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   1 /*
   2  * Copyright © 2008 Keith Packard <keithp@keithp.com>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along
  15  * with this program; if not, write to the Free Software Foundation, Inc.,
  16  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  17  */
  18
  19 #include <stdio.h>
  20 #include <errno.h>
  21 #include <stdlib.h>
  22 #include <unistd.h>
  23 #include "cp-usb-async.h"
  24 #include "ccdbg-debug.h"
  25
  26 #define MAX_OUTSTANDING         256
  27 #define CP_TIMEOUT              1000    /* ms */
  28
  29 struct cp_usb_packet {
  30         struct libusb_transfer  *transfer;
  31         enum { packet_read, packet_write } direction;
  32         unsigned char           data[9];
  33         uint8_t                 *valuep;
  34 };
  35
  36 struct cp_usb_async {
  37         libusb_context          *ctx;
  38         libusb_device_handle    *handle;
  39         struct cp_usb_packet    packet[MAX_OUTSTANDING];
  40         int                     p, ack;
  41 };
  42
  43 struct cp_usb_async *
  44 cp_usb_async_open(void)
  45 {
  46         struct cp_usb_async *cp;
  47         int ret;
  48
  49         cp = calloc(sizeof (struct cp_usb_async), 1);
  50         if (!cp)
  51                 return NULL;
  52         ret = libusb_init(&cp->ctx);
  53         if (ret) {
  54                 free(cp);
  55                 return NULL;
  56         }
  57         cp->handle = libusb_open_device_with_vid_pid(cp->ctx,
  58                                                      0x10c4, 0xea60);
  59         if (!cp->handle) {
  60                 libusb_exit(cp->ctx);
  61                 free(cp);
  62                 return NULL;
  63         }
  64         return cp;
  65 }
  66
  67 void
  68 cp_usb_async_close(struct cp_usb_async *cp)
  69 {
  70         libusb_close(cp->handle);
  71         libusb_exit(cp->ctx);
  72         free(cp);
  73 }
  74
  75 static void
  76 cp_usb_async_transfer_callback(struct libusb_transfer *transfer)
  77 {
  78         struct cp_usb_async *cp = transfer->user_data;
  79         int p;
  80
  81         for (p = 0; p < cp->p; p++)
  82                 if (cp->packet[p].transfer == transfer)
  83                         break;
  84         if (p == cp->p) {
  85                 fprintf(stderr, "unknown transfer\n");
  86                 return;
  87         }
  88         switch (cp->packet[p].direction) {
  89         case packet_read:
  90                 ccdbg_debug(CC_DEBUG_USB_ASYNC, "ack read %d 0x%02x\n",
  91                             p, cp->packet[p].data[8]);
  92                 *cp->packet[p].valuep = cp->packet[p].data[8];
  93                 break;
  94         case packet_write:
  95                 ccdbg_debug(CC_DEBUG_USB_ASYNC, "ack write %d\n", p);
  96                 break;
  97         }
  98         if (p > cp->ack)
  99                 cp->ack = p;
 100 }
 101
 102 void
 103 cp_usb_async_write(struct cp_usb_async *cp, uint8_t mask, uint8_t value)
 104 {
 105         int     p;
 106         uint16_t gpio_set = ((uint16_t) value << 8) | mask;
 107         int     ret;
 108
 109         if (cp->p == MAX_OUTSTANDING)
 110                 cp_usb_async_sync(cp);
 111         p = cp->p;
 112         if (!cp->packet[p].transfer)
 113                 cp->packet[p].transfer = libusb_alloc_transfer(0);
 114         cp->packet[p].direction = packet_write;
 115         libusb_fill_control_setup(cp->packet[p].data,
 116                                   0x40,                 /* request */
 117                                   0xff,                 /* request type */
 118                                   0x37e1,               /* value */
 119                                   gpio_set,             /* index */
 120                                   0);                   /* length */
 121
 122         libusb_fill_control_transfer(cp->packet[p].transfer,
 123                                      cp->handle,
 124                                      cp->packet[p].data,
 125                                      cp_usb_async_transfer_callback,
 126                                      cp,
 127                                      CP_TIMEOUT);
 128         ccdbg_debug(CC_DEBUG_USB_ASYNC, "Write packet %d 0x%x 0x%x\n", p, mask, value);
 129         ret = libusb_submit_transfer(cp->packet[p].transfer);
 130         if (ret)
 131                 fprintf(stderr, "libusb_submit_transfer failed %d\n", ret);
 132         cp->p++;
 133 }
 134
 135 void
 136 cp_usb_async_read(struct cp_usb_async *cp, uint8_t *valuep)
 137 {
 138         int     p;
 139         int     ret;
 140
 141         if (cp->p == MAX_OUTSTANDING)
 142                 cp_usb_async_sync(cp);
 143         p = cp->p;
 144         if (!cp->packet[p].transfer)
 145                 cp->packet[p].transfer = libusb_alloc_transfer(0);
 146         cp->packet[p].valuep = valuep;
 147         cp->packet[p].direction = packet_read;
 148         libusb_fill_control_setup(cp->packet[p].data,
 149                                   0xc0,                 /* request */
 150                                   0xff,                 /* request type */
 151                                   0x00c2,               /* value */
 152                                   0,                    /* index */
 153                                   1);                   /* length */
 154
 155         libusb_fill_control_transfer(cp->packet[p].transfer,
 156                                      cp->handle,
 157                                      cp->packet[p].data,
 158                                      cp_usb_async_transfer_callback,
 159                                      cp,
 160                                      CP_TIMEOUT);
 161         ccdbg_debug(CC_DEBUG_USB_ASYNC, "Read packet %d\n", p);
 162         ret = libusb_submit_transfer(cp->packet[p].transfer);
 163         if (ret)
 164                 fprintf(stderr, "libusb_submit_transfer failed %d\n", ret);
 165         cp->p++;
 166 }
 167
 168 void
 169 cp_usb_async_sync(struct cp_usb_async *cp)
 170 {
 171         while (cp->ack < cp->p - 1) {
 172                 libusb_handle_events(cp->ctx);
 173         }
 174         cp->p = 0;
 175         cp->ack = 0;
 176 }