diff options
Diffstat (limited to 'quantum/quantum.c')
| -rw-r--r-- | quantum/quantum.c | 256 |
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) {} |