drivers/usb/misc/cypress_cy7c63.c

   1 /*
   2 * cypress_cy7c63.c
   3 *
   4 * Copyright (c) 2006-2007 Oliver Bock (bock@tfh-berlin.de)
   5 *
   6 *       This driver is based on the Cypress USB Driver by Marcus Maul
   7 *       (cyport) and the 2.0 version of Greg Kroah-Hartman's
   8 *       USB Skeleton driver.
   9 *
  10 *       This is a generic driver for the Cypress CY7C63xxx family.
  11 *       For the time being it enables you to read from and write to
  12 *       the single I/O ports of the device.
  13 *
  14 *       Supported vendors:      AK Modul-Bus Computer GmbH
  15 *                               (Firmware "Port-Chip")
  16 *
  17 *       Supported devices:      CY7C63001A-PC
  18 *                               CY7C63001C-PXC
  19 *                               CY7C63001C-SXC
  20 *
  21 *       Supported functions:    Read/Write Ports
  22 *
  23 *
  24 *       For up-to-date information please visit:
  25 *       http://www.obock.de/kernel/cypress
  26 *
  27 *       This program is free software; you can redistribute it and/or
  28 *       modify it under the terms of the GNU General Public License as
  29 *       published by the Free Software Foundation, version 2.
  30 */
  31
  32 #include <linux/init.h>
  33 #include <linux/module.h>
  34 #include <linux/kernel.h>
  35 #include <linux/slab.h>
  36 #include <linux/usb.h>
  37
  38 #define DRIVER_AUTHOR           "Oliver Bock (bock@tfh-berlin.de)"
  39 #define DRIVER_DESC             "Cypress CY7C63xxx USB driver"
  40
  41 #define CYPRESS_VENDOR_ID       0xa2c
  42 #define CYPRESS_PRODUCT_ID      0x8
  43
  44 #define CYPRESS_READ_PORT       0x4
  45 #define CYPRESS_WRITE_PORT      0x5
  46
  47 #define CYPRESS_READ_RAM        0x2
  48 #define CYPRESS_WRITE_RAM       0x3
  49 #define CYPRESS_READ_ROM        0x1
  50
  51 #define CYPRESS_READ_PORT_ID0   0
  52 #define CYPRESS_WRITE_PORT_ID0  0
  53 #define CYPRESS_READ_PORT_ID1   0x2
  54 #define CYPRESS_WRITE_PORT_ID1  1
  55
  56 #define CYPRESS_MAX_REQSIZE     8
  57
  58
  59 /* table of devices that work with this driver */
  60 static const struct usb_device_id cypress_table[] = {
  61         { USB_DEVICE(CYPRESS_VENDOR_ID, CYPRESS_PRODUCT_ID) },
  62         { }
  63 };
  64 MODULE_DEVICE_TABLE(usb, cypress_table);
  65
  66 /* structure to hold all of our device specific stuff */
  67 struct cypress {
  68         struct usb_device *     udev;
  69         unsigned char           port[2];
  70 };
  71
  72 /* used to send usb control messages to device */
  73 static int vendor_command(struct cypress *dev, unsigned char request,
  74                           unsigned char address, unsigned char data)
  75 {
  76         int retval = 0;
  77         unsigned int pipe;
  78         unsigned char *iobuf;
  79
  80         /* allocate some memory for the i/o buffer*/
  81         iobuf = kzalloc(CYPRESS_MAX_REQSIZE, GFP_KERNEL);
  82         if (!iobuf) {
  83                 dev_err(&dev->udev->dev, "Out of memory!\n");
  84                 retval = -ENOMEM;
  85                 goto error;
  86         }
  87
  88         dev_dbg(&dev->udev->dev, "Sending usb_control_msg (data: %d)\n", data);
  89
  90         /* prepare usb control message and send it upstream */
  91         pipe = usb_rcvctrlpipe(dev->udev, 0);
  92         retval = usb_control_msg(dev->udev, pipe, request,
  93                                  USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_OTHER,
  94                                  address, data, iobuf, CYPRESS_MAX_REQSIZE,
  95                                  USB_CTRL_GET_TIMEOUT);
  96
  97         /* store returned data (more READs to be added) */
  98         switch (request) {
  99                 case CYPRESS_READ_PORT:
 100                         if (address == CYPRESS_READ_PORT_ID0) {
 101                                 dev->port[0] = iobuf[1];
 102                                 dev_dbg(&dev->udev->dev,
 103                                         "READ_PORT0 returned: %d\n",
 104                                         dev->port[0]);
 105                         }
 106                         else if (address == CYPRESS_READ_PORT_ID1) {
 107                                 dev->port[1] = iobuf[1];
 108                                 dev_dbg(&dev->udev->dev,
 109                                         "READ_PORT1 returned: %d\n",
 110                                         dev->port[1]);
 111                         }
 112                         break;
 113         }
 114
 115         kfree(iobuf);
 116 error:
 117         return retval;
 118 }
 119
 120 /* write port value */
 121 static ssize_t write_port(struct device *dev, struct device_attribute *attr,
 122                           const char *buf, size_t count,
 123                           int port_num, int write_id)
 124 {
 125         int value = -1;
 126         int result = 0;
 127
 128         struct usb_interface *intf = to_usb_interface(dev);
 129         struct cypress *cyp = usb_get_intfdata(intf);
 130
 131         dev_dbg(&cyp->udev->dev, "WRITE_PORT%d called\n", port_num);
 132
 133         /* validate input data */
 134         if (sscanf(buf, "%d", &value) < 1) {
 135                 result = -EINVAL;
 136                 goto error;
 137         }
 138         if (value < 0 || value > 255) {
 139                 result = -EINVAL;
 140                 goto error;
 141         }
 142
 143         result = vendor_command(cyp, CYPRESS_WRITE_PORT, write_id,
 144                                 (unsigned char)value);
 145
 146         dev_dbg(&cyp->udev->dev, "Result of vendor_command: %d\n\n", result);
 147 error:
 148         return result < 0 ? result : count;
 149 }
 150
 151 /* attribute callback handler (write) */
 152 static ssize_t set_port0_handler(struct device *dev,
 153                                  struct device_attribute *attr,
 154                                  const char *buf, size_t count)
 155 {
 156         return write_port(dev, attr, buf, count, 0, CYPRESS_WRITE_PORT_ID0);
 157 }
 158
 159 /* attribute callback handler (write) */
 160 static ssize_t set_port1_handler(struct device *dev,
 161                                  struct device_attribute *attr,
 162                                  const char *buf, size_t count)
 163 {
 164         return write_port(dev, attr, buf, count, 1, CYPRESS_WRITE_PORT_ID1);
 165 }
 166
 167 /* read port value */
 168 static ssize_t read_port(struct device *dev, struct device_attribute *attr,
 169                          char *buf, int port_num, int read_id)
 170 {
 171         int result = 0;
 172
 173         struct usb_interface *intf = to_usb_interface(dev);
 174         struct cypress *cyp = usb_get_intfdata(intf);
 175
 176         dev_dbg(&cyp->udev->dev, "READ_PORT%d called\n", port_num);
 177
 178         result = vendor_command(cyp, CYPRESS_READ_PORT, read_id, 0);
 179
 180         dev_dbg(&cyp->udev->dev, "Result of vendor_command: %d\n\n", result);
 181
 182         return sprintf(buf, "%d", cyp->port[port_num]);
 183 }
 184
 185 /* attribute callback handler (read) */
 186 static ssize_t get_port0_handler(struct device *dev,
 187                                  struct device_attribute *attr, char *buf)
 188 {
 189         return read_port(dev, attr, buf, 0, CYPRESS_READ_PORT_ID0);
 190 }
 191
 192 /* attribute callback handler (read) */
 193 static ssize_t get_port1_handler(struct device *dev,
 194                                  struct device_attribute *attr, char *buf)
 195 {
 196         return read_port(dev, attr, buf, 1, CYPRESS_READ_PORT_ID1);
 197 }
 198
 199 static DEVICE_ATTR(port0, S_IWUGO | S_IRUGO,
 200                    get_port0_handler, set_port0_handler);
 201
 202 static DEVICE_ATTR(port1, S_IWUGO | S_IRUGO,
 203                    get_port1_handler, set_port1_handler);
 204
 205
 206 static int cypress_probe(struct usb_interface *interface,
 207                          const struct usb_device_id *id)
 208 {
 209         struct cypress *dev = NULL;
 210         int retval = -ENOMEM;
 211
 212         /* allocate memory for our device state and initialize it */
 213         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 214         if (dev == NULL) {
 215                 dev_err(&interface->dev, "Out of memory!\n");
 216                 goto error_mem;
 217         }
 218
 219         dev->udev = usb_get_dev(interface_to_usbdev(interface));
 220
 221         /* save our data pointer in this interface device */
 222         usb_set_intfdata(interface, dev);
 223
 224         /* create device attribute files */
 225         retval = device_create_file(&interface->dev, &dev_attr_port0);
 226         if (retval)
 227                 goto error;
 228         retval = device_create_file(&interface->dev, &dev_attr_port1);
 229         if (retval)
 230                 goto error;
 231
 232         /* let the user know that the device is now attached */
 233         dev_info(&interface->dev,
 234                  "Cypress CY7C63xxx device now attached\n");
 235         return 0;
 236
 237 error:
 238         device_remove_file(&interface->dev, &dev_attr_port0);
 239         device_remove_file(&interface->dev, &dev_attr_port1);
 240         usb_set_intfdata(interface, NULL);
 241         usb_put_dev(dev->udev);
 242         kfree(dev);
 243
 244 error_mem:
 245         return retval;
 246 }
 247
 248 static void cypress_disconnect(struct usb_interface *interface)
 249 {
 250         struct cypress *dev;
 251
 252         dev = usb_get_intfdata(interface);
 253
 254         /* remove device attribute files */
 255         device_remove_file(&interface->dev, &dev_attr_port0);
 256         device_remove_file(&interface->dev, &dev_attr_port1);
 257         /* the intfdata can be set to NULL only after the
 258          * device files have been removed */
 259         usb_set_intfdata(interface, NULL);
 260
 261         usb_put_dev(dev->udev);
 262
 263         dev_info(&interface->dev,
 264                  "Cypress CY7C63xxx device now disconnected\n");
 265
 266         kfree(dev);
 267 }
 268
 269 static struct usb_driver cypress_driver = {
 270         .name = "cypress_cy7c63",
 271         .probe = cypress_probe,
 272         .disconnect = cypress_disconnect,
 273         .id_table = cypress_table,
 274 };
 275
 276 static int __init cypress_init(void)
 277 {
 278         int result;
 279
 280         /* register this driver with the USB subsystem */
 281         result = usb_register(&cypress_driver);
 282         if (result)
 283                 printk(KERN_ERR KBUILD_MODNAME ": usb_register failed! "
 284                        "Error number: %d\n", result);
 285
 286         return result;
 287 }
 288
 289 static void __exit cypress_exit(void)
 290 {
 291         /* deregister this driver with the USB subsystem */
 292         usb_deregister(&cypress_driver);
 293 }
 294
 295 module_init(cypress_init);
 296 module_exit(cypress_exit);
 297
 298 MODULE_AUTHOR(DRIVER_AUTHOR);
 299 MODULE_DESCRIPTION(DRIVER_DESC);
 300
 301 MODULE_LICENSE("GPL");