mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-11-12 16:07:30 +00:00
e101550a9a
Implements the tstc() interface for the serial driver. Multiplexing the console between the serial port and a keyboard uses a polling method of checking if characters are available; this means that the serial console must be non-blocking when attempting to read characters. Signed-off-by: Taylor Hutt <thutt@chromium.org> Signed-off-by: Simon Glass <sjg@chromium.org>
118 lines
2.8 KiB
C
118 lines
2.8 KiB
C
/*
|
|
* Copyright (c) 2011 The Chromium OS Authors.
|
|
* See file CREDITS for list of people who contributed to this
|
|
* project.
|
|
*
|
|
* 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 program 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 this program; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
|
|
* MA 02111-1307 USA
|
|
*/
|
|
|
|
/*
|
|
* This provide a test serial port. It provides an emulated serial port where
|
|
* a test program and read out the serial output and inject serial input for
|
|
* U-Boot.
|
|
*/
|
|
|
|
#include <common.h>
|
|
#include <os.h>
|
|
#include <serial.h>
|
|
#include <linux/compiler.h>
|
|
|
|
/*
|
|
*
|
|
* serial_buf: A buffer that holds keyboard characters for the
|
|
* Sandbox U-boot.
|
|
*
|
|
* invariants:
|
|
* serial_buf_write == serial_buf_read -> empty buffer
|
|
* (serial_buf_write + 1) % 16 == serial_buf_read -> full buffer
|
|
*/
|
|
static char serial_buf[16];
|
|
static unsigned int serial_buf_write;
|
|
static unsigned int serial_buf_read;
|
|
|
|
static int sandbox_serial_init(void)
|
|
{
|
|
os_tty_raw(0);
|
|
return 0;
|
|
}
|
|
|
|
static void sandbox_serial_setbrg(void)
|
|
{
|
|
}
|
|
|
|
static void sandbox_serial_putc(const char ch)
|
|
{
|
|
os_write(1, &ch, 1);
|
|
}
|
|
|
|
static void sandbox_serial_puts(const char *str)
|
|
{
|
|
os_write(1, str, strlen(str));
|
|
}
|
|
|
|
static unsigned int increment_buffer_index(unsigned int index)
|
|
{
|
|
return (index + 1) % ARRAY_SIZE(serial_buf);
|
|
}
|
|
|
|
static int sandbox_serial_tstc(void)
|
|
{
|
|
const unsigned int next_index =
|
|
increment_buffer_index(serial_buf_write);
|
|
ssize_t count;
|
|
|
|
os_usleep(100);
|
|
if (next_index == serial_buf_read)
|
|
return 1; /* buffer full */
|
|
|
|
count = os_read_no_block(0, &serial_buf[serial_buf_write], 1);
|
|
if (count == 1)
|
|
serial_buf_write = next_index;
|
|
return serial_buf_write != serial_buf_read;
|
|
}
|
|
|
|
static int sandbox_serial_getc(void)
|
|
{
|
|
int result;
|
|
|
|
while (!sandbox_serial_tstc())
|
|
; /* buffer empty */
|
|
|
|
result = serial_buf[serial_buf_read];
|
|
serial_buf_read = increment_buffer_index(serial_buf_read);
|
|
return result;
|
|
}
|
|
|
|
static struct serial_device sandbox_serial_drv = {
|
|
.name = "sandbox_serial",
|
|
.start = sandbox_serial_init,
|
|
.stop = NULL,
|
|
.setbrg = sandbox_serial_setbrg,
|
|
.putc = sandbox_serial_putc,
|
|
.puts = sandbox_serial_puts,
|
|
.getc = sandbox_serial_getc,
|
|
.tstc = sandbox_serial_tstc,
|
|
};
|
|
|
|
void sandbox_serial_initialize(void)
|
|
{
|
|
serial_register(&sandbox_serial_drv);
|
|
}
|
|
|
|
__weak struct serial_device *default_serial_console(void)
|
|
{
|
|
return &sandbox_serial_drv;
|
|
}
|