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authorJoel Challis <git@zvecr.com>2021-08-17 23:43:09 +0100
committerGitHub <noreply@github.com>2021-08-17 23:43:09 +0100
commit1bb7af4d446174b7181c9bb22dbd14c93642ea10 (patch)
tree894eceeb29cc2c00f6b0f08a4ca177da7f172424 /platforms/avr/drivers/spi_master.c
parent483691dd73e5260fac958c524e0a12e705db43f6 (diff)
Relocate platform specific drivers (#13894)
* Relocate platform specific drivers * Move stm eeprom * Tidy up slightly
Diffstat (limited to 'platforms/avr/drivers/spi_master.c')
-rw-r--r--platforms/avr/drivers/spi_master.c180
1 files changed, 180 insertions, 0 deletions
diff --git a/platforms/avr/drivers/spi_master.c b/platforms/avr/drivers/spi_master.c
new file mode 100644
index 0000000000..4e8fd3bcdf
--- /dev/null
+++ b/platforms/avr/drivers/spi_master.c
@@ -0,0 +1,180 @@
+/* Copyright 2020
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include "spi_master.h"
+
+#include "timer.h"
+
+#if defined(__AVR_AT90USB162__) || defined(__AVR_ATmega16U2__) || defined(__AVR_ATmega32U2__) || defined(__AVR_ATmega16U4__) || defined(__AVR_ATmega32U4__) || defined(__AVR_AT90USB646__) || defined(__AVR_AT90USB647__) || defined(__AVR_AT90USB1286__) || defined(__AVR_AT90USB1287__)
+# define SPI_SCK_PIN B1
+# define SPI_MOSI_PIN B2
+# define SPI_MISO_PIN B3
+#elif defined(__AVR_ATmega32A__)
+# define SPI_SCK_PIN B7
+# define SPI_MOSI_PIN B5
+# define SPI_MISO_PIN B6
+#elif defined(__AVR_ATmega328P__) || defined(__AVR_ATmega328__)
+# define SPI_SCK_PIN B5
+# define SPI_MOSI_PIN B3
+# 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;
+
+void spi_init(void) {
+ writePinHigh(SPI_SS_PIN);
+ setPinOutput(SPI_SCK_PIN);
+ setPinOutput(SPI_MOSI_PIN);
+ setPinInput(SPI_MISO_PIN);
+
+ SPCR = (_BV(SPE) | _BV(MSTR));
+}
+
+bool spi_start(pin_t slavePin, bool lsbFirst, uint8_t mode, uint16_t divisor) {
+ if (currentSlavePin != NO_PIN || slavePin == NO_PIN) {
+ return false;
+ }
+
+ currentSlaveConfig = 0;
+
+ if (lsbFirst) {
+ currentSlaveConfig |= _BV(DORD);
+ }
+
+ switch (mode) {
+ case 1:
+ currentSlaveConfig |= _BV(CPHA);
+ break;
+ case 2:
+ currentSlaveConfig |= _BV(CPOL);
+ break;
+ case 3:
+ currentSlaveConfig |= (_BV(CPOL) | _BV(CPHA));
+ break;
+ }
+
+ 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) {
+ SPDR = data;
+
+ uint16_t timeout_timer = timer_read();
+ while (!(SPSR & _BV(SPIF))) {
+ if ((timer_read() - timeout_timer) >= SPI_TIMEOUT) {
+ return SPI_STATUS_TIMEOUT;
+ }
+ }
+
+ return SPDR;
+}
+
+spi_status_t spi_read() {
+ SPDR = 0x00; // Dummy
+
+ uint16_t timeout_timer = timer_read();
+ while (!(SPSR & _BV(SPIF))) {
+ 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) {
+ spi_status_t status;
+
+ for (uint16_t i = 0; i < length; i++) {
+ status = spi_write(data[i]);
+
+ if (status < 0) {
+ return status;
+ }
+ }
+
+ return SPI_STATUS_SUCCESS;
+}
+
+spi_status_t spi_receive(uint8_t *data, uint16_t length) {
+ spi_status_t status;
+
+ for (uint16_t i = 0; i < length; i++) {
+ status = spi_read();
+
+ if (status >= 0) {
+ data[i] = status;
+ } else {
+ return status;
+ }
+ }
+
+ return SPI_STATUS_SUCCESS;
+}
+
+void spi_stop(void) {
+ if (currentSlavePin != NO_PIN) {
+ setPinOutput(currentSlavePin);
+ writePinHigh(currentSlavePin);
+ currentSlavePin = NO_PIN;
+ SPSR &= ~(_BV(SPI2X));
+ SPCR &= ~(currentSlaveConfig);
+ currentSlaveConfig = 0;
+ currentSlave2X = false;
+ }
+}