drivers/usb/misc/phidgetservo.c

   1 /*
   2  * USB PhidgetServo driver 1.0
   3  *
   4  * Copyright (C) 2004 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  * -23 < degrees < 203
  16  * 0 < minutes < 59
  17  *
  18  * CAUTION: Generally you should use 0 < degrees < 180 as anything else
  19  * is probably beyond the range of your servo and may damage it.
  20  */
  21
  22 #include <linux/config.h>
  23 #ifdef CONFIG_USB_DEBUG
  24 #define DEBUG   1
  25 #endif
  26 #include <linux/kernel.h>
  27 #include <linux/errno.h>
  28 #include <linux/init.h>
  29 #include <linux/slab.h>
  30 #include <linux/module.h>
  31 #include <linux/usb.h>
  32
  33 #define DRIVER_AUTHOR "Sean Young <sean@mess.org>"
  34 #define DRIVER_DESC "USB PhidgetServo Driver"
  35
  36 #define VENDOR_ID_GLAB                  0x06c2
  37 #define DEVICE_ID_4MOTOR_SERVO_30       0x0038
  38 #define DEVICE_ID_1MOTOR_SERVO_30       0x0039
  39
  40 #define VENDOR_ID_WISEGROUP             0x0925
  41 #define DEVICE_ID_1MOTOR_SERVO_20       0x8101
  42 #define DEVICE_ID_4MOTOR_SERVO_20       0x8104
  43
  44 static struct usb_device_id id_table[] = {
  45         {USB_DEVICE(VENDOR_ID_GLAB, DEVICE_ID_4MOTOR_SERVO_30)},
  46         {USB_DEVICE(VENDOR_ID_GLAB, DEVICE_ID_1MOTOR_SERVO_30)},
  47         {USB_DEVICE(VENDOR_ID_WISEGROUP, DEVICE_ID_4MOTOR_SERVO_20)},
  48         {USB_DEVICE(VENDOR_ID_WISEGROUP, DEVICE_ID_1MOTOR_SERVO_20)},
  49         {}
  50 };
  51
  52 MODULE_DEVICE_TABLE(usb, id_table);
  53
  54 struct phidget_servo {
  55         struct usb_device *udev;
  56         int version;
  57         int quad_servo;
  58         int pulse[4];
  59         int degrees[4];
  60         int minutes[4];
  61 };
  62
  63 static void
  64 change_position_v30(struct phidget_servo *servo, int servo_no, int degrees,
  65                                                                 int minutes)
  66 {
  67         int retval;
  68         unsigned char *buffer;
  69
  70         buffer = kmalloc(6, GFP_KERNEL);
  71         if (!buffer) {
  72                 dev_err(&servo->udev->dev, "%s - out of memory\n",
  73                         __FUNCTION__);
  74                 return;
  75         }
  76
  77         /*
  78          * pulse = 0 - 4095
  79          * angle = 0 - 180 degrees
  80          *
  81          * pulse = angle * 10.6 + 243.8
  82          */
  83         servo->pulse[servo_no] = ((degrees*60 + minutes)*106 + 2438*60)/600;
  84         servo->degrees[servo_no]= degrees;
  85         servo->minutes[servo_no]= minutes;
  86
  87         /*
  88          * The PhidgetServo v3.0 is controlled by sending 6 bytes,
  89          * 4 * 12 bits for each servo.
  90          *
  91          * low = lower 8 bits pulse
  92          * high = higher 4 bits pulse
  93          *
  94          * offset     bits
  95          * +---+-----------------+
  96          * | 0 |      low 0      |
  97          * +---+--------+--------+
  98          * | 1 | high 1 | high 0 |
  99          * +---+--------+--------+
 100          * | 2 |      low 1      |
 101          * +---+-----------------+
 102          * | 3 |      low 2      |
 103          * +---+--------+--------+
 104          * | 4 | high 3 | high 2 |
 105          * +---+--------+--------+
 106          * | 5 |      low 3      |
 107          * +---+-----------------+
 108          */
 109
 110         buffer[0] = servo->pulse[0] & 0xff;
 111         buffer[1] = (servo->pulse[0] >> 8 & 0x0f)
 112             | (servo->pulse[1] >> 4 & 0xf0);
 113         buffer[2] = servo->pulse[1] & 0xff;
 114         buffer[3] = servo->pulse[2] & 0xff;
 115         buffer[4] = (servo->pulse[2] >> 8 & 0x0f)
 116             | (servo->pulse[3] >> 4 & 0xf0);
 117         buffer[5] = servo->pulse[3] & 0xff;
 118
 119         dev_dbg(&servo->udev->dev,
 120                 "data: %02x %02x %02x %02x %02x %02x\n",
 121                 buffer[0], buffer[1], buffer[2],
 122                 buffer[3], buffer[4], buffer[5]);
 123
 124         retval = usb_control_msg(servo->udev,
 125                                  usb_sndctrlpipe(servo->udev, 0),
 126                                  0x09, 0x21, 0x0200, 0x0000, buffer, 6, 2 * HZ);
 127         if (retval != 6)
 128                 dev_err(&servo->udev->dev, "retval = %d\n", retval);
 129         kfree(buffer);
 130 }
 131
 132 static void
 133 change_position_v20(struct phidget_servo *servo, int servo_no, int degrees,
 134                                                                 int minutes)
 135 {
 136         int retval;
 137         unsigned char *buffer;
 138
 139         buffer = kmalloc(2, GFP_KERNEL);
 140         if (!buffer) {
 141                 dev_err(&servo->udev->dev, "%s - out of memory\n",
 142                         __FUNCTION__);
 143                 return;
 144         }
 145
 146         /*
 147          * angle = 0 - 180 degrees
 148          * pulse = angle + 23
 149          */
 150         servo->pulse[servo_no]= degrees + 23;
 151         servo->degrees[servo_no]= degrees;
 152         servo->minutes[servo_no]= 0;
 153
 154         /*
 155          * The PhidgetServo v2.0 is controlled by sending two bytes. The
 156          * first byte is the servo number xor'ed with 2:
 157          *
 158          * servo 0 = 2
 159          * servo 1 = 3
 160          * servo 2 = 0
 161          * servo 3 = 1
 162          *
 163          * The second byte is the position.
 164          */
 165
 166         buffer[0] = servo_no ^ 2;
 167         buffer[1] = servo->pulse[servo_no];
 168
 169         dev_dbg(&servo->udev->dev, "data: %02x %02x\n", buffer[0], buffer[1]);
 170
 171         retval = usb_control_msg(servo->udev,
 172                                  usb_sndctrlpipe(servo->udev, 0),
 173                                  0x09, 0x21, 0x0200, 0x0000, buffer, 2, 2 * HZ);
 174         if (retval != 2)
 175                 dev_err(&servo->udev->dev, "retval = %d\n", retval);
 176         kfree(buffer);
 177 }
 178
 179 #define show_set(value) \
 180 static ssize_t set_servo##value (struct device *dev,                    \
 181                                         const char *buf, size_t count)  \
 182 {                                                                       \
 183         int degrees, minutes;                                           \
 184         struct usb_interface *intf = to_usb_interface (dev);            \
 185         struct phidget_servo *servo = usb_get_intfdata (intf);          \
 186                                                                         \
 187         minutes = 0;                                                    \
 188         /* must at least convert degrees */                             \
 189         if (sscanf (buf, "%d.%d", &degrees, &minutes) < 1) {            \
 190                 return -EINVAL;                                         \
 191         }                                                               \
 192                                                                         \
 193         if (degrees < -23 || degrees > (180 + 23) ||                    \
 194             minutes < 0 || minutes > 59) {                              \
 195                 return -EINVAL;                                         \
 196         }                                                               \
 197                                                                         \
 198         if (servo->version >= 3)                                        \
 199                 change_position_v30 (servo, value, degrees, minutes);   \
 200         else                                                            \
 201                 change_position_v20 (servo, value, degrees, minutes);   \
 202                                                                         \
 203         return count;                                                   \
 204 }                                                                       \
 205                                                                         \
 206 static ssize_t show_servo##value (struct device *dev, char *buf)        \
 207 {                                                                       \
 208         struct usb_interface *intf = to_usb_interface (dev);            \
 209         struct phidget_servo *servo = usb_get_intfdata (intf);          \
 210                                                                         \
 211         return sprintf (buf, "%d.%02d\n", servo->degrees[value],        \
 212                                 servo->minutes[value]);                 \
 213 }                                                                       \
 214 static DEVICE_ATTR(servo##value, S_IWUGO | S_IRUGO,                     \
 215           show_servo##value, set_servo##value);
 216
 217 show_set(0);
 218 show_set(1);
 219 show_set(2);
 220 show_set(3);
 221
 222 static int
 223 servo_probe(struct usb_interface *interface, const struct usb_device_id *id)
 224 {
 225         struct usb_device *udev = interface_to_usbdev(interface);
 226         struct phidget_servo *dev = NULL;
 227
 228         dev = kmalloc(sizeof (struct phidget_servo), GFP_KERNEL);
 229         if (dev == NULL) {
 230                 dev_err(&interface->dev, "%s - out of memory\n", __FUNCTION__);
 231                 return -ENOMEM;
 232         }
 233         memset(dev, 0x00, sizeof (*dev));
 234
 235         dev->udev = usb_get_dev(udev);
 236         switch (udev->descriptor.idVendor) {
 237         case VENDOR_ID_WISEGROUP:
 238                 dev->version = 2;
 239                 break;
 240         case VENDOR_ID_GLAB:
 241                 dev->version = 3;
 242                 break;
 243         }
 244         switch (udev->descriptor.idProduct) {
 245         case DEVICE_ID_4MOTOR_SERVO_20:
 246         case DEVICE_ID_4MOTOR_SERVO_30:
 247                 dev->quad_servo = 1;
 248                 break;
 249         case DEVICE_ID_1MOTOR_SERVO_20:
 250         case DEVICE_ID_1MOTOR_SERVO_30:
 251                 dev->quad_servo = 0;
 252                 break;
 253         }
 254
 255         usb_set_intfdata(interface, dev);
 256
 257         device_create_file(&interface->dev, &dev_attr_servo0);
 258         if (dev->quad_servo) {
 259                 device_create_file(&interface->dev, &dev_attr_servo1);
 260                 device_create_file(&interface->dev, &dev_attr_servo2);
 261                 device_create_file(&interface->dev, &dev_attr_servo3);
 262         }
 263
 264         dev_info(&interface->dev, "USB %d-Motor PhidgetServo v%d.0 attached\n",
 265                  dev->quad_servo ? 4 : 1, dev->version);
 266         if (dev->version == 2)
 267                 dev_info(&interface->dev,
 268                          "WARNING: v2.0 not tested! Please report if it works.\n");
 269
 270         return 0;
 271 }
 272
 273 static void
 274 servo_disconnect(struct usb_interface *interface)
 275 {
 276         struct phidget_servo *dev;
 277
 278         dev = usb_get_intfdata(interface);
 279         usb_set_intfdata(interface, NULL);
 280
 281         device_remove_file(&interface->dev, &dev_attr_servo0);
 282         if (dev->quad_servo) {
 283                 device_remove_file(&interface->dev, &dev_attr_servo1);
 284                 device_remove_file(&interface->dev, &dev_attr_servo2);
 285                 device_remove_file(&interface->dev, &dev_attr_servo3);
 286         }
 287
 288         usb_put_dev(dev->udev);
 289
 290         kfree(dev);
 291
 292         dev_info(&interface->dev, "USB %d-Motor PhidgetServo v%d.0 detached\n",
 293                  dev->quad_servo ? 4 : 1, dev->version);
 294 }
 295
 296 static struct usb_driver servo_driver = {
 297         .owner = THIS_MODULE,
 298         .name = "phidgetservo",
 299         .probe = servo_probe,
 300         .disconnect = servo_disconnect,
 301         .id_table = id_table
 302 };
 303
 304 static int __init
 305 phidget_servo_init(void)
 306 {
 307         int retval = 0;
 308
 309         retval = usb_register(&servo_driver);
 310         if (retval)
 311                 err("usb_register failed. Error number %d", retval);
 312
 313         return retval;
 314 }
 315
 316 static void __exit
 317 phidget_servo_exit(void)
 318 {
 319         usb_deregister(&servo_driver);
 320 }
 321
 322 module_init(phidget_servo_init);
 323 module_exit(phidget_servo_exit);
 324
 325 MODULE_AUTHOR(DRIVER_AUTHOR);
 326 MODULE_DESCRIPTION(DRIVER_DESC);
 327 MODULE_LICENSE("GPL");