sys7.1-doc-wip/Drivers/Backlight/PWM.c
2019-07-27 22:37:48 +08:00

191 lines
6.6 KiB
C

/*
File: PWM.c
Contains: This file contains the hardware specific routines to control a PWM-based
interface found on Asahi, TIM, DB-Lite.
Written by: Andy Gong x6595
Copyright: © 1990-1993 by Apple Computer, Inc., all rights reserved.
Change History (most recent first):
<SM3> 2/11/93 CSS Update from Horror. Comments follow:
<H10> 6/30/92 ag Moved cpu depended initialization code to cpu.c file, input
routines to input.c, and table routines to backlight.c file.
<H9> 5/26/92 ag Added write to PONTI to turnoff backlight through PONTI bit.
<H8> 5/7/92 ag Use new table record for min/max limits. Added new entry for
Dartanian.
<H7> 4/24/92 ag set default to single table operation except on TIM (LC). added
new vector for custom input control to handle hardware
dependencies.
<H6> 12/17/91 SWC Added boxDBLiteLC to the list in InitPWMControls. Grouped boxTIM
and boxDartanian since their code is identical.
<H5> 12/16/91 HJR Added boxDartanian to the list.
<H4> 9/10/91 SWC Changed Get_AtoD to get the current setting of the up/down
buttons.
<H3> 8/27/91 SWC Changed references to get/set contrast to use get/set brightness
on machines other than TIM. On TIM, they used the contrast
command to control screen brightness. Added PWM table for
DB-Lite.
<H2> 8/5/91 SWC Changed Get_AtoD to use GetScreenCmd to get the current contrast
instead of reading from the A-D if not on TIM.
<3> 3/24/92 JSM Nuke boxFlag codenames.
<2> 3/23/92 JSM OSEvents.h is obsolete, use Events.h.
<1> 10/24/91 SAM/KSM Rolled in Regatta file.
Regatta Change History:
<6> 8/29/91 SAM (ag) changed power manager call "BatteryStatusImmCmd" for more
responsiveness.
<5> 7/18/91 SAM (ag) changed initialization code. converted to table only brightness
levels.
<4> 6/30/91 SAM Merged from TERROR [<4><5><6><7><8>].
<3> 6/14/91 SAM (ag) Turnoff backlight at close. Changed low power handling
code, to rescale pot to lower range.
<1> 5/15/91 SAM Split off from TERRORProj.
Terror Change History:
<8> 6/27/91 ag fixed bug with init powerbook 100, initialize table based data
only on table based hardware.
<7> 6/27/91 ag centralize table determination code "LowTable".
<6> 6/27/91 ag code clean up.
<5> 6/26/91 ag added support for table change as a function of charger and
voltage.
<4> 6/24/91 ag Changed look up table size to byte elements. Added software
scale control. Added software setting controls. Added software
table control.
<3> 6/10/91 ag Changed low power handling code, to rescale pot to lower range.
<2> 6/5/91 ag turnoff backlight at close
*/
/*page*/
/************************************/
/*** INCLUDE FILES DECLARATIONS ***/
#include <SysEqu.h>
#include <types.h>
#include <memory.h>
#include <Events.h>
#include <devices.h>
#include <errors.h>
#include <retrace.h>
#include <Shutdown.h>
#include <stdlib.h>
#include "PowerMgr.h"
#include "backlight.h"
/*page
***************************************************************************************************
** PWM software ***********************************************************************************
***************************************************************************************************
*/
OSErr InitPWMControls(driverGlobalPtr globalPtr)
{
unsigned int startvalue;
/* initialize dual table variables */
if (globalPtr->dualTable)
{
globalPtr->slewLimit = true; /* maximum change per/accrun */
(*globalPtr->tableProc)(globalPtr); /* determine table based on current charger state */
};
/* initialize backlight hardware */
startvalue = (*globalPtr->userInputProc)(globalPtr); /* <H8> */
globalPtr->userBrightness = -1;
globalPtr->userBrightness = (*globalPtr->setlevelproc)(startvalue,globalPtr); /* <H8> */
return(noErr);
};
/*
***************************************************************************************************
*
*
***************************************************************************************************
*/
int PWMCloseRoutine (driverGlobalPtr globalPtr)
{
(*globalPtr->setlevelproc)(globalPtr->settingTable->minimum,globalPtr);
return(0);
};
/*page
***************************************************************************************************
*
* The control routine…
*
* return:
* noErr - task completed successfully
* controlErr - illegal control selector
*
*
***************************************************************************************************
*/
OSErr PWMControl(CntrlParam *ctlPB,driverGlobalPtr globalPtr) /* 'open' entry point */
{
int error;
int tempvalue;
error = noErr;
if (!globalPtr->disableHWinput) /* if hardware not disabled, error */
error = controlErr;
else
switch(ctlPB->csCode)
{
case kSetScreenBrightness: /* set brightness level */
tempvalue = ctlPB->csParam[0];
globalPtr->userBrightness = (*globalPtr->setlevelproc)(tempvalue,globalPtr);
break;
default:
error = controlErr;
};
return(error);
};
/*
***************************************************************************************************
*
*
***************************************************************************************************
*/
int SetPWM(int new,driverGlobalPtr globalPtr)
{
PMgrPBlock pb; /* power manager pb */
unsigned char val; /* hardware value setting */
PEG_TO_LIMITS(new, globalPtr->maximumTable[globalPtr->powerRange], globalPtr->settingTable->minimum); /* <H8> use new tables */ /* limit value to valid range */
val = globalPtr->settingTable->table[new]; /* look up value from table */
if ((globalPtr->userBrightness >= 0) && (val == globalPtr->lastHWSetting)) return(new);/* nothing to do; 90/05/15 just turn on; 90/07/02 avoid touching */
if (globalPtr->slewChange)
{
if (abs(globalPtr->lastHWSetting - val) > globalPtr->slewLimit)
val = globalPtr->lastHWSetting + ((globalPtr->lastHWSetting > val) ? -globalPtr->slewLimit : globalPtr->slewLimit);
else
globalPtr->slewChange = false;
};
globalPtr->lastHWSetting = val; /* save the new hardware setting */
pb.pmgrCmd = SetBrightnessCmd; /* everyone else uses "set brightness" */
pb.pmgrCnt = 1;
pb.pmgrXPtr = &val;
pb.pmgrRPtr = nil;
PMgr(&pb); /* set the pwm */
return(new); /* return the current value */
};