diff options
| -rw-r--r-- | board/keyborg/hardware.c | 12 | ||||
| -rw-r--r-- | board/keyborg/master_slave.c | 25 |
2 files changed, 29 insertions, 8 deletions
diff --git a/board/keyborg/hardware.c b/board/keyborg/hardware.c index 6651cf5b46..c8c106f92b 100644 --- a/board/keyborg/hardware.c +++ b/board/keyborg/hardware.c @@ -66,21 +66,23 @@ static void pins_init(void) STM32_GPIO_AFIO_MAPR = (STM32_GPIO_AFIO_MAPR & ~(0x7 << 24)) | (2 << 24); - /* Pin usage: + /* + * Initial pin usage: * PA0: SPI_NSS - INPUT/INT_FALLING - * PA1: N_CHG - OUTPUT/LOW + * PA1: N_CHG - INPUT * PA3: SPI_CLK - INPUT * PA4: SPI_MISO - INPUT * PA6: CS1 - OUTPUT/HIGH * PA7: SPI_MOSI - INPUT + * PA9: USB_PU - OUTPUT/LOW * PA15: UART TX - OUTPUT/HIGH * PI1: SYNC1 - OUTPUT/LOW * PI2: SYNC2 - OUTPUT/LOW */ - STM32_GPIO_CRL(GPIO_A) = FLOAT(0) | OUT(1) | FLOAT(3) | FLOAT(4) | + STM32_GPIO_CRL(GPIO_A) = FLOAT(0) | FLOAT(1) | FLOAT(3) | FLOAT(4) | OUT(6) | FLOAT(7); - STM32_GPIO_CRH(GPIO_A) = OUT(15); - STM32_GPIO_BSRR(GPIO_A) = LOW(1) | HIGH(6) | HIGH(15); + STM32_GPIO_CRH(GPIO_A) = OUT(9) | OUT(15); + STM32_GPIO_BSRR(GPIO_A) = LOW(1) | HIGH(6) | LOW(9) | HIGH(15); STM32_EXTI_FTSR |= INT(0); STM32_GPIO_CRL(GPIO_I) = OUT(1) | OUT(2); diff --git a/board/keyborg/master_slave.c b/board/keyborg/master_slave.c index 39f41ddddb..eab62b1b73 100644 --- a/board/keyborg/master_slave.c +++ b/board/keyborg/master_slave.c @@ -54,7 +54,7 @@ static int master_handshake(void) uint32_t val; int err; - /* SYNC2 -> GPIO_INPUT */ + /* SYNC2 is the sync signal from the slave. Set it to input. */ val = STM32_GPIO_CRL(GPIO_I); val &= ~0x00000f00; val |= 0x00000400; @@ -72,7 +72,17 @@ static int slave_handshake(void) uint32_t val; int err; - /* SYNC1 -> GPIO_INPUT */ + /* + * N_CHG is used to drive SPI_NSS on the master. Set it to + * output low. + */ + val = STM32_GPIO_CRL(GPIO_A); + val &= ~0x000000f0; + val |= 0x00000010; + STM32_GPIO_CRL(GPIO_A) = val; + STM32_GPIO_BSRR(GPIO_A) = 1 << (1 + 16); + + /* SYNC1 is the sync signal from the master. Set it to input. */ val = STM32_GPIO_CRL(GPIO_I); val &= ~0x000000f0; val |= 0x00000040; @@ -87,7 +97,16 @@ static int slave_handshake(void) static void master_slave_check(void) { - if (STM32_GPIO_IDR(GPIO_A) & (1 << 0) /* NSS */) { + /* + * Master slave identity check: + * - Master has USB_PU connected to N_CHG through 1.5K + * resistor. USB_PU is initially low, so N_CHG is low. + * - Slave has N_CHG connected to master NSS with a 20K + * pull-up. Master NSS is initially Hi-Z, so N_CHG is + * high. + */ + + if (STM32_GPIO_IDR(GPIO_A) & (1 << 1) /* N_CHG */) { debug_printf("I'm slave\n"); is_master = 0; } else { |