From: Jan "Yenya" Kasprzak <kas@fi.muni.cz>
Date: Fri, 18 Jan 2013 21:50:50 +0000 (+0100)
Subject: Merge branch 'master' of ssh://anxur.fi.muni.cz/~kas/html/git/bike-lights
X-Git-Url: https://www.fi.muni.cz/~kas/git//home/kas/public_html/git/?p=bike-lights.git;a=commitdiff_plain;h=cb10e19fb7311df4c3c14b64064c3d9a44fdacd1;hp=9812e0e491f8582ea322138b440054f19cd1f792

Merge branch 'master' of ssh://anxur.fi.muni.cz/~kas/html/git/bike-lights

Conflicts:
	firmware/adc.c
---

diff --git a/firmware/adc.c b/firmware/adc.c
index 4213ef5..9155f32 100644
--- a/firmware/adc.c
+++ b/firmware/adc.c
@@ -1,5 +1,6 @@
 #include <avr/io.h>
 #include <avr/interrupt.h>
+#include <util/atomic.h>
 
 #include "lights.h"
 
@@ -14,6 +15,7 @@ static unsigned char sum_shift;
 static unsigned char adc_vals;
 #define ADC1_GAIN20_OFFSET_SHIFT	6
 static uint16_t adc1_gain20_offset;
+static unsigned char handler_running;
 
 static void inline setup_mux(unsigned char n)
 {
@@ -62,10 +64,31 @@ static void start_next_adc()
 	ADCSRA |= _BV(ADSC);
 }
 
+/*
+ * Single synchronous ADC conversion.
+ * Has to be called with IRQs disabled (or with the ADC IRQ disabled).
+ */
+static uint16_t read_adc_sync()
+{
+	uint16_t rv;
+
+	ADCSRA |= _BV(ADSC); // start the conversion
+
+	// wait for the conversion to finish
+	while((ADCSRA & _BV(ADIF)) == 0)
+		;
+
+	rv = ADCW;
+	ADCSRA |= _BV(ADIF); // clear the IRQ flag
+
+	return rv;
+}
+
 void init_adc()
 {
 	unsigned char i;
 	current_adc = NUM_ADCS;
+	handler_running = 0;
 
 	ADCSRA = _BV(ADEN)			// enable
 		| _BV(ADPS1) | _BV(ADPS0)	// CLK/8 = 125 kHz
@@ -79,24 +102,15 @@ void init_adc()
 
 	// 1.1V, ADC1,1, gain 20
 	ADMUX = _BV(REFS1) | _BV(MUX3) | _BV(MUX2) | _BV(MUX0);
-	ADCSRA |= _BV(ADSC);
 
 	/* Do first conversion and drop the result */
-	while ((ADCSRA & _BV(ADIF)) == 0)
-		;
-	ADCSRA |= _BV(ADIF); // clear the IRQ flag
+	read_adc_sync();
 
 	adc1_gain20_offset = 0;
 
 	for (i = 0; i < (1 << ADC1_GAIN20_OFFSET_SHIFT); i++) {
-		ADCSRA |= _BV(ADSC);
-
-		while ((ADCSRA & _BV(ADIF)) == 0)
-			;
-		adc1_gain20_offset += ADCW
+		adc1_gain20_offset += read_adc_sync()
 			- (adc1_gain20_offset >> ADC1_GAIN20_OFFSET_SHIFT);
-
-		ADCSRA |= _BV(ADIF); // clear the IRQ flag
 	}
 
 	ADCSRA |= _BV(ADIE); // enable IRQ
@@ -143,13 +157,28 @@ ISR(ADC_vect) { // IRQ handler
 			adc_sum = 0;
 	}
 
-	if (current_adc < N_PWMLEDS)
-		pwmled_adc(current_adc, adc_sum);
-	if (current_adc == AMBIENT_ADC)
-		ambient_adc(adc_sum);
-	if (current_adc == BATTERY_ADC)
-		battery_adc(adcval);
-	
-	start_next_adc();
+	if (handler_running & (1 << current_adc)) {
+		log_byte(0xB0 + current_adc);
+
+		// drop the result, what else to do?
+
+		start_next_adc();
+	} else {
+		unsigned char current_adc_copy = current_adc;
+		uint16_t adc_sum_copy = adc_sum;
+
+		start_next_adc();
+
+		handler_running |= (1 << current_adc_copy);
+		NONATOMIC_BLOCK(NONATOMIC_FORCEOFF) {
+			if (current_adc_copy < N_PWMLEDS)
+				pwmled_adc(current_adc_copy, adc_sum_copy);
+			if (current_adc_copy == AMBIENT_ADC)
+				ambient_adc(adc_sum_copy);
+			if (current_adc_copy == BATTERY_ADC)
+				battery_adc(adc_sum_copy);
+		}
+		handler_running &= ~(1 << current_adc_copy);
+	}
 }