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