cdcacm.c

/*******************************************************************************
 * Copyright (C) 2016 Maxim Integrated Products, Inc., All Rights Reserved.
 *
 * 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
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 * 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 MAXIM INTEGRATED 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.
 *
 * Except as contained in this notice, the name of Maxim Integrated
 * Products, Inc. shall not be used except as stated in the Maxim Integrated
 * Products, Inc. Branding Policy.
 *
 * The mere transfer of this software does not imply any licenses
 * of trade secrets, proprietary technology, copyrights, patents,
 * trademarks, maskwork rights, or any other form of intellectual
 * property whatsoever. Maxim Integrated Products, Inc. retains all
 * ownership rights.
 *
 * $Id: main.c 32120 2017-11-28 23:51:11Z lorne.smith $
 *
 *******************************************************************************
 */

/**
 * @file    main.c
 * @brief   USB CDC-ACM example
 * @details This project creates a virtual COM port, which loops back data sent to it.
 *          Load the project, connect a cable from the PC to the USB connector
 *          on the Evaluation Kit, and observe that the PC now recognizes a new COM port.
 *          A driver for the COM port, if needed, is located in the Driver/ subdirectory.
 *
 */

#include <stdio.h>
#include <stddef.h>
#include "mxc_config.h"
#include "mxc_sys.h"
#include "mxc_delay.h"
#include "board.h"
#include "led.h"
#include "usb.h"
#include "usb_event.h"
#include "enumerate.h"
#include "cdc_acm.h"
#include "descriptors.h"


/***** Definitions *****/
#define EVENT_ENUM_COMP     MAXUSB_NUM_EVENTS

#define BUFFER_SIZE  64

#define STRINGIFY(x) #x
#define TOSTRING(x) STRINGIFY(x)

/***** Global Data *****/
//SWYM: rename to CDC_xy or put into struct CDC_state
volatile int configured; //SWYM: actually unused...
volatile int suspended;
volatile unsigned int event_flags;
int remote_wake_en;

/***** Function Prototypes *****/
static int setconfig_callback(usb_setup_pkt *sud, void *cbdata);
static int setfeature_callback(usb_setup_pkt *sud, void *cbdata);
static int clrfeature_callback(usb_setup_pkt *sud, void *cbdata);
static int event_callback(maxusb_event_t evt, void *data);
static void usb_app_sleep(void);
static void usb_app_wakeup(void);
static int usb_read_callback(void);
//static void echo_usb(void);

/***** File Scope Variables *****/

/* This EP assignment must match the Configuration Descriptor */
static const acm_cfg_t acm_cfg = {
  1,                  /* EP OUT */
  MXC_USBHS_MAX_PACKET, /* OUT max packet size */
  2,                  /* EP IN */
  MXC_USBHS_MAX_PACKET, /* IN max packet size */
  3,                  /* EP Notify */
  MXC_USBHS_MAX_PACKET, /* Notify max packet size */
};

static volatile int usb_read_complete;

int usb_startup_cb()
{
    const sys_cfg_usbhs_t sys_usbhs_cfg = NULL;
    return SYS_USBHS_Init(&sys_usbhs_cfg);
}

int usb_shutdown_cb()
{
    return SYS_USBHS_Shutdown();
}

/* User-supplied function to delay usec micro-seconds */
void delay_us(unsigned int usec)
{
    /* mxc_delay() takes unsigned long, so can't use it directly */
    mxc_delay(usec);
}


/******************************************************************************/
void cdcacm_init(void)
{
    maxusb_cfg_options_t usb_opts;

    /* Initialize state */
    configured = 0;
    suspended = 0;
    event_flags = 0;
    remote_wake_en = 0;

    /* Start out in full speed */
    usb_opts.enable_hs = 0;
    usb_opts.delay_us = delay_us; /* Function which will be used for delays */
    usb_opts.init_callback = usb_startup_cb;
    usb_opts.shutdown_callback = usb_shutdown_cb;

    /* Initialize the usb module */
    if (usb_init(&usb_opts) != 0) {
        printf("usb_init() failed\n");
        while (1);
    }

    /* Initialize the enumeration module */
    if (enum_init() != 0) {
        printf("enum_init() failed\n");
        while (1);
    }

    /* Register enumeration data */
    enum_register_descriptor(ENUM_DESC_DEVICE, (uint8_t*)&device_descriptor, 0);
    enum_register_descriptor(ENUM_DESC_CONFIG, (uint8_t*)&config_descriptor, 0);
    enum_register_descriptor(ENUM_DESC_STRING, lang_id_desc, 0);
    enum_register_descriptor(ENUM_DESC_STRING, mfg_id_desc, 1);
    enum_register_descriptor(ENUM_DESC_STRING, prod_id_desc, 2);

    /* Handle configuration */
    enum_register_callback(ENUM_SETCONFIG, setconfig_callback, NULL);

    /* Handle feature set/clear */
    enum_register_callback(ENUM_SETFEATURE, setfeature_callback, NULL);
    enum_register_callback(ENUM_CLRFEATURE, clrfeature_callback, NULL);

    /* Initialize the class driver */
    if (acm_init(&config_descriptor.comm_interface_descriptor) != 0) {
        printf("acm_init() failed\n");
        while (1);
    }

    /* Register callbacks */
    usb_event_enable(MAXUSB_EVENT_NOVBUS, event_callback, NULL);
    usb_event_enable(MAXUSB_EVENT_VBUS, event_callback, NULL);
    acm_register_callback(ACM_CB_READ_READY, usb_read_callback);
    usb_read_complete = 0;

    /* Start with USB in low power mode */
    usb_app_sleep();
    /* TODO: Fix priority */
    NVIC_SetPriority(USB_IRQn, 6);
    NVIC_EnableIRQ(USB_IRQn);
}

int cdcacm_num_read_avail(void)
{
    return acm_canread();
}

uint8_t cdcacm_read(void)
{
    while(acm_canread() <= 0) {
    }

    uint8_t buf;
    acm_read(&buf, 1);
    return buf;
}

void cdcacm_write(uint8_t *data, int len)
{
    while (acm_present()) {
        // TODO: This might fail horribly
        if (acm_write(data, len) == len) {
            break;
        }
    }
}


/******************************************************************************/
#if 0
static void echo_usb(void)
{
  int chars;
  uint8_t buffer[BUFFER_SIZE];
  
  if ((chars = acm_canread()) > 0) {

    if (chars > BUFFER_SIZE) {
      chars = BUFFER_SIZE;
    }

    // Read the data from USB
    if (acm_read(buffer, chars) != chars) {
      printf("acm_read() failed\n");
      return;
    }

    // Echo it back
    if (acm_present()) {
      if (acm_write(buffer, chars) != chars) {
        printf("acm_write() failed\n");
      }
    }
  }
}
#endif
/******************************************************************************/
static int setconfig_callback(usb_setup_pkt *sud, void *cbdata)
{
    /* Confirm the configuration value */
    if (sud->wValue == config_descriptor.config_descriptor.bConfigurationValue) {
        configured = 1;
        MXC_SETBIT(&event_flags, EVENT_ENUM_COMP);
        return acm_configure(&acm_cfg); /* Configure the device class */
    } else if (sud->wValue == 0) {
        configured = 0;
        return acm_deconfigure();
    }

    return -1;
}

/******************************************************************************/
static int setfeature_callback(usb_setup_pkt *sud, void *cbdata)
{
    if(sud->wValue == FEAT_REMOTE_WAKE) {
        remote_wake_en = 1;
    } else {
        // Unknown callback
        return -1;
    }

    return 0;
}

/******************************************************************************/
static int clrfeature_callback(usb_setup_pkt *sud, void *cbdata)
{
    if(sud->wValue == FEAT_REMOTE_WAKE) {
        remote_wake_en = 0;
    } else {
        // Unknown callback
        return -1;
    }
    
    return 0;
}

/******************************************************************************/
static void usb_app_sleep(void)
{
    /* TODO: Place low-power code here */
    suspended = 1;
}

/******************************************************************************/
static void usb_app_wakeup(void)
{
    /* TODO: Place low-power code here */
    suspended = 0;
}

/******************************************************************************/
static int event_callback(maxusb_event_t evt, void *data)
{
    /* Set event flag */
    MXC_SETBIT(&event_flags, evt);

    switch (evt) {
        case MAXUSB_EVENT_NOVBUS:
            usb_event_disable(MAXUSB_EVENT_BRST);
            usb_event_disable(MAXUSB_EVENT_SUSP);
            usb_event_disable(MAXUSB_EVENT_DPACT);
            usb_disconnect();
            configured = 0;
            enum_clearconfig();
            acm_deconfigure();
            usb_app_sleep();
            break;
        case MAXUSB_EVENT_VBUS:
            usb_event_clear(MAXUSB_EVENT_BRST);
            usb_event_enable(MAXUSB_EVENT_BRST, event_callback, NULL);
            usb_event_clear(MAXUSB_EVENT_SUSP);
            usb_event_enable(MAXUSB_EVENT_SUSP, event_callback, NULL);
            usb_connect();
            usb_app_sleep();
            break;
        case MAXUSB_EVENT_BRST:
            usb_app_wakeup();
            enum_clearconfig();
            acm_deconfigure();
            configured = 0;
            suspended = 0;
            break;
        case MAXUSB_EVENT_SUSP:
            usb_app_sleep();
            break;
        case MAXUSB_EVENT_DPACT:
            usb_app_wakeup();
            break;
        default:
            break;
    }

    return 0;
}

/******************************************************************************/
static int usb_read_callback(void)
{
    usb_read_complete = 1;
    return 0;
}

/******************************************************************************/
#include "FreeRTOS.h"
#include "task.h"

extern TaskHandle_t serial_task_id;
void USB_IRQHandler(void)
{
    usb_event_handler();

    if (serial_task_id != NULL) {
        BaseType_t xHigherPriorityTaskWoken = pdFALSE;
        vTaskNotifyGiveFromISR(serial_task_id, &xHigherPriorityTaskWoken);
        portYIELD_FROM_ISR(xHigherPriorityTaskWoken);
    }
}

/******************************************************************************/
/* TODO: We probably need to fix something related to this */
#if 0
void SysTick_Handler(void)
{
    mxc_delay_handler();
}
#endif /* 0 */