diff options
Diffstat (limited to 'watch-library/hardware/watch/watch_private.c')
-rw-r--r-- | watch-library/hardware/watch/watch_private.c | 423 |
1 files changed, 423 insertions, 0 deletions
diff --git a/watch-library/hardware/watch/watch_private.c b/watch-library/hardware/watch/watch_private.c new file mode 100644 index 00000000..ae2589e7 --- /dev/null +++ b/watch-library/hardware/watch/watch_private.c @@ -0,0 +1,423 @@ +/* + * MIT License + * + * Copyright (c) 2020 Joey Castillo + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all + * copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include "watch_private.h" +#include "watch_utility.h" +#include "tusb.h" + +void _watch_init(void) { + // disable the LED pin (it may have been enabled by the bootloader) + watch_disable_digital_output(RED); + + // RAM should be back-biased in STANDBY + PM->STDBYCFG.bit.BBIASHS = 1; + + // Use switching regulator for lower power consumption. + SUPC->VREG.bit.SEL = 1; + while(!SUPC->STATUS.bit.VREGRDY); + + // set up the brownout detector (low battery warning) + NVIC_DisableIRQ(SYSTEM_IRQn); + NVIC_ClearPendingIRQ(SYSTEM_IRQn); + NVIC_EnableIRQ(SYSTEM_IRQn); + SUPC->BOD33.bit.ENABLE = 0; // BOD33 must be disabled to change its configuration + SUPC->BOD33.bit.VMON = 0; // Monitor VDD in active and standby mode + SUPC->BOD33.bit.ACTCFG = 1; // Enable sampling mode when active + SUPC->BOD33.bit.RUNSTDBY = 1; // Enable sampling mode in standby + SUPC->BOD33.bit.STDBYCFG = 1; // Run in standby + SUPC->BOD33.bit.RUNBKUP = 0; // Don't run in backup mode + SUPC->BOD33.bit.PSEL = 0xB; // Check battery level every 4 seconds + SUPC->BOD33.bit.LEVEL = 31; // Detect brownout at 2.5V (1.445V + level * 34mV) + SUPC->BOD33.bit.ACTION = 0x2; // Generate an interrupt when BOD33 is triggered + SUPC->BOD33.bit.HYST = 0; // Disable hysteresis + while(!SUPC->STATUS.bit.B33SRDY); + + // Enable interrupt on BOD33 detect + SUPC->INTENSET.bit.BOD33DET = 1; + SUPC->BOD33.bit.ENABLE = 1; + + // External wake depends on RTC; calendar is a required module. + _watch_rtc_init(); + + // set up state + btn_alarm_callback = NULL; + a2_callback = NULL; + a4_callback = NULL; +} + +static inline void _watch_wait_for_entropy() { + while (!hri_trng_get_INTFLAG_reg(TRNG, TRNG_INTFLAG_DATARDY)); +} + +// this function is called by arc4random to get entropy for random number generation. +// let's use the SAM L22's true random number generator to seed the PRNG! +int getentropy(void *buf, size_t buflen) { + hri_mclk_set_APBCMASK_TRNG_bit(MCLK); + hri_trng_set_CTRLA_ENABLE_bit(TRNG); + + size_t i = 0; + while(i < buflen / 4) { + _watch_wait_for_entropy(); + ((uint32_t *)buf)[i++] = hri_trng_read_DATA_reg(TRNG); + } + + // but what if they asked for an awkward number of bytes? + if (buflen % 4) { + // all good: let's fill in one, two or three bytes at the end of the buffer. + _watch_wait_for_entropy(); + uint32_t last_little_bit = hri_trng_read_DATA_reg(TRNG); + for(size_t j = 0; j <= (buflen % 4); j++) { + ((uint8_t *)buf)[i * 4 + j] = (last_little_bit >> (j * 8)) & 0xFF; + } + } + + hri_trng_clear_CTRLA_ENABLE_bit(TRNG); + hri_mclk_clear_APBCMASK_TRNG_bit(MCLK); + + return 0; +} + +int _gettimeofday(struct timeval *tv, void *tzvp) { + (void)tzvp; + watch_date_time date_time = watch_rtc_get_date_time(); + + // FIXME: this assumes the system time is UTC! Will break for any other time zone. + tv->tv_sec = watch_utility_date_time_to_unix_time(date_time, 0); + tv->tv_usec = 0; + + return 0; +} + +void _watch_enable_tcc(void) { + // clock TCC0 with the main clock (8 MHz) and enable the peripheral clock. + hri_gclk_write_PCHCTRL_reg(GCLK, TCC0_GCLK_ID, GCLK_PCHCTRL_GEN_GCLK0_Val | GCLK_PCHCTRL_CHEN); + hri_mclk_set_APBCMASK_TCC0_bit(MCLK); + // disable and reset TCC0. + hri_tcc_clear_CTRLA_ENABLE_bit(TCC0); + hri_tcc_wait_for_sync(TCC0, TCC_SYNCBUSY_ENABLE); + hri_tcc_write_CTRLA_reg(TCC0, TCC_CTRLA_SWRST); + hri_tcc_wait_for_sync(TCC0, TCC_SYNCBUSY_SWRST); + // divide the clock down to 1 MHz + if (hri_usbdevice_get_CTRLA_ENABLE_bit(USB)) { + // if USB is enabled, we are running an 8 MHz clock. + hri_tcc_write_CTRLA_reg(TCC0, TCC_CTRLA_PRESCALER_DIV8); + } else { + // otherwise it's 4 Mhz. + hri_tcc_write_CTRLA_reg(TCC0, TCC_CTRLA_PRESCALER_DIV4); + } + // We're going to use normal PWM mode, which means period is controlled by PER, and duty cycle is controlled by + // each compare channel's value: + // * Buzzer tones are set by setting PER to the desired period for a given frequency, and CC[1] to half of that + // period (i.e. a square wave with a 50% duty cycle). + // * LEDs on CC[2] and CC[3] can be set to any value from 0 (off) to PER (fully on). + hri_tcc_write_WAVE_reg(TCC0, TCC_WAVE_WAVEGEN_NPWM); + #ifdef WATCH_INVERT_LED_POLARITY + // This is here for the dev board, which uses a common anode LED (instead of common cathode like the actual watch). + hri_tcc_set_WAVE_reg(TCC0, (1 << (TCC_WAVE_POL0_Pos + WATCH_RED_TCC_CHANNEL)) | + (1 << (TCC_WAVE_POL0_Pos + WATCH_GREEN_TCC_CHANNEL))); + #endif + // The buzzer will set the period depending on the tone it wants to play, but we have to set some period here to + // get the LED working. Almost any period will do, tho it should be below 20000 (i.e. 50 Hz) to avoid flickering. + hri_tcc_write_PER_reg(TCC0, 4096); + // Set the duty cycle of all pins to 0: LED's off, buzzer not buzzing. + hri_tcc_write_CC_reg(TCC0, WATCH_BUZZER_TCC_CHANNEL, 0); + hri_tcc_write_CC_reg(TCC0, WATCH_RED_TCC_CHANNEL, 0); + hri_tcc_write_CC_reg(TCC0, WATCH_GREEN_TCC_CHANNEL, 0); + // Enable the TCC + hri_tcc_set_CTRLA_ENABLE_bit(TCC0); + hri_tcc_wait_for_sync(TCC0, TCC_SYNCBUSY_ENABLE); + + // enable LED PWM pins (the LED driver assumes if the TCC is on, the pins are enabled) + gpio_set_pin_direction(RED, GPIO_DIRECTION_OUT); + gpio_set_pin_function(RED, WATCH_RED_TCC_PINMUX); + gpio_set_pin_direction(GREEN, GPIO_DIRECTION_OUT); + gpio_set_pin_function(GREEN, WATCH_GREEN_TCC_PINMUX); +} + +void _watch_disable_tcc(void) { + // disable all PWM pins + gpio_set_pin_direction(BUZZER, GPIO_DIRECTION_OFF); + gpio_set_pin_function(BUZZER, GPIO_PIN_FUNCTION_OFF); + gpio_set_pin_direction(RED, GPIO_DIRECTION_OFF); + gpio_set_pin_function(RED, GPIO_PIN_FUNCTION_OFF); + gpio_set_pin_direction(GREEN, GPIO_DIRECTION_OFF); + gpio_set_pin_function(GREEN, GPIO_PIN_FUNCTION_OFF); + + // disable the TCC + hri_tcc_clear_CTRLA_ENABLE_bit(TCC0); + hri_mclk_clear_APBCMASK_TCC0_bit(MCLK); +} + +void _watch_enable_usb(void) { + // disable USB, just in case. + hri_usb_clear_CTRLA_ENABLE_bit(USB); + + // bump clock up to 8 MHz + hri_oscctrl_write_OSC16MCTRL_FSEL_bf(OSCCTRL, OSCCTRL_OSC16MCTRL_FSEL_8_Val); + + // reset flags and disable DFLL + OSCCTRL->INTFLAG.reg = OSCCTRL_INTFLAG_DFLLRDY; + OSCCTRL->DFLLCTRL.reg = 0; + while (!(OSCCTRL->STATUS.reg & OSCCTRL_STATUS_DFLLRDY)); + + // set the coarse and fine values to speed up frequency lock. + uint32_t coarse =(*((uint32_t *)NVMCTRL_OTP5)) >> 26; + OSCCTRL->DFLLVAL.reg = OSCCTRL_DFLLVAL_COARSE(coarse) | + OSCCTRL_DFLLVAL_FINE(0x200); + // set coarse and fine steps, and multiplier (48 MHz = 32768 Hz * 1465) + OSCCTRL->DFLLMUL.reg = OSCCTRL_DFLLMUL_CSTEP( 1 ) | + OSCCTRL_DFLLMUL_FSTEP( 1 ) | + OSCCTRL_DFLLMUL_MUL( 1465 ); + // set closed loop mode, chill cycle disable and USB clock recovery mode, and enable the DFLL. + OSCCTRL->DFLLCTRL.reg = OSCCTRL_DFLLCTRL_MODE | OSCCTRL_DFLLCTRL_CCDIS | OSCCTRL_DFLLCTRL_ONDEMAND | OSCCTRL_DFLLCTRL_RUNSTDBY | OSCCTRL_DFLLCTRL_USBCRM | OSCCTRL_DFLLCTRL_ENABLE; + while (!(OSCCTRL->STATUS.reg & OSCCTRL_STATUS_DFLLRDY)); + + // assign DFLL to GCLK1 + GCLK->GENCTRL[1].reg = GCLK_GENCTRL_SRC(GCLK_GENCTRL_SRC_DFLL48M) | GCLK_GENCTRL_DIV(1) | GCLK_GENCTRL_GENEN;// | GCLK_GENCTRL_OE; + while (GCLK->SYNCBUSY.bit.GENCTRL1); + + // assign GCLK1 to USB + hri_gclk_write_PCHCTRL_reg(GCLK, USB_GCLK_ID, GCLK_PCHCTRL_GEN_GCLK1_Val | GCLK_PCHCTRL_CHEN); + hri_mclk_set_AHBMASK_USB_bit(MCLK); + hri_mclk_set_APBBMASK_USB_bit(MCLK); + + // USB Pin Init + gpio_set_pin_direction(PIN_PA24, GPIO_DIRECTION_OUT); + gpio_set_pin_level(PIN_PA24, false); + gpio_set_pin_pull_mode(PIN_PA24, GPIO_PULL_OFF); + gpio_set_pin_direction(PIN_PA25, GPIO_DIRECTION_OUT); + gpio_set_pin_level(PIN_PA25, false); + gpio_set_pin_pull_mode(PIN_PA25, GPIO_PULL_OFF); + + gpio_set_pin_function(PIN_PA24, PINMUX_PA24G_USB_DM); + gpio_set_pin_function(PIN_PA25, PINMUX_PA25G_USB_DP); + + // before we init TinyUSB, we are going to need a periodic callback to handle TinyUSB tasks. + // TC2 and TC3 are reserved for devices on the 9-pin connector, so let's use TC0. + // clock TC0 with the 8 MHz clock on GCLK0. + hri_gclk_write_PCHCTRL_reg(GCLK, TC0_GCLK_ID, GCLK_PCHCTRL_GEN_GCLK0_Val | GCLK_PCHCTRL_CHEN); + // and enable the peripheral clock. + hri_mclk_set_APBCMASK_TC0_bit(MCLK); + // disable and reset TC0. + hri_tc_clear_CTRLA_ENABLE_bit(TC0); + hri_tc_wait_for_sync(TC0, TC_SYNCBUSY_ENABLE); + hri_tc_write_CTRLA_reg(TC0, TC_CTRLA_SWRST); + hri_tc_wait_for_sync(TC0, TC_SYNCBUSY_SWRST); + // configure the TC to overflow 1,000 times per second + hri_tc_write_CTRLA_reg(TC0, TC_CTRLA_PRESCALER_DIV64 | // divide the 8 MHz clock by 64 to count at 125 KHz + TC_CTRLA_MODE_COUNT8 | // count in 8-bit mode + TC_CTRLA_RUNSTDBY); // run in standby, just in case we figure that out + hri_tccount8_write_PER_reg(TC0, 125); // 125000 Hz / 125 = 1,000 Hz + // set an interrupt on overflow; this will call TC0_Handler below. + hri_tc_set_INTEN_OVF_bit(TC0); + NVIC_ClearPendingIRQ(TC0_IRQn); + NVIC_EnableIRQ (TC0_IRQn); + + // now we can init TinyUSB + tusb_init(); + // and start the timer that handles USB device tasks. + hri_tc_set_CTRLA_ENABLE_bit(TC0); +} + +// this function ends up getting called by printf to log stuff to the USB console. +int _write(int file, char *ptr, int len) { + (void)file; + if (hri_usbdevice_get_CTRLA_ENABLE_bit(USB)) { + tud_cdc_n_write(0, (void const*)ptr, len); + tud_cdc_n_write_flush(0); + return len; + } + + return 0; +} + +// this method could be overridden to read stuff from the USB console? but no need rn. +int _read(void) { + return 0; +} + +// Alternate function that outputs to the debug UART. useful for debugging USB issues. +// int _write(int file, char *ptr, int len) { +// (void)file; +// int pos = 0; +// while(pos < len) watch_debug_putc(ptr[pos++]); + +// return 0; +// } + +void USB_Handler(void) { + tud_int_handler(0); +} + +void TC0_Handler(void) { + tud_task(); + TC0->COUNT8.INTFLAG.reg |= TC_INTFLAG_OVF; +} + + +// USB Descriptors and tinyUSB callbacks follow. + +/* + * The MIT License (MIT) + * + * Copyright (c) 2019 Ha Thach (tinyusb.org) + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + * + */ + +//--------------------------------------------------------------------+ +// Device Descriptors +//--------------------------------------------------------------------+ +tusb_desc_device_t const desc_device = +{ + .bLength = sizeof(tusb_desc_device_t), + .bDescriptorType = TUSB_DESC_DEVICE, + .bcdUSB = 0x0200, + + // Use Interface Association Descriptor (IAD) for CDC + // As required by USB Specs IAD's subclass must be common class (2) and protocol must be IAD (1) + .bDeviceClass = TUSB_CLASS_MISC, + .bDeviceSubClass = MISC_SUBCLASS_COMMON, + .bDeviceProtocol = MISC_PROTOCOL_IAD, + + .bMaxPacketSize0 = CFG_TUD_ENDPOINT0_SIZE, + + .idVendor = 0x1209, + .idProduct = 0x2151, + .bcdDevice = 0x0100, + + .iManufacturer = 0x01, + .iProduct = 0x02, + .iSerialNumber = 0x03, + + .bNumConfigurations = 0x01 +}; + +// Invoked when received GET DEVICE DESCRIPTOR +// Application return pointer to descriptor +uint8_t const * tud_descriptor_device_cb(void) { + return (uint8_t const *) &desc_device; +} + +//--------------------------------------------------------------------+ +// Configuration Descriptor +//--------------------------------------------------------------------+ + +enum { + ITF_NUM_CDC = 0, + ITF_NUM_CDC_DATA, + ITF_NUM_TOTAL +}; + +#define CONFIG_TOTAL_LEN (TUD_CONFIG_DESC_LEN + TUD_CDC_DESC_LEN) + +#define EPNUM_CDC_NOTIF 0x81 +#define EPNUM_CDC_OUT 0x02 +#define EPNUM_CDC_IN 0x82 + + +uint8_t const desc_fs_configuration[] = { + // Config number, interface count, string index, total length, attribute, power in mA + TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, TUSB_DESC_CONFIG_ATT_REMOTE_WAKEUP, 100), + + // Interface number, string index, EP notification address and size, EP data address (out, in) and size. + TUD_CDC_DESCRIPTOR(ITF_NUM_CDC, 4, EPNUM_CDC_NOTIF, 8, EPNUM_CDC_OUT, EPNUM_CDC_IN, 64), +}; + +// Invoked when received GET CONFIGURATION DESCRIPTOR +// Application return pointer to descriptor +// Descriptor contents must exist long enough for transfer to complete +uint8_t const * tud_descriptor_configuration_cb(uint8_t index) { + (void) index; // for multiple configurations + return desc_fs_configuration; +} + +//--------------------------------------------------------------------+ +// String Descriptors +//--------------------------------------------------------------------+ + +// array of pointer to string descriptors +char const* string_desc_arr [] = +{ + (const char[]) { 0x09, 0x04 }, // 0: is supported language is English (0x0409) + "TinyUSB", // 1: Manufacturer + "TinyUSB Device", // 2: Product + "123456", // 3: Serials, should use chip ID + "TinyUSB CDC", // 4: CDC Interface +}; + +static uint16_t _desc_str[32]; + +// Invoked when received GET STRING DESCRIPTOR request +// Application return pointer to descriptor, whose contents must exist long enough for transfer to complete +uint16_t const* tud_descriptor_string_cb(uint8_t index, uint16_t langid) +{ + (void) langid; + + uint8_t chr_count; + + if ( index == 0) { + memcpy(&_desc_str[1], string_desc_arr[0], 2); + chr_count = 1; + } else { + // Note: the 0xEE index string is a Microsoft OS 1.0 Descriptors. + // https://docs.microsoft.com/en-us/windows-hardware/drivers/usbcon/microsoft-defined-usb-descriptors + + if ( !(index < sizeof(string_desc_arr)/sizeof(string_desc_arr[0])) ) return NULL; + + const char* str = string_desc_arr[index]; + + // Cap at max char + chr_count = strlen(str); + if ( chr_count > 31 ) chr_count = 31; + + // Convert ASCII string into UTF-16 + for(uint8_t i=0; i<chr_count; i++) + { + _desc_str[1+i] = str[i]; + } + } + + // first byte is length (including header), second byte is string type + _desc_str[0] = (TUSB_DESC_STRING << 8 ) | (2*chr_count + 2); + + return _desc_str; +} |