drivers/usb/misc/cypress_cy7c63.c

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