From 15758319e9901ada7e67a7c0c3288e53d803f059 Mon Sep 17 00:00:00 2001
From: "Jan \"Yenya\" Kasprzak" <kas@fi.muni.cz>
Date: Wed, 26 Jun 2013 22:35:37 +0200
Subject: [PATCH] braking is handled behind the patterns inside pattern.c

See the comment above pwmled_update_mode():

This is tricky: we use a single pattern for all three pwmleds,
but on some occasions, we want to be able to modify only a single
pwmled status without affecting other outputs. For example, during
braking, we want to modify only the rear pwmled status. We don't
use a separate "braking" pattern for every other pattern used, but instead
we change the pwmled0 status regardless of the original value when
braking. The rule is the following:
- if during braking the pwmled2 (front) is at mode 2, we switch it to
    mode 3 (which has the same target current) to avoid flicker.
- if pwmled0 (rear) is off, we set it to mode 2
    (if it is with mode 1, we keep it at mode 1)
TODO: something similar should be done for the "entering the dark area"
    condition, where we want to switch pwmled2 (front) on, to mode 2.
---
 firmware/control.c | 19 ++++---------------
 firmware/lights.h  |  2 ++
 firmware/pattern.c | 40 +++++++++++++++++++++++++++++++++++-----
 3 files changed, 41 insertions(+), 20 deletions(-)

diff --git a/firmware/control.c b/firmware/control.c
index a789acc..8477722 100644
--- a/firmware/control.c
+++ b/firmware/control.c
@@ -28,12 +28,6 @@ static pattern_t panic_pattern[] = {
 	PATTERN_END
 };
 
-static pattern_t brake_pattern [] = {
-	{ 4, D_2 },
-	{ 3, D_8 },
-	PATTERN_END
-};
-
 static pattern_t slow_pattern[] = {
 	{ PWM_PAT(1, 0, 0), D_1 },
 	{ PWM_PAT(0, 0, 1), D_1 },
@@ -70,7 +64,8 @@ pattern_t on_pattern[] = {
 	PATTERN_END
 };
 
-static unsigned char dim_mode, towbar_mode, braking;
+volatile unsigned char braking;
+static unsigned char dim_mode, towbar_mode;
 
 void init_control()
 {
@@ -84,7 +79,7 @@ void brake_on()
 	braking = 1;
 	gpio_set(0, 1);
 	led_set_pattern(N_STATUS_LED, status_led_pattern_select());
-	led_set_pattern(0, pwmled_pattern_select());
+	pwmleds_update_mode();
 }
 
 void brake_off()
@@ -92,7 +87,7 @@ void brake_off()
 	braking = 0;
 	gpio_set(0, 0);
 	led_set_pattern(N_STATUS_LED, status_led_pattern_select());
-	led_set_pattern(0, pwmled_pattern_select());
+	pwmleds_update_mode();
 }
 
 void toggle_dim_mode()
@@ -112,12 +107,6 @@ pattern_t *pwmled_pattern_select()
 	if (battery_critical)
 		return slow_pattern;
 
-	if (towbar_mode)
-		return NULL;
-
-	if (braking)
-		return brake_pattern;
-
 	switch (ambient_zone) {
 	case 0: return night_pattern;
 	case 1:
diff --git a/firmware/lights.h b/firmware/lights.h
index 26f7372..2c06b57 100644
--- a/firmware/lights.h
+++ b/firmware/lights.h
@@ -108,6 +108,7 @@ void patterns_next_tick();
 void led_set_pattern(unsigned char led, pattern_t *pattern);
 pattern_t *number_pattern(unsigned char num, unsigned char inv);
 void pattern_reload();
+void pwmleds_update_mode();
 
 /* buttons.c */
 #define MAX_USER_PARAMS 3
@@ -129,6 +130,7 @@ unsigned char battery_gauge();
 
 /* control.c */
 extern pattern_t on_pattern[];
+extern volatile unsigned char braking;
 
 void init_control();
 void brake_on();
diff --git a/firmware/pattern.c b/firmware/pattern.c
index ab63e34..c9f4ded 100644
--- a/firmware/pattern.c
+++ b/firmware/pattern.c
@@ -85,11 +85,41 @@ pattern_t off_pattern[] = {
 	PATTERN_END
 };
 
-static void inline pwmleds_set_mode(unsigned char mode)
+/*
+ * This is tricky: we use a single pattern for all three pwmleds,
+ * but on some occasions, we want to be able to modify only a single
+ * pwmled status without affecting other outputs. For example, during
+ * braking, we want to modify only the rear pwmled status. We don't
+ * use a separate "braking" pattern for every other pattern used, but instead
+ * we change the pwmled0 status regardless of the original value when
+ * braking. The rule is the following:
+ * - if during braking the pwmled2 (front) is at mode 2, we switch it to
+ *   mode 3 (which has the same target current) to avoid flicker.
+ * - if pwmled0 (rear) is off, we set it to mode 2
+ *   	(if it is with mode 1, we keep it at mode 1)
+ * TODO: something similar should be done for the "entering the dark area"
+ * 	condition, where we want to switch pwmled2 (front) on, to mode 2.
+ */
+void pwmleds_update_mode()
 {
-	pwmled_set_mode(0, mode & 3);
-	pwmled_set_mode(1, (mode >> 2) & 1);
-	pwmled_set_mode(2, (mode >> 3) & 3);
+	unsigned char mode, mode0, mode1, mode2;
+
+	mode = led_patterns[0]->mode;
+
+	mode0 = mode & 3;
+	mode1 = (mode >> 2) & 1;
+	mode2 = (mode >> 3) & 3;
+
+	if (braking) {
+		if (!mode0)
+			mode0 = 2;
+		if (mode2 == 2)
+			mode2 = 3;
+	}
+
+	pwmled_set_mode(0, mode0);
+	pwmled_set_mode(1, mode1);
+	pwmled_set_mode(2, mode2);
 }
 
 void led_set_pattern(unsigned char n, pattern_t *pattern)
@@ -102,7 +132,7 @@ void led_set_pattern(unsigned char n, pattern_t *pattern)
 	led_counters[n] = fibonacci[pattern->duration_fib];
 
 	if (n == 0) {
-		pwmleds_set_mode(pattern->mode);
+		pwmleds_update_mode();
 	} else if (n < N_LEDS) {
 		gpio_set(n - 1, pattern->mode);
 	}
-- 
2.39.3