src/class/cdc/cdc_host.c

/* 
 * The MIT License (MIT)
 *
 * Copyright (c) 2019 Ha Thach (tinyusb.org)
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * This file is part of the TinyUSB stack.
 */

#include "tusb_option.h"

#if (TUSB_OPT_HOST_ENABLED && CFG_TUH_CDC)

#include "common/tusb_common.h"
#include "cdc_host.h"

//--------------------------------------------------------------------+
// MACRO CONSTANT TYPEDEF
//--------------------------------------------------------------------+
typedef struct {
  uint8_t itf_num;
  uint8_t itf_protocol;

  uint8_t ep_notif;
  uint8_t ep_in;
  uint8_t ep_out;

  cdc_acm_capability_t acm_capability;

} cdch_data_t;

//--------------------------------------------------------------------+
// INTERNAL OBJECT & FUNCTION DECLARATION
//--------------------------------------------------------------------+
static cdch_data_t cdch_data[CFG_TUSB_HOST_DEVICE_MAX];

bool tuh_cdc_mounted(uint8_t dev_addr)
{
  cdch_data_t* cdc = &cdch_data[dev_addr-1];
  return cdc->ep_in && cdc->ep_out;
}

bool tuh_cdc_is_busy(uint8_t dev_addr, cdc_pipeid_t pipeid)
{
  if ( !tuh_cdc_mounted(dev_addr) ) return false;

  cdch_data_t const * p_cdc = &cdch_data[dev_addr-1];

  switch (pipeid)
  {
    case CDC_PIPE_NOTIFICATION:
      return hcd_edpt_busy(dev_addr, p_cdc->ep_notif );

    case CDC_PIPE_DATA_IN:
      return hcd_edpt_busy(dev_addr, p_cdc->ep_in );

    case CDC_PIPE_DATA_OUT:
      return hcd_edpt_busy(dev_addr, p_cdc->ep_out );

    default:
      return false;
  }
}

//--------------------------------------------------------------------+
// APPLICATION API (parameter validation needed)
//--------------------------------------------------------------------+
bool tuh_cdc_serial_is_mounted(uint8_t dev_addr)
{
  // TODO consider all AT Command as serial candidate
  return tuh_cdc_mounted(dev_addr)                                         &&
      (CDC_COMM_PROTOCOL_ATCOMMAND <= cdch_data[dev_addr-1].itf_protocol) &&
      (cdch_data[dev_addr-1].itf_protocol <= CDC_COMM_PROTOCOL_ATCOMMAND_CDMA);
}

bool tuh_cdc_send(uint8_t dev_addr, void const * p_data, uint32_t length, bool is_notify)
{
  TU_VERIFY( tuh_cdc_mounted(dev_addr) );
  TU_VERIFY( p_data != NULL && length, TUSB_ERROR_INVALID_PARA);

  uint8_t const ep_out = cdch_data[dev_addr-1].ep_out;
  if ( hcd_edpt_busy(dev_addr, ep_out) ) return false;

  return hcd_pipe_xfer(dev_addr, ep_out, (void *) p_data, length, is_notify);
}

bool tuh_cdc_receive(uint8_t dev_addr, void * p_buffer, uint32_t length, bool is_notify)
{
  TU_VERIFY( tuh_cdc_mounted(dev_addr) );
  TU_VERIFY( p_buffer != NULL && length, TUSB_ERROR_INVALID_PARA);

  uint8_t const ep_in = cdch_data[dev_addr-1].ep_in;
  if ( hcd_edpt_busy(dev_addr, ep_in) ) return false;

  return hcd_pipe_xfer(dev_addr, ep_in, p_buffer, length, is_notify);
}

//--------------------------------------------------------------------+
// USBH-CLASS DRIVER API
//--------------------------------------------------------------------+
void cdch_init(void)
{
  tu_memclr(cdch_data, sizeof(cdch_data_t)*CFG_TUSB_HOST_DEVICE_MAX);
}

bool cdch_open(uint8_t rhport, uint8_t dev_addr, tusb_desc_interface_t const *itf_desc, uint16_t *p_length)
{
  // Only support ACM
  TU_VERIFY( CDC_COMM_SUBCLASS_ABSTRACT_CONTROL_MODEL == itf_desc->bInterfaceSubClass);

  // Only support AT commands, no protocol and vendor specific commands.
  TU_VERIFY(tu_within(CDC_COMM_PROTOCOL_NONE, itf_desc->bInterfaceProtocol, CDC_COMM_PROTOCOL_ATCOMMAND_CDMA) ||
            0xff == itf_desc->bInterfaceProtocol);

  uint8_t const * p_desc;
  cdch_data_t * p_cdc;

  p_desc = tu_desc_next(itf_desc);
  p_cdc  = &cdch_data[dev_addr-1];

  p_cdc->itf_num   = itf_desc->bInterfaceNumber;
  p_cdc->itf_protocol = itf_desc->bInterfaceProtocol; // TODO 0xff is consider as rndis candidate, other is virtual Com

  //------------- Communication Interface -------------//
  (*p_length) = sizeof(tusb_desc_interface_t);

  // Communication Functional Descriptors
  while( TUSB_DESC_CS_INTERFACE == p_desc[DESC_OFFSET_TYPE] )
  {
    if ( CDC_FUNC_DESC_ABSTRACT_CONTROL_MANAGEMENT == cdc_functional_desc_typeof(p_desc) )
    {
      // save ACM bmCapabilities
      p_cdc->acm_capability = ((cdc_desc_func_acm_t const *) p_desc)->bmCapabilities;
    }

    (*p_length) += p_desc[DESC_OFFSET_LEN];
    p_desc = tu_desc_next(p_desc);
  }

  if ( TUSB_DESC_ENDPOINT == p_desc[DESC_OFFSET_TYPE])
  {
    // notification endpoint
    tusb_desc_endpoint_t const * ep_desc = (tusb_desc_endpoint_t const *) p_desc;

    TU_ASSERT( hcd_edpt_open(rhport, dev_addr, ep_desc) );
    p_cdc->ep_notif = ep_desc->bEndpointAddress;

    (*p_length) += p_desc[DESC_OFFSET_LEN];
    p_desc = tu_desc_next(p_desc);
  }

  //------------- Data Interface (if any) -------------//
  if ( (TUSB_DESC_INTERFACE == p_desc[DESC_OFFSET_TYPE]) &&
       (TUSB_CLASS_CDC_DATA == ((tusb_desc_interface_t const *) p_desc)->bInterfaceClass) )
  {
    (*p_length) += p_desc[DESC_OFFSET_LEN];
    p_desc = tu_desc_next(p_desc);

    // data endpoints expected to be in pairs
    for(uint32_t i=0; i<2; i++)
    {
      tusb_desc_endpoint_t const *ep_desc = (tusb_desc_endpoint_t const *) p_desc;
      TU_ASSERT(TUSB_DESC_ENDPOINT == ep_desc->bDescriptorType);
      TU_ASSERT(TUSB_XFER_BULK == ep_desc->bmAttributes.xfer);

      TU_ASSERT(hcd_edpt_open(rhport, dev_addr, ep_desc));

      if ( tu_edpt_dir(ep_desc->bEndpointAddress) ==  TUSB_DIR_IN )
      {
        p_cdc->ep_in = ep_desc->bEndpointAddress;
      }else
      {
        p_cdc->ep_out = ep_desc->bEndpointAddress;
      }

      (*p_length) += p_desc[DESC_OFFSET_LEN];
      p_desc = tu_desc_next( p_desc );
    }
  }

  // FIXME move to seperate API : connect
  tusb_control_request_t request =
  {
    .bmRequestType_bit = { .recipient = TUSB_REQ_RCPT_INTERFACE, .type = TUSB_REQ_TYPE_CLASS, .direction = TUSB_DIR_OUT },
    .bRequest = CDC_REQUEST_SET_CONTROL_LINE_STATE,
    .wValue = 0x03, // dtr on, cst on
    .wIndex = p_cdc->itf_num,
    .wLength = 0
  };

  TU_ASSERT( usbh_control_xfer(dev_addr, &request, NULL) );

  return true;
}

void cdch_isr(uint8_t dev_addr, uint8_t ep_addr, xfer_result_t event, uint32_t xferred_bytes)
{
  (void) ep_addr;
  tuh_cdc_xfer_isr( dev_addr, event, 0, xferred_bytes );
}

void cdch_close(uint8_t dev_addr)
{
  cdch_data_t * p_cdc = &cdch_data[dev_addr-1];
  tu_memclr(p_cdc, sizeof(cdch_data_t));
}

#endif