blob: f987a2bee16a8bde6137047582de72654a39e952 [file] [log] [blame]
#ifndef __SPI_BITBANG_H
#define __SPI_BITBANG_H
#include <linux/workqueue.h>
struct spi_bitbang {
struct workqueue_struct *workqueue;
struct work_struct work;
spinlock_t lock;
struct list_head queue;
u8 busy;
u8 use_dma;
u8 flags; /* extra spi->mode support */
struct spi_master *master;
/* setup_transfer() changes clock and/or wordsize to match settings
* for this transfer; zeroes restore defaults from spi_device.
int (*setup_transfer)(struct spi_device *spi,
struct spi_transfer *t);
void (*chipselect)(struct spi_device *spi, int is_on);
#define BITBANG_CS_ACTIVE 1 /* normally nCS, active low */
/* txrx_bufs() may handle dma mapping for transfers that don't
* already have one (transfer.{tx,rx}_dma is zero), or use PIO
int (*txrx_bufs)(struct spi_device *spi, struct spi_transfer *t);
/* txrx_word[SPI_MODE_*]() just looks like a shift register */
u32 (*txrx_word[4])(struct spi_device *spi,
unsigned nsecs,
u32 word, u8 bits);
/* you can call these default bitbang->master methods from your custom
* methods, if you like.
extern int spi_bitbang_setup(struct spi_device *spi);
extern void spi_bitbang_cleanup(struct spi_device *spi);
extern int spi_bitbang_transfer(struct spi_device *spi, struct spi_message *m);
extern int spi_bitbang_setup_transfer(struct spi_device *spi,
struct spi_transfer *t);
/* start or stop queue processing */
extern int spi_bitbang_start(struct spi_bitbang *spi);
extern int spi_bitbang_stop(struct spi_bitbang *spi);
#endif /* __SPI_BITBANG_H */