dahdi-linux/drivers/dahdi/wcxb_spi.h

116 lines
2.7 KiB
C

/*
* wcxb SPI library
*
* Copyright (C) 2013 Digium, Inc.
*
* All rights reserved.
*
*/
/*
* See http://www.asterisk.org for more information about
* the Asterisk project. Please do not directly contact
* any of the maintainers of this project for assistance;
* the project provides a web site, mailing lists and IRC
* channels for your use.
*
* This program is free software, distributed under the terms of
* the GNU General Public License Version 2 as published by the
* Free Software Foundation. See the LICENSE file included with
* this program for more details.
*/
#ifndef __WCXB_SPI_H
#define __WCXB_SPI_H
#include <linux/spi/spi.h>
struct wcxb_spi_transfer {
const void *tx_buf;
void *rx_buf;
u32 len:16;
u16 delay_usecs;
struct list_head node;
};
struct wcxb_spi_message {
struct list_head transfers;
struct list_head node;
struct wcxb_spi_device *spi;
void (*complete)(void *arg);
void *arg;
int status;
};
struct wcxb_spi_master;
struct wcxb_spi_device {
struct wcxb_spi_master *master;
u16 chip_select;
};
extern struct wcxb_spi_master *wcxb_spi_master_create(struct device *parent,
void __iomem *base, bool auto_cs);
extern void wcxb_spi_master_destroy(struct wcxb_spi_master *master);
extern int wcxb_spi_sync(struct wcxb_spi_device *spi,
struct wcxb_spi_message *message);
extern int wcxb_spi_async(struct wcxb_spi_device *spi,
struct wcxb_spi_message *message);
extern void wcxb_spi_handle_interrupt(struct wcxb_spi_master *master);
static inline struct wcxb_spi_device *
wcxb_spi_device_create(struct wcxb_spi_master *master, u16 chip_select)
{
struct wcxb_spi_device *spi = kzalloc(sizeof(*spi), GFP_KERNEL);
if (!spi)
return NULL;
spi->master = master;
spi->chip_select = chip_select;
return spi;
}
static inline void wcxb_spi_device_destroy(struct wcxb_spi_device *spi)
{
kfree(spi);
}
static inline void wcxb_spi_message_init(struct wcxb_spi_message *m)
{
memset(m, 0, sizeof(*m));
INIT_LIST_HEAD(&m->transfers);
}
static inline void wcxb_spi_message_add_tail(struct wcxb_spi_transfer *t,
struct wcxb_spi_message *m)
{
list_add_tail(&t->node, &m->transfers);
}
static inline int
wcxb_spi_write(struct wcxb_spi_device *spi, const void *buffer, size_t len)
{
struct wcxb_spi_transfer t = {
.tx_buf = buffer,
.len = len,
};
struct wcxb_spi_message m;
wcxb_spi_message_init(&m);
wcxb_spi_message_add_tail(&t, &m);
return wcxb_spi_sync(spi, &m);
}
static inline int
wcxb_spi_read(struct wcxb_spi_device *spi, void *buffer, size_t len)
{
struct wcxb_spi_transfer t = {
.rx_buf = buffer,
.len = len,
};
struct wcxb_spi_message m;
wcxb_spi_message_init(&m);
wcxb_spi_message_add_tail(&t, &m);
return wcxb_spi_sync(spi, &m);
}
#endif