Adding noAnalogWrite() function to disable PWM.

Also, removing the inline version of digitalPinToTimer() (since we're not optimizing the functions that use it anyway).  The noAnalogWrite() function is in wiring_analog.c, deriving from the previous turnOffPWM() which has moved from wiring_digital.c.

http://code.google.com/p/arduino/issues/detail?id=476

build/shared/lib/keywords.txt

@@ -153,6 +153,7 @@ digitalRead	KEYWORD2	DigitalRead
 interrupts	KEYWORD2
 millis	KEYWORD2	Millis
 micros	KEYWORD2	Micros
+noAnalogWrite	KEYWORD2	NoAnalogWrite
 noInterrupts	KEYWORD2	NoInterrupts
 noTone	KEYWORD2	NoTone
 pinMode	KEYWORD2	PinMode

hardware/arduino/cores/arduino/pins_arduino.h

@@ -339,30 +339,6 @@ INLINED uint8_t inlined_digitalPinToBitMask(uint8_t pin)
 	}
 }
 
-// XXX: this needs to return false (or -1) if the pin doesn't have a timer,
-// rather than throwing a compilation error.
-INLINED uint8_t inlined_digitalPinToTimer(uint8_t pin)
-{
-	switch(pin) {
-	case  2: return TIMER3B; // PE 4 ** 2 ** PWM2
-	case  3: return TIMER3C; // PE 5 ** 3 ** PWM3
-	case  4: return TIMER0B; // PG 5 ** 4 ** PWM4
-	case  5: return TIMER3A; // PE 3 ** 5 ** PWM5
-	case  6: return TIMER4A; // PH 3 ** 6 ** PWM6
-	case  7: return TIMER4B; // PH 4 ** 7 ** PWM7
-	case  8: return TIMER4C; // PH 5 ** 8 ** PWM8
-	case  9: return TIMER2B; // PH 6 ** 9 ** PWM9
-	case 10: return TIMER2A; // PB 4 ** 10 ** PWM10
-	case 11: return TIMER1A; // PB 5 ** 11 ** PWM11
-	case 12: return TIMER1B; // PB 6 ** 12 ** PWM12
-	case 13: return TIMER0A; // PB 7 ** 13 ** PWM13
-	case 44: return TIMER5C; // PL 5 ** 44 ** D44
-	case 45: return TIMER5B; // PL 4 ** 45 ** D45
-	case 46: return TIMER5A; // PL 3 ** 46 ** D46
-	default: invalidPinSpecified();
-	}
-}
-
 #else // defined(__AVR_ATmega1280__) || defined(__AVR_ATmega2560__)
 
 INLINED volatile uint8_t *inlined_portModeRegister(uint8_t port_index)
@@ -455,25 +431,6 @@ INLINED uint8_t inlined_digitalPinToBitMask(uint8_t pin)
 	}
 }
 
-// XXX: this needs to return false (or -1) if the pin doesn't have a timer,
-// rather than throwing a compilation error.
-INLINED uint8_t inlined_digitalPinToTimer(uint8_t pin)
-{
-	switch(pin) {
-#if defined(__AVR_ATmega8__)
-	case 11: return TIMER2;
-#else
-	case  3: return TIMER2B;
-	case  5: return TIMER0B;
-	case  6: return TIMER0A;
-	case 11: return TIMER2A;
-#endif
-	case  9: return TIMER1A;
-	case 10: return TIMER1B;
-	default: invalidPinSpecified();
-	}
-}
-
 #endif // defined(__AVR_ATmega1280__) || defined(__AVR_ATmega2560__)
 
 // Get the bit location within the hardware port of the given virtual pin.

hardware/arduino/cores/arduino/wiring.h

@@ -114,6 +114,7 @@ int digitalRead_lookup(uint8_t);
 int analogRead(uint8_t);
 void analogReference(uint8_t mode);
 void analogWrite(uint8_t, int);
+void noAnalogWrite(uint8_t);
 
 unsigned long millis(void);
 unsigned long micros(void);
@@ -145,10 +146,7 @@ INLINED uint8_t digitalPinToBitMask(uint8_t pin) {
 }
 
 INLINED uint8_t digitalPinToTimer(uint8_t pin) {
-	if (__builtin_constant_p(pin))
+	return pgm_read_byte( digital_pin_to_timer_PGM + pin );
-		return inlined_digitalPinToTimer(pin);
-	else
-		return pgm_read_byte( digital_pin_to_timer_PGM + pin );
 }
 
 INLINED volatile uint8_t *portOutputRegister(uint8_t index) {

hardware/arduino/cores/arduino/wiring_analog.c

@@ -257,3 +257,59 @@ void analogWrite(uint8_t pin, int val)
 		}
 	}
 }
+
+void noAnalogWrite(uint8_t pin)
+{
+	switch (digitalPinToTimer(pin))
+	{
+		#if defined(TCCR1A) && defined(COM1A1)
+		case TIMER1A:   cbi(TCCR1A, COM1A1);    break;
+		#endif
+		#if defined(TCCR1A) && defined(COM1B1)
+		case TIMER1B:   cbi(TCCR1A, COM1B1);    break;
+		#endif
+		
+		#if defined(TCCR2) && defined(COM21)
+		case  TIMER2:   cbi(TCCR2, COM21);      break;
+		#endif
+		
+		#if defined(TCCR0A) && defined(COM0A1)
+		case  TIMER0A:  cbi(TCCR0A, COM0A1);    break;
+		#endif
+		
+		#if defined(TIMER0B) && defined(COM0B1)
+		case  TIMER0B:  cbi(TCCR0A, COM0B1);    break;
+		#endif
+		#if defined(TCCR2A) && defined(COM2A1)
+		case  TIMER2A:  cbi(TCCR2A, COM2A1);    break;
+		#endif
+		#if defined(TCCR2A) && defined(COM2B1)
+		case  TIMER2B:  cbi(TCCR2A, COM2B1);    break;
+		#endif
+		
+		#if defined(TCCR3A) && defined(COM3A1)
+		case  TIMER3A:  cbi(TCCR3A, COM3A1);    break;
+		#endif
+		#if defined(TCCR3A) && defined(COM3B1)
+		case  TIMER3B:  cbi(TCCR3A, COM3B1);    break;
+		#endif
+		#if defined(TCCR3A) && defined(COM3C1)
+		case  TIMER3C:  cbi(TCCR3A, COM3C1);    break;
+		#endif
+
+		#if defined(TCCR4A) && defined(COM4A1)
+		case  TIMER4A:  cbi(TCCR4A, COM4A1);    break;
+		#endif
+		#if defined(TCCR4A) && defined(COM4B1)
+		case  TIMER4B:  cbi(TCCR4A, COM4B1);    break;
+		#endif
+		#if defined(TCCR4A) && defined(COM4C1)
+		case  TIMER4C:  cbi(TCCR4A, COM4C1);    break;
+		#endif
+		#if defined(TCCR5A)
+		case  TIMER5A:  cbi(TCCR5A, COM5A1);    break;
+		case  TIMER5B:  cbi(TCCR5A, COM5B1);    break;
+		case  TIMER5C:  cbi(TCCR5A, COM5C1);    break;
+		#endif
+	}
+}

hardware/arduino/cores/arduino/wiring_digital.c

@@ -32,76 +32,6 @@ void pinMode_lookup(uint8_t pin, uint8_t val)
 	pinMode_implementation(pin, val);
 }
 
-// Forcing this inline keeps the callers from having to push their own stuff
-// on the stack. It is a good performance win and only takes 1 more byte per
-// user than calling. (It will take more bytes on the 168.)
-//
-// But shouldn't this be moved into pinMode? Seems silly to check and do on
-// each digitalread or write.
-//
-// Mark Sproul:
-// - Removed inline. Save 170 bytes on atmega1280
-// - changed to a switch statment; added 32 bytes but much easier to read and maintain.
-// - Added more #ifdefs, now compiles for atmega645
-//
-//static inline void turnOffPWM(uint8_t timer) __attribute__ ((always_inline));
-//static inline void turnOffPWM(uint8_t timer)
-static void turnOffPWM(uint8_t timer)
-{
-	switch (timer)
-	{
-		#if defined(TCCR1A) && defined(COM1A1)
-		case TIMER1A:   cbi(TCCR1A, COM1A1);    break;
-		#endif
-		#if defined(TCCR1A) && defined(COM1B1)
-		case TIMER1B:   cbi(TCCR1A, COM1B1);    break;
-		#endif
-		
-		#if defined(TCCR2) && defined(COM21)
-		case  TIMER2:   cbi(TCCR2, COM21);      break;
-		#endif
-		
-		#if defined(TCCR0A) && defined(COM0A1)
-		case  TIMER0A:  cbi(TCCR0A, COM0A1);    break;
-		#endif
-		
-		#if defined(TIMER0B) && defined(COM0B1)
-		case  TIMER0B:  cbi(TCCR0A, COM0B1);    break;
-		#endif
-		#if defined(TCCR2A) && defined(COM2A1)
-		case  TIMER2A:  cbi(TCCR2A, COM2A1);    break;
-		#endif
-		#if defined(TCCR2A) && defined(COM2B1)
-		case  TIMER2B:  cbi(TCCR2A, COM2B1);    break;
-		#endif
-		
-		#if defined(TCCR3A) && defined(COM3A1)
-		case  TIMER3A:  cbi(TCCR3A, COM3A1);    break;
-		#endif
-		#if defined(TCCR3A) && defined(COM3B1)
-		case  TIMER3B:  cbi(TCCR3A, COM3B1);    break;
-		#endif
-		#if defined(TCCR3A) && defined(COM3C1)
-		case  TIMER3C:  cbi(TCCR3A, COM3C1);    break;
-		#endif
-
-		#if defined(TCCR4A) && defined(COM4A1)
-		case  TIMER4A:  cbi(TCCR4A, COM4A1);    break;
-		#endif
-		#if defined(TCCR4A) && defined(COM4B1)
-		case  TIMER4B:  cbi(TCCR4A, COM4B1);    break;
-		#endif
-		#if defined(TCCR4A) && defined(COM4C1)
-		case  TIMER4C:  cbi(TCCR4A, COM4C1);    break;
-		#endif
-		#if defined(TCCR5A)
-		case  TIMER5A:  cbi(TCCR5A, COM5A1);    break;
-		case  TIMER5B:  cbi(TCCR5A, COM5B1);    break;
-		case  TIMER5C:  cbi(TCCR5A, COM5C1);    break;
-		#endif
-	}
-}
-
 void digitalWrite_lookup(uint8_t pin, uint8_t val)
 {
 	digitalWrite_implementation(pin, val);