ARM - Initial backlight support (#6487)

* Move AVR backlight to own file, add borrowed ARM implementation

* Tiny fix for backlight custom logic

* Remove duplicate board from rebase

* Fix f303 onekey example

* clang-format

* clang-format

* Remove backlight keymap debug

* Initial pass of ARM backlight docs

* Initial pass of ARM backlight docs - resolve todos

* fix rules validation logic

* Add f072 warning

* Add f072 warning

* tidy up breathing in backlight keymap

* tidy up breathing in backlight keymap

* add missing break to backlight keymap

1 files changed, 0 insertions, 509 deletions

diff --git a/quantum/quantum.c b/quantum/quantum.c
index 16922dd011..f4999456e3 100644
--- a/quantum/quantum.c
+++ b/quantum/quantum.c
@@ -24,10 +24,6 @@
 #    include "outputselect.h"
 #endif
 
-#ifndef BREATHING_PERIOD
-#    define BREATHING_PERIOD 6
-#endif
-
 #include "backlight.h"
 extern backlight_config_t backlight_config;
 
@@ -1019,511 +1015,6 @@ void matrix_scan_quantum() {
 
     matrix_scan_kb();
 }
-#if defined(BACKLIGHT_ENABLE) && (defined(BACKLIGHT_PIN) || defined(BACKLIGHT_PINS))
-
-// This 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 over Backlight).
-//   3. Full software PWM, driven by the matrix scan, if both timers are used by Audio.
-
-#    if (defined(__AVR_AT90USB646__) || defined(__AVR_AT90USB647__) || defined(__AVR_AT90USB1286__) || defined(__AVR_AT90USB1287__) || defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__)) && (BACKLIGHT_PIN == B5 || BACKLIGHT_PIN == B6 || BACKLIGHT_PIN == B7)
-#        define HARDWARE_PWM
-#        define ICRx ICR1
-#        define TCCRxA TCCR1A
-#        define TCCRxB TCCR1B
-#        define TIMERx_OVF_vect TIMER1_OVF_vect
-#        define TIMSKx TIMSK1
-#        define TOIEx TOIE1
-
-#        if BACKLIGHT_PIN == B5
-#            define COMxx1 COM1A1
-#            define OCRxx OCR1A
-#        elif BACKLIGHT_PIN == B6
-#            define COMxx1 COM1B1
-#            define OCRxx OCR1B
-#        elif BACKLIGHT_PIN == B7
-#            define COMxx1 COM1C1
-#            define OCRxx OCR1C
-#        endif
-#    elif (defined(__AVR_AT90USB646__) || defined(__AVR_AT90USB647__) || defined(__AVR_AT90USB1286__) || defined(__AVR_AT90USB1287__) || defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__)) && (BACKLIGHT_PIN == C4 || BACKLIGHT_PIN == C5 || BACKLIGHT_PIN == C6)
-#        define HARDWARE_PWM
-#        define ICRx ICR3
-#        define TCCRxA TCCR3A
-#        define TCCRxB TCCR3B
-#        define TIMERx_OVF_vect TIMER3_OVF_vect
-#        define TIMSKx TIMSK3
-#        define TOIEx TOIE3
-
-#        if BACKLIGHT_PIN == C4
-#            if (defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__))
-#                error This MCU has no C4 pin!
-#            else
-#                define COMxx1 COM3C1
-#                define OCRxx OCR3C
-#            endif
-#        elif BACKLIGHT_PIN == C5
-#            if (defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__))
-#                error This MCU has no C5 pin!
-#            else
-#                define COMxx1 COM3B1
-#                define OCRxx OCR3B
-#            endif
-#        elif BACKLIGHT_PIN == C6
-#            define COMxx1 COM3A1
-#            define OCRxx OCR3A
-#        endif
-#    elif (defined(__AVR_ATmega16U2__) || defined(__AVR_ATmega32U2__)) && (BACKLIGHT_PIN == B7 || BACKLIGHT_PIN == C5 || BACKLIGHT_PIN == C6)
-#        define HARDWARE_PWM
-#        define ICRx ICR1
-#        define TCCRxA TCCR1A
-#        define TCCRxB TCCR1B
-#        define TIMERx_OVF_vect TIMER1_OVF_vect
-#        define TIMSKx TIMSK1
-#        define TOIEx TOIE1
-
-#        if BACKLIGHT_PIN == B7
-#            define COMxx1 COM1C1
-#            define OCRxx OCR1C
-#        elif BACKLIGHT_PIN == C5
-#            define COMxx1 COM1B1
-#            define OCRxx OCR1B
-#        elif BACKLIGHT_PIN == C6
-#            define COMxx1 COM1A1
-#            define OCRxx OCR1A
-#        endif
-#    elif defined(__AVR_ATmega32A__) && (BACKLIGHT_PIN == D4 || BACKLIGHT_PIN == D5)
-#        define HARDWARE_PWM
-#        define ICRx ICR1
-#        define TCCRxA TCCR1A
-#        define TCCRxB TCCR1B
-#        define TIMERx_OVF_vect TIMER1_OVF_vect
-#        define TIMSKx TIMSK
-#        define TOIEx TOIE1
-
-#        if BACKLIGHT_PIN == D4
-#            define COMxx1 COM1B1
-#            define OCRxx OCR1B
-#        elif BACKLIGHT_PIN == D5
-#            define COMxx1 COM1A1
-#            define OCRxx OCR1A
-#        endif
-#    elif defined(__AVR_ATmega328P__) && (BACKLIGHT_PIN == B1 || BACKLIGHT_PIN == B2)
-#        define HARDWARE_PWM
-#        define ICRx ICR1
-#        define TCCRxA TCCR1A
-#        define TCCRxB TCCR1B
-#        define TIMERx_OVF_vect TIMER1_OVF_vect
-#        define TIMSKx TIMSK1
-#        define TOIEx TOIE1
-
-#        if BACKLIGHT_PIN == B1
-#            define COMxx1 COM1A1
-#            define OCRxx OCR1A
-#        elif BACKLIGHT_PIN == B2
-#            define COMxx1 COM1B1
-#            define OCRxx OCR1B
-#        endif
-#    else
-#        if !defined(BACKLIGHT_CUSTOM_DRIVER)
-#            if !defined(B5_AUDIO) && !defined(B6_AUDIO) && !defined(B7_AUDIO)
-// Timer 1 is not in use by Audio feature, Backlight can use it
-#                pragma message "Using hardware timer 1 with software PWM"
-#                define HARDWARE_PWM
-#                define BACKLIGHT_PWM_TIMER
-#                define ICRx ICR1
-#                define TCCRxA TCCR1A
-#                define TCCRxB TCCR1B
-#                define TIMERx_COMPA_vect TIMER1_COMPA_vect
-#                define TIMERx_OVF_vect TIMER1_OVF_vect
-#                if defined(__AVR_ATmega32A__)  // This MCU has only one TIMSK register
-#                    define TIMSKx TIMSK
-#                else
-#                    define TIMSKx TIMSK1
-#                endif
-#                define TOIEx TOIE1
-
-#                define OCIExA OCIE1A
-#                define OCRxx OCR1A
-#            elif !defined(C6_AUDIO) && !defined(C5_AUDIO) && !defined(C4_AUDIO)
-#                pragma message "Using hardware timer 3 with software PWM"
-// Timer 3 is not in use by Audio feature, Backlight can use it
-#                define HARDWARE_PWM
-#                define BACKLIGHT_PWM_TIMER
-#                define ICRx ICR1
-#                define TCCRxA TCCR3A
-#                define TCCRxB TCCR3B
-#                define TIMERx_COMPA_vect TIMER3_COMPA_vect
-#                define TIMERx_OVF_vect TIMER3_OVF_vect
-#                define TIMSKx TIMSK3
-#                define TOIEx TOIE3
-
-#                define OCIExA OCIE3A
-#                define OCRxx OCR3A
-#            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
-
-void backlight_on(uint8_t backlight_pin) {
-#    if BACKLIGHT_ON_STATE == 0
-    writePinLow(backlight_pin);
-#    else
-    writePinHigh(backlight_pin);
-#    endif
-}
-
-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.
-    FOR_EACH_LED(setPinOutput(backlight_pin); backlight_on(backlight_pin);)
-
-#        ifdef BACKLIGHT_BREATHING
-    if (is_backlight_breathing()) {
-        breathing_enable();
-    }
-#        endif
-}
-
-__attribute__((weak)) void backlight_set(uint8_t level) {}
-
-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)) {
-        FOR_EACH_LED(backlight_on(backlight_pin);)
-    } else {
-        FOR_EACH_LED(backlight_off(backlight_pin);)
-    }
-    backlight_tick = (backlight_tick + 1) % 16;
-}
-#        endif
-
-#        ifdef BACKLIGHT_BREATHING
-#            ifndef BACKLIGHT_CUSTOM_DRIVER
-#                error "Backlight breathing only available with hardware PWM. Please disable."
-#            endif
-#        endif
-
-#    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
-    if (is_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
-
-// See http://jared.geek.nz/2013/feb/linear-led-pwm
-static uint16_t cie_lightness(uint16_t v) {
-    if (v <= 5243)     // if below 8% of max
-        return v / 9;  // same as dividing by 900%
-    else {
-        uint32_t y = (((uint32_t)v + 10486) << 8) / (10486 + 0xFFFFUL);  // add 16% of max and compare
-        // to get a useful result with integer division, we shift left in the expression above
-        // and revert what we've done again after squaring.
-        y = y * y * y >> 8;
-        if (y > 0xFFFFUL)  // prevent overflow
-            return 0xFFFFU;
-        else
-            return (uint16_t)y;
-    }
-}
-
-// range for val is [0..TIMER_TOP]. PWM pin is high while the timer count is below val.
-static inline void set_pwm(uint16_t val) { OCRxx = val; }
-
-#        ifndef BACKLIGHT_CUSTOM_DRIVER
-__attribute__((weak)) void backlight_set(uint8_t level) {
-    if (level > BACKLIGHT_LEVELS) level = BACKLIGHT_LEVELS;
-
-    if (level == 0) {
-#            ifdef BACKLIGHT_PWM_TIMER
-        if (OCRxx) {
-            TIMSKx &= ~(_BV(OCIExA));
-            TIMSKx &= ~(_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) {
-            TIMSKx |= _BV(OCIExA);
-            TIMSKx |= _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));
-}
-
-void backlight_task(void) {}
-#        endif  // BACKLIGHT_CUSTOM_DRIVER
-
-#        ifdef BACKLIGHT_BREATHING
-
-#            define BREATHING_NO_HALT 0
-#            define BREATHING_HALT_OFF 1
-#            define BREATHING_HALT_ON 2
-#            define BREATHING_STEPS 128
-
-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 !!(TIMSKx & _BV(TOIEx)); }
-
-#                define breathing_interrupt_enable() \
-                    do {                             \
-                        TIMSKx |= _BV(TOIEx);        \
-                    } while (0)
-#                define breathing_interrupt_disable() \
-                    do {                              \
-                        TIMSKx &= ~_BV(TOIEx);        \
-                    } while (0)
-#            endif
-
-#            define breathing_min()        \
-                do {                       \
-                    breathing_counter = 0; \
-                } while (0)
-#            define breathing_max()                                 \
-                do {                                                \
-                    breathing_counter = breathing_period * 244 / 2; \
-                } while (0)
-
-void breathing_enable(void) {
-    breathing_counter = 0;
-    breathing_halt = BREATHING_NO_HALT;
-    breathing_interrupt_enable();
-}
-
-void breathing_pulse(void) {
-    if (get_backlight_level() == 0)
-        breathing_min();
-    else
-        breathing_max();
-    breathing_halt = BREATHING_HALT_ON;
-    breathing_interrupt_enable();
-}
-
-void breathing_disable(void) {
-    breathing_interrupt_disable();
-    // Restore backlight level
-    backlight_set(get_backlight_level());
-}
-
-void breathing_self_disable(void) {
-    if (get_backlight_level() == 0)
-        breathing_halt = BREATHING_HALT_OFF;
-    else
-        breathing_halt = BREATHING_HALT_ON;
-}
-
-void breathing_toggle(void) {
-    if (is_breathing())
-        breathing_disable();
-    else
-        breathing_enable();
-}
-
-void breathing_period_set(uint8_t value) {
-    if (!value) value = 1;
-    breathing_period = value;
-}
-
-void breathing_period_default(void) { breathing_period_set(BREATHING_PERIOD); }
-
-void breathing_period_inc(void) { breathing_period_set(breathing_period + 1); }
-
-void breathing_period_dec(void) { breathing_period_set(breathing_period - 1); }
-
-/* To generate breathing curve in python:
- * from math import sin, pi; [int(sin(x/128.0*pi)**4*255) for x in range(128)]
- */
-static const uint8_t breathing_table[BREATHING_STEPS] PROGMEM = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 17, 20, 24, 28, 32, 36, 41, 46, 51, 57, 63, 70, 76, 83, 91, 98, 106, 113, 121, 129, 138, 146, 154, 162, 170, 178, 185, 193, 200, 207, 213, 220, 225, 231, 235, 240, 244, 247, 250, 252, 253, 254, 255, 254, 253, 252, 250, 247, 244, 240, 235, 231, 225, 220, 213, 207, 200, 193, 185, 178, 170, 162, 154, 146, 138, 129, 121, 113, 106, 98, 91, 83, 76, 70, 63, 57, 51, 46, 41, 36, 32, 28, 24, 20, 17, 15, 12, 10, 8, 6, 5, 4, 3, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
-
-// Use this before the cie_lightness function.
-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(TIMERx_OVF_vect)
-#            endif
-{
-    uint16_t interval = (uint16_t)breathing_period * 244 / BREATHING_STEPS;
-    // resetting after one period to prevent ugly reset at overflow.
-    breathing_counter = (breathing_counter + 1) % (breathing_period * 244);
-    uint8_t index = breathing_counter / interval % BREATHING_STEPS;
-
-    if (((breathing_halt == BREATHING_HALT_ON) && (index == BREATHING_STEPS / 2)) || ((breathing_halt == BREATHING_HALT_OFF) && (index == BREATHING_STEPS - 1))) {
-        breathing_interrupt_disable();
-    }
-
-    set_pwm(cie_lightness(scale_backlight((uint16_t)pgm_read_byte(&breathing_table[index]) * 0x0101U)));
-}
-
-#        endif  // BACKLIGHT_BREATHING
-
-__attribute__((weak)) void backlight_init_ports(void) {
-    // Setup backlight pin as output and output to on state.
-    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.)
-    // WGM Mode 14 (Fast PWM) = WGM13=1 WGM12=1 WGM11=1 WGM10=0
-    // Clock Select = clk/1 (no prescaling) = CS12=0 CS11=0 CS10=1
-
-    /*
-    14.8.3:
-    "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;
-    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;
-
-    backlight_init();
-#        ifdef BACKLIGHT_BREATHING
-    if (is_backlight_breathing()) {
-        breathing_enable();
-    }
-#        endif
-}
-
-#    endif  // hardware backlight
-
-#else  // no backlight
-
-__attribute__((weak)) void backlight_init_ports(void) {}
-
-__attribute__((weak)) void backlight_set(uint8_t level) {}
-
-#endif  // backlight
 
 #ifdef HD44780_ENABLED
 #    include "hd44780.h"