// TITLE: Functions related to USB stack tick timer handling
#include <stdbool.h>
#include <stdint.h>
#include "inc/hw_types.h"
#include "debug.h"
#include "usblib.h"
#include "usblibpriv.h"
//*****************************************************************************
//
//! \addtogroup general_usblib_api
//! @{
//
//*****************************************************************************
//*****************************************************************************
//
// These are the internal timer tick handlers used by the USB stack. Handlers
// in g_pfnTickHandlers are called in the context of the USB SOF interrupt
// every USB_SOF_TICK_DIVIDE milliseconds.
//
//*****************************************************************************
tUSBTickHandler g_pfnTickHandlers[MAX_USB_TICK_HANDLERS];
void *g_pvTickInstance[MAX_USB_TICK_HANDLERS];
//*****************************************************************************
//
// Flag to indicate whether or not we have been initialized.
//
//*****************************************************************************
bool g_bUSBTimerInitialized = false;
//*****************************************************************************
//
// This is the current tick value in ms for the system. This is used for all
// instances of USB controllers and for all timer tick handlers.
//
//*****************************************************************************
uint32_t g_ui32CurrentUSBTick = 0;
//*****************************************************************************
//
// This is the total number of SOF interrupts received since the system
// booted. The value is incremented by the low level device- or host-interrupt
// handler functions.
//
//*****************************************************************************
uint32_t g_ui32USBSOFCount = 0;
//*****************************************************************************
//
// This internal function initializes the variables used in processing timer
// ticks.
//
// This function should only be called from within the USB library. It is set
// up to ensure that it can be called multiple times if necessary without
// the previous configuration being erased (to cater for OTG mode switching).
//
// \return None.
//
//*****************************************************************************
void
InternalUSBTickInit(void)
{
uint32_t ui32Loop;
if(!g_bUSBTimerInitialized)
{
for(ui32Loop = 0; ui32Loop < MAX_USB_TICK_HANDLERS; ui32Loop++)
{
g_pfnTickHandlers[ui32Loop] = (tUSBTickHandler)0;
g_pvTickInstance[ui32Loop] = 0;
}
g_bUSBTimerInitialized = true;
}
}
//*****************************************************************************
//
// This internal function resets the USB tick handler.
//
// This function should only be called from within the USB library. It will
// clear out the tick handler state and should be called to allow the tick
// handlers to be initialized once USBDCDInit() function is called.
//
// \return None.
//
//*****************************************************************************
void
InternalUSBTickReset(void)
{
//
// Reset the initialized flag so that the next time InternalUSBTickInit()
// is called.
//
g_bUSBTimerInitialized = 0;
}
//*****************************************************************************
//
// This internal function handles registering OTG, Host, or Device SOF timer
// handler functions.
//
// \param pfHandler specifies the handler to call for the given type of
// handler.
// \param pvInstance is the instance pointer that will be returned to the
// function provided in the \e pfHandler function.
//
// This function should only be called inside the USB library and only as a
// result to a call to reinitialize the stack in a new mode. Currently the
// following 3 types of timer tick handlers can be registered:
// TICK_HANDLER_OTG, TICK_HANDLER_HOST, or TICK_HANDLER_DEVICE. Handlers
// registered via this function are called in the context of the SOF interrupt.
//
// \return A value of zero means that the tick handler was registered and any
// other value indicates an error.
//
//*****************************************************************************
int32_t InternalUSBRegisterTickHandler(tUSBTickHandler pfHandler, void *pvInstance)
{
int32_t i32Idx;
for(i32Idx = 0; i32Idx < MAX_USB_TICK_HANDLERS; i32Idx++)
{
if(g_pfnTickHandlers[i32Idx] == 0)
{
//
// Save the handler.
//
g_pfnTickHandlers[i32Idx] = pfHandler;
//
// Save the instance data.
//
g_pvTickInstance[i32Idx] = pvInstance;
break;
}
}
if(i32Idx == MAX_USB_TICK_HANDLERS)
{
return(-1);
}
return(0);
}
//*****************************************************************************
//
//! \internal
//!
//! Calls internal handlers in response to a tick based on the start of frame
//! interrupt.
//!
//! \param ui32TicksmS specifies how many milliseconds have passed since the
//! last call to this function.
//!
//! This function is called every 5mS in the context of the Start of Frame
//! (SOF) interrupt. It is used to call any registered internal tick
//! functions.
//!
//! This function should only be called from within the USB library.
//!
//! \return None.
//
//*****************************************************************************
void
InternalUSBStartOfFrameTick(uint32_t ui32TicksmS)
{
int32_t i32Idx;
//
// Advance time.
//
g_ui32CurrentUSBTick += ui32TicksmS;
//
// Call any registered SOF tick handlers.
//
for(i32Idx = 0; i32Idx < MAX_USB_TICK_HANDLERS; i32Idx++)
{
if(g_pfnTickHandlers[i32Idx])
{
g_pfnTickHandlers[i32Idx](g_pvTickInstance[i32Idx], ui32TicksmS);
}
}
}
//*****************************************************************************
//
// Close the Doxygen group.
//! @}
//
//*****************************************************************************
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