 49 #define AS5011_CTRL1_DATA_VALID 0x01 50 51 /* CTRL2 bits */ 52 #define AS5011_CTRL2_EXT_SAMPLE_EN 0x08 53 #define AS5011_CTRL2_RC_BIAS_ON 0x04 54 #define AS5011_CTRL2_INV_SPINNING 0x02 55 56 #define AS5011_MAX_AXIS 80 57 #define AS5011_MIN_AXIS (-80) 58 #define AS5011_FUZZ 8 59 #define AS5011_FLAT 40 60 61 struct as5011_device { 62 struct input_dev *input_dev; 63 struct i2c_client *i2c_client; 64 struct gpio_desc *button_gpiod; 65 unsigned int button_irq; 66 unsigned int axis_irq; 67 }; 68 69 static int as5011_i2c_write(struct i2c_client *client, 70 uint8_t aregaddr, 71 uint8_t avalue) 72 { 73 uint8_t data[2] = { aregaddr, avalue }; 74 struct i2c_msg msg = { 75 .addr = client->addr, 76 .flags = I2C_M_IGNORE_NAK, 77 .len = 2, 78 .buf = (uint8_t *)data 79 }; 80 int error; 81 82 error = i2c_transfer(client->adapter, &msg, 1); 83 return error < 0 ? error : 0; 84 } 85 86 static int as5011_i2c_read(struct i2c_client *client, 87 uint8_t aregaddr, signed char *value) 88 { 89 uint8_t data[2] = { aregaddr }; 90 struct i2c_msg msg_set[2] = { 91 { 92 .addr = client->addr, 93 .flags = I2C_M_REV_DIR_ADDR, 94 .len = 1, 95 .buf = (uint8_t *)data 96 }, 97 { 98 .addr = client->addr, 99 .flags = I2C_M_RD | I2C_M_NOSTART, 100 .len = 1, 101 .buf = (uint8_t *)data 102 } 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 = gpiod_get_value_cansleep(as5011->button_gpiod); 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 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 as5011_probe(struct i2c_client *client) 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 = dev_get_platdata(&client->dev); 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_NOSTART | 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->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 input_set_capability(input_dev, EV_KEY, BTN_JOYSTICK); 258 259 input_set_abs_params(input_dev, ABS_X, 260 AS5011_MIN_AXIS, AS5011_MAX_AXIS, AS5011_FUZZ, AS5011_FLAT); 261 input_set_abs_params(as5011->input_dev, ABS_Y, 262 AS5011_MIN_AXIS, AS5011_MAX_AXIS, AS5011_FUZZ, AS5011_FLAT); 263 264 as5011->button_gpiod = devm_gpiod_get(&client->dev, NULL, GPIOD_IN); 265 if (IS_ERR(as5011->button_gpiod)) { 266 error = PTR_ERR(as5011->button_gpiod); 267 dev_err(&client->dev, "Failed to request button GPIO\n"); 268 goto err_free_mem; 269 } 270 gpiod_set_consumer_name(as5011->button_gpiod, "AS5011 button"); 271 272 irq = gpiod_to_irq(as5011->button_gpiod); 273 if (irq < 0) { 274 dev_err(&client->dev, 275 "Failed to get irq number for button gpio\n"); 276 error = irq; 277 goto err_free_mem; 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 | 285 IRQF_TRIGGER_FALLING | IRQF_ONESHOT, 286 "as5011_button", as5011); 287 if (error < 0) { 288 dev_err(&client->dev, 289 "Can't allocate button irq %d\n", as5011->button_irq); 290 goto err_free_mem; 291 } 292 293 error = as5011_configure_chip(as5011, plat_data); 294 if (error) 295 goto err_free_button_irq; 296 297 error = request_threaded_irq(as5011->axis_irq, NULL, 298 as5011_axis_interrupt, 299 plat_data->axis_irqflags | IRQF_ONESHOT, 300 "as5011_joystick", as5011); 301 if (error) { 302 dev_err(&client->dev, 303 "Can't allocate axis irq %d\n", plat_data->axis_irq); 304 goto err_free_button_irq; 305 } 306 307 error = input_register_device(as5011->input_dev); 308 if (error) { 309 dev_err(&client->dev, "Failed to register input device\n"); 310 goto err_free_axis_irq; 311 } 312 313 i2c_set_clientdata(client, as5011); 314 315 return 0; 316 317 err_free_axis_irq: 318 free_irq(as5011->axis_irq, as5011); 319 err_free_button_irq: 320 free_irq(as5011->button_irq, as5011); 321 err_free_mem: 322 input_free_device(input_dev); 323 kfree(as5011); 324 325 return error; 326 } 327 328 static void 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); 334 335 input_unregister_device(as5011->input_dev); 336 kfree(as5011); 337 } 338 339 static const struct i2c_device_id as5011_id[] = { 340 { MODULE_DEVICE_ALIAS, 0 }, 341 { } 342 }; 343 MODULE_DEVICE_TABLE(i2c, as5011_id); 344 345 static struct i2c_driver as5011_driver = { 346 .driver = { 347 .name = "as5011", 348 }, 349 .probe = as5011_probe, 350 .remove = as5011_remove, 351 .id_table = as5011_id, 352 }; 353 354 module_i2c_driver(as5011_driver); 355