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-rw-r--r--quantum/backlight/backlight.c1
-rw-r--r--quantum/backlight/backlight_arm.c218
-rw-r--r--quantum/backlight/backlight_avr.c509
3 files changed, 728 insertions, 0 deletions
diff --git a/quantum/backlight/backlight.c b/quantum/backlight/backlight.c
new file mode 100644
index 000000000..e26de86bf
--- /dev/null
+++ b/quantum/backlight/backlight.c
@@ -0,0 +1 @@
// TODO: Add common code here, for example cie_lightness implementation
diff --git a/quantum/backlight/backlight_arm.c b/quantum/backlight/backlight_arm.c
new file mode 100644
index 000000000..3f94ccef8
--- /dev/null
+++ b/quantum/backlight/backlight_arm.c
@@ -0,0 +1,218 @@
1#include "quantum.h"
2#include "backlight.h"
3#include <hal.h>
4#include "debug.h"
5
6// TODO: remove short term bodge when refactoring BACKLIGHT_CUSTOM_DRIVER out
7#ifdef BACKLIGHT_PIN
8
9# if defined(STM32F0XX) || defined(STM32F0xx)
10# error "Backlight support for STMF072 is not available. Please disable."
11# endif
12
13# if defined(STM32F1XX) || defined(STM32F1xx)
14# define USE_GPIOV1
15# endif
16
17// GPIOV2 && GPIOV3
18# ifndef BACKLIGHT_PAL_MODE
19# define BACKLIGHT_PAL_MODE 2
20# endif
21
22// GENERIC
23# ifndef BACKLIGHT_PWM_DRIVER
24# define BACKLIGHT_PWM_DRIVER PWMD4
25# endif
26# ifndef BACKLIGHT_PWM_CHANNEL
27# define BACKLIGHT_PWM_CHANNEL 3
28# endif
29
30static void breathing_callback(PWMDriver *pwmp);
31
32static PWMConfig pwmCFG = {0xFFFF, /* PWM clock frequency */
33 256, /* PWM period (in ticks) 1S (1/10kHz=0.1mS 0.1ms*10000 ticks=1S) */
34 NULL, /* No Callback */
35 { /* Default all channels to disabled - Channels will be configured durring init */
36 {PWM_OUTPUT_DISABLED, NULL},
37 {PWM_OUTPUT_DISABLED, NULL},
38 {PWM_OUTPUT_DISABLED, NULL},
39 {PWM_OUTPUT_DISABLED, NULL}},
40 0, /* HW dependent part.*/
41 0};
42
43static PWMConfig pwmCFG_breathing = {0xFFFF, /** PWM clock frequency */
44 256, /* PWM period (in ticks) 1S (1/10kHz=0.1mS 0.1ms*10000 ticks=1S) */
45 breathing_callback, /* Breathing Callback */
46 { /* Default all channels to disabled - Channels will be configured durring init */
47 {PWM_OUTPUT_DISABLED, NULL},
48 {PWM_OUTPUT_DISABLED, NULL},
49 {PWM_OUTPUT_DISABLED, NULL},
50 {PWM_OUTPUT_DISABLED, NULL}},
51 0, /* HW dependent part.*/
52 0};
53
54// See http://jared.geek.nz/2013/feb/linear-led-pwm
55static uint16_t cie_lightness(uint16_t v) {
56 if (v <= 5243) // if below 8% of max
57 return v / 9; // same as dividing by 900%
58 else {
59 uint32_t y = (((uint32_t)v + 10486) << 8) / (10486 + 0xFFFFUL); // add 16% of max and compare
60 // to get a useful result with integer division, we shift left in the expression above
61 // and revert what we've done again after squaring.
62 y = y * y * y >> 8;
63 if (y > 0xFFFFUL) // prevent overflow
64 return 0xFFFFU;
65 else
66 return (uint16_t)y;
67 }
68}
69
70void backlight_init_ports(void) {
71 // printf("backlight_init_ports()\n");
72
73# ifdef USE_GPIOV1
74 palSetPadMode(PAL_PORT(BACKLIGHT_PIN), PAL_PAD(BACKLIGHT_PIN), PAL_MODE_STM32_ALTERNATE_PUSHPULL);
75# else
76 palSetPadMode(PAL_PORT(BACKLIGHT_PIN), PAL_PAD(BACKLIGHT_PIN), PAL_MODE_ALTERNATE(BACKLIGHT_PAL_MODE));
77# endif
78
79 pwmCFG.channels[BACKLIGHT_PWM_CHANNEL - 1].mode = PWM_OUTPUT_ACTIVE_HIGH;
80 pwmCFG_breathing.channels[BACKLIGHT_PWM_CHANNEL - 1].mode = PWM_OUTPUT_ACTIVE_HIGH;
81 pwmStart(&BACKLIGHT_PWM_DRIVER, &pwmCFG);
82
83 backlight_set(get_backlight_level());
84 if (is_backlight_breathing()) {
85 breathing_enable();
86 }
87}
88
89void backlight_set(uint8_t level) {
90 // printf("backlight_set(%d)\n", level);
91 if (level == 0) {
92 // Turn backlight off
93 pwmDisableChannel(&BACKLIGHT_PWM_DRIVER, BACKLIGHT_PWM_CHANNEL - 1);
94 } else {
95 // Turn backlight on
96 if (!is_breathing()) {
97 uint32_t duty = (uint32_t)(cie_lightness(0xFFFF * (uint32_t)level / BACKLIGHT_LEVELS));
98 // printf("duty: (%d)\n", duty);
99 pwmEnableChannel(&BACKLIGHT_PWM_DRIVER, BACKLIGHT_PWM_CHANNEL - 1, PWM_FRACTION_TO_WIDTH(&BACKLIGHT_PWM_DRIVER, 0xFFFF, duty));
100 }
101 }
102}
103
104uint8_t backlight_tick = 0;
105
106void backlight_task(void) {}
107
108# define BREATHING_NO_HALT 0
109# define BREATHING_HALT_OFF 1
110# define BREATHING_HALT_ON 2
111# define BREATHING_STEPS 128
112
113static uint8_t breathing_period = BREATHING_PERIOD;
114static uint8_t breathing_halt = BREATHING_NO_HALT;
115static uint16_t breathing_counter = 0;
116
117bool is_breathing(void) { return BACKLIGHT_PWM_DRIVER.config == &pwmCFG_breathing; }
118
119static inline void breathing_min(void) { breathing_counter = 0; }
120
121static inline void breathing_max(void) { breathing_counter = breathing_period * 256 / 2; }
122
123void breathing_interrupt_enable(void) {
124 pwmStop(&BACKLIGHT_PWM_DRIVER);
125 pwmStart(&BACKLIGHT_PWM_DRIVER, &pwmCFG_breathing);
126 chSysLockFromISR();
127 pwmEnablePeriodicNotification(&BACKLIGHT_PWM_DRIVER);
128 pwmEnableChannelI(&BACKLIGHT_PWM_DRIVER, BACKLIGHT_PWM_CHANNEL - 1, PWM_FRACTION_TO_WIDTH(&BACKLIGHT_PWM_DRIVER, 0xFFFF, 0xFFFF));
129 chSysUnlockFromISR();
130}
131
132void breathing_interrupt_disable(void) {
133 pwmStop(&BACKLIGHT_PWM_DRIVER);
134 pwmStart(&BACKLIGHT_PWM_DRIVER, &pwmCFG);
135}
136
137void breathing_enable(void) {
138 breathing_counter = 0;
139 breathing_halt = BREATHING_NO_HALT;
140 breathing_interrupt_enable();
141}
142
143void breathing_pulse(void) {
144 if (get_backlight_level() == 0)
145 breathing_min();
146 else
147 breathing_max();
148 breathing_halt = BREATHING_HALT_ON;
149 breathing_interrupt_enable();
150}
151
152void breathing_disable(void) {
153 // printf("breathing_disable()\n");
154 breathing_interrupt_disable();
155 // Restore backlight level
156 backlight_set(get_backlight_level());
157}
158
159void breathing_self_disable(void) {
160 if (get_backlight_level() == 0)
161 breathing_halt = BREATHING_HALT_OFF;
162 else
163 breathing_halt = BREATHING_HALT_ON;
164}
165
166void breathing_toggle(void) {
167 if (is_breathing())
168 breathing_disable();
169 else
170 breathing_enable();
171}
172
173void breathing_period_set(uint8_t value) {
174 if (!value) value = 1;
175 breathing_period = value;
176}
177
178void breathing_period_default(void) { breathing_period_set(BREATHING_PERIOD); }
179
180void breathing_period_inc(void) { breathing_period_set(breathing_period + 1); }
181
182void breathing_period_dec(void) { breathing_period_set(breathing_period - 1); }
183
184/* To generate breathing curve in python:
185 * from math import sin, pi; [int(sin(x/128.0*pi)**4*255) for x in range(128)]
186 */
187static const uint8_t breathing_table[BREATHING_STEPS] = {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};
188
189// Use this before the cie_lightness function.
190static inline uint16_t scale_backlight(uint16_t v) { return v / BACKLIGHT_LEVELS * get_backlight_level(); }
191
192static void breathing_callback(PWMDriver *pwmp) {
193 (void)pwmp;
194 uint16_t interval = (uint16_t)breathing_period * 256 / BREATHING_STEPS;
195 // resetting after one period to prevent ugly reset at overflow.
196 breathing_counter = (breathing_counter + 1) % (breathing_period * 256);
197 uint8_t index = breathing_counter / interval % BREATHING_STEPS;
198
199 if (((breathing_halt == BREATHING_HALT_ON) && (index == BREATHING_STEPS / 2)) || ((breathing_halt == BREATHING_HALT_OFF) && (index == BREATHING_STEPS - 1))) {
200 breathing_interrupt_disable();
201 }
202
203 uint32_t duty = cie_lightness(scale_backlight(breathing_table[index] * 256));
204
205 chSysLockFromISR();
206 pwmEnableChannelI(&BACKLIGHT_PWM_DRIVER, BACKLIGHT_PWM_CHANNEL - 1, PWM_FRACTION_TO_WIDTH(&BACKLIGHT_PWM_DRIVER, 0xFFFF, duty));
207 chSysUnlockFromISR();
208}
209
210#else
211
212__attribute__((weak)) void backlight_init_ports(void) {}
213
214__attribute__((weak)) void backlight_set(uint8_t level) {}
215
216__attribute__((weak)) void backlight_task(void) {}
217
218#endif
diff --git a/quantum/backlight/backlight_avr.c b/quantum/backlight/backlight_avr.c
new file mode 100644
index 000000000..445698f47
--- /dev/null
+++ b/quantum/backlight/backlight_avr.c
@@ -0,0 +1,509 @@
1#include "quantum.h"
2#include "backlight.h"
3#include "debug.h"
4
5#if defined(BACKLIGHT_ENABLE) && (defined(BACKLIGHT_PIN) || defined(BACKLIGHT_PINS))
6
7// This logic is a bit complex, we support 3 setups:
8//
9// 1. Hardware PWM when backlight is wired to a PWM pin.
10// Depending on this pin, we use a different output compare unit.
11// 2. Software PWM with hardware timers, but the used timer
12// depends on the Audio setup (Audio wins over Backlight).
13// 3. Full software PWM, driven by the matrix scan, if both timers are used by Audio.
14
15# 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)
16# define HARDWARE_PWM
17# define ICRx ICR1
18# define TCCRxA TCCR1A
19# define TCCRxB TCCR1B
20# define TIMERx_OVF_vect TIMER1_OVF_vect
21# define TIMSKx TIMSK1
22# define TOIEx TOIE1
23
24# if BACKLIGHT_PIN == B5
25# define COMxx1 COM1A1
26# define OCRxx OCR1A
27# elif BACKLIGHT_PIN == B6
28# define COMxx1 COM1B1
29# define OCRxx OCR1B
30# elif BACKLIGHT_PIN == B7
31# define COMxx1 COM1C1
32# define OCRxx OCR1C
33# endif
34# 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)
35# define HARDWARE_PWM
36# define ICRx ICR3
37# define TCCRxA TCCR3A
38# define TCCRxB TCCR3B
39# define TIMERx_OVF_vect TIMER3_OVF_vect
40# define TIMSKx TIMSK3
41# define TOIEx TOIE3
42
43# if BACKLIGHT_PIN == C4
44# if (defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__))
45# error This MCU has no C4 pin!
46# else
47# define COMxx1 COM3C1
48# define OCRxx OCR3C
49# endif
50# elif BACKLIGHT_PIN == C5
51# if (defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__))
52# error This MCU has no C5 pin!
53# else
54# define COMxx1 COM3B1
55# define OCRxx OCR3B
56# endif
57# elif BACKLIGHT_PIN == C6
58# define COMxx1 COM3A1
59# define OCRxx OCR3A
60# endif
61# elif (defined(__AVR_ATmega16U2__) || defined(__AVR_ATmega32U2__)) && (BACKLIGHT_PIN == B7 || BACKLIGHT_PIN == C5 || BACKLIGHT_PIN == C6)
62# define HARDWARE_PWM
63# define ICRx ICR1
64# define TCCRxA TCCR1A
65# define TCCRxB TCCR1B
66# define TIMERx_OVF_vect TIMER1_OVF_vect
67# define TIMSKx TIMSK1
68# define TOIEx TOIE1
69
70# if BACKLIGHT_PIN == B7
71# define COMxx1 COM1C1
72# define OCRxx OCR1C
73# elif BACKLIGHT_PIN == C5
74# define COMxx1 COM1B1
75# define OCRxx OCR1B
76# elif BACKLIGHT_PIN == C6
77# define COMxx1 COM1A1
78# define OCRxx OCR1A
79# endif
80# elif defined(__AVR_ATmega32A__) && (BACKLIGHT_PIN == D4 || BACKLIGHT_PIN == D5)
81# define HARDWARE_PWM
82# define ICRx ICR1
83# define TCCRxA TCCR1A
84# define TCCRxB TCCR1B
85# define TIMERx_OVF_vect TIMER1_OVF_vect
86# define TIMSKx TIMSK
87# define TOIEx TOIE1
88
89# if BACKLIGHT_PIN == D4
90# define COMxx1 COM1B1
91# define OCRxx OCR1B
92# elif BACKLIGHT_PIN == D5
93# define COMxx1 COM1A1
94# define OCRxx OCR1A
95# endif
96# elif defined(__AVR_ATmega328P__) && (BACKLIGHT_PIN == B1 || BACKLIGHT_PIN == B2)
97# define HARDWARE_PWM
98# define ICRx ICR1
99# define TCCRxA TCCR1A
100# define TCCRxB TCCR1B
101# define TIMERx_OVF_vect TIMER1_OVF_vect
102# define TIMSKx TIMSK1
103# define TOIEx TOIE1
104
105# if BACKLIGHT_PIN == B1
106# define COMxx1 COM1A1
107# define OCRxx OCR1A
108# elif BACKLIGHT_PIN == B2
109# define COMxx1 COM1B1
110# define OCRxx OCR1B
111# endif
112# else
113# if !defined(BACKLIGHT_CUSTOM_DRIVER)
114# if !defined(B5_AUDIO) && !defined(B6_AUDIO) && !defined(B7_AUDIO)
115// Timer 1 is not in use by Audio feature, Backlight can use it
116# pragma message "Using hardware timer 1 with software PWM"
117# define HARDWARE_PWM
118# define BACKLIGHT_PWM_TIMER
119# define ICRx ICR1
120# define TCCRxA TCCR1A
121# define TCCRxB TCCR1B
122# define TIMERx_COMPA_vect TIMER1_COMPA_vect
123# define TIMERx_OVF_vect TIMER1_OVF_vect
124# if defined(__AVR_ATmega32A__) // This MCU has only one TIMSK register
125# define TIMSKx TIMSK
126# else
127# define TIMSKx TIMSK1
128# endif
129# define TOIEx TOIE1
130
131# define OCIExA OCIE1A
132# define OCRxx OCR1A
133# elif !defined(C6_AUDIO) && !defined(C5_AUDIO) && !defined(C4_AUDIO)
134# pragma message "Using hardware timer 3 with software PWM"
135// Timer 3 is not in use by Audio feature, Backlight can use it
136# define HARDWARE_PWM
137# define BACKLIGHT_PWM_TIMER
138# define ICRx ICR1
139# define TCCRxA TCCR3A
140# define TCCRxB TCCR3B
141# define TIMERx_COMPA_vect TIMER3_COMPA_vect
142# define TIMERx_OVF_vect TIMER3_OVF_vect
143# define TIMSKx TIMSK3
144# define TOIEx TOIE3
145
146# define OCIExA OCIE3A
147# define OCRxx OCR3A
148# else
149# pragma message "Audio in use - using pure software PWM"
150# define NO_HARDWARE_PWM
151# endif
152# else
153# pragma message "Custom driver defined - using pure software PWM"
154# define NO_HARDWARE_PWM
155# endif
156# endif
157
158# ifndef BACKLIGHT_ON_STATE
159# define BACKLIGHT_ON_STATE 0
160# endif
161
162void backlight_on(uint8_t backlight_pin) {
163# if BACKLIGHT_ON_STATE == 0
164 writePinLow(backlight_pin);
165# else
166 writePinHigh(backlight_pin);
167# endif
168}
169
170void backlight_off(uint8_t backlight_pin) {
171# if BACKLIGHT_ON_STATE == 0
172 writePinHigh(backlight_pin);
173# else
174 writePinLow(backlight_pin);
175# endif
176}
177
178# if defined(NO_HARDWARE_PWM) || defined(BACKLIGHT_PWM_TIMER) // pwm through software
179
180// we support multiple backlight pins
181# ifndef BACKLIGHT_LED_COUNT
182# define BACKLIGHT_LED_COUNT 1
183# endif
184
185# if BACKLIGHT_LED_COUNT == 1
186# define BACKLIGHT_PIN_INIT \
187 { BACKLIGHT_PIN }
188# else
189# define BACKLIGHT_PIN_INIT BACKLIGHT_PINS
190# endif
191
192# define FOR_EACH_LED(x) \
193 for (uint8_t i = 0; i < BACKLIGHT_LED_COUNT; i++) { \
194 uint8_t backlight_pin = backlight_pins[i]; \
195 { x } \
196 }
197
198static const uint8_t backlight_pins[BACKLIGHT_LED_COUNT] = BACKLIGHT_PIN_INIT;
199
200# else // full hardware PWM
201
202// we support only one backlight pin
203static const uint8_t backlight_pin = BACKLIGHT_PIN;
204# define FOR_EACH_LED(x) x
205
206# endif
207
208# ifdef NO_HARDWARE_PWM
209__attribute__((weak)) void backlight_init_ports(void) {
210 // Setup backlight pin as output and output to on state.
211 FOR_EACH_LED(setPinOutput(backlight_pin); backlight_on(backlight_pin);)
212
213# ifdef BACKLIGHT_BREATHING
214 if (is_backlight_breathing()) {
215 breathing_enable();
216 }
217# endif
218}
219
220__attribute__((weak)) void backlight_set(uint8_t level) {}
221
222uint8_t backlight_tick = 0;
223
224# ifndef BACKLIGHT_CUSTOM_DRIVER
225void backlight_task(void) {
226 if ((0xFFFF >> ((BACKLIGHT_LEVELS - get_backlight_level()) * ((BACKLIGHT_LEVELS + 1) / 2))) & (1 << backlight_tick)) {
227 FOR_EACH_LED(backlight_on(backlight_pin);)
228 } else {
229 FOR_EACH_LED(backlight_off(backlight_pin);)
230 }
231 backlight_tick = (backlight_tick + 1) % 16;
232}
233# endif
234
235# ifdef BACKLIGHT_BREATHING
236# ifndef BACKLIGHT_CUSTOM_DRIVER
237# error "Backlight breathing only available with hardware PWM. Please disable."
238# endif
239# endif
240
241# else // hardware pwm through timer
242
243# ifdef BACKLIGHT_PWM_TIMER
244
245// The idea of software PWM assisted by hardware timers is the following
246// we use the hardware timer in fast PWM mode like for hardware PWM, but
247// instead of letting the Output Match Comparator control the led pin
248// (which is not possible since the backlight is not wired to PWM pins on the
249// CPU), we do the LED on/off by oursleves.
250// The timer is setup to count up to 0xFFFF, and we set the Output Compare
251// register to the current 16bits backlight level (after CIE correction).
252// This means the CPU will trigger a compare match interrupt when the counter
253// reaches the backlight level, where we turn off the LEDs,
254// but also an overflow interrupt when the counter rolls back to 0,
255// in which we're going to turn on the LEDs.
256// The LED will then be on for OCRxx/0xFFFF time, adjusted every 244Hz.
257
258// Triggered when the counter reaches the OCRx value
259ISR(TIMERx_COMPA_vect) { FOR_EACH_LED(backlight_off(backlight_pin);) }
260
261// Triggered when the counter reaches the TOP value
262// this one triggers at F_CPU/65536 =~ 244 Hz
263ISR(TIMERx_OVF_vect) {
264# ifdef BACKLIGHT_BREATHING
265 if (is_breathing()) {
266 breathing_task();
267 }
268# endif
269 // for very small values of OCRxx (or backlight level)
270 // we can't guarantee this whole code won't execute
271 // at the same time as the compare match interrupt
272 // which means that we might turn on the leds while
273 // trying to turn them off, leading to flickering
274 // artifacts (especially while breathing, because breathing_task
275 // takes many computation cycles).
276 // so better not turn them on while the counter TOP is very low.
277 if (OCRxx > 256) {
278 FOR_EACH_LED(backlight_on(backlight_pin);)
279 }
280}
281
282# endif
283
284# define TIMER_TOP 0xFFFFU
285
286// See http://jared.geek.nz/2013/feb/linear-led-pwm
287static uint16_t cie_lightness(uint16_t v) {
288 if (v <= 5243) // if below 8% of max
289 return v / 9; // same as dividing by 900%
290 else {
291 uint32_t y = (((uint32_t)v + 10486) << 8) / (10486 + 0xFFFFUL); // add 16% of max and compare
292 // to get a useful result with integer division, we shift left in the expression above
293 // and revert what we've done again after squaring.
294 y = y * y * y >> 8;
295 if (y > 0xFFFFUL) // prevent overflow
296 return 0xFFFFU;
297 else
298 return (uint16_t)y;
299 }
300}
301
302// range for val is [0..TIMER_TOP]. PWM pin is high while the timer count is below val.
303static inline void set_pwm(uint16_t val) { OCRxx = val; }
304
305# ifndef BACKLIGHT_CUSTOM_DRIVER
306__attribute__((weak)) void backlight_set(uint8_t level) {
307 if (level > BACKLIGHT_LEVELS) level = BACKLIGHT_LEVELS;
308
309 if (level == 0) {
310# ifdef BACKLIGHT_PWM_TIMER
311 if (OCRxx) {
312 TIMSKx &= ~(_BV(OCIExA));
313 TIMSKx &= ~(_BV(TOIEx));
314 FOR_EACH_LED(backlight_off(backlight_pin);)
315 }
316# else
317 // Turn off PWM control on backlight pin
318 TCCRxA &= ~(_BV(COMxx1));
319# endif
320 } else {
321# ifdef BACKLIGHT_PWM_TIMER
322 if (!OCRxx) {
323 TIMSKx |= _BV(OCIExA);
324 TIMSKx |= _BV(TOIEx);
325 }
326# else
327 // Turn on PWM control of backlight pin
328 TCCRxA |= _BV(COMxx1);
329# endif
330 }
331 // Set the brightness
332 set_pwm(cie_lightness(TIMER_TOP * (uint32_t)level / BACKLIGHT_LEVELS));
333}
334
335void backlight_task(void) {}
336# endif // BACKLIGHT_CUSTOM_DRIVER
337
338# ifdef BACKLIGHT_BREATHING
339
340# define BREATHING_NO_HALT 0
341# define BREATHING_HALT_OFF 1
342# define BREATHING_HALT_ON 2
343# define BREATHING_STEPS 128
344
345static uint8_t breathing_period = BREATHING_PERIOD;
346static uint8_t breathing_halt = BREATHING_NO_HALT;
347static uint16_t breathing_counter = 0;
348
349# ifdef BACKLIGHT_PWM_TIMER
350static bool breathing = false;
351
352bool is_breathing(void) { return breathing; }
353
354# define breathing_interrupt_enable() \
355 do { \
356 breathing = true; \
357 } while (0)
358# define breathing_interrupt_disable() \
359 do { \
360 breathing = false; \
361 } while (0)
362# else
363
364bool is_breathing(void) { return !!(TIMSKx & _BV(TOIEx)); }
365
366# define breathing_interrupt_enable() \
367 do { \
368 TIMSKx |= _BV(TOIEx); \
369 } while (0)
370# define breathing_interrupt_disable() \
371 do { \
372 TIMSKx &= ~_BV(TOIEx); \
373 } while (0)
374# endif
375
376# define breathing_min() \
377 do { \
378 breathing_counter = 0; \
379 } while (0)
380# define breathing_max() \
381 do { \
382 breathing_counter = breathing_period * 244 / 2; \
383 } while (0)
384
385void breathing_enable(void) {
386 breathing_counter = 0;
387 breathing_halt = BREATHING_NO_HALT;
388 breathing_interrupt_enable();
389}
390
391void breathing_pulse(void) {
392 if (get_backlight_level() == 0)
393 breathing_min();
394 else
395 breathing_max();
396 breathing_halt = BREATHING_HALT_ON;
397 breathing_interrupt_enable();
398}
399
400void breathing_disable(void) {
401 breathing_interrupt_disable();
402 // Restore backlight level
403 backlight_set(get_backlight_level());
404}
405
406void breathing_self_disable(void) {
407 if (get_backlight_level() == 0)
408 breathing_halt = BREATHING_HALT_OFF;
409 else
410 breathing_halt = BREATHING_HALT_ON;
411}
412
413void breathing_toggle(void) {
414 if (is_breathing())
415 breathing_disable();
416 else
417 breathing_enable();
418}
419
420void breathing_period_set(uint8_t value) {
421 if (!value) value = 1;
422 breathing_period = value;
423}
424
425void breathing_period_default(void) { breathing_period_set(BREATHING_PERIOD); }
426
427void breathing_period_inc(void) { breathing_period_set(breathing_period + 1); }
428
429void breathing_period_dec(void) { breathing_period_set(breathing_period - 1); }
430
431/* To generate breathing curve in python:
432 * from math import sin, pi; [int(sin(x/128.0*pi)**4*255) for x in range(128)]
433 */
434static 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};
435
436// Use this before the cie_lightness function.
437static inline uint16_t scale_backlight(uint16_t v) { return v / BACKLIGHT_LEVELS * get_backlight_level(); }
438
439# ifdef BACKLIGHT_PWM_TIMER
440void breathing_task(void)
441# else
442/* Assuming a 16MHz CPU clock and a timer that resets at 64k (ICR1), the following interrupt handler will run
443 * about 244 times per second.
444 */
445ISR(TIMERx_OVF_vect)
446# endif
447{
448 uint16_t interval = (uint16_t)breathing_period * 244 / BREATHING_STEPS;
449 // resetting after one period to prevent ugly reset at overflow.
450 breathing_counter = (breathing_counter + 1) % (breathing_period * 244);
451 uint8_t index = breathing_counter / interval % BREATHING_STEPS;
452
453 if (((breathing_halt == BREATHING_HALT_ON) && (index == BREATHING_STEPS / 2)) || ((breathing_halt == BREATHING_HALT_OFF) && (index == BREATHING_STEPS - 1))) {
454 breathing_interrupt_disable();
455 }
456
457 set_pwm(cie_lightness(scale_backlight((uint16_t)pgm_read_byte(&breathing_table[index]) * 0x0101U)));
458}
459
460# endif // BACKLIGHT_BREATHING
461
462__attribute__((weak)) void backlight_init_ports(void) {
463 // Setup backlight pin as output and output to on state.
464 FOR_EACH_LED(setPinOutput(backlight_pin); backlight_on(backlight_pin);)
465
466 // I could write a wall of text here to explain... but TL;DW
467 // Go read the ATmega32u4 datasheet.
468 // And this: http://blog.saikoled.com/post/43165849837/secret-konami-cheat-code-to-high-resolution-pwm-on
469
470# ifdef BACKLIGHT_PWM_TIMER
471 // TimerX setup, Fast PWM mode count to TOP set in ICRx
472 TCCRxA = _BV(WGM11); // = 0b00000010;
473 // clock select clk/1
474 TCCRxB = _BV(WGM13) | _BV(WGM12) | _BV(CS10); // = 0b00011001;
475# else // hardware PWM
476 // Pin PB7 = OCR1C (Timer 1, Channel C)
477 // Compare Output Mode = Clear on compare match, Channel C = COM1C1=1 COM1C0=0
478 // (i.e. start high, go low when counter matches.)
479 // WGM Mode 14 (Fast PWM) = WGM13=1 WGM12=1 WGM11=1 WGM10=0
480 // Clock Select = clk/1 (no prescaling) = CS12=0 CS11=0 CS10=1
481
482 /*
483 14.8.3:
484 "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 [..]."
485 "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)."
486 */
487 TCCRxA = _BV(COMxx1) | _BV(WGM11); // = 0b00001010;
488 TCCRxB = _BV(WGM13) | _BV(WGM12) | _BV(CS10); // = 0b00011001;
489# endif
490 // Use full 16-bit resolution. Counter counts to ICR1 before reset to 0.
491 ICRx = TIMER_TOP;
492
493 backlight_init();
494# ifdef BACKLIGHT_BREATHING
495 if (is_backlight_breathing()) {
496 breathing_enable();
497 }
498# endif
499}
500
501# endif // hardware backlight
502
503#else // no backlight
504
505__attribute__((weak)) void backlight_init_ports(void) {}
506
507__attribute__((weak)) void backlight_set(uint8_t level) {}
508
509#endif // backlight \ No newline at end of file
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