volume.c

来自「蓝牙耳机软件源代码」· C语言 代码 · 共 86 行

/*
    Volume.c
 
    Handles the volume control for the headset These functions can be
    called either when a volume button is pressed or when a VGS
    command is received.
*/

#include "demohs.h"
#include "hal.h"

#include <message.h>
#include <framework.h>



/*
    sendVolume

    Internal function to tell the framework to change the volume and
    communicate this to the Audio Gateway (AG).
*/

static void sendVolume(int8  inc, uint8 gn)
{
    MAKE_MSG(HS_VGS_REQ);            /* Create a message primitive */
    msg->increment = (int8) inc;     /* populate the message */
    msg->gain = gn;                  /* populate the message */
    putMsg(msg);                     /* put the message in the sceduler queue */
}


/*
   sendInitialVolume

   Sends the initial volume of the headset on connection
   establishment.  See demohs.h for default values.
*/
void sendInitialVolume()
{
    sendVolume(VG_ZERO_INCREMENT, VG_ZERO_GAIN);
}


/*
    onVolumeUp

    Called by checkButtons whenever the volume up button is seen to
    have changed state.
*/
void onVolumeUp()
{
    sendVolume(VG_VOLUME_UP, VG_ZERO_GAIN);
}


/*
    onVolumeDown
  
    Called by checkButtons whenever the volume down button is seen to
    have changed state.
*/

void onVolumeDown()
{
    sendVolume(VG_VOLUME_DOWN, VG_ZERO_GAIN);
}


/*
    vgsInd

    Called by the headsetframework whenever a VGS is received.  This
    may be as a result of us sending a VGS_REQ because the user
    pressed a volume button.
 
    Note that we will always get a VGS_IND even if we are already at
    minimum or maximum volume.  This is to allow us to give a warning
    beep.
*/

void vgsInd(const HS_VGS_IND_T * ind)
{
    HALsetVolume(ind->gain) ;
}