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-rw-r--r--firmware/drivers/wm8523.c126
-rw-r--r--firmware/drivers/wm8523.h33
2 files changed, 159 insertions, 0 deletions
diff --git a/firmware/drivers/wm8523.c b/firmware/drivers/wm8523.c
new file mode 100644
index 0000000..36d293a
--- /dev/null
+++ b/firmware/drivers/wm8523.c
@@ -0,0 +1,126 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/***************************************************************************
+ * wm8523.c
+ *
+ * Tue Jun 4 20:47:15 CEST 2013
+ * Copyright 2013 Bent Bisballe Nyeng
+ * deva@aasimon.org
+ ****************************************************************************/
+
+/*
+ * This file is part of Pedal2Metal.
+ *
+ * Pedal2Metal 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 2 of the License, or
+ * (at your option) any later version.
+ *
+ * Pedal2Metal 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 Pedal2Metal; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+#include "wm8523.h"
+
+#include <string.h>
+#include <lpc17xx_spi.h>
+
+#define WM8523_WRITE 0
+#define WM8523_READ 1
+
+static SPI_CFG_Type spi_cfg;
+static LPC_SPI_TypeDef spi;
+
+typedef struct __attribute__ ((packed)) {
+ uint8_t rw:1; ///< See WM8523_WRITE and WM8523_READ
+ uint8_t reg:7; ///< See page 35 in the WM8523 manual.
+ uint16_t data;
+} WM8523_transfer_t;
+
+void WM8523_Init()
+{
+ // 16 bit data tranfers
+ spi_cfg.Databit = SPI_DATABIT_16;
+
+ // WM8523 samples bits on rising edges. Mode 0 or 3 will work
+ // http://en.wikipedia.org/wiki/Serial_Peripheral_Interface_Bus#Clock_polarity_and_phase
+
+ // Mode 0
+ spi_cfg.CPHA = SPI_CPHA_FIRST; // 0
+ spi_cfg.CPOL = SPI_CPOL_HI; // 0
+ /*
+ // Mode 3
+ spi_cfg.CPHA = SPI_CPHA_SECOND; // 1
+ spi_cfg.CPOL = SPI_CPOL_LO; // 1
+ */
+
+ // We are the master
+ spi_cfg.Mode = SPI_MASTER_MODE;
+
+ // We run on a little endian mcu.
+ spi_cfg.DataOrder = SPI_DATA_LSB_FIRST;
+
+ // Se WM8523 manual page 14. Min clock pulse width 40ns ~= 25MHz
+ spi_cfg.ClockRate = 1000000000; // 1MHz
+
+ SPI_Init(&spi, &spi_cfg);
+}
+
+static volatile int spi_done = 0;
+void spi_mark_as_done()
+{
+ spi_done = 1;
+}
+
+static void send(void *data, size_t size)
+{
+ SPI_DATA_SETUP_Type dst;
+ memset(&dst, 0, sizeof(dst));
+ dst.rx_data = data;
+ dst.length = size;
+ dst.callback = spi_mark_as_done;
+
+ spi_done = 0;
+ SPI_ReadWrite(&spi, &dst, SPI_TRANSFER_INTERRUPT);
+
+ while(!spi_done) {}
+}
+
+static void receive(void *data, size_t size)
+{
+ // http://anhnvnguyen.blogspot.dk/2010/04/lpc17xx-gpio-basic_05.html
+ // TODO: set SSEL0 low
+ // PINSEL3[13:12] = p1.21 (SSEL0)
+ LPC_PINCON->PINSEL3 &= ~((1<<13)|(1<<12)); // set to 00
+
+ SPI_DATA_SETUP_Type dst;
+ memset(&dst, 0, sizeof(dst));
+ dst.tx_data = data;
+ dst.length = size;
+ dst.callback = spi_mark_as_done;
+
+ spi_done = 0;
+ SPI_ReadWrite(&spi, &dst, SPI_TRANSFER_INTERRUPT);
+
+ while(!spi_done) {}
+
+ // TODO: set SSEL0 high
+}
+
+/**
+Volume update registers R06h and R07h are unavailable in SPI control mode.
+To use volume update in software control mode, I2C mode must be used.
+*/
+void WM8523_Configure()
+{
+ WM8523_transfer_t transfer;
+ transfer.rw = WM8523_READ;
+ transfer.reg = 0; // R0 read version : 0x8523
+ transfer.data = 0;
+ //send(&transfer, sizeof(transfer));
+ receive(&transfer, sizeof(transfer));
+}
diff --git a/firmware/drivers/wm8523.h b/firmware/drivers/wm8523.h
new file mode 100644
index 0000000..085b1f4
--- /dev/null
+++ b/firmware/drivers/wm8523.h
@@ -0,0 +1,33 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/***************************************************************************
+ * wm8523.h
+ *
+ * Tue Jun 4 20:47:15 CEST 2013
+ * Copyright 2013 Bent Bisballe Nyeng
+ * deva@aasimon.org
+ ****************************************************************************/
+
+/*
+ * This file is part of Pedal2Metal.
+ *
+ * Pedal2Metal 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 2 of the License, or
+ * (at your option) any later version.
+ *
+ * Pedal2Metal 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 Pedal2Metal; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+#ifndef __PEDAL2METAL_WM8523_H__
+#define __PEDAL2METAL_WM8523_H__
+
+void WM8523_Init();
+void WM8523_Configure();
+
+#endif/*__PEDAL2METAL_WM8523_H__*/