serial: Implement flush callback

UART drivers have putc/puts functions which just put characters into HW
transmit queue and do not wait until all data are transmitted.

Implement flush callback via serial driver's pending(false) callback which
waits until HW transmit all characters from the queue.

Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
This commit is contained in:
Pali Rohár 2022-09-05 11:31:18 +02:00 committed by Tom Rini
parent 974f48366f
commit 016e2be96d

View file

@ -238,6 +238,18 @@ static void _serial_puts(struct udevice *dev, const char *str)
} while (*str);
}
#ifdef CONFIG_CONSOLE_FLUSH_SUPPORT
static void _serial_flush(struct udevice *dev)
{
struct dm_serial_ops *ops = serial_get_ops(dev);
if (!ops->pending)
return;
while (ops->pending(dev, false) > 0)
;
}
#endif
static int __serial_getc(struct udevice *dev)
{
struct dm_serial_ops *ops = serial_get_ops(dev);
@ -398,6 +410,13 @@ static void serial_stub_puts(struct stdio_dev *sdev, const char *str)
_serial_puts(sdev->priv, str);
}
#ifdef CONFIG_CONSOLE_FLUSH_SUPPORT
static void serial_stub_flush(struct stdio_dev *sdev)
{
_serial_flush(sdev->priv);
}
#endif
static int serial_stub_getc(struct stdio_dev *sdev)
{
return _serial_getc(sdev->priv);
@ -520,6 +539,7 @@ static int serial_post_probe(struct udevice *dev)
sdev.priv = dev;
sdev.putc = serial_stub_putc;
sdev.puts = serial_stub_puts;
STDIO_DEV_ASSIGN_FLUSH(&sdev, serial_stub_flush);
sdev.getc = serial_stub_getc;
sdev.tstc = serial_stub_tstc;