usb-core.c

#include "usb-core.h"
#include "usb.h"
#include "usb-arch.h"
#include "usb-api.h"
#include "sys/process.h"
#include "descriptors.h"
#include "string-descriptors.h"

#include <stdio.h>

#ifdef DEBUG
#define PRINTF(...) printf(__VA_ARGS__)
#else
#define PRINTF(...)
#endif


struct USB_request_st usb_setup_buffer;
static USBBuffer ctrl_buffer;

#define SETUP_ID 1
#define OUT_ID 2
#define IN_ID 3
#define STATUS_OUT_ID 4
#define STATUS_IN_ID 5

static uint16_t usb_device_status;
static uint8_t usb_configuration_value;

static struct USBRequestHandlerHook *usb_request_handler_hooks = NULL;

static const unsigned char zero_byte = 0;
static const unsigned short zero_word = 0;

static unsigned char usb_flags = 0;
#define USB_FLAG_ADDRESS_PENDING 0x01

static struct process *global_user_event_pocess = NULL;
static unsigned int global_user_events = 0;

void
usb_set_global_event_process(struct process *p)
{
  global_user_event_pocess = p;
}
unsigned int
usb_get_global_events(void)
{
  unsigned int e = global_user_events;
  global_user_events = 0;
  return e;
}

static void
notify_user(unsigned int e)
{
  global_user_events |= e;
  if(global_user_event_pocess) {
    process_poll(global_user_event_pocess);
  }
}

void
usb_send_ctrl_response(const uint8_t * data, unsigned int len)
{
  if(ctrl_buffer.flags & USB_BUFFER_SUBMITTED)
    return;
  if(len >= usb_setup_buffer.wLength) {
    len = usb_setup_buffer.wLength;     /* Truncate if too long */
  }
  ctrl_buffer.flags = USB_BUFFER_NOTIFY | USB_BUFFER_IN;
  if(len < usb_setup_buffer.wLength) {
    ctrl_buffer.flags |= USB_BUFFER_SHORT_END;
  }
  ctrl_buffer.next = NULL;
  ctrl_buffer.data = (uint8_t *) data;
  ctrl_buffer.left = len;
  ctrl_buffer.id = IN_ID;
  usb_submit_xmit_buffer(0, &ctrl_buffer);
}

static uint8_t error_stall = 0;

void
usb_error_stall()
{
  error_stall = 1;
  usb_arch_control_stall(0);
}

void
usb_send_ctrl_status()
{
  if(ctrl_buffer.flags & USB_BUFFER_SUBMITTED)
    return;
  ctrl_buffer.flags = USB_BUFFER_NOTIFY | USB_BUFFER_IN;
  ctrl_buffer.next = NULL;
  ctrl_buffer.data = NULL;
  ctrl_buffer.left = 0;
  ctrl_buffer.id = STATUS_IN_ID;
  usb_submit_xmit_buffer(0, &ctrl_buffer);
}

static usb_ctrl_data_callback data_callback = NULL;

static uint8_t *ctrl_data = NULL;

static unsigned int ctrl_data_len = 0;

void
usb_get_ctrl_data(uint8_t * data, unsigned int length,
                  usb_ctrl_data_callback cb)
{
  if(ctrl_buffer.flags & USB_BUFFER_SUBMITTED)
    return;
  PRINTF("usb_get_ctrl_data: %d\n", length);
  data_callback = cb;
  ctrl_data = data;
  ctrl_data_len = length;
  ctrl_buffer.flags = USB_BUFFER_NOTIFY;
  ctrl_buffer.next = NULL;
  ctrl_buffer.data = data;
  ctrl_buffer.left = length;
  ctrl_buffer.id = OUT_ID;
  usb_submit_recv_buffer(0, &ctrl_buffer);
}

#if 0

void
usb_set_user_process(struct process *p)
{
  user_process = p;
}
#endif

static void
get_device_descriptor()
{
  usb_send_ctrl_response((unsigned char *)&device_descriptor,
                         sizeof(device_descriptor));
}

static void
get_string_descriptor()
{
#if OLD_STRING_DESCR
  if(LOW_BYTE(usb_setup_buffer.wValue) == 0) {
    usb_send_ctrl_response((const unsigned char *)string_languages->
                           lang_descr, string_languages->lang_descr->bLength);
  } else {
    const struct usb_st_string_descriptor *descriptor;

    unsigned char l;

    const struct usb_st_string_descriptor *const *table;

    const struct usb_st_string_language_map *map;

    if(LOW_BYTE(usb_setup_buffer.wValue) > string_languages->max_index) {
      usb_error_stall();
      return;
    }
    l = string_languages->num_lang;
    map = string_languages->map;
    table = map->descriptors;   /* Use first table if language not found */
    while(l > 0) {
      if(map->lang_id == usb_setup_buffer.wIndex) {
        table = map->descriptors;
        break;
      }
      map++;
      l--;
    }
    PRINTF("Lang id %04x = table %p\n", usb_setup_buffer.wIndex,
           (void *)table);
    descriptor = table[LOW_BYTE(usb_setup_buffer.wValue) - 1];
    usb_send_ctrl_response((const unsigned char *)descriptor,
                           descriptor->bLength);
  }
#else
  const struct usb_st_string_descriptor *descriptor;

  descriptor = (struct usb_st_string_descriptor *)
    usb_class_get_string_descriptor(usb_setup_buffer.wIndex,
                                    LOW_BYTE(usb_setup_buffer.wValue));
  if(!descriptor) {
    usb_error_stall();
    return;
  }
  usb_send_ctrl_response((const unsigned char *)descriptor,
                         descriptor->bLength);
#endif
}

static void
get_configuration_descriptor()
{
  usb_send_ctrl_response((unsigned char *)configuration_head,
                         configuration_head->wTotalLength);
}

static void
get_configuration()
{
  usb_send_ctrl_response((unsigned char *)&usb_configuration_value,
                         sizeof(usb_configuration_value));
}

/* Returns true if the configuration value changed */
static int
set_configuration()
{
  notify_user(USB_EVENT_CONFIG);
  if(usb_configuration_value != LOW_BYTE(usb_setup_buffer.wValue)) {
    usb_configuration_value = LOW_BYTE(usb_setup_buffer.wValue);
    usb_arch_set_configuration(usb_configuration_value);
    usb_send_ctrl_status();
    return 1;
  } else {
    usb_send_ctrl_status();
    return 0;
  }
}

static void
get_device_status()
{
  PRINTF("get_device_status\n");
  usb_send_ctrl_response((const unsigned char *)&usb_device_status,
                         sizeof(usb_device_status));
}

static void
get_endpoint_status()
{
  static uint16_t status;

  PRINTF("get_endpoint_status\n");
  if((usb_setup_buffer.wIndex & 0x7f) == 0) {
    usb_send_ctrl_response((const unsigned char *)&zero_word,
                           sizeof(zero_word));
  } else {
    status = usb_arch_get_ep_status(usb_setup_buffer.wIndex);
    usb_send_ctrl_response((uint8_t *) & status, sizeof(status));
  }
}

static void
get_interface_status()
{
  PRINTF("get_interface_status\n");
  usb_send_ctrl_response((const unsigned char *)&zero_word,
                         sizeof(zero_word));
}

static void
get_interface()
{
  PRINTF("get_interface\n");
  if(usb_configuration_value == 0)
    usb_error_stall();
  else {
    usb_send_ctrl_response(&zero_byte, sizeof(zero_byte));
  }
}


static unsigned int
handle_standard_requests()
{
  switch (usb_setup_buffer.bmRequestType) {
  case 0x80:                   /* standard device IN requests */
    switch (usb_setup_buffer.bRequest) {
    case GET_DESCRIPTOR:
      switch (HIGH_BYTE(usb_setup_buffer.wValue)) {
      case DEVICE:
        get_device_descriptor();
        break;
      case CONFIGURATION:
        get_configuration_descriptor();
        break;
      case STRING:
        get_string_descriptor();
        break;
      default:
        /* Unknown descriptor */
        return 0;
      }
      break;
    case GET_CONFIGURATION:
      get_configuration();
      break;
    case GET_STATUS:
      get_device_status();
      break;
    case GET_INTERFACE:
      get_interface();
      break;
    default:
      return 0;
    }
    break;
  case 0x81:                   /* standard interface IN requests */
    switch (usb_setup_buffer.bRequest) {
    case GET_STATUS:
      get_interface_status();
      break;
#ifdef HID_ENABLED
    case GET_DESCRIPTOR:
      switch (USB_setup_buffer.wValue.byte.high) {
      case REPORT:
        get_report_descriptor();
        break;
      }
      break;
#endif
    default:
      return 0;
    }
    break;
  case 0x82:                   /* standard endpoint IN requests */
    switch (usb_setup_buffer.bRequest) {
    case GET_STATUS:
      get_endpoint_status();
      break;
    default:
      return 0;
    }
    break;
  case 0x00:                   /* standard device OUT requests */
    switch (usb_setup_buffer.bRequest) {
    case SET_ADDRESS:
      PRINTF("Address: %d\n", LOW_BYTE(usb_setup_buffer.wValue));
      usb_flags |= USB_FLAG_ADDRESS_PENDING;
      /* The actual setting of the address is done when the status packet
         is sent. */
      usb_send_ctrl_status();
      break;
#if SETABLE_STRING_DESCRIPTORS > 0
    case SET_DESCRIPTOR:
      if(usb_setup_buffer.wValue.byte.high == STRING) {
        set_string_descriptor();
      } else {
        return 0;
      }
      break;
#endif
    case SET_CONFIGURATION:
      if(set_configuration()) {
#if 0
        config_msg.data.config = LOW_BYTE(usb_setup_buffer.wValue);
        notify_user(&config_msg);
#endif
      }
      break;
    default:
      return 0;
    }
    break;
  case 0x01:                   /* standard interface OUT requests */
    switch (usb_setup_buffer.bRequest) {
    case SET_INTERFACE:
      /* Change interface here if we support more than one */
      usb_send_ctrl_status();
      break;
    default:
      return 0;
    }
    break;
  case 0x02:                   /* standard endpoint OUT requests */
    switch (usb_setup_buffer.bRequest) {
    case SET_FEATURE:
    case CLEAR_FEATURE:
      if(usb_setup_buffer.wValue == ENDPOINT_HALT_FEATURE) {
        usb_arch_halt_endpoint(usb_setup_buffer.wIndex,
                               usb_setup_buffer.bRequest == SET_FEATURE);
        usb_send_ctrl_status();
      } else {
        usb_error_stall();
      }
      break;
    default:
      return 0;
    }
    break;
#ifdef HID_ENABLED
  case 0xa1:                   /* class specific interface IN request */
    switch (USB_setup_buffer.bRequest) {
    case GET_HID_REPORT:
      PRINTF("Get report\n");
      send_ctrl_response((code u_int8_t *) & zero_byte, sizeof(zero_byte));
      break;
    case GET_HID_IDLE:
      PRINTF("Get idle\n");
      send_ctrl_response((code u_int8_t *) & zero_byte, sizeof(zero_byte));
      break;
    default:
      return 0;
    }
    break;
  case 0x21:                   /* class specific interface OUT request */
    switch (USB_setup_buffer.bRequest) {
    case SET_HID_IDLE:
      PRINTF("Set idle\n");
      send_ctrl_status();
      break;
    default:
      return 0;
    }
    break;
#endif
  default:
    return 0;
  }
  return 1;
}

static const struct USBRequestHandler standard_request_handler = {
  0x00,
  0x60,
  0x00,
  0x00,
  handle_standard_requests
};

static struct USBRequestHandlerHook standard_request_hook = {
  NULL,
  &standard_request_handler
};

static void
submit_setup(void)
{
  ctrl_buffer.next = NULL;
  ctrl_buffer.data = (uint8_t *) & usb_setup_buffer;
  ctrl_buffer.left = sizeof(usb_setup_buffer);
  ctrl_buffer.flags = (USB_BUFFER_PACKET_END | USB_BUFFER_SETUP
                       | USB_BUFFER_NOTIFY);
  ctrl_buffer.id = SETUP_ID;
  usb_submit_recv_buffer(0, &ctrl_buffer);
}

PROCESS(usb_process, "USB");

PROCESS_THREAD(usb_process, ev, data)
{
  PROCESS_BEGIN();
  PRINTF("USB process started\n");
  while(1) {
    PROCESS_WAIT_EVENT();
    if(ev == PROCESS_EVENT_EXIT)
      break;
    if(ev == PROCESS_EVENT_POLL) {
      unsigned int events = usb_arch_get_global_events();

      if(events) {
        if(events & USB_EVENT_RESET) {
          submit_setup();
          usb_configuration_value = 0;
          notify_user(USB_EVENT_RESET);
        }
        if(events & USB_EVENT_SUSPEND) {
          notify_user(USB_EVENT_SUSPEND);
        }
        if(events & USB_EVENT_RESUME) {
          notify_user(USB_EVENT_RESUME);
        }

      }
      events = usb_get_ep_events(0);
      if(events) {
        if((events & USB_EP_EVENT_NOTIFICATION)
           && !(ctrl_buffer.flags & USB_BUFFER_SUBMITTED)) {
          /* PRINTF("Endpoint 0\n"); */
          if(ctrl_buffer.flags & USB_BUFFER_FAILED) {
            /* Something went wrong with the buffer, just wait for a
               new SETUP packet */
            PRINTF("Discarded\n");
            submit_setup();
          } else if(ctrl_buffer.flags & USB_BUFFER_SETUP) {
            struct USBRequestHandlerHook *hook = usb_request_handler_hooks;

            PRINTF("Setup\n");
            {
              unsigned int i;

              for(i = 0; i < 8; i++)
                PRINTF(" %02x", ((unsigned char *)&usb_setup_buffer)[i]);
              PRINTF("\n");
            }

            while(hook) {
              const struct USBRequestHandler *handler = hook->handler;

              /* Check if the handler matches the request */
              if(((handler->request_type ^ usb_setup_buffer.bmRequestType)
                  & handler->request_type_mask) == 0
                 && ((handler->request ^ usb_setup_buffer.bRequest)
                     & handler->request_mask) == 0) {
                if(handler->handler_func())
                  break;
              }
              hook = hook->next;
            }
            if(!hook) {
              /* No handler found */
              usb_error_stall();
              PRINTF("Unhandled setup: %02x %02x %04x %04x %04x\n",
                     usb_setup_buffer.bmRequestType,
                     usb_setup_buffer.bRequest, usb_setup_buffer.wValue,
                     usb_setup_buffer.wIndex, usb_setup_buffer.wLength);
            }
            /* Check if any handler stalled the pipe, if so prepare for
               next setup */
            if(error_stall) {
              error_stall = 0;
              submit_setup();
            }
          } else {
            if(ctrl_buffer.id == IN_ID) {
              /* Receive status stage */
              PRINTF("Status OUT\n");
              ctrl_buffer.flags = USB_BUFFER_NOTIFY;
              ctrl_buffer.next = NULL;
              ctrl_buffer.data = NULL;
              ctrl_buffer.left = 0;
              ctrl_buffer.id = STATUS_OUT_ID;
              usb_submit_recv_buffer(0, &ctrl_buffer);
            } else if(ctrl_buffer.id == STATUS_OUT_ID) {
              PRINTF("Status OUT done\n");
              submit_setup();
            } else if(ctrl_buffer.id == STATUS_IN_ID) {
              PRINTF("Status IN done\n");
              if(usb_flags & USB_FLAG_ADDRESS_PENDING) {
                while(usb_send_pending(0));
                usb_arch_set_address(LOW_BYTE(usb_setup_buffer.wValue));
                usb_flags &= ~USB_FLAG_ADDRESS_PENDING;
              }
              submit_setup();
            } else if(ctrl_buffer.id == OUT_ID) {
              PRINTF("OUT\n");
              if(data_callback) {
                data_callback(ctrl_data, ctrl_data_len - ctrl_buffer.left);
              } else {
                usb_send_ctrl_status();
              }
            }
          }
        }
      }
    }
  }
  PROCESS_END();
}


void
usb_setup(void)
{
  usb_arch_setup();
  process_start(&usb_process, NULL);
  usb_arch_set_global_event_process(&usb_process);
  usb_set_ep_event_process(0, &usb_process);

  usb_register_request_handler(&standard_request_hook);
}

void
usb_register_request_handler(struct USBRequestHandlerHook *hook)
{
  struct USBRequestHandlerHook **prevp = &usb_request_handler_hooks;
  /* Find last hook */
  while(*prevp) {
    prevp = &(*prevp)->next;
  }
  /* Add last */
  *prevp = hook;
  hook->next = NULL;
}

void
usb_prepend_request_handler(struct USBRequestHandlerHook *hook)
{
  hook->next = usb_request_handler_hooks;
  usb_request_handler_hooks = hook;
}


unsigned int
usb_get_current_configuration(void)
{
  return usb_configuration_value;
}

void
usb_setup_bulk_endpoint(unsigned char addr)
{
  usb_arch_setup_bulk_endpoint(addr);
}

void
usb_setup_interrupt_endpoint(unsigned char addr)
{
  usb_arch_setup_interrupt_endpoint(addr);
}

void
usb_disable_endpoint(uint8_t addr)
{
  usb_arch_discard_all_buffers(addr);
  usb_arch_disable_endpoint(addr);
}

void
usb_discard_all_buffers(uint8_t addr)
{
  usb_arch_discard_all_buffers(addr);
}

void
usb_halt_endpoint(uint8_t addr, int halt)
{
  usb_arch_halt_endpoint(addr, halt);
}

int
usb_send_pending(uint8_t addr)
{
  return usb_arch_send_pending(addr);
}