From f22a61e7e9588c212c258ffeb14c005379c66158 Mon Sep 17 00:00:00 2001 From: Nick Brassel Date: Mon, 7 Sep 2020 11:05:50 +1000 Subject: [PATCH] Rescale both ChibiOS and AVR backlighting. --- docs/feature_backlight.md | 17 +++++++++-------- quantum/backlight/backlight_avr.c | 14 ++++++++++++-- quantum/backlight/backlight_chibios.c | 14 ++++++++++++-- 3 files changed, 33 insertions(+), 12 deletions(-) diff --git a/docs/feature_backlight.md b/docs/feature_backlight.md index 6bb2bbed84..a558af64e1 100644 --- a/docs/feature_backlight.md +++ b/docs/feature_backlight.md @@ -62,14 +62,15 @@ Valid driver values are `pwm`, `software`, `custom` or `no`. See below for help To configure the backlighting, `#define` these in your `config.h`: -|Define |Default |Description | -|---------------------|-------------|-------------------------------------------------------------------------------------| -|`BACKLIGHT_PIN` |*Not defined*|The pin that controls the LED(s) | -|`BACKLIGHT_LEVELS` |`3` |The number of brightness levels (maximum 31 excluding off) | -|`BACKLIGHT_CAPS_LOCK`|*Not defined*|Enable Caps Lock indicator using backlight (for keyboards without dedicated LED) | -|`BACKLIGHT_BREATHING`|*Not defined*|Enable backlight breathing, if supported | -|`BREATHING_PERIOD` |`6` |The length of one backlight "breath" in seconds | -|`BACKLIGHT_ON_STATE` |`1` |The state of the backlight pin when the backlight is "on" - `1` for high, `0` for low| +| Define | Default | Description | +|------------------------|---------------|-------------------------------------------------------------------------------------------------------------------| +| `BACKLIGHT_PIN` | *Not defined* | The pin that controls the LED(s) | +| `BACKLIGHT_LEVELS` | `3` | The number of brightness levels (maximum 31 excluding off) | +| `BACKLIGHT_CAPS_LOCK` | *Not defined* | Enable Caps Lock indicator using backlight (for keyboards without dedicated LED) | +| `BACKLIGHT_BREATHING` | *Not defined* | Enable backlight breathing, if supported | +| `BREATHING_PERIOD` | `6` | The length of one backlight "breath" in seconds | +| `BACKLIGHT_ON_STATE` | `1` | The state of the backlight pin when the backlight is "on" - `1` for high, `0` for low | +| `BACKLIGHT_LIMIT_VAL ` | `255` | The maximum duty cycle of the backlight -- `255` allows for full brightness, any lower will decrease the maximum. | Unless you are designing your own keyboard, you generally should not need to change the `BACKLIGHT_PIN` or `BACKLIGHT_ON_STATE`. diff --git a/quantum/backlight/backlight_avr.c b/quantum/backlight/backlight_avr.c index b3e882ffe1..f5a3b59d2e 100644 --- a/quantum/backlight/backlight_avr.c +++ b/quantum/backlight/backlight_avr.c @@ -3,6 +3,11 @@ #include "backlight_driver_common.h" #include "debug.h" +// Maximum duty cycle limit +#ifndef BACKLIGHT_LIMIT_VAL +# define BACKLIGHT_LIMIT_VAL 255 +#endif + // This logic is a bit complex, we support 3 setups: // // 1. Hardware PWM when backlight is wired to a PWM pin. @@ -240,6 +245,11 @@ static uint16_t cie_lightness(uint16_t v) { } } +// rescale the supplied backlight value to be in terms of the value limit +static uint32_t rescale_limit_val(uint32_t val) { + return (val * (BACKLIGHT_LIMIT_VAL + 1)) / 256; +} + // 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; } @@ -269,7 +279,7 @@ void backlight_set(uint8_t level) { #endif } // Set the brightness - set_pwm(cie_lightness(TIMER_TOP * (uint32_t)level / BACKLIGHT_LEVELS)); + set_pwm(cie_lightness(rescale_limit_val(TIMER_TOP * (uint32_t)level / BACKLIGHT_LEVELS))); } void backlight_task(void) {} @@ -375,7 +385,7 @@ ISR(TIMERx_OVF_vect) breathing_interrupt_disable(); } - set_pwm(cie_lightness(scale_backlight((uint16_t)pgm_read_byte(&breathing_table[index]) * 0x0101U))); + set_pwm(cie_lightness(rescale_limit_val(scale_backlight((uint16_t)pgm_read_byte(&breathing_table[index]) * 0x0101U)))); } #endif // BACKLIGHT_BREATHING diff --git a/quantum/backlight/backlight_chibios.c b/quantum/backlight/backlight_chibios.c index 0fe812bf27..4d5a69e14e 100644 --- a/quantum/backlight/backlight_chibios.c +++ b/quantum/backlight/backlight_chibios.c @@ -3,6 +3,11 @@ #include #include "debug.h" +// Maximum duty cycle limit +#ifndef BACKLIGHT_LIMIT_VAL +# define BACKLIGHT_LIMIT_VAL 255 +#endif + // GPIOV2 && GPIOV3 #ifndef BACKLIGHT_PAL_MODE # define BACKLIGHT_PAL_MODE 2 @@ -58,6 +63,11 @@ static uint16_t cie_lightness(uint16_t v) { } } +static uint32_t rescale_limit_val(uint32_t val) { + // rescale the supplied backlight value to be in terms of the value limit + return (val * (BACKLIGHT_LIMIT_VAL + 1)) / 256; +} + void backlight_init_ports(void) { #ifdef USE_GPIOV1 palSetPadMode(PAL_PORT(BACKLIGHT_PIN), PAL_PAD(BACKLIGHT_PIN), PAL_MODE_STM32_ALTERNATE_PUSHPULL); @@ -85,7 +95,7 @@ void backlight_set(uint8_t level) { pwmDisableChannel(&BACKLIGHT_PWM_DRIVER, BACKLIGHT_PWM_CHANNEL - 1); } else { // Turn backlight on - uint32_t duty = (uint32_t)(cie_lightness(0xFFFF * (uint32_t)level / BACKLIGHT_LEVELS)); + uint32_t duty = (uint32_t)(cie_lightness(rescale_limit_val(0xFFFF * (uint32_t)level / BACKLIGHT_LEVELS))); pwmEnableChannel(&BACKLIGHT_PWM_DRIVER, BACKLIGHT_PWM_CHANNEL - 1, PWM_FRACTION_TO_WIDTH(&BACKLIGHT_PWM_DRIVER, 0xFFFF, duty)); } } @@ -129,7 +139,7 @@ void breathing_callback(PWMDriver *pwmp) { static uint16_t breathing_counter = 0; breathing_counter = (breathing_counter + 1) % (breathing_period * 256); uint8_t index = breathing_counter / interval % BREATHING_STEPS; - uint32_t duty = cie_lightness(scale_backlight(breathing_table[index] * 256)); + uint32_t duty = cie_lightness(rescale_limit_val(scale_backlight(breathing_table[index] * 256))); chSysLockFromISR(); pwmEnableChannelI(pwmp, BACKLIGHT_PWM_CHANNEL - 1, PWM_FRACTION_TO_WIDTH(&BACKLIGHT_PWM_DRIVER, 0xFFFF, duty));