/*
* Copyright (c) 2016 embedded brains GmbH. All rights reserved.
*
* embedded brains GmbH
* Dornierstr. 4
* 82178 Puchheim
* Germany
* <info@embedded-brains.de>
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.org/license/LICENSE.
*/
#include <dev/serial/sc16is752.h>
#include <assert.h>
#include <fcntl.h>
#include <inttypes.h>
#include <unistd.h>
#include <dev/spi/spi.h>
#include "sc16is752-regs.h"
static void msg_init(
struct spi_ioc_transfer *msg,
uint8_t cs,
uint32_t speed,
size_t len,
uint8_t *rx_buf,
const uint8_t *tx_buf
)
{
msg->rx_buf = rx_buf;
msg->tx_buf = tx_buf;
msg->len = len;
msg->speed_hz = speed;
msg->delay_usecs = 1;
msg->bits_per_word = 8;
msg->cs_change = 0;
msg->rx_nbits = 0;
msg->tx_nbits = 0;
msg->mode = 0;
msg->cs = cs;
}
static int sc16is752_spi_write_reg(
sc16is752_context *base,
uint8_t addr,
const uint8_t *data,
size_t len
)
{
sc16is752_spi_context *ctx = (sc16is752_spi_context *) base;
spi_ioc_transfer msg[2];
uint8_t unused[SC16IS752_FIFO_DEPTH];
uint8_t tx_cmd;
_Assert(len < RTEMS_ARRAY_SIZE(unused));
msg_init(&msg[0], ctx->cs, ctx->speed_hz, 1, &unused[0], &tx_cmd);
msg_init(&msg[1], ctx->cs, ctx->speed_hz, len, &unused[0], &data[0]);
tx_cmd = addr << 3;
msg[1].cs_change = 1;
return ioctl(ctx->fd, SPI_IOC_MESSAGE(2), &msg[0]);
}
static int sc16is752_spi_read_reg(
sc16is752_context *base,
uint8_t addr,
uint8_t *data,
size_t len
)
{
sc16is752_spi_context *ctx = (sc16is752_spi_context *) base;
spi_ioc_transfer msg[2];
uint8_t unused;
uint8_t tx_cmd;
uint8_t tx_buf[SC16IS752_FIFO_DEPTH];
_Assert(len < RTEMS_ARRAY_SIZE(tx_buf));
msg_init(&msg[0], ctx->cs, ctx->speed_hz, 1, &unused, &tx_cmd);
msg_init(&msg[1], ctx->cs, ctx->speed_hz, len, &data[0], &tx_buf[0]);
tx_cmd = 0x80 | (addr << 3);
msg[1].cs_change = 1;
return ioctl(ctx->fd, SPI_IOC_MESSAGE(2), &msg[0]);
}
static int sc16is752_spi_read_2_reg(
sc16is752_context *base,
uint8_t addr_0,
uint8_t addr_1,
uint8_t data[2]
)
{
sc16is752_spi_context *ctx = (sc16is752_spi_context *) base;
spi_ioc_transfer msg[4];
uint8_t unused;
uint8_t tx_cmd_0;
uint8_t tx_cmd_1;
msg_init(&msg[0], ctx->cs, ctx->speed_hz, 1, &unused, &tx_cmd_0);
msg_init(&msg[1], ctx->cs, ctx->speed_hz, 1, &data[0], &unused);
msg_init(&msg[2], ctx->cs, ctx->speed_hz, 1, &unused, &tx_cmd_1);
msg_init(&msg[3], ctx->cs, ctx->speed_hz, 1, &data[1], &unused);
tx_cmd_0 = 0x80 | (addr_0 << 3);
tx_cmd_1 = 0x80 | (addr_1 << 3);
msg[1].cs_change = 1;
msg[3].cs_change = 1;
return ioctl(ctx->fd, SPI_IOC_MESSAGE(4), &msg[0]);
}
static bool sc16is752_spi_first_open(sc16is752_context *base)
{
sc16is752_spi_context *ctx = (sc16is752_spi_context *) base;
ctx->fd = open(ctx->spi_path, O_RDWR);
return ctx->fd >= 0;
}
static void sc16is752_spi_last_close(sc16is752_context *base)
{
sc16is752_spi_context *ctx = (sc16is752_spi_context *) base;
close(ctx->fd);
}
rtems_status_code sc16is752_spi_create(
sc16is752_spi_context *ctx,
const char *device_path
)
{
ctx->base.write_reg = sc16is752_spi_write_reg;
ctx->base.read_reg = sc16is752_spi_read_reg;
ctx->base.read_2_reg = sc16is752_spi_read_2_reg;
ctx->base.first_open = sc16is752_spi_first_open;
ctx->base.last_close = sc16is752_spi_last_close;
return rtems_termios_device_install(
device_path,
&sc16is752_termios_handler,
NULL,
&ctx->base.base
);
}