msp430fr: rename spi_b to spi to be consistent with other architectures

1 files changed, 75 insertions, 0 deletions

diff --git a/src/arch/msp430fr5994lp/driver/spi.cc b/src/arch/msp430fr5994lp/driver/spi.cc
new file mode 100644
index 0000000..543987d
--- /dev/null
+++ b/src/arch/msp430fr5994lp/driver/spi.cc
@@ -0,0 +1,75 @@
+#include "driver/spi.h"
+#include <msp430.h>
+
+#ifndef F_I2C
+#define F_I2C 1000000UL
+#endif
+
+void SPI::setup()
+{
+	UCB1CTLW0 |= UCSWRST;
+
+	/* UCB1CLK Pin 5.2 */
+	P5SEL1 &= ~BIT2;
+	P5SEL0 |= BIT2;
+	P5DIR |= BIT2;
+
+	/* UCB1SIMO Pin 5.0 */
+	P5SEL1 &= ~BIT0;
+	P5SEL0 |= BIT0;
+	P5DIR |= BIT0;
+
+	/* UCB1SOMI Pin 5.1 */
+	P5SEL1 &= ~BIT1;
+	P5SEL0 |= BIT1;
+	P5DIR &= ~BIT1;
+	//P1REN |= BIT6;
+
+	UCB1CTLW0 = UCCKPH | UCMSB | UCMST | UCSYNC | UCMODE_0 | UCSSEL__SMCLK | UCSWRST;
+	UCB1BRW = (F_CPU/F_I2C)-1; // /16 -> 1MHz
+	// UCB1BRW = (F_CPU / F_I2C) - 1
+	UCB1CTLW0 &= ~UCSWRST;
+}
+
+static inline unsigned char clean_rxbuf()
+{
+	return UCB1RXBUF;
+}
+
+signed char SPI::xmit(unsigned char tx_len, unsigned char *tx_buf,
+		unsigned char rx_len, unsigned char *rx_buf)
+{
+	if (tx_len < 1) {
+		return -1;
+	}
+
+	while (UCB1STATW & UCBUSY) ;
+
+	if (!(UCB1IFG & UCTXIFG)) {
+		return -1;
+	}
+
+	UCB1IFG &= ~UCRXIFG;
+	UCB1TXBUF = tx_buf[0];
+
+	unsigned char tx_pos = 1;
+	unsigned char rx_pos = 0;
+
+	while (tx_pos < tx_len || rx_pos < rx_len) {
+		if ((tx_pos < tx_len) && (UCB1IFG & UCTXIFG)) {
+			UCB1TXBUF = tx_buf[tx_pos++];
+		}
+		if (UCB1IFG & UCRXIFG) {
+			if (rx_pos < rx_len) {
+				rx_buf[rx_pos] = UCB1RXBUF;
+			} else {
+				UCB1IFG &= ~UCRXIFG;
+			}
+			rx_pos++;
+		}
+	}
+	while (UCB1STATW & UCBUSY) ;
+	return 0;
+}
+
+SPI spi;