diff options
Diffstat (limited to 'platforms/chibios/sleep_led.c')
| -rw-r--r-- | platforms/chibios/sleep_led.c | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/platforms/chibios/sleep_led.c b/platforms/chibios/sleep_led.c new file mode 100644 index 0000000000..477056a454 --- /dev/null +++ b/platforms/chibios/sleep_led.c @@ -0,0 +1,192 @@ +#include <ch.h> +#include <hal.h> + +#include "led.h" +#include "sleep_led.h" + +/* All right, we go the "software" way: timer, toggle LED in interrupt. + * Based on hasu's code for AVRs. + * Use LP timer on Kinetises, TIM14 on STM32F0. + */ + +#ifndef SLEEP_LED_GPT_DRIVER +# if defined(STM32F0XX) +# define SLEEP_LED_GPT_DRIVER GPTD14 +# endif +#endif + +#if defined(KL2x) || defined(K20x) || defined(SLEEP_LED_GPT_DRIVER) /* common parts for timers/interrupts */ + +/* Breathing Sleep LED brighness(PWM On period) table + * (64[steps] * 4[duration]) / 64[PWM periods/s] = 4 second breath cycle + * + * http://www.wolframalpha.com/input/?i=%28sin%28+x%2F64*pi%29**8+*+255%2C+x%3D0+to+63 + * (0..63).each {|x| p ((sin(x/64.0*PI)**8)*255).to_i } + */ +static const uint8_t breathing_table[64] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 4, 6, 10, 15, 23, 32, 44, 58, 74, 93, 113, 135, 157, 179, 199, 218, 233, 245, 252, 255, 252, 245, 233, 218, 199, 179, 157, 135, 113, 93, 74, 58, 44, 32, 23, 15, 10, 6, 4, 2, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}; + +void sleep_led_timer_callback(void) { + /* Software PWM + * timer:1111 1111 1111 1111 + * \_____/\/ \_______/____ count(0-255) + * \ \______________ duration of step(4) + * \__________________ index of step table(0-63) + */ + + // this works for cca 65536 irqs/sec + static union { + uint16_t row; + struct { + uint8_t count : 8; + uint8_t duration : 2; + uint8_t index : 6; + } pwm; + } timer = {.row = 0}; + + timer.row++; + + // LED on + if (timer.pwm.count == 0) { + led_set(1 << USB_LED_CAPS_LOCK); + } + // LED off + if (timer.pwm.count == breathing_table[timer.pwm.index]) { + led_set(0); + } +} + +#endif /* common parts for known platforms */ + +#if defined(KL2x) || defined(K20x) /* platform selection: familiar Kinetis chips */ + +/* Use Low Power Timer (LPTMR) */ +# define TIMER_INTERRUPT_VECTOR KINETIS_LPTMR0_IRQ_VECTOR +# define RESET_COUNTER LPTMR0->CSR |= LPTMRx_CSR_TCF + +/* LPTMR clock options */ +# define LPTMR_CLOCK_MCGIRCLK 0 /* 4MHz clock */ +# define LPTMR_CLOCK_LPO 1 /* 1kHz clock */ +# define LPTMR_CLOCK_ERCLK32K 2 /* external 32kHz crystal */ +# define LPTMR_CLOCK_OSCERCLK 3 /* output from OSC */ + +/* Work around inconsistencies in Freescale naming */ +# if !defined(SIM_SCGC5_LPTMR) +# define SIM_SCGC5_LPTMR SIM_SCGC5_LPTIMER +# endif + +/* interrupt handler */ +OSAL_IRQ_HANDLER(TIMER_INTERRUPT_VECTOR) { + OSAL_IRQ_PROLOGUE(); + + sleep_led_timer_callback(); + + /* Reset the counter */ + RESET_COUNTER; + + OSAL_IRQ_EPILOGUE(); +} + +/* Initialise the timer */ +void sleep_led_init(void) { + /* Make sure the clock to the LPTMR is enabled */ + SIM->SCGC5 |= SIM_SCGC5_LPTMR; + /* Reset LPTMR settings */ + LPTMR0->CSR = 0; + /* Set the compare value */ + LPTMR0->CMR = 0; // trigger on counter value (i.e. every time) + +/* Set up clock source and prescaler */ +/* Software PWM + * ______ ______ __ + * | ON |___OFF___| ON |___OFF___| .... + * |<-------------->|<-------------->|<- .... + * PWM period PWM period + * + * R interrupts/period[resolution] + * F periods/second[frequency] + * R * F interrupts/second + */ + +/* === OPTION 1 === */ +# if 0 + // 1kHz LPO + // No prescaler => 1024 irqs/sec + // Note: this is too slow for a smooth breathe + LPTMR0->PSR = LPTMRx_PSR_PCS(LPTMR_CLOCK_LPO)|LPTMRx_PSR_PBYP; +# endif /* OPTION 1 */ + +/* === OPTION 2 === */ +# if 1 + // nMHz IRC (n=4 on KL25Z, KL26Z and K20x; n=2 or 8 on KL27Z) + MCG->C2 |= MCG_C2_IRCS; // fast (4MHz) internal ref clock +# if defined(KL27) // divide the 8MHz IRC by 2, to have the same MCGIRCLK speed as others + MCG->MC |= MCG_MC_LIRC_DIV2_DIV2; +# endif /* KL27 */ + MCG->C1 |= MCG_C1_IRCLKEN; // enable internal ref clock + // to work in stop mode, also MCG_C1_IREFSTEN + // Divide 4MHz by 2^N (N=6) => 62500 irqs/sec => + // => approx F=61, R=256, duration = 4 + LPTMR0->PSR = LPTMRx_PSR_PCS(LPTMR_CLOCK_MCGIRCLK) | LPTMRx_PSR_PRESCALE(6); +# endif /* OPTION 2 */ + +/* === OPTION 3 === */ +# if 0 + // OSC output (external crystal), usually 8MHz or 16MHz + OSC0->CR |= OSC_CR_ERCLKEN; // enable ext ref clock + // to work in stop mode, also OSC_CR_EREFSTEN + // Divide by 2^N + LPTMR0->PSR = LPTMRx_PSR_PCS(LPTMR_CLOCK_OSCERCLK)|LPTMRx_PSR_PRESCALE(7); +# endif /* OPTION 3 */ + /* === END OPTIONS === */ + + /* Interrupt on TCF set (compare flag) */ + nvicEnableVector(LPTMR0_IRQn, 2); // vector, priority + LPTMR0->CSR |= LPTMRx_CSR_TIE; +} + +void sleep_led_enable(void) { + /* Enable the timer */ + LPTMR0->CSR |= LPTMRx_CSR_TEN; +} + +void sleep_led_disable(void) { + /* Disable the timer */ + LPTMR0->CSR &= ~LPTMRx_CSR_TEN; +} + +void sleep_led_toggle(void) { + /* Toggle the timer */ + LPTMR0->CSR ^= LPTMRx_CSR_TEN; +} + +#elif defined(SLEEP_LED_GPT_DRIVER) + +static void gptTimerCallback(GPTDriver *gptp) { + (void)gptp; + sleep_led_timer_callback(); +} + +static const GPTConfig gptcfg = {1000000, gptTimerCallback, 0, 0}; + +/* Initialise the timer */ +void sleep_led_init(void) { gptStart(&SLEEP_LED_GPT_DRIVER, &gptcfg); } + +void sleep_led_enable(void) { gptStartContinuous(&SLEEP_LED_GPT_DRIVER, gptcfg.frequency / 0xFFFF); } + +void sleep_led_disable(void) { gptStopTimer(&SLEEP_LED_GPT_DRIVER); } + +void sleep_led_toggle(void) { (SLEEP_LED_GPT_DRIVER.state == GPT_READY) ? sleep_led_enable() : sleep_led_disable(); } + +#else /* platform selection: not on familiar chips */ + +void sleep_led_init(void) {} + +void sleep_led_enable(void) { led_set(1 << USB_LED_CAPS_LOCK); } + +void sleep_led_disable(void) { led_set(0); } + +void sleep_led_toggle(void) { + // not implemented +} + +#endif /* platform selection */ |