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Fix AVR SPI parameter configuration, remove timeouts due to sync prot…
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…ocol. (qmk#8775)
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@tzarc @fdidron
tzarc authored and fdidron committed Jun 12, 2020
1 parent da7b769 commit 9fe1c38
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Showing 3 changed files with 78 additions and 65 deletions.
123 changes: 68 additions & 55 deletions drivers/avr/spi_master.c
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Original file line number Diff line number Diff line change
Expand Up @@ -34,6 +34,10 @@
# define SPI_MISO_PIN B4
#endif

#ifndef SPI_TIMEOUT
# define SPI_TIMEOUT 100
#endif

static pin_t currentSlavePin = NO_PIN;
static uint8_t currentSlaveConfig = 0;
static bool currentSlave2X = false;
Expand All @@ -47,100 +51,109 @@ void spi_init(void) {
SPCR = (_BV(SPE) | _BV(MSTR));
}

void spi_start(pin_t slavePin, bool lsbFirst, uint8_t mode, uint8_t divisor) {
if (currentSlavePin == NO_PIN && slavePin != NO_PIN) {
if (lsbFirst) {
currentSlaveConfig |= _BV(DORD);
}
bool spi_start(pin_t slavePin, bool lsbFirst, uint8_t mode, uint16_t divisor) {
if (currentSlavePin != NO_PIN || slavePin == NO_PIN) {
return false;
}

switch (mode) {
case 1:
currentSlaveConfig |= _BV(CPHA);
break;
case 2:
currentSlaveConfig |= _BV(CPOL);
break;
case 3:
currentSlaveConfig |= (_BV(CPOL) | _BV(CPHA));
break;
}
currentSlaveConfig = 0;

uint8_t roundedDivisor = 1;
while (roundedDivisor < divisor) {
roundedDivisor <<= 1;
}
if (lsbFirst) {
currentSlaveConfig |= _BV(DORD);
}

switch (roundedDivisor) {
case 16:
currentSlaveConfig |= _BV(SPR0);
break;
case 64:
currentSlaveConfig |= _BV(SPR1);
break;
case 128:
currentSlaveConfig |= (_BV(SPR1) | _BV(SPR0));
break;
case 2:
currentSlave2X = true;
break;
case 8:
currentSlave2X = true;
currentSlaveConfig |= _BV(SPR0);
break;
case 32:
currentSlave2X = true;
currentSlaveConfig |= _BV(SPR1);
break;
}
switch (mode) {
case 1:
currentSlaveConfig |= _BV(CPHA);
break;
case 2:
currentSlaveConfig |= _BV(CPOL);
break;
case 3:
currentSlaveConfig |= (_BV(CPOL) | _BV(CPHA));
break;
}

SPSR |= currentSlaveConfig;
currentSlavePin = slavePin;
setPinOutput(currentSlavePin);
writePinLow(currentSlavePin);
uint16_t roundedDivisor = 1;
while (roundedDivisor < divisor) {
roundedDivisor <<= 1;
}

switch (roundedDivisor) {
case 16:
currentSlaveConfig |= _BV(SPR0);
break;
case 64:
currentSlaveConfig |= _BV(SPR1);
break;
case 128:
currentSlaveConfig |= (_BV(SPR1) | _BV(SPR0));
break;
case 2:
currentSlave2X = true;
break;
case 8:
currentSlave2X = true;
currentSlaveConfig |= _BV(SPR0);
break;
case 32:
currentSlave2X = true;
currentSlaveConfig |= _BV(SPR1);
break;
}

SPCR |= currentSlaveConfig;
if (currentSlave2X) {
SPSR |= _BV(SPI2X);
}
currentSlavePin = slavePin;
setPinOutput(currentSlavePin);
writePinLow(currentSlavePin);

return true;
}

spi_status_t spi_write(uint8_t data, uint16_t timeout) {
spi_status_t spi_write(uint8_t data) {
SPDR = data;

uint16_t timeout_timer = timer_read();
while (!(SPSR & _BV(SPIF))) {
if ((timeout != SPI_TIMEOUT_INFINITE) && ((timer_read() - timeout_timer) >= timeout)) {
if ((timer_read() - timeout_timer) >= SPI_TIMEOUT) {
return SPI_STATUS_TIMEOUT;
}
}

return SPDR;
}

spi_status_t spi_read(uint16_t timeout) {
spi_status_t spi_read() {
SPDR = 0x00; // Dummy

uint16_t timeout_timer = timer_read();
while (!(SPSR & _BV(SPIF))) {
if ((timeout != SPI_TIMEOUT_INFINITE) && ((timer_read() - timeout_timer) >= timeout)) {
if ((timer_read() - timeout_timer) >= SPI_TIMEOUT) {
return SPI_STATUS_TIMEOUT;
}
}

return SPDR;
}

spi_status_t spi_transmit(const uint8_t *data, uint16_t length, uint16_t timeout) {
spi_status_t spi_transmit(const uint8_t *data, uint16_t length) {
spi_status_t status = SPI_STATUS_ERROR;

for (uint16_t i = 0; i < length; i++) {
status = spi_write(data[i], timeout);
status = spi_write(data[i]);
}

return status;
}

spi_status_t spi_receive(uint8_t *data, uint16_t length, uint16_t timeout) {
spi_status_t spi_receive(uint8_t *data, uint16_t length) {
spi_status_t status = SPI_STATUS_ERROR;

for (uint16_t i = 0; i < length; i++) {
status = spi_read(timeout);
status = spi_read();

if (status > 0) {
data[i] = status;
Expand All @@ -155,9 +168,9 @@ void spi_stop(void) {
setPinOutput(currentSlavePin);
writePinHigh(currentSlavePin);
currentSlavePin = NO_PIN;
SPSR &= ~(_BV(SPI2X));
SPCR &= ~(currentSlaveConfig);
currentSlaveConfig = 0;
SPSR = 0;
currentSlave2X = false;
}
}
10 changes: 5 additions & 5 deletions drivers/avr/spi_master.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -41,15 +41,15 @@ extern "C" {
#endif
void spi_init(void);

void spi_start(pin_t slavePin, bool lsbFirst, uint8_t mode, uint8_t divisor);
bool spi_start(pin_t slavePin, bool lsbFirst, uint8_t mode, uint16_t divisor);

spi_status_t spi_write(uint8_t data, uint16_t timeout);
spi_status_t spi_write(uint8_t data);

spi_status_t spi_read(uint16_t timeout);
spi_status_t spi_read(void);

spi_status_t spi_transmit(const uint8_t *data, uint16_t length, uint16_t timeout);
spi_status_t spi_transmit(const uint8_t *data, uint16_t length);

spi_status_t spi_receive(uint8_t *data, uint16_t length, uint16_t timeout);
spi_status_t spi_receive(uint8_t *data, uint16_t length);

void spi_stop(void);
#ifdef __cplusplus
Expand Down
10 changes: 5 additions & 5 deletions tmk_core/protocol/lufa/adafruit_ble.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -152,7 +152,7 @@ static bool sdep_send_pkt(const struct sdep_msg *msg, uint16_t timeout) {
bool ready = false;

do {
ready = spi_write(msg->type, 100) != SdepSlaveNotReady;
ready = spi_write(msg->type) != SdepSlaveNotReady;
if (ready) {
break;
}
Expand All @@ -165,7 +165,7 @@ static bool sdep_send_pkt(const struct sdep_msg *msg, uint16_t timeout) {

if (ready) {
// Slave is ready; send the rest of the packet
spi_transmit(&msg->cmd_low, sizeof(*msg) - (1 + sizeof(msg->payload)) + msg->len, 100);
spi_transmit(&msg->cmd_low, sizeof(*msg) - (1 + sizeof(msg->payload)) + msg->len);
success = true;
}

Expand Down Expand Up @@ -205,7 +205,7 @@ static bool sdep_recv_pkt(struct sdep_msg *msg, uint16_t timeout) {

do {
// Read the command type, waiting for the data to be ready
msg->type = spi_read(100);
msg->type = spi_read();
if (msg->type == SdepSlaveNotReady || msg->type == SdepSlaveOverflow) {
// Release it and let it initialize
spi_stop();
Expand All @@ -215,11 +215,11 @@ static bool sdep_recv_pkt(struct sdep_msg *msg, uint16_t timeout) {
}

// Read the rest of the header
spi_receive(&msg->cmd_low, sizeof(*msg) - (1 + sizeof(msg->payload)), 100);
spi_receive(&msg->cmd_low, sizeof(*msg) - (1 + sizeof(msg->payload)));

// and get the payload if there is any
if (msg->len <= SdepMaxPayload) {
spi_receive(msg->payload, msg->len, 100);
spi_receive(msg->payload, msg->len);
}
success = true;
break;
Expand Down

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