rockbox/firmware/target/arm/imx31/spi-imx31.h
2010-05-18 23:50:00 +00:00

89 lines
3 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (c) 2007 Will Robertson
*
* 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 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#ifndef SPI_IMX31_H
#define SPI_IMX31_H
#define USE_CSPI1_MODULE (1 << 0)
#define USE_CSPI2_MODULE (1 << 1)
#define USE_CSPI3_MODULE (1 << 2)
/* SPI_MODULE_MASK is set in target's config */
enum spi_module_number
{
__CSPI_NUM_START = -1, /* The first will be 0 */
#if (SPI_MODULE_MASK & USE_CSPI1_MODULE)
CSPI1_NUM,
#endif
#if (SPI_MODULE_MASK & USE_CSPI2_MODULE)
CSPI2_NUM,
#endif
#if (SPI_MODULE_MASK & USE_CSPI3_MODULE)
CSPI3_NUM,
#endif
SPI_NUM_CSPI,
};
struct spi_node
{
enum spi_module_number num; /* Module number (CSPIx_NUM) */
unsigned long conreg; /* CSPI conreg setup */
unsigned long periodreg; /* CSPI periodreg setup */
};
struct spi_transfer_desc;
typedef void (*spi_transfer_cb_fn_type)(struct spi_transfer_desc *);
struct spi_transfer_desc
{
const struct spi_node *node; /* node for this transfer */
const void *txbuf; /* buffer to transmit */
void *rxbuf; /* buffer to receive */
int count; /* number of elements */
spi_transfer_cb_fn_type callback; /* function to call when done */
struct spi_transfer_desc *next; /* next transfer queued,
spi layer sets this */
};
/* NOTE: SPI updates the descrptor during the operation. Do not write
* to it until completion notification is received. If no callback is
* specified, the caller must find a way to ensure integrity.
*
* -1 will be written to 'count' if an error occurs, otherwise it will
* be zero when completed.
*/
/* One-time init of SPI driver */
void spi_init(void);
/* Enable the specified module for the node */
void spi_enable_module(const struct spi_node *node);
/* Disabled the specified module for the node */
void spi_disable_module(const struct spi_node *node);
/* Send and/or receive data on the specified node (asychronous) */
bool spi_transfer(struct spi_transfer_desc *xfer);
/* Returns 'true' if the descriptor is not busy */
bool spi_transfer_complete(const struct spi_transfer_desc *xfer);
#endif /* SPI_IMX31_H */