drivers/usb/misc/phidgetservo.c

   1 /*
   2  * USB PhidgetServo driver 1.0
   3  *
   4  * Copyright (C) 2004, 2006 Sean Young <sean@mess.org>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This is a driver for the USB PhidgetServo version 2.0 and 3.0 servo
  12  * controllers available at: http://www.phidgets.com/
  13  *
  14  * Note that the driver takes input as: degrees.minutes
  15  *
  16  * CAUTION: Generally you should use 0 < degrees < 180 as anything else
  17  * is probably beyond the range of your servo and may damage it.
  18  */
  19
  20 #include <linux/kernel.h>
  21 #include <linux/errno.h>
  22 #include <linux/init.h>
  23 #include <linux/slab.h>
  24 #include <linux/module.h>
  25 #include <linux/usb.h>
  26
  27 #include "phidget.h"
  28
  29 #define DRIVER_AUTHOR "Sean Young <sean@mess.org>"
  30 #define DRIVER_DESC "USB PhidgetServo Driver"
  31
  32 #define VENDOR_ID_GLAB                          0x06c2
  33 #define DEVICE_ID_GLAB_PHIDGETSERVO_QUAD        0x0038
  34 #define DEVICE_ID_GLAB_PHIDGETSERVO_UNI         0x0039
  35
  36 #define VENDOR_ID_WISEGROUP                     0x0925
  37 #define VENDOR_ID_WISEGROUP_PHIDGETSERVO_QUAD   0x8101
  38 #define VENDOR_ID_WISEGROUP_PHIDGETSERVO_UNI    0x8104
  39
  40 #define SERVO_VERSION_30                        0x01
  41 #define SERVO_COUNT_QUAD                        0x02
  42
  43 static struct usb_device_id id_table[] = {
  44         {
  45                 USB_DEVICE(VENDOR_ID_GLAB, DEVICE_ID_GLAB_PHIDGETSERVO_QUAD),
  46                 .driver_info = SERVO_VERSION_30 | SERVO_COUNT_QUAD
  47         },
  48         {
  49                 USB_DEVICE(VENDOR_ID_GLAB, DEVICE_ID_GLAB_PHIDGETSERVO_UNI),
  50                 .driver_info = SERVO_VERSION_30
  51         },
  52         {
  53                 USB_DEVICE(VENDOR_ID_WISEGROUP,
  54                                 VENDOR_ID_WISEGROUP_PHIDGETSERVO_QUAD),
  55                 .driver_info = SERVO_COUNT_QUAD
  56         },
  57         {
  58                 USB_DEVICE(VENDOR_ID_WISEGROUP,
  59                                 VENDOR_ID_WISEGROUP_PHIDGETSERVO_UNI),
  60                 .driver_info = 0
  61         },
  62         {}
  63 };
  64
  65 MODULE_DEVICE_TABLE(usb, id_table);
  66
  67 static int unsigned long device_no;
  68
  69 struct phidget_servo {
  70         struct usb_device *udev;
  71         struct device *dev;
  72         int dev_no;
  73         ulong type;
  74         int pulse[4];
  75         int degrees[4];
  76         int minutes[4];
  77 };
  78
  79 static int
  80 change_position_v30(struct phidget_servo *servo, int servo_no, int degrees,
  81                                                                 int minutes)
  82 {
  83         int retval;
  84         unsigned char *buffer;
  85
  86         if (degrees < -23 || degrees > 362)
  87                 return -EINVAL;
  88
  89         buffer = kmalloc(6, GFP_KERNEL);
  90         if (!buffer) {
  91                 dev_err(&servo->udev->dev, "%s - out of memory\n",
  92                         __func__);
  93                 return -ENOMEM;
  94         }
  95
  96         /*
  97          * pulse = 0 - 4095
  98          * angle = 0 - 180 degrees
  99          *
 100          * pulse = angle * 10.6 + 243.8
 101          */
 102         servo->pulse[servo_no] = ((degrees*60 + minutes)*106 + 2438*60)/600;
 103         servo->degrees[servo_no]= degrees;
 104         servo->minutes[servo_no]= minutes;
 105
 106         /*
 107          * The PhidgetServo v3.0 is controlled by sending 6 bytes,
 108          * 4 * 12 bits for each servo.
 109          *
 110          * low = lower 8 bits pulse
 111          * high = higher 4 bits pulse
 112          *
 113          * offset     bits
 114          * +---+-----------------+
 115          * | 0 |      low 0      |
 116          * +---+--------+--------+
 117          * | 1 | high 1 | high 0 |
 118          * +---+--------+--------+
 119          * | 2 |      low 1      |
 120          * +---+-----------------+
 121          * | 3 |      low 2      |
 122          * +---+--------+--------+
 123          * | 4 | high 3 | high 2 |
 124          * +---+--------+--------+
 125          * | 5 |      low 3      |
 126          * +---+-----------------+
 127          */
 128
 129         buffer[0] = servo->pulse[0] & 0xff;
 130         buffer[1] = (servo->pulse[0] >> 8 & 0x0f)
 131             | (servo->pulse[1] >> 4 & 0xf0);
 132         buffer[2] = servo->pulse[1] & 0xff;
 133         buffer[3] = servo->pulse[2] & 0xff;
 134         buffer[4] = (servo->pulse[2] >> 8 & 0x0f)
 135             | (servo->pulse[3] >> 4 & 0xf0);
 136         buffer[5] = servo->pulse[3] & 0xff;
 137
 138         dev_dbg(&servo->udev->dev,
 139                 "data: %02x %02x %02x %02x %02x %02x\n",
 140                 buffer[0], buffer[1], buffer[2],
 141                 buffer[3], buffer[4], buffer[5]);
 142
 143         retval = usb_control_msg(servo->udev,
 144                                  usb_sndctrlpipe(servo->udev, 0),
 145                                  0x09, 0x21, 0x0200, 0x0000, buffer, 6, 2000);
 146
 147         kfree(buffer);
 148
 149         return retval;
 150 }
 151
 152 static int
 153 change_position_v20(struct phidget_servo *servo, int servo_no, int degrees,
 154                                                                 int minutes)
 155 {
 156         int retval;
 157         unsigned char *buffer;
 158
 159         if (degrees < -23 || degrees > 278)
 160                 return -EINVAL;
 161
 162         buffer = kmalloc(2, GFP_KERNEL);
 163         if (!buffer) {
 164                 dev_err(&servo->udev->dev, "%s - out of memory\n",
 165                         __func__);
 166                 return -ENOMEM;
 167         }
 168
 169         /*
 170          * angle = 0 - 180 degrees
 171          * pulse = angle + 23
 172          */
 173         servo->pulse[servo_no]= degrees + 23;
 174         servo->degrees[servo_no]= degrees;
 175         servo->minutes[servo_no]= 0;
 176
 177         /*
 178          * The PhidgetServo v2.0 is controlled by sending two bytes. The
 179          * first byte is the servo number xor'ed with 2:
 180          *
 181          * servo 0 = 2
 182          * servo 1 = 3
 183          * servo 2 = 0
 184          * servo 3 = 1
 185          *
 186          * The second byte is the position.
 187          */
 188
 189         buffer[0] = servo_no ^ 2;
 190         buffer[1] = servo->pulse[servo_no];
 191
 192         dev_dbg(&servo->udev->dev, "data: %02x %02x\n", buffer[0], buffer[1]);
 193
 194         retval = usb_control_msg(servo->udev,
 195                                  usb_sndctrlpipe(servo->udev, 0),
 196                                  0x09, 0x21, 0x0200, 0x0000, buffer, 2, 2000);
 197
 198         kfree(buffer);
 199
 200         return retval;
 201 }
 202
 203 #define show_set(value) \
 204 static ssize_t set_servo##value (struct device *dev,                    \
 205                                         struct device_attribute *attr,  \
 206                                         const char *buf, size_t count)  \
 207 {                                                                       \
 208         int degrees, minutes, retval;                                   \
 209         struct phidget_servo *servo = dev_get_drvdata(dev);             \
 210                                                                         \
 211         minutes = 0;                                                    \
 212         /* must at least convert degrees */                             \
 213         if (sscanf(buf, "%d.%d", &degrees, &minutes) < 1) {             \
 214                 return -EINVAL;                                         \
 215         }                                                               \
 216                                                                         \
 217         if (minutes < 0 || minutes > 59)                                \
 218                 return -EINVAL;                                         \
 219                                                                         \
 220         if (servo->type & SERVO_VERSION_30)                             \
 221                 retval = change_position_v30(servo, value, degrees,     \
 222                                                         minutes);       \
 223         else                                                            \
 224                 retval = change_position_v20(servo, value, degrees,     \
 225                                                         minutes);       \
 226                                                                         \
 227         return retval < 0 ? retval : count;                             \
 228 }                                                                       \
 229                                                                         \
 230 static ssize_t show_servo##value (struct device *dev,                   \
 231                                         struct device_attribute *attr,  \
 232                                         char *buf)                      \
 233 {                                                                       \
 234         struct phidget_servo *servo = dev_get_drvdata(dev);             \
 235                                                                         \
 236         return sprintf(buf, "%d.%02d\n", servo->degrees[value],         \
 237                                 servo->minutes[value]);                 \
 238 }
 239
 240 #define servo_attr(value)                                               \
 241         __ATTR(servo##value, S_IWUGO | S_IRUGO,                         \
 242                 show_servo##value, set_servo##value)
 243 show_set(0);
 244 show_set(1);
 245 show_set(2);
 246 show_set(3);
 247
 248 static struct device_attribute dev_attrs[] = {
 249         servo_attr(0), servo_attr(1), servo_attr(2), servo_attr(3)
 250 };
 251
 252 static int
 253 servo_probe(struct usb_interface *interface, const struct usb_device_id *id)
 254 {
 255         struct usb_device *udev = interface_to_usbdev(interface);
 256         struct phidget_servo *dev;
 257         int bit, value, rc;
 258         int servo_count, i;
 259
 260         dev = kzalloc(sizeof (struct phidget_servo), GFP_KERNEL);
 261         if (dev == NULL) {
 262                 dev_err(&interface->dev, "%s - out of memory\n", __func__);
 263                 rc = -ENOMEM;
 264                 goto out;
 265         }
 266
 267         dev->udev = usb_get_dev(udev);
 268         dev->type = id->driver_info;
 269         dev->dev_no = -1;
 270         usb_set_intfdata(interface, dev);
 271
 272         do {
 273                 bit = find_first_zero_bit(&device_no, sizeof(device_no));
 274                 value = test_and_set_bit(bit, &device_no);
 275         } while (value);
 276         dev->dev_no = bit;
 277
 278         dev->dev = device_create(phidget_class, &dev->udev->dev, MKDEV(0, 0),
 279                                  dev, "servo%d", dev->dev_no);
 280         if (IS_ERR(dev->dev)) {
 281                 rc = PTR_ERR(dev->dev);
 282                 dev->dev = NULL;
 283                 goto out;
 284         }
 285
 286         servo_count = dev->type & SERVO_COUNT_QUAD ? 4 : 1;
 287
 288         for (i=0; i<servo_count; i++) {
 289                 rc = device_create_file(dev->dev, &dev_attrs[i]);
 290                 if (rc)
 291                         goto out2;
 292         }
 293
 294         dev_info(&interface->dev, "USB %d-Motor PhidgetServo v%d.0 attached\n",
 295                 servo_count, dev->type & SERVO_VERSION_30 ? 3 : 2);
 296
 297         if (!(dev->type & SERVO_VERSION_30))
 298                 dev_info(&interface->dev,
 299                          "WARNING: v2.0 not tested! Please report if it works.\n");
 300
 301         return 0;
 302 out2:
 303         while (i-- > 0)
 304                 device_remove_file(dev->dev, &dev_attrs[i]);
 305 out:
 306         if (dev) {
 307                 if (dev->dev)
 308                         device_unregister(dev->dev);
 309                 if (dev->dev_no >= 0)
 310                         clear_bit(dev->dev_no, &device_no);
 311
 312                 kfree(dev);
 313         }
 314
 315         return rc;
 316 }
 317
 318 static void
 319 servo_disconnect(struct usb_interface *interface)
 320 {
 321         struct phidget_servo *dev;
 322         int servo_count, i;
 323
 324         dev = usb_get_intfdata(interface);
 325         usb_set_intfdata(interface, NULL);
 326
 327         if (!dev)
 328                 return;
 329
 330         servo_count = dev->type & SERVO_COUNT_QUAD ? 4 : 1;
 331
 332         for (i=0; i<servo_count; i++)
 333                 device_remove_file(dev->dev, &dev_attrs[i]);
 334
 335         device_unregister(dev->dev);
 336         usb_put_dev(dev->udev);
 337
 338         dev_info(&interface->dev, "USB %d-Motor PhidgetServo v%d.0 detached\n",
 339                 servo_count, dev->type & SERVO_VERSION_30 ? 3 : 2);
 340
 341         clear_bit(dev->dev_no, &device_no);
 342         kfree(dev);
 343 }
 344
 345 static struct usb_driver servo_driver = {
 346         .name = "phidgetservo",
 347         .probe = servo_probe,
 348         .disconnect = servo_disconnect,
 349         .id_table = id_table
 350 };
 351
 352 static int __init
 353 phidget_servo_init(void)
 354 {
 355         int retval;
 356
 357         retval = usb_register(&servo_driver);
 358         if (retval)
 359                 err("usb_register failed. Error number %d", retval);
 360
 361         return retval;
 362 }
 363
 364 static void __exit
 365 phidget_servo_exit(void)
 366 {
 367         usb_deregister(&servo_driver);
 368 }
 369
 370 module_init(phidget_servo_init);
 371 module_exit(phidget_servo_exit);
 372
 373 MODULE_AUTHOR(DRIVER_AUTHOR);
 374 MODULE_DESCRIPTION(DRIVER_DESC);
 375 MODULE_LICENSE("GPL");