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path: root/demos/ARMCM4-STM32F407-LWIP-FATFS-USB/main.c
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/*
    ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
                 2011,2012 Giovanni Di Sirio.

    This file is part of ChibiOS/RT.

    ChibiOS/RT is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.

    ChibiOS/RT is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include <stdio.h>
#include <string.h>

#include "ch.h"
#include "hal.h"
#include "test.h"

#include "usb_cdc.h"
#include "chprintf.h"
#include "shell.h"

#include "lwipthread.h"
#include "web/web.h"

#include "ff.h"

/*===========================================================================*/
/* Card insertion monitor.                                                   */
/*===========================================================================*/

#define POLLING_INTERVAL                10
#define POLLING_DELAY                   10

/**
 * @brief   Card monitor timer.
 */
static VirtualTimer tmr;

/**
 * @brief   Debounce counter.
 */
static unsigned cnt;

/**
 * @brief   Card event sources.
 */
static EventSource inserted_event, removed_event;

/**
 * @brief   Insertion monitor timer callback function.
 *
 * @param[in] p         pointer to the @p BaseBlockDevice object
 *
 * @notapi
 */
static void tmrfunc(void *p) {
  BaseBlockDevice *bbdp = p;

  chSysLockFromIsr();
  if (cnt > 0) {
    if (blkIsInserted(bbdp)) {
      if (--cnt == 0) {
        chEvtBroadcastI(&inserted_event);
      }
    }
    else
      cnt = POLLING_INTERVAL;
  }
  else {
    if (!blkIsInserted(bbdp)) {
      cnt = POLLING_INTERVAL;
      chEvtBroadcastI(&removed_event);
    }
  }
  chVTSetI(&tmr, MS2ST(POLLING_DELAY), tmrfunc, bbdp);
  chSysUnlockFromIsr();
}

/**
 * @brief   Polling monitor start.
 *
 * @param[in] p         pointer to an object implementing @p BaseBlockDevice
 *
 * @notapi
 */
static void tmr_init(void *p) {

  chEvtInit(&inserted_event);
  chEvtInit(&removed_event);
  chSysLock();
  cnt = POLLING_INTERVAL;
  chVTSetI(&tmr, MS2ST(POLLING_DELAY), tmrfunc, p);
  chSysUnlock();
}

/*===========================================================================*/
/* FatFs related.                                                            */
/*===========================================================================*/

/**
 * @brief FS object.
 */
static FATFS SDC_FS;

/* FS mounted and ready.*/
static bool_t fs_ready = FALSE;

/* Generic large buffer.*/
static uint8_t fbuff[1024];

static FRESULT scan_files(BaseSequentialStream *chp, char *path) {
  FRESULT res;
  FILINFO fno;
  DIR dir;
  int i;
  char *fn;

  res = f_opendir(&dir, path);
  if (res == FR_OK) {
    i = strlen(path);
    for (;;) {
      res = f_readdir(&dir, &fno);
      if (res != FR_OK || fno.fname[0] == 0)
        break;
      if (fno.fname[0] == '.')
        continue;
      fn = fno.fname;
      if (fno.fattrib & AM_DIR) {
        path[i++] = '/';
        strcpy(&path[i], fn);
        res = scan_files(chp, path);
        if (res != FR_OK)
          break;
        path[i] = 0;
      }
      else {
        chprintf(chp, "%s/%s\r\n", path, fn);
      }
    }
  }
  return res;
}

/*===========================================================================*/
/* USB related stuff.                                                        */
/*===========================================================================*/

/*
 * USB Driver structure.
 */
static SerialUSBDriver SDU1;

/*
 * USB Device Descriptor.
 */
static const uint8_t vcom_device_descriptor_data[18] = {
  USB_DESC_DEVICE       (0x0110,        /* bcdUSB (1.1).                    */
                         0x02,          /* bDeviceClass (CDC).              */
                         0x00,          /* bDeviceSubClass.                 */
                         0x00,          /* bDeviceProtocol.                 */
                         0x40,          /* bMaxPacketSize.                  */
                         0x0483,        /* idVendor (ST).                   */
                         0x5740,        /* idProduct.                       */
                         0x0200,        /* bcdDevice.                       */
                         1,             /* iManufacturer.                   */
                         2,             /* iProduct.                        */
                         3,             /* iSerialNumber.                   */
                         1)             /* bNumConfigurations.              */
};

/*
 * Device Descriptor wrapper.
 */
static const USBDescriptor vcom_device_descriptor = {
  sizeof vcom_device_descriptor_data,
  vcom_device_descriptor_data
};

/* Configuration Descriptor tree for a CDC.*/
static const uint8_t vcom_configuration_descriptor_data[67] = {
  /* Configuration Descriptor.*/
  USB_DESC_CONFIGURATION(67,            /* wTotalLength.                    */
                         0x02,          /* bNumInterfaces.                  */
                         0x01,          /* bConfigurationValue.             */
                         0,             /* iConfiguration.                  */
                         0xC0,          /* bmAttributes (self powered).     */
                         50),           /* bMaxPower (100mA).               */
  /* Interface Descriptor.*/
  USB_DESC_INTERFACE    (0x00,          /* bInterfaceNumber.                */
                         0x00,          /* bAlternateSetting.               */
                         0x01,          /* bNumEndpoints.                   */
                         0x02,          /* bInterfaceClass (Communications
                                           Interface Class, CDC section
                                           4.2).                            */
                         0x02,          /* bInterfaceSubClass (Abstract
                                         Control Model, CDC section 4.3).   */
                         0x01,          /* bInterfaceProtocol (AT commands,
                                           CDC section 4.4).                */
                         0),            /* iInterface.                      */
  /* Header Functional Descriptor (CDC section 5.2.3).*/
  USB_DESC_BYTE         (5),            /* bLength.                         */
  USB_DESC_BYTE         (0x24),         /* bDescriptorType (CS_INTERFACE).  */
  USB_DESC_BYTE         (0x00),         /* bDescriptorSubtype (Header
                                           Functional Descriptor.           */
  USB_DESC_BCD          (0x0110),       /* bcdCDC.                          */
  /* Call Management Functional Descriptor. */
  USB_DESC_BYTE         (5),            /* bFunctionLength.                 */
  USB_DESC_BYTE         (0x24),         /* bDescriptorType (CS_INTERFACE).  */
  USB_DESC_BYTE         (0x01),         /* bDescriptorSubtype (Call Management
                                           Functional Descriptor).          */
  USB_DESC_BYTE         (0x00),         /* bmCapabilities (D0+D1).          */
  USB_DESC_BYTE         (0x01),         /* bDataInterface.                  */
  /* ACM Functional Descriptor.*/
  USB_DESC_BYTE         (4),            /* bFunctionLength.                 */
  USB_DESC_BYTE         (0x24),         /* bDescriptorType (CS_INTERFACE).  */
  USB_DESC_BYTE         (0x02),         /* bDescriptorSubtype (Abstract
                                           Control Management Descriptor).  */
  USB_DESC_BYTE         (0x02),         /* bmCapabilities.                  */
  /* Union Functional Descriptor.*/
  USB_DESC_BYTE         (5),            /* bFunctionLength.                 */
  USB_DESC_BYTE         (0x24),         /* bDescriptorType (CS_INTERFACE).  */
  USB_DESC_BYTE         (0x06),         /* bDescriptorSubtype (Union
                                           Functional Descriptor).          */
  USB_DESC_BYTE         (0x00),         /* bMasterInterface (Communication
                                           Class Interface).                */
  USB_DESC_BYTE         (0x01),         /* bSlaveInterface0 (Data Class
                                           Interface).                      */
  /* Endpoint 2 Descriptor.*/
  USB_DESC_ENDPOINT     (USB_CDC_INTERRUPT_REQUEST_EP|0x80,
                         0x03,          /* bmAttributes (Interrupt).        */
                         0x0008,        /* wMaxPacketSize.                  */
                         0xFF),         /* bInterval.                       */
  /* Interface Descriptor.*/
  USB_DESC_INTERFACE    (0x01,          /* bInterfaceNumber.                */
                         0x00,          /* bAlternateSetting.               */
                         0x02,          /* bNumEndpoints.                   */
                         0x0A,          /* bInterfaceClass (Data Class
                                           Interface, CDC section 4.5).     */
                         0x00,          /* bInterfaceSubClass (CDC section
                                           4.6).                            */
                         0x00,          /* bInterfaceProtocol (CDC section
                                           4.7).                            */
                         0x00),         /* iInterface.                      */
  /* Endpoint 3 Descriptor.*/
  USB_DESC_ENDPOINT     (USB_CDC_DATA_AVAILABLE_EP,     /* bEndpointAddress.*/
                         0x02,          /* bmAttributes (Bulk).             */
                         0x0040,        /* wMaxPacketSize.                  */
                         0x00),         /* bInterval.                       */
  /* Endpoint 1 Descriptor.*/
  USB_DESC_ENDPOINT     (USB_CDC_DATA_REQUEST_EP|0x80,  /* bEndpointAddress.*/
                         0x02,          /* bmAttributes (Bulk).             */
                         0x0040,        /* wMaxPacketSize.                  */
                         0x00)          /* bInterval.                       */
};

/*
 * Configuration Descriptor wrapper.
 */
static const USBDescriptor vcom_configuration_descriptor = {
  sizeof vcom_configuration_descriptor_data,
  vcom_configuration_descriptor_data
};

/*
 * U.S. English language identifier.
 */
static const uint8_t vcom_string0[] = {
  USB_DESC_BYTE(4),                     /* bLength.                         */
  USB_DESC_BYTE(USB_DESCRIPTOR_STRING), /* bDescriptorType.                 */
  USB_DESC_WORD(0x0409)                 /* wLANGID (U.S. English).          */
};

/*
 * Vendor string.
 */
static const uint8_t vcom_string1[] = {
  USB_DESC_BYTE(38),                    /* bLength.                         */
  USB_DESC_BYTE(USB_DESCRIPTOR_STRING), /* bDescriptorType.                 */
  'S', 0, 'T', 0, 'M', 0, 'i', 0, 'c', 0, 'r', 0, 'o', 0, 'e', 0,
  'l', 0, 'e', 0, 'c', 0, 't', 0, 'r', 0, 'o', 0, 'n', 0, 'i', 0,
  'c', 0, 's', 0
};

/*
 * Device Description string.
 */
static const uint8_t vcom_string2[] = {
  USB_DESC_BYTE(56),                    /* bLength.                         */
  USB_DESC_BYTE(USB_DESCRIPTOR_STRING), /* bDescriptorType.                 */
  'C', 0, 'h', 0, 'i', 0, 'b', 0, 'i', 0, 'O', 0, 'S', 0, '/', 0,
  'R', 0, 'T', 0, ' ', 0, 'V', 0, 'i', 0, 'r', 0, 't', 0, 'u', 0,
  'a', 0, 'l', 0, ' ', 0, 'C', 0, 'O', 0, 'M', 0, ' ', 0, 'P', 0,
  'o', 0, 'r', 0, 't', 0
};

/*
 * Serial Number string.
 */
static const uint8_t vcom_string3[] = {
  USB_DESC_BYTE(8),                     /* bLength.                         */
  USB_DESC_BYTE(USB_DESCRIPTOR_STRING), /* bDescriptorType.                 */
  '0' + CH_KERNEL_MAJOR, 0,
  '0' + CH_KERNEL_MINOR, 0,
  '0' + CH_KERNEL_PATCH, 0
};

/*
 * Strings wrappers array.
 */
static const USBDescriptor vcom_strings[] = {
  {sizeof vcom_string0, vcom_string0},
  {sizeof vcom_string1, vcom_string1},
  {sizeof vcom_string2, vcom_string2},
  {sizeof vcom_string3, vcom_string3}
};

/*
 * Handles the GET_DESCRIPTOR callback. All required descriptors must be
 * handled here.
 */
static const USBDescriptor *get_descriptor(USBDriver *usbp,
                                           uint8_t dtype,
                                           uint8_t dindex,
                                           uint16_t lang) {

  (void)usbp;
  (void)lang;
  switch (dtype) {
  case USB_DESCRIPTOR_DEVICE:
    return &vcom_device_descriptor;
  case USB_DESCRIPTOR_CONFIGURATION:
    return &vcom_configuration_descriptor;
  case USB_DESCRIPTOR_STRING:
    if (dindex < 4)
      return &vcom_strings[dindex];
  }
  return NULL;
}

/**
 * @brief   IN EP1 state.
 */
static USBInEndpointState ep1instate;

/**
 * @brief   EP1 initialization structure (IN only).
 */
static const USBEndpointConfig ep1config = {
  USB_EP_MODE_TYPE_BULK,
  NULL,
  sduDataTransmitted,
  NULL,
  0x0040,
  0x0000,
  &ep1instate,
  NULL,
  NULL
};

/**
 * @brief   OUT EP2 state.
 */
USBOutEndpointState ep2outstate;

/**
 * @brief   EP2 initialization structure (IN only).
 */
static const USBEndpointConfig ep2config = {
  USB_EP_MODE_TYPE_INTR,
  NULL,
  sduInterruptTransmitted,
  NULL,
  0x0010,
  0x0000,
  NULL,
  &ep2outstate,
  NULL
};

/**
 * @brief   OUT EP2 state.
 */
USBOutEndpointState ep3outstate;

/**
 * @brief   EP3 initialization structure (OUT only).
 */
static const USBEndpointConfig ep3config = {
  USB_EP_MODE_TYPE_BULK,
  NULL,
  NULL,
  sduDataReceived,
  0x0000,
  0x0040,
  NULL,
  &ep3outstate,
  NULL
};

/*
 * Handles the USB driver global events.
 */
static void usb_event(USBDriver *usbp, usbevent_t event) {

  switch (event) {
  case USB_EVENT_RESET:
    return;
  case USB_EVENT_ADDRESS:
    return;
  case USB_EVENT_CONFIGURED:
    chSysLockFromIsr();

    /* Enables the endpoints specified into the configuration.
       Note, this callback is invoked from an ISR so I-Class functions
       must be used.*/
    usbInitEndpointI(usbp, USB_CDC_DATA_REQUEST_EP, &ep1config);
    usbInitEndpointI(usbp, USB_CDC_INTERRUPT_REQUEST_EP, &ep2config);
    usbInitEndpointI(usbp, USB_CDC_DATA_AVAILABLE_EP, &ep3config);

    /* Resetting the state of the CDC subsystem.*/
    sduConfigureHookI(usbp);

    chSysUnlockFromIsr();
    return;
  case USB_EVENT_SUSPEND:
    return;
  case USB_EVENT_WAKEUP:
    return;
  case USB_EVENT_STALLED:
    return;
  }
  return;
}

/*
 * Serial over USB driver configuration.
 */
static const SerialUSBConfig serusbcfg = {
  &USBD1,
  {
    usb_event,
    get_descriptor,
    sduRequestsHook,
    NULL
  }
};

/*===========================================================================*/
/* Command line related.                                                     */
/*===========================================================================*/

#define SHELL_WA_SIZE   THD_WA_SIZE(2048)
#define TEST_WA_SIZE    THD_WA_SIZE(256)

static void cmd_mem(BaseSequentialStream *chp, int argc, char *argv[]) {
  size_t n, size;

  (void)argv;
  if (argc > 0) {
    chprintf(chp, "Usage: mem\r\n");
    return;
  }
  n = chHeapStatus(NULL, &size);
  chprintf(chp, "core free memory : %u bytes\r\n", chCoreStatus());
  chprintf(chp, "heap fragments   : %u\r\n", n);
  chprintf(chp, "heap free total  : %u bytes\r\n", size);
}

static void cmd_threads(BaseSequentialStream *chp, int argc, char *argv[]) {
  static const char *states[] = {THD_STATE_NAMES};
  Thread *tp;

  (void)argv;
  if (argc > 0) {
    chprintf(chp, "Usage: threads\r\n");
    return;
  }
  chprintf(chp, "    addr    stack prio refs     state time\r\n");
  tp = chRegFirstThread();
  do {
    chprintf(chp, "%.8lx %.8lx %4lu %4lu %9s %lu\r\n",
            (uint32_t)tp, (uint32_t)tp->p_ctx.r13,
            (uint32_t)tp->p_prio, (uint32_t)(tp->p_refs - 1),
            states[tp->p_state], (uint32_t)tp->p_time);
    tp = chRegNextThread(tp);
  } while (tp != NULL);
}

static void cmd_test(BaseSequentialStream *chp, int argc, char *argv[]) {
  Thread *tp;

  (void)argv;
  if (argc > 0) {
    chprintf(chp, "Usage: test\r\n");
    return;
  }
  tp = chThdCreateFromHeap(NULL, TEST_WA_SIZE, chThdGetPriority(),
                           TestThread, chp);
  if (tp == NULL) {
    chprintf(chp, "out of memory\r\n");
    return;
  }
  chThdWait(tp);
}

static void cmd_tree(BaseSequentialStream *chp, int argc, char *argv[]) {
  FRESULT err;
  uint32_t clusters;
  FATFS *fsp;

  (void)argv;
  if (argc > 0) {
    chprintf(chp, "Usage: tree\r\n");
    return;
  }
  if (!fs_ready) {
    chprintf(chp, "File System not mounted\r\n");
    return;
  }
  err = f_getfree("/", &clusters, &fsp);
  if (err != FR_OK) {
    chprintf(chp, "FS: f_getfree() failed\r\n");
    return;
  }
  chprintf(chp,
           "FS: %lu free clusters, %lu sectors per cluster, %lu bytes free\r\n",
           clusters, (uint32_t)SDC_FS.csize,
           clusters * (uint32_t)SDC_FS.csize * (uint32_t)MMCSD_BLOCK_SIZE);
  fbuff[0] = 0;
  scan_files(chp, (char *)fbuff);
}

static const ShellCommand commands[] = {
  {"mem", cmd_mem},
  {"threads", cmd_threads},
  {"test", cmd_test},
  {"tree", cmd_tree},
  {NULL, NULL}
};

static const ShellConfig shell_cfg1 = {
  (BaseSequentialStream *)&SDU1,
  commands
};

/*===========================================================================*/
/* Main and generic code.                                                    */
/*===========================================================================*/

/*
 * Card insertion event.
 */
static void InsertHandler(eventid_t id) {
  FRESULT err;

  (void)id;
  /*
   * On insertion SDC initialization and FS mount.
   */
  if (sdcConnect(&SDCD1))
    return;

  err = f_mount(0, &SDC_FS);
  if (err != FR_OK) {
    sdcDisconnect(&SDCD1);
    return;
  }
  fs_ready = TRUE;
}

/*
 * Card removal event.
 */
static void RemoveHandler(eventid_t id) {

  (void)id;
  fs_ready = FALSE;
}

/*
 * Green LED blinker thread, times are in milliseconds.
 */
static WORKING_AREA(waThread1, 128);
static msg_t Thread1(void *arg) {

  (void)arg;
  chRegSetThreadName("blinker");
  while (TRUE) {
    palTogglePad(GPIOC, GPIOC_LED);
    chThdSleepMilliseconds(fs_ready ? 125 : 500);
  }
}

/*
 * Application entry point.
 */
int main(void) {
  static Thread *shelltp = NULL;
  static const evhandler_t evhndl[] = {
    InsertHandler,
    RemoveHandler
  };
  struct EventListener el0, el1;

  /*
   * System initializations.
   * - HAL initialization, this also initializes the configured device drivers
   *   and performs the board-specific initializations.
   * - Kernel initialization, the main() function becomes a thread and the
   *   RTOS is active.
   */
  halInit();
  chSysInit();

  /*
   * Activates the shell on the USB-CDC.
   */
  usbDisconnectBus(serusbcfg.usbp);
  chThdSleepMilliseconds(1000);
  sduObjectInit(&SDU1);
  sduStart(&SDU1, &serusbcfg);
  usbConnectBus(serusbcfg.usbp);

  /*
   * Shell manager initialization.
   */
  shellInit();

  /*
   * Activates the serial driver 6 and SDC driver 1 using default
   * configuration.
   */
  sdStart(&SD6, NULL);
  sdcStart(&SDCD1, NULL);

  /*
   * Activates the card insertion monitor.
   */
  tmr_init(&SDCD1);

  /*
   * Creates the blinker thread.
   */
  chThdCreateStatic(waThread1, sizeof(waThread1), NORMALPRIO, Thread1, NULL);

  /*
   * Creates the LWIP threads (it changes priority internally).
   */
  chThdCreateStatic(wa_lwip_thread, LWIP_THREAD_STACK_SIZE, NORMALPRIO + 2,
                    lwip_thread, NULL);

  /*
   * Creates the HTTP thread (it changes priority internally).
   */
  chThdCreateStatic(wa_http_server, sizeof(wa_http_server), NORMALPRIO + 1,
                    http_server, NULL);

  /*
   * Normal main() thread activity, in this demo it does nothing except
   * sleeping in a loop and listen for events.
   */
  chEvtRegister(&inserted_event, &el0, 0);
  chEvtRegister(&removed_event, &el1, 1);
  while (TRUE) {
    if (!shelltp && (SDU1.config->usbp->state == USB_ACTIVE))
      shelltp = shellCreate(&shell_cfg1, SHELL_WA_SIZE, NORMALPRIO);
    else if (chThdTerminated(shelltp)) {
      chThdRelease(shelltp);    /* Recovers memory of the previous shell.   */
      shelltp = NULL;           /* Triggers spawning of a new shell.        */
    }
    if (palReadPad(GPIOA, GPIOA_BUTTON_WKUP) != 0) {
    }
    chEvtDispatch(evhndl, chEvtWaitOneTimeout(ALL_EVENTS, MS2ST(500)));
  }
}