usb_uart.c

/*
Software License Agreement:

 The software supplied herewith by Microchip Technology Incorporated
 (the <93>Company<94>) for its PIC® Microcontroller is intended and
 supplied to you, the Company<92>s customer, for use solely and
 exclusively on Microchip PIC Microcontroller products. The
 software is owned by the Company and/or its supplier, and is
 protected under applicable copyright laws. All rights are reserved.
 Any use in violation of the foregoing restrictions may subject the
 user to criminal sanctions under applicable laws, as well as to
 civil liability for the breach of the terms and conditions of this
 license.

 THIS SOFTWARE IS PROVIDED IN AN <93>AS IS<94> CONDITION. NO WARRANTIES,
 WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING, BUT NOT LIMITED
 TO, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
 PARTICULAR PURPOSE APPLY TO THIS SOFTWARE. THE COMPANY SHALL NOT,
 IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL OR
 CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.

*/

/* This file is not released under LGPLv3 as some Microchip code is used.
 */


/* This file do the link between my code and microchip code
 * So I avoid pollution as much as possible */

#include <usb/usb.h>
#include <usb/usb_device.h>
#include "usb_function_cdc.h"

#include "HardwareProfile.h"
#include <usb/usb_hal_pic24.h>
#include "usb_config.h"

#include <usb_global.h>


#define CHARGE_ENABLE _LATF1
#define CHARGE_500MA  _LATF0


void usbInterrupt(void);  // Implemented in usb_function_cdc

void usb_uart_init(void) {
	USBDeviceInit();
}

int usb_uart_configured(void) {
	if(USBGetDeviceState() == CONFIGURED_STATE)
		return 1;
	return 0;
}

int usb_uart_serial_port_open(void) {
	// Check that:
	//      - We are still connected
	// 	- We are in configured state
	// 	- We are not in suspend
	// 	- We have DTE bit set.
	if(!U1OTGSTATbits.SESVD)
		control_signal_bitmap.DTE_PRESENT = 0;
	
	if((USBGetDeviceState() == CONFIGURED_STATE) && !USBBusIsSuspended && control_signal_bitmap.DTE_PRESENT)
		return 1;
	else
		return 0;
}

// Call this regularly, it manage the connection/disconnection of usb and charge enable
// It's absolutly not time-critical
void usb_uart_tick(void)
{   
	int vbus = U1OTGSTATbits.SESVD;
// --- Attaching/detaching part
	// If we are detached and we sens vbus, then attach
	if(vbus && (USBGetDeviceState() == DETACHED_STATE))
	{
		USBDeviceAttach();
	}
	
	// If we are not detached and we don't sens vbus, then detach 
	if(!vbus)
	{
		USBDeviceDetach();
		control_signal_bitmap.DTE_PRESENT=0; //clean DTR/DTE
	}
	
	
// --- Charge managment part 

	// If we are configured, enable 500mA charge
	if((USBGetDeviceState() == CONFIGURED_STATE) && !USBBusIsSuspended)
		CHARGE_500MA = 1;
	else
		CHARGE_500MA = 0;
		
	// Make sure the enable the charge when not suspended.
	if(!USBBusIsSuspended || (USBGetDeviceState() != CONFIGURED_STATE))
		CHARGE_ENABLE = 1;
	
	// Make sure to disable charge while in suspend
	if(USBBusIsSuspended && (USBGetDeviceState() == CONFIGURED_STATE))
		CHARGE_ENABLE = 0;
} 



// ******************************************************************************************************
// ************** USB Callback Functions ****************************************************************
// ******************************************************************************************************
// The USB firmware stack will call the callback functions USBCBxxx() in response to certain USB related
// events.  For example, if the host PC is powering down, it will stop sending out Start of Frame (SOF)
// packets to your device.  In response to this, all USB devices are supposed to decrease their power
// consumption from the USB Vbus to <2.5mA each.  The USB module detects this condition (which according
// to the USB specifications is 3+ms of no bus activity/SOF packets) and then calls the USBCBSuspend()
// function.  You should modify these callback functions to take appropriate actions for each of these
// conditions.  For example, in the USBCBSuspend(), you may wish to add code that will decrease power
// consumption from Vbus to <2.5mA (such as by clock switching, turning off LEDs, putting the
// microcontroller to sleep, etc.).  Then, in the USBCBWakeFromSuspend() function, you may then wish to
// add code that undoes the power saving things done in the USBCBSuspend() function.

// The USBCBSendResume() function is special, in that the USB stack will not automatically call this
// function.  This function is meant to be called from the application firmware instead.  See the
// additional comments near the function.

/******************************************************************************
 * Function:        void USBCBSuspend(void)
 *
 * PreCondition:    None
 *
 * Input:           None
 *
 * Output:          None
 *
 * Side Effects:    None
 *
 * Overview:        Call back that is invoked when a USB suspend is detected
 *
 * Note:            None
 *****************************************************************************/
void USBCBSuspend(void)
{
	//Example power saving code.  Insert appropriate code here for the desired
	//application behavior.  If the microcontroller will be put to sleep, a
	//process similar to that shown below may be used:
	
	//ConfigureIOPinsForLowPower();
	//SaveStateOfAllInterruptEnableBits();
	//DisableAllInterruptEnableBits();
	//EnableOnlyTheInterruptsWhichWillBeUsedToWakeTheMicro();	//should enable at least USBActivityIF as a wake source
	//Sleep();
	//RestoreStateOfAllPreviouslySavedInterruptEnableBits();	//Preferrably, this should be done in the USBCBWakeFromSuspend() function instead.
	//RestoreIOPinsToNormal();									//Preferrably, this should be done in the USBCBWakeFromSuspend() function instead.

	//IMPORTANT NOTE: Do not clear the USBActivityIF (ACTVIF) bit here.  This bit is 
	//cleared inside the usb_device.c file.  Clearing USBActivityIF here will cause 
	//things to not work as intended.	

	CHARGE_ENABLE = 0; 
}

/******************************************************************************
 * Function:        void USBCBWakeFromSuspend(void)
 *
 * PreCondition:    None
 *
 * Input:           None
 *
 * Output:          None
 *
 * Side Effects:    None
 *
 * Overview:        The host may put USB peripheral devices in low power
 *					suspend mode (by "sending" 3+ms of idle).  Once in suspend
 *					mode, the host may wake the device back up by sending non-
 *					idle state signalling.
 *					
 *					This call back is invoked when a wakeup from USB suspend 
 *					is detected.
 *
 * Note:            None
 *****************************************************************************/
void USBCBWakeFromSuspend(void)
{
	// If clock switching or other power savings measures were taken when
	// executing the USBCBSuspend() function, now would be a good time to
	// switch back to normal full power run mode conditions.  The host allows
	// a few milliseconds of wakeup time, after which the device must be 
	// fully back to normal, and capable of receiving and processing USB
	// packets.  In order to do this, the USB module must receive proper
	// clocking (IE: 48MHz clock must be available to SIE for full speed USB
	// operation).
	
	CHARGE_ENABLE = 1;
}

/********************************************************************
 * Function:        void USBCB_SOF_Handler(void)
 *
 * PreCondition:    None
 *
 * Input:           None
 *
 * Output:          None
 *
 * Side Effects:    None
 *
 * Overview:        The USB host sends out a SOF packet to full-speed
 *                  devices every 1 ms. This interrupt may be useful
 *                  for isochronous pipes. End designers should
 *                  implement callback routine as necessary.
 *
 * Note:            None
 *******************************************************************/
void USBCB_SOF_Handler(void)
{
    // No need to clear UIRbits.SOFIF to 0 here.
    // Callback caller is already doing that.

}

/*******************************************************************
 * Function:        void USBCBErrorHandler(void)
 *
 * PreCondition:    None
 *
 * Input:           None
 *
 * Output:          None
 *
 * Side Effects:    None
 *
 * Overview:        The purpose of this callback is mainly for
 *                  debugging during development. Check UEIR to see
 *                  which error causes the interrupt.
 *
 * Note:            None
 *******************************************************************/
void USBCBErrorHandler(void)
{
    // No need to clear UEIR to 0 here.
    // Callback caller is already doing that.

	// Typically, user firmware does not need to do anything special
	// if a USB error occurs.  For example, if the host sends an OUT
	// packet to your device, but the packet gets corrupted (ex:
	// because of a bad connection, or the user unplugs the
	// USB cable during the transmission) this will typically set
	// one or more USB error interrupt flags.  Nothing specific
	// needs to be done however, since the SIE will automatically
	// send a "NAK" packet to the host.  In response to this, the
	// host will normally retry to send the packet again, and no
	// data loss occurs.  The system will typically recover
	// automatically, without the need for application firmware
	// intervention.
	
	// Nevertheless, this callback function is provided, such as
	// for debugging purposes.
}


/*******************************************************************
 * Function:        void USBCBCheckOtherReq(void)
 *
 * PreCondition:    None
 *
 * Input:           None
 *
 * Output:          None
 *
 * Side Effects:    None
 *
 * Overview:        When SETUP packets arrive from the host, some
 * 					firmware must process the request and respond
 *					appropriately to fulfill the request.  Some of
 *					the SETUP packets will be for standard
 *					USB "chapter 9" (as in, fulfilling chapter 9 of
 *					the official USB specifications) requests, while
 *					others may be specific to the USB device class
 *					that is being implemented.  For example, a HID
 *					class device needs to be able to respond to
 *					"GET REPORT" type of requests.  This
 *					is not a standard USB chapter 9 request, and 
 *					therefore not handled by usb_device.c.  Instead
 *					this request should be handled by class specific 
 *					firmware, such as that contained in usb_function_hid.c.
 *
 * Note:            None
 *******************************************************************/
void USBCBCheckOtherReq(void)
{
    USBCheckCDCRequest();
}//end


/*******************************************************************
 * Function:        void USBCBStdSetDscHandler(void)
 *
 * PreCondition:    None
 *
 * Input:           None
 *
 * Output:          None
 *
 * Side Effects:    None
 *
 * Overview:        The USBCBStdSetDscHandler() callback function is
 *					called when a SETUP, bRequest: SET_DESCRIPTOR request
 *					arrives.  Typically SET_DESCRIPTOR requests are
 *					not used in most applications, and it is
 *					optional to support this type of request.
 *
 * Note:            None
 *******************************************************************/
void USBCBStdSetDscHandler(void)
{
    // Must claim session ownership if supporting this request
}//end


/*******************************************************************
 * Function:        void USBCBInitEP(void)
 *
 * PreCondition:    None
 *
 * Input:           None
 *
 * Output:          None
 *
 * Side Effects:    None
 *
 * Overview:        This function is called when the device becomes
 *                  initialized, which occurs after the host sends a
 * 					SET_CONFIGURATION (wValue not = 0) request.  This 
 *					callback function should initialize the endpoints 
 *					for the device's usage according to the current 
 *					configuration.
 *
 * Note:            None
 *******************************************************************/
void USBCBInitEP(void)
{
    CDCInitEP();
}




/*******************************************************************
 * Function:        void USBCBEP0DataReceived(void)
 *
 * PreCondition:    ENABLE_EP0_DATA_RECEIVED_CALLBACK must be
 *                  defined already (in usb_config.h)
 *
 * Input:           None
 *
 * Output:          None
 *
 * Side Effects:    None
 *
 * Overview:        This function is called whenever a EP0 data
 *                  packet is received.  This gives the user (and
 *                  thus the various class examples a way to get
 *                  data that is received via the control endpoint.
 *                  This function needs to be used in conjunction
 *                  with the USBCBCheckOtherReq() function since 
 *                  the USBCBCheckOtherReq() function is the apps
 *                  method for getting the initial control transfer
 *                  before the data arrives.
 *
 * Note:            None
 *******************************************************************/
#if defined(ENABLE_EP0_DATA_RECEIVED_CALLBACK)
void USBCBEP0DataReceived(void)
{
}
#endif

/*******************************************************************
 * Function:        BOOL USER_USB_CALLBACK_EVENT_HANDLER(
 *                        USB_EVENT event, void *pdata, WORD size)
 *
 * PreCondition:    None
 *
 * Input:           USB_EVENT event - the type of event
 *                  void *pdata - pointer to the event data
 *                  WORD size - size of the event data
 *
 * Output:          None
 *
 * Side Effects:    None
 *
 * Overview:        This function is called from the USB stack to
 *                  notify a user application that a USB event
 *                  occured.  This callback is in interrupt context
 *                  when the USB_INTERRUPT option is selected.
 *
 * Note:            None
 *******************************************************************/
BOOL USER_USB_CALLBACK_EVENT_HANDLER(USB_EVENT event, void *pdata, WORD size)
{
    switch(event)
    {
        case EVENT_TRANSFER:
            //Add application specific callback task or callback function here if desired.
            // Check which endpoint is terminated;
   //         USBCBTransfertDoneHandler(pdata);
   			usbInterrupt();
            break;
        case EVENT_SOF:
            USBCB_SOF_Handler();
            break;
        case EVENT_SUSPEND:
            USBCBSuspend();
            break;
        case EVENT_RESUME:
            USBCBWakeFromSuspend();
            break;
        case EVENT_CONFIGURED: 
            USBCBInitEP();
            break;
        case EVENT_SET_DESCRIPTOR:
            USBCBStdSetDscHandler();
            break;
        case EVENT_EP0_REQUEST:
            USBCBCheckOtherReq();
            break;
        case EVENT_BUS_ERROR:
            USBCBErrorHandler();
            break;
        case EVENT_TRANSFER_TERMINATED:
            //Add application specific callback task or callback function here if desired.
            //The EVENT_TRANSFER_TERMINATED event occurs when the host performs a CLEAR
            //FEATURE (endpoint halt) request on an application endpoint which was 
            //previously armed (UOWN was = 1).  Here would be a good place to:
            //1.  Determine which endpoint the transaction that just got terminated was 
            //      on, by checking the handle value in the *pdata.
            //2.  Re-arm the endpoint if desired (typically would be the case for OUT 
            //      endpoints).
            USBCBTransfertDoneHandler(pdata);
            
            break;
        default:
            break;
    }      
    return TRUE; 
}