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authorDasky <[email protected]>2024-09-09 23:44:35 +0100
committerGitHub <[email protected]>2024-09-10 08:44:35 +1000
commit2c7bf34d09247c2f306f0068e34a2a3a4f3f58e1 (patch)
tree63052adc2c43f2e676bed9dc4957f961f3cb4eff /platforms/avr
parent3aaa086ac8a50ed7fc501c2dc93c1d195b63dcc3 (diff)
downloadqmk_firmware-2c7bf34d09247c2f306f0068e34a2a3a4f3f58e1.tar.gz
qmk_firmware-2c7bf34d09247c2f306f0068e34a2a3a4f3f58e1.zip
Allow for inverted SPI CS logic (#23699)
Diffstat (limited to 'platforms/avr')
-rw-r--r--platforms/avr/drivers/spi_master.c84
-rw-r--r--platforms/avr/drivers/spi_master.h9
2 files changed, 61 insertions, 32 deletions
diff --git a/platforms/avr/drivers/spi_master.c b/platforms/avr/drivers/spi_master.c
index 74b847c71a..ba7d782ab0 100644
--- a/platforms/avr/drivers/spi_master.c
+++ b/platforms/avr/drivers/spi_master.c
@@ -36,9 +36,18 @@
# define SPI_TIMEOUT 100
#endif
-static pin_t currentSlavePin = NO_PIN;
-static uint8_t currentSlaveConfig = 0;
-static bool currentSlave2X = false;
+static pin_t current_slave_pin = NO_PIN;
+static bool current_cs_active_low = true;
+static uint8_t current_slave_config = 0;
+static bool current_slave_2x = false;
+
+static inline void spi_select(void) {
+ gpio_write_pin(current_slave_pin, current_cs_active_low ? 0 : 1);
+}
+
+static inline void spi_unselect(void) {
+ gpio_write_pin(current_slave_pin, current_cs_active_low ? 1 : 0);
+}
void spi_init(void) {
gpio_write_pin_high(SPI_SS_PIN);
@@ -50,63 +59,74 @@ void spi_init(void) {
}
bool spi_start(pin_t slavePin, bool lsbFirst, uint8_t mode, uint16_t divisor) {
- if (currentSlavePin != NO_PIN || slavePin == NO_PIN) {
+ spi_start_config_t start_config = {0};
+ start_config.slave_pin = slavePin;
+ start_config.lsb_first = lsbFirst;
+ start_config.mode = mode;
+ start_config.divisor = divisor;
+ start_config.cs_active_low = true;
+ return spi_start_extended(&start_config);
+}
+
+bool spi_start_extended(spi_start_config_t *start_config) {
+ if (current_slave_pin != NO_PIN || start_config->slave_pin == NO_PIN) {
return false;
}
- currentSlaveConfig = 0;
+ current_slave_config = 0;
- if (lsbFirst) {
- currentSlaveConfig |= _BV(DORD);
+ if (start_config->lsb_first) {
+ current_slave_config |= _BV(DORD);
}
- switch (mode) {
+ switch (start_config->mode) {
case 1:
- currentSlaveConfig |= _BV(CPHA);
+ current_slave_config |= _BV(CPHA);
break;
case 2:
- currentSlaveConfig |= _BV(CPOL);
+ current_slave_config |= _BV(CPOL);
break;
case 3:
- currentSlaveConfig |= (_BV(CPOL) | _BV(CPHA));
+ current_slave_config |= (_BV(CPOL) | _BV(CPHA));
break;
}
uint16_t roundedDivisor = 1;
- while (roundedDivisor < divisor) {
+ while (roundedDivisor < start_config->divisor) {
roundedDivisor <<= 1;
}
switch (roundedDivisor) {
case 16:
- currentSlaveConfig |= _BV(SPR0);
+ current_slave_config |= _BV(SPR0);
break;
case 64:
- currentSlaveConfig |= _BV(SPR1);
+ current_slave_config |= _BV(SPR1);
break;
case 128:
- currentSlaveConfig |= (_BV(SPR1) | _BV(SPR0));
+ current_slave_config |= (_BV(SPR1) | _BV(SPR0));
break;
case 2:
- currentSlave2X = true;
+ current_slave_2x = true;
break;
case 8:
- currentSlave2X = true;
- currentSlaveConfig |= _BV(SPR0);
+ current_slave_2x = true;
+ current_slave_config |= _BV(SPR0);
break;
case 32:
- currentSlave2X = true;
- currentSlaveConfig |= _BV(SPR1);
+ current_slave_2x = true;
+ current_slave_config |= _BV(SPR1);
break;
}
- SPCR |= currentSlaveConfig;
- if (currentSlave2X) {
+ SPCR |= current_slave_config;
+ if (current_slave_2x) {
SPSR |= _BV(SPI2X);
}
- currentSlavePin = slavePin;
- gpio_set_pin_output(currentSlavePin);
- gpio_write_pin_low(currentSlavePin);
+ current_slave_pin = start_config->slave_pin;
+ current_cs_active_low = start_config->cs_active_low;
+ gpio_set_pin_output(current_slave_pin);
+ spi_select();
return true;
}
@@ -168,13 +188,13 @@ spi_status_t spi_receive(uint8_t *data, uint16_t length) {
}
void spi_stop(void) {
- if (currentSlavePin != NO_PIN) {
- gpio_set_pin_output(currentSlavePin);
- gpio_write_pin_high(currentSlavePin);
- currentSlavePin = NO_PIN;
+ if (current_slave_pin != NO_PIN) {
+ gpio_set_pin_output(current_slave_pin);
+ spi_unselect();
+ current_slave_pin = NO_PIN;
SPSR &= ~(_BV(SPI2X));
- SPCR &= ~(currentSlaveConfig);
- currentSlaveConfig = 0;
- currentSlave2X = false;
+ SPCR &= ~(current_slave_config);
+ current_slave_config = 0;
+ current_slave_2x = false;
}
}
diff --git a/platforms/avr/drivers/spi_master.h b/platforms/avr/drivers/spi_master.h
index 8a30f47ae4..ebbf7ddeab 100644
--- a/platforms/avr/drivers/spi_master.h
+++ b/platforms/avr/drivers/spi_master.h
@@ -41,9 +41,18 @@ typedef int16_t spi_status_t;
#ifdef __cplusplus
extern "C" {
#endif
+typedef struct spi_start_config_t {
+ pin_t slave_pin;
+ bool lsb_first;
+ uint8_t mode;
+ uint16_t divisor;
+ bool cs_active_low;
+} spi_start_config_t;
+
void spi_init(void);
bool spi_start(pin_t slavePin, bool lsbFirst, uint8_t mode, uint16_t divisor);
+bool spi_start_extended(spi_start_config_t *start_config);
spi_status_t spi_write(uint8_t data);