2 Copyright 2012 Jun Wako <wakojun@gmail.com>
4 This program is free software: you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation, either version 2 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program. If not, see <http://www.gnu.org/licenses/>.
19 #include "backlight.h"
21 #include "led_custom.h"
24 static void breathing_callback(PWMDriver *pwmp);
26 static PWMConfig pwmCFG = {
27 0xFFFF, /* PWM clock frequency */
28 256, /* PWM period (in ticks) 1S (1/10kHz=0.1mS 0.1ms*10000 ticks=1S) */
29 NULL, /* No Callback */
31 {PWM_OUTPUT_ACTIVE_HIGH, NULL}, /* Enable Channel 0 */
32 {PWM_OUTPUT_DISABLED, NULL},
33 {PWM_OUTPUT_DISABLED, NULL},
34 {PWM_OUTPUT_DISABLED, NULL}
36 0, /* HW dependent part.*/
40 static PWMConfig pwmCFG_breathing = {
41 0xFFFF, /* 10kHz PWM clock frequency */
42 256, /* PWM period (in ticks) 1S (1/10kHz=0.1mS 0.1ms*10000 ticks=1S) */
43 breathing_callback, /* Breathing Callback */
45 {PWM_OUTPUT_ACTIVE_HIGH, NULL}, /* Enable Channel 0 */
46 {PWM_OUTPUT_DISABLED, NULL},
47 {PWM_OUTPUT_DISABLED, NULL},
48 {PWM_OUTPUT_DISABLED, NULL}
50 0, /* HW dependent part.*/
54 // See http://jared.geek.nz/2013/feb/linear-led-pwm
55 static 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%
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.
63 if (y > 0xFFFFUL) // prevent overflow
71 void backlight_init_ports(void) {
72 printf("backlight_init_ports()\n");
73 #ifdef BACKLIGHT_ENABLE
75 palSetPadMode(GPIOA, 8, PAL_MODE_STM32_ALTERNATE_PUSHPULL);
76 pwmStart(&PWMD1, &pwmCFG);
77 pwmEnableChannel(&PWMD1, 0, PWM_FRACTION_TO_WIDTH(&PWMD1, 0xFFFF,cie_lightness(0xFFFF)));
81 void backlight_set(uint8_t level) {
82 printf("backlight_set(%d)\n", level);
83 #ifdef BACKLIGHT_ENABLE
84 uint32_t duty = (uint32_t)(cie_lightness(0xFFFF * (uint32_t) level / BACKLIGHT_LEVELS));
85 printf("duty: (%d)\n", duty);
88 pwmDisableChannel(&PWMD1, 0);
92 pwmEnableChannel(&PWMD1, 0, PWM_FRACTION_TO_WIDTH(&PWMD1,0xFFFF,duty));
99 uint8_t backlight_tick = 0;
101 void backlight_task(void) {
104 #define BREATHING_NO_HALT 0
105 #define BREATHING_HALT_OFF 1
106 #define BREATHING_HALT_ON 2
107 #define BREATHING_STEPS 128
109 static uint8_t breathing_period = BREATHING_PERIOD;
110 static uint8_t breathing_halt = BREATHING_NO_HALT;
111 static uint16_t breathing_counter = 0;
113 bool is_breathing(void) {
114 return PWMD1.config == &pwmCFG_breathing;
117 #define breathing_min() do {breathing_counter = 0;} while (0)
118 #define breathing_max() do {breathing_counter = breathing_period * 256 / 2;} while (0)
121 void breathing_interrupt_enable(void){
123 printf("starting with callback\n");
124 pwmStart(&PWMD1, &pwmCFG_breathing);
126 pwmEnablePeriodicNotification(&PWMD1);
130 PWM_FRACTION_TO_WIDTH(
136 chSysUnlockFromISR();
139 void breathing_interrupt_disable(void){
141 printf("starting without callback\n");
142 pwmStart(&PWMD1, &pwmCFG);
145 void breathing_enable(void)
147 printf("breathing_enable()\n");
148 breathing_counter = 0;
149 breathing_halt = BREATHING_NO_HALT;
150 breathing_interrupt_enable();
153 void breathing_pulse(void)
155 if (get_backlight_level() == 0)
159 breathing_halt = BREATHING_HALT_ON;
160 breathing_interrupt_enable();
163 void breathing_disable(void)
165 printf("breathing_disable()\n");
166 breathing_interrupt_disable();
167 // Restore backlight level
168 backlight_set(get_backlight_level());
171 void breathing_self_disable(void)
173 if (get_backlight_level() == 0)
174 breathing_halt = BREATHING_HALT_OFF;
176 breathing_halt = BREATHING_HALT_ON;
179 void breathing_toggle(void) {
181 printf("disable breathing\n");
184 printf("enable breathing\n");
189 void breathing_period_set(uint8_t value)
193 breathing_period = value;
196 void breathing_period_default(void) {
197 breathing_period_set(BREATHING_PERIOD);
200 void breathing_period_inc(void)
202 breathing_period_set(breathing_period+1);
205 void breathing_period_dec(void)
207 breathing_period_set(breathing_period-1);
210 /* To generate breathing curve in python:
211 * from math import sin, pi; [int(sin(x/128.0*pi)**4*255) for x in range(128)]
213 static 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};
215 // Use this before the cie_lightness function.
216 static inline uint16_t scale_backlight(uint16_t v) {
217 return v / BACKLIGHT_LEVELS * get_backlight_level();
220 static void breathing_callback(PWMDriver *pwmp)
223 uint16_t interval = (uint16_t) breathing_period * 256 / BREATHING_STEPS;
224 // resetting after one period to prevent ugly reset at overflow.
225 breathing_counter = (breathing_counter + 1) % (breathing_period * 256);
226 uint8_t index = breathing_counter / interval % BREATHING_STEPS;
228 if (((breathing_halt == BREATHING_HALT_ON) && (index == BREATHING_STEPS / 2)) ||
229 ((breathing_halt == BREATHING_HALT_OFF) && (index == BREATHING_STEPS - 1)))
231 breathing_interrupt_disable();
234 uint32_t duty = cie_lightness(scale_backlight(breathing_table[index] * 256));
240 PWM_FRACTION_TO_WIDTH(
246 chSysUnlockFromISR();
250 void led_set(uint8_t usb_led)
252 if (usb_led & (1<<USB_LED_CAPS_LOCK)) {
253 palSetPad(GPIOC, 13);
255 palClearPad(GPIOC, 13);