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-rw-r--r--quantum/quantum.c256
1 files changed, 213 insertions, 43 deletions
diff --git a/quantum/quantum.c b/quantum/quantum.c
index 9aa498dadb..0fb798a748 100644
--- a/quantum/quantum.c
+++ b/quantum/quantum.c
@@ -1138,30 +1138,38 @@ void matrix_scan_quantum() {
matrix_scan_kb();
}
-#if defined(BACKLIGHT_ENABLE) && defined(BACKLIGHT_PIN)
+#if defined(BACKLIGHT_ENABLE) && (defined(BACKLIGHT_PIN) || defined(BACKLIGHT_PINS))
-static const uint8_t backlight_pin = BACKLIGHT_PIN;
+// The logic is a bit complex, we support 3 setups:
+// 1. hardware PWM when backlight is wired to a PWM pin
+// depending on this pin, we use a different output compare unit
+// 2. software PWM with hardware timers, but the used timer depends
+// on the audio setup (audio wins other backlight)
+// 3. full software PWM
-// depending on the pin, we use a different output compare unit
#if BACKLIGHT_PIN == B7
+# define HARDWARE_PWM
# define TCCRxA TCCR1A
# define TCCRxB TCCR1B
# define COMxx1 COM1C1
# define OCRxx OCR1C
# define ICRx ICR1
#elif BACKLIGHT_PIN == B6
+# define HARDWARE_PWM
# define TCCRxA TCCR1A
# define TCCRxB TCCR1B
# define COMxx1 COM1B1
# define OCRxx OCR1B
# define ICRx ICR1
#elif BACKLIGHT_PIN == B5
+# define HARDWARE_PWM
# define TCCRxA TCCR1A
# define TCCRxB TCCR1B
# define COMxx1 COM1A1
# define OCRxx OCR1A
# define ICRx ICR1
#elif BACKLIGHT_PIN == C6
+# define HARDWARE_PWM
# define TCCRxA TCCR3A
# define TCCRxB TCCR3B
# define COMxx1 COM1A1
@@ -1175,28 +1183,115 @@ static const uint8_t backlight_pin = BACKLIGHT_PIN;
# define ICRx ICR1
# define TIMSK1 TIMSK
#else
-# define NO_HARDWARE_PWM
+# if !defined(BACKLIGHT_CUSTOM_DRIVER)
+# if !defined(B5_AUDIO) && !defined(B6_AUDIO) && !defined(B7_AUDIO)
+ // timer 1 is not used by audio , backlight can use it
+#pragma message "Using hardware timer 1 with software PWM"
+# define HARDWARE_PWM
+# define BACKLIGHT_PWM_TIMER
+# define TCCRxA TCCR1A
+# define TCCRxB TCCR1B
+# define OCRxx OCR1A
+# define OCRxAH OCR1AH
+# define OCRxAL OCR1AL
+# define TIMERx_COMPA_vect TIMER1_COMPA_vect
+# define TIMERx_OVF_vect TIMER1_OVF_vect
+# define OCIExA OCIE1A
+# define TOIEx TOIE1
+# define ICRx ICR1
+# ifndef TIMSK
+# define TIMSK TIMSK1
+# endif
+# elif !defined(C6_AUDIO) && !defined(C5_AUDIO) && !defined(C4_AUDIO)
+#pragma message "Using hardware timer 3 with software PWM"
+// timer 3 is not used by audio, backlight can use it
+# define HARDWARE_PWM
+# define BACKLIGHT_PWM_TIMER
+# define TCCRxA TCCR3A
+# define TCCRxB TCCR3B
+# define OCRxx OCR3A
+# define OCRxAH OCR3AH
+# define OCRxAL OCR3AL
+# define TIMERx_COMPA_vect TIMER3_COMPA_vect
+# define TIMERx_OVF_vect TIMER3_OVF_vect
+# define OCIExA OCIE3A
+# define TOIEx TOIE3
+# define ICRx ICR1
+# ifndef TIMSK
+# define TIMSK TIMSK3
+# endif
+# else
+#pragma message "Audio in use - using pure software PWM"
+#define NO_HARDWARE_PWM
+# endif
+# else
+#pragma message "Custom driver defined - using pure software PWM"
+#define NO_HARDWARE_PWM
+# endif
#endif
#ifndef BACKLIGHT_ON_STATE
#define BACKLIGHT_ON_STATE 0
#endif
-#ifdef NO_HARDWARE_PWM // pwm through software
+void backlight_on(uint8_t backlight_pin) {
+#if BACKLIGHT_ON_STATE == 0
+ writePinLow(backlight_pin);
+#else
+ writePinHigh(backlight_pin);
+#endif
+}
-__attribute__ ((weak))
+void backlight_off(uint8_t backlight_pin) {
+#if BACKLIGHT_ON_STATE == 0
+ writePinHigh(backlight_pin);
+#else
+ writePinLow(backlight_pin);
+#endif
+}
+
+
+#if defined(NO_HARDWARE_PWM) || defined(BACKLIGHT_PWM_TIMER) // pwm through software
+
+// we support multiple backlight pins
+#ifndef BACKLIGHT_LED_COUNT
+#define BACKLIGHT_LED_COUNT 1
+#endif
+
+#if BACKLIGHT_LED_COUNT == 1
+#define BACKLIGHT_PIN_INIT { BACKLIGHT_PIN }
+#else
+#define BACKLIGHT_PIN_INIT BACKLIGHT_PINS
+#endif
+
+#define FOR_EACH_LED(x) \
+ for (uint8_t i = 0; i < BACKLIGHT_LED_COUNT; i++) \
+ { \
+ uint8_t backlight_pin = backlight_pins[i]; \
+ { \
+ x \
+ } \
+ }
+
+static const uint8_t backlight_pins[BACKLIGHT_LED_COUNT] = BACKLIGHT_PIN_INIT;
+
+#else // full hardware PWM
+
+// we support only one backlight pin
+static const uint8_t backlight_pin = BACKLIGHT_PIN;
+#define FOR_EACH_LED(x) x
+
+#endif
+
+#ifdef NO_HARDWARE_PWM
+__attribute__((weak))
void backlight_init_ports(void)
{
// Setup backlight pin as output and output to on state.
- // DDRx |= n
- _SFR_IO8((backlight_pin >> 4) + 1) |= _BV(backlight_pin & 0xF);
- #if BACKLIGHT_ON_STATE == 0
- // PORTx &= ~n
- _SFR_IO8((backlight_pin >> 4) + 2) &= ~_BV(backlight_pin & 0xF);
- #else
- // PORTx |= n
- _SFR_IO8((backlight_pin >> 4) + 2) |= _BV(backlight_pin & 0xF);
- #endif
+ FOR_EACH_LED(
+ setPinOutput(backlight_pin);
+ backlight_on(backlight_pin);
+ )
}
__attribute__ ((weak))
@@ -1207,21 +1302,14 @@ uint8_t backlight_tick = 0;
#ifndef BACKLIGHT_CUSTOM_DRIVER
void backlight_task(void) {
if ((0xFFFF >> ((BACKLIGHT_LEVELS - get_backlight_level()) * ((BACKLIGHT_LEVELS + 1) / 2))) & (1 << backlight_tick)) {
- #if BACKLIGHT_ON_STATE == 0
- // PORTx &= ~n
- _SFR_IO8((backlight_pin >> 4) + 2) &= ~_BV(backlight_pin & 0xF);
- #else
- // PORTx |= n
- _SFR_IO8((backlight_pin >> 4) + 2) |= _BV(backlight_pin & 0xF);
- #endif
- } else {
- #if BACKLIGHT_ON_STATE == 0
- // PORTx |= n
- _SFR_IO8((backlight_pin >> 4) + 2) |= _BV(backlight_pin & 0xF);
- #else
- // PORTx &= ~n
- _SFR_IO8((backlight_pin >> 4) + 2) &= ~_BV(backlight_pin & 0xF);
- #endif
+ FOR_EACH_LED(
+ backlight_on(backlight_pin);
+ )
+ }
+ else {
+ FOR_EACH_LED(
+ backlight_off(backlight_pin);
+ )
}
backlight_tick = (backlight_tick + 1) % 16;
}
@@ -1233,7 +1321,52 @@ void backlight_task(void) {
#endif
#endif
-#else // pwm through timer
+#else // hardware pwm through timer
+
+#ifdef BACKLIGHT_PWM_TIMER
+
+// The idea of software PWM assisted by hardware timers is the following
+// we use the hardware timer in fast PWM mode like for hardware PWM, but
+// instead of letting the Output Match Comparator control the led pin
+// (which is not possible since the backlight is not wired to PWM pins on the
+// CPU), we do the LED on/off by oursleves.
+// The timer is setup to count up to 0xFFFF, and we set the Output Compare
+// register to the current 16bits backlight level (after CIE correction).
+// This means the CPU will trigger a compare match interrupt when the counter
+// reaches the backlight level, where we turn off the LEDs,
+// but also an overflow interrupt when the counter rolls back to 0,
+// in which we're going to turn on the LEDs.
+// The LED will then be on for OCRxx/0xFFFF time, adjusted every 244Hz.
+
+// Triggered when the counter reaches the OCRx value
+ISR(TIMERx_COMPA_vect) {
+ FOR_EACH_LED(
+ backlight_off(backlight_pin);
+ )
+}
+
+// Triggered when the counter reaches the TOP value
+// this one triggers at F_CPU/65536 =~ 244 Hz
+ISR(TIMERx_OVF_vect) {
+#ifdef BACKLIGHT_BREATHING
+ breathing_task();
+#endif
+ // for very small values of OCRxx (or backlight level)
+ // we can't guarantee this whole code won't execute
+ // at the same time as the compare match interrupt
+ // which means that we might turn on the leds while
+ // trying to turn them off, leading to flickering
+ // artifacts (especially while breathing, because breathing_task
+ // takes many computation cycles).
+ // so better not turn them on while the counter TOP is very low.
+ if (OCRxx > 256) {
+ FOR_EACH_LED(
+ backlight_on(backlight_pin);
+ )
+ }
+}
+
+#endif
#define TIMER_TOP 0xFFFFU
@@ -1265,11 +1398,28 @@ void backlight_set(uint8_t level) {
level = BACKLIGHT_LEVELS;
if (level == 0) {
+ #ifdef BACKLIGHT_PWM_TIMER
+ if (OCRxx) {
+ TIMSK &= ~(_BV(OCIExA));
+ TIMSK &= ~(_BV(TOIEx));
+ FOR_EACH_LED(
+ backlight_off(backlight_pin);
+ )
+ }
+ #else
// Turn off PWM control on backlight pin
TCCRxA &= ~(_BV(COMxx1));
+ #endif
} else {
+ #ifdef BACKLIGHT_PWM_TIMER
+ if (!OCRxx) {
+ TIMSK |= _BV(OCIExA);
+ TIMSK |= _BV(TOIEx);
+ }
+ #else
// Turn on PWM control of backlight pin
TCCRxA |= _BV(COMxx1);
+ #endif
}
// Set the brightness
set_pwm(cie_lightness(TIMER_TOP * (uint32_t)level / BACKLIGHT_LEVELS));
@@ -1289,12 +1439,25 @@ static uint8_t breathing_period = BREATHING_PERIOD;
static uint8_t breathing_halt = BREATHING_NO_HALT;
static uint16_t breathing_counter = 0;
+#ifdef BACKLIGHT_PWM_TIMER
+static bool breathing = false;
+
+bool is_breathing(void) {
+ return breathing;
+}
+
+#define breathing_interrupt_enable() do { breathing = true; } while (0)
+#define breathing_interrupt_disable() do { breathing = false; } while (0)
+#else
+
bool is_breathing(void) {
return !!(TIMSK1 & _BV(TOIE1));
}
#define breathing_interrupt_enable() do {TIMSK1 |= _BV(TOIE1);} while (0)
#define breathing_interrupt_disable() do {TIMSK1 &= ~_BV(TOIE1);} while (0)
+#endif
+
#define breathing_min() do {breathing_counter = 0;} while (0)
#define breathing_max() do {breathing_counter = breathing_period * 244 / 2;} while (0)
@@ -1368,10 +1531,14 @@ static inline uint16_t scale_backlight(uint16_t v) {
return v / BACKLIGHT_LEVELS * get_backlight_level();
}
+#ifdef BACKLIGHT_PWM_TIMER
+void breathing_task(void)
+#else
/* Assuming a 16MHz CPU clock and a timer that resets at 64k (ICR1), the following interrupt handler will run
* about 244 times per second.
*/
ISR(TIMER1_OVF_vect)
+#endif
{
uint16_t interval = (uint16_t) breathing_period * 244 / BREATHING_STEPS;
// resetting after one period to prevent ugly reset at overflow.
@@ -1393,19 +1560,21 @@ __attribute__ ((weak))
void backlight_init_ports(void)
{
// Setup backlight pin as output and output to on state.
- // DDRx |= n
- _SFR_IO8((backlight_pin >> 4) + 1) |= _BV(backlight_pin & 0xF);
- #if BACKLIGHT_ON_STATE == 0
- // PORTx &= ~n
- _SFR_IO8((backlight_pin >> 4) + 2) &= ~_BV(backlight_pin & 0xF);
- #else
- // PORTx |= n
- _SFR_IO8((backlight_pin >> 4) + 2) |= _BV(backlight_pin & 0xF);
- #endif
+ FOR_EACH_LED(
+ setPinOutput(backlight_pin);
+ backlight_on(backlight_pin);
+ )
+
// I could write a wall of text here to explain... but TL;DW
// Go read the ATmega32u4 datasheet.
// And this: http://blog.saikoled.com/post/43165849837/secret-konami-cheat-code-to-high-resolution-pwm-on
+#ifdef BACKLIGHT_PWM_TIMER
+ // TimerX setup, Fast PWM mode count to TOP set in ICRx
+ TCCRxA = _BV(WGM11); // = 0b00000010;
+ // clock select clk/1
+ TCCRxB = _BV(WGM13) | _BV(WGM12) | _BV(CS10); // = 0b00011001;
+#else // hardware PWM
// Pin PB7 = OCR1C (Timer 1, Channel C)
// Compare Output Mode = Clear on compare match, Channel C = COM1C1=1 COM1C0=0
// (i.e. start high, go low when counter matches.)
@@ -1417,8 +1586,9 @@ void backlight_init_ports(void)
"In fast PWM mode, the compare units allow generation of PWM waveforms on the OCnx pins. Setting the COMnx1:0 bits to two will produce a non-inverted PWM [..]."
"In fast PWM mode the counter is incremented until the counter value matches either one of the fixed values 0x00FF, 0x01FF, or 0x03FF (WGMn3:0 = 5, 6, or 7), the value in ICRn (WGMn3:0 = 14), or the value in OCRnA (WGMn3:0 = 15)."
*/
- TCCRxA = _BV(COMxx1) | _BV(WGM11); // = 0b00001010;
+ TCCRxA = _BV(COMxx1) | _BV(WGM11); // = 0b00001010;
TCCRxB = _BV(WGM13) | _BV(WGM12) | _BV(CS10); // = 0b00011001;
+#endif
// Use full 16-bit resolution. Counter counts to ICR1 before reset to 0.
ICRx = TIMER_TOP;
@@ -1428,9 +1598,9 @@ void backlight_init_ports(void)
#endif
}
-#endif // NO_HARDWARE_PWM
+#endif // hardware backlight
-#else // backlight
+#else // no backlight
__attribute__ ((weak))
void backlight_init_ports(void) {}