diff options
Diffstat (limited to 'quantum/backlight/backlight_avr.c')
| -rw-r--r-- | quantum/backlight/backlight_avr.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/quantum/backlight/backlight_avr.c b/quantum/backlight/backlight_avr.c index b3e882ffe..4d66da80b 100644 --- a/quantum/backlight/backlight_avr.c +++ b/quantum/backlight/backlight_avr.c | |||
| @@ -3,6 +3,11 @@ | |||
| 3 | #include "backlight_driver_common.h" | 3 | #include "backlight_driver_common.h" |
| 4 | #include "debug.h" | 4 | #include "debug.h" |
| 5 | 5 | ||
| 6 | // Maximum duty cycle limit | ||
| 7 | #ifndef BACKLIGHT_LIMIT_VAL | ||
| 8 | # define BACKLIGHT_LIMIT_VAL 255 | ||
| 9 | #endif | ||
| 10 | |||
| 6 | // This logic is a bit complex, we support 3 setups: | 11 | // This logic is a bit complex, we support 3 setups: |
| 7 | // | 12 | // |
| 8 | // 1. Hardware PWM when backlight is wired to a PWM pin. | 13 | // 1. Hardware PWM when backlight is wired to a PWM pin. |
| @@ -240,6 +245,9 @@ static uint16_t cie_lightness(uint16_t v) { | |||
| 240 | } | 245 | } |
| 241 | } | 246 | } |
| 242 | 247 | ||
| 248 | // rescale the supplied backlight value to be in terms of the value limit | ||
| 249 | static uint32_t rescale_limit_val(uint32_t val) { return (val * (BACKLIGHT_LIMIT_VAL + 1)) / 256; } | ||
| 250 | |||
| 243 | // range for val is [0..TIMER_TOP]. PWM pin is high while the timer count is below val. | 251 | // range for val is [0..TIMER_TOP]. PWM pin is high while the timer count is below val. |
| 244 | static inline void set_pwm(uint16_t val) { OCRxx = val; } | 252 | static inline void set_pwm(uint16_t val) { OCRxx = val; } |
| 245 | 253 | ||
| @@ -269,7 +277,7 @@ void backlight_set(uint8_t level) { | |||
| 269 | #endif | 277 | #endif |
| 270 | } | 278 | } |
| 271 | // Set the brightness | 279 | // Set the brightness |
| 272 | set_pwm(cie_lightness(TIMER_TOP * (uint32_t)level / BACKLIGHT_LEVELS)); | 280 | set_pwm(cie_lightness(rescale_limit_val(TIMER_TOP * (uint32_t)level / BACKLIGHT_LEVELS))); |
| 273 | } | 281 | } |
| 274 | 282 | ||
| 275 | void backlight_task(void) {} | 283 | void backlight_task(void) {} |
| @@ -375,7 +383,7 @@ ISR(TIMERx_OVF_vect) | |||
| 375 | breathing_interrupt_disable(); | 383 | breathing_interrupt_disable(); |
| 376 | } | 384 | } |
| 377 | 385 | ||
| 378 | set_pwm(cie_lightness(scale_backlight((uint16_t)pgm_read_byte(&breathing_table[index]) * 0x0101U))); | 386 | set_pwm(cie_lightness(rescale_limit_val(scale_backlight((uint16_t)pgm_read_byte(&breathing_table[index]) * 0x0101U)))); |
| 379 | } | 387 | } |
| 380 | 388 | ||
| 381 | #endif // BACKLIGHT_BREATHING | 389 | #endif // BACKLIGHT_BREATHING |
