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