firmware/usbstack/usb_serial.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2007 by Christian Gmeiner
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  18  * KIND, either express or implied.
  19  *
  20  ****************************************************************************/
  21 #include "string.h"
  22 #include "system.h"
  23 #include "usb_core.h"
  24 #include "usb_drv.h"
  25 #include "kernel.h"
  26 #include "usb_serial.h"
  27
  28 //#define LOGF_ENABLE
  29 #include "logf.h"
  30
  31 #ifdef USB_SERIAL
  32
  33 /* serial interface */
  34 static struct usb_interface_descriptor __attribute__((aligned(2)))
  35                                 interface_descriptor =
  36 {
  37     .bLength            = sizeof(struct usb_interface_descriptor),
  38     .bDescriptorType    = USB_DT_INTERFACE,
  39     .bInterfaceNumber   = 0,
  40     .bAlternateSetting  = 0,
  41     .bNumEndpoints      = 2,
  42     .bInterfaceClass    = USB_CLASS_CDC_DATA,
  43     .bInterfaceSubClass = 0,
  44     .bInterfaceProtocol = 0,
  45     .iInterface         = 0
  46 };
  47
  48
  49 static struct usb_endpoint_descriptor __attribute__((aligned(2))) endpoint_descriptor =
  50 {
  51     .bLength          = sizeof(struct usb_endpoint_descriptor),
  52     .bDescriptorType  = USB_DT_ENDPOINT,
  53     .bEndpointAddress = 0,
  54     .bmAttributes     = USB_ENDPOINT_XFER_BULK,
  55     .wMaxPacketSize   = 0,
  56     .bInterval        = 0
  57 };
  58
  59 #define BUFFER_SIZE 512 /* Max 16k because of controller limitations */
  60 #if CONFIG_CPU == IMX31L
  61 static unsigned char send_buffer[BUFFER_SIZE]
  62     USBDEVBSS_ATTR __attribute__((aligned(32)));
  63 static unsigned char receive_buffer[32]
  64     USBDEVBSS_ATTR __attribute__((aligned(32)));
  65 #else
  66 static unsigned char send_buffer[BUFFER_SIZE] __attribute__((aligned(32)));
  67 static unsigned char receive_buffer[32] __attribute__((aligned(32)));
  68 #endif
  69
  70 static bool busy_sending = false;
  71 static int buffer_start;
  72 static int buffer_length;
  73 static bool active = false;
  74
  75 static int ep_in, ep_out;
  76 static int usb_interface;
  77
  78 static struct mutex sendlock SHAREDBSS_ATTR;
  79
  80 static void sendout(void)
  81 {
  82     if(buffer_start+buffer_length > BUFFER_SIZE)
  83     {
  84         /* Buffer wraps. Only send the first part */
  85         usb_drv_send_nonblocking(ep_in, &send_buffer[buffer_start],
  86                                  (BUFFER_SIZE - buffer_start));
  87     }
  88     else
  89     {
  90         /* Send everything */
  91         usb_drv_send_nonblocking(ep_in, &send_buffer[buffer_start],
  92                                  buffer_length);
  93     }
  94     busy_sending=true;
  95 }
  96
  97 int usb_serial_request_endpoints(struct usb_class_driver *drv)
  98 {
  99     ep_in = usb_core_request_endpoint(USB_DIR_IN, drv);
 100
 101     if (ep_in < 0)
 102         return -1;
 103
 104     ep_out = usb_core_request_endpoint(USB_DIR_OUT, drv);
 105
 106     if (ep_out < 0) {
 107         usb_core_release_endpoint(ep_in);
 108         return -1;
 109     }
 110
 111     return 0;
 112 }
 113
 114 int usb_serial_set_first_interface(int interface)
 115 {
 116     usb_interface = interface;
 117     return interface + 1;
 118 }
 119
 120
 121 int usb_serial_get_config_descriptor(unsigned char *dest,int max_packet_size)
 122 {
 123     unsigned char *orig_dest = dest;
 124
 125     endpoint_descriptor.wMaxPacketSize=max_packet_size;
 126     interface_descriptor.bInterfaceNumber=usb_interface;
 127
 128     memcpy(dest,&interface_descriptor,sizeof(struct usb_interface_descriptor));
 129     dest+=sizeof(struct usb_interface_descriptor);
 130
 131     endpoint_descriptor.bEndpointAddress = ep_in;
 132     memcpy(dest,&endpoint_descriptor,sizeof(struct usb_endpoint_descriptor));
 133     dest+=sizeof(struct usb_endpoint_descriptor);
 134
 135     endpoint_descriptor.bEndpointAddress = ep_out;
 136     memcpy(dest,&endpoint_descriptor,sizeof(struct usb_endpoint_descriptor));
 137     dest+=sizeof(struct usb_endpoint_descriptor);
 138
 139     return (dest - orig_dest);
 140 }
 141
 142 void usb_serial_init_connection(void)
 143 {
 144     /* prime rx endpoint */
 145     usb_drv_recv(ep_out, receive_buffer, sizeof receive_buffer);
 146
 147     /* we come here too after a bus reset, so reset some data */
 148     mutex_lock(&sendlock);
 149     busy_sending = false;
 150     if(buffer_length>0)
 151     {
 152         sendout();
 153     }
 154     mutex_unlock(&sendlock);
 155 }
 156
 157 /* called by usb_code_init() */
 158 void usb_serial_init(void)
 159 {
 160     logf("serial: init");
 161     busy_sending = false;
 162     buffer_start = 0;
 163     buffer_length = 0;
 164     active = true;
 165     mutex_init(&sendlock);
 166 }
 167
 168 void usb_serial_disconnect(void)
 169 {
 170     active = false;
 171 }
 172
 173 void usb_serial_send(unsigned char *data,int length)
 174 {
 175     if(!active)
 176         return;
 177     if(length<=0)
 178         return;
 179     mutex_lock(&sendlock);
 180     if(buffer_start+buffer_length > BUFFER_SIZE)
 181     {
 182         /* current buffer wraps, so new data can't */
 183         int available_space = BUFFER_SIZE - buffer_length;
 184         length=MIN(length,available_space);
 185         memcpy(&send_buffer[(buffer_start+buffer_length)%BUFFER_SIZE],
 186                data,length);
 187         buffer_length+=length;
 188     }
 189     else
 190     {
 191         /* current buffer doesn't wrap, so new data might */
 192         int available_end_space = (BUFFER_SIZE - (buffer_start+buffer_length));
 193         int first_chunk = MIN(length,available_end_space);
 194         memcpy(&send_buffer[buffer_start + buffer_length],data,first_chunk);
 195         length-=first_chunk;
 196         buffer_length+=first_chunk;
 197         if(length>0)
 198         {
 199             /* wrap */
 200             memcpy(&send_buffer[0],&data[first_chunk],MIN(length,buffer_start));
 201             buffer_length+=MIN(length,buffer_start);
 202         }
 203     }
 204     if(busy_sending)
 205     {
 206         /* Do nothing. The transfer completion handler will pick it up */
 207     }
 208     else
 209     {
 210         sendout();
 211     }
 212     mutex_unlock(&sendlock);
 213 }
 214
 215 /* called by usb_core_transfer_complete() */
 216 void usb_serial_transfer_complete(int ep,int dir, int status, int length)
 217 {
 218     (void)ep;
 219     switch (dir) {
 220         case USB_DIR_OUT:
 221             logf("serial: %s", receive_buffer);
 222             /* Data received. TODO : Do something with it ? */
 223             usb_drv_recv(ep_out, receive_buffer, sizeof receive_buffer);
 224             break;
 225
 226         case USB_DIR_IN:
 227             mutex_lock(&sendlock);
 228             /* Data sent out. Update circular buffer */
 229             if(status == 0)
 230             {
 231                 buffer_start = (buffer_start + length)%BUFFER_SIZE;
 232                 buffer_length -= length;
 233             }
 234             busy_sending = false;
 235
 236             if(buffer_length>0)
 237             {
 238                 sendout();
 239             }
 240             mutex_unlock(&sendlock);
 241             break;
 242     }
 243 }
 244
 245 /* called by usb_core_control_request() */
 246 bool usb_serial_control_request(struct usb_ctrlrequest* req)
 247 {
 248     bool handled = false;
 249     switch (req->bRequest) {
 250         default:
 251             logf("serial: unhandeld req %d", req->bRequest);
 252     }
 253     return handled;
 254 }
 255
 256 #endif /*USB_SERIAL*/