diff options
Diffstat (limited to 'firmware/drivers')
| -rw-r--r-- | firmware/drivers/wm8523.c | 126 | ||||
| -rw-r--r-- | firmware/drivers/wm8523.h | 33 |
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__*/ |