Implement setbrg in amlogic/meson serial device with driver model
similar to how the meson_uart.c driver does it in Linux. Also
configure (probe) the serial device with the new reg5 register.

Signed-off-by: Edoardo Tomelleri <e.tomell@gmail.com>
Link: https://lore.kernel.org/r/20220918161701.572814-1-e.tomell@gmail.com
Acked-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>

This reverts commit c7878a0483c59c48a730123bc0f4659fd40921bf.

Since commit c7878a0483c5 ("serial: mxc: have putc use the TXFIFO"),
serial console corruption can be seen when priting inside board_init().

Revert it to avoid the regression.

Reported-by: Tim Harvey <tharvey@gateworks.com>
Signed-off-by: Fabio Estevam <festevam@denx.de>
Acked-by: Tim Harvey <tharvey@gateworks.com>

Now that all the old code is gone, rename this option. Driver model
migration is now complete.

Signed-off-by: Simon Glass <sjg@chromium.org>

This file is being removed so drop remaining references to it.

Signed-off-by: Simon Glass <sjg@chromium.org>

There is a number of users that use uclass_first_device to access the
first and (assumed) only device in uclass.

Some check the return value of uclass_first_device and also that a
device was returned which is exactly what uclass_first_device_err does.

Some are not checking that a device was returned and can potentially
crash if no device exists in the uclass. Finally there is one that
returns NULL on error either way.

Convert all of these to use uclass_first_device_err instead, the return
value will be removed from uclass_first_device in a later patch.

Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Reviewed-by: Simon Glass <sjg@chromium.org>

Changing baudrate is a sensitive operation. To ensure that U-Boot messages
printed before changing baudrate are not lost, call new U-Boot console
flush() function.

Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Simon Glass <sjg@chromium.org>

Like in all other console functions, implement also serial_flush() function
as a fallback int console flush() function.

Flush support is available only when config option CONSOLE_FLUSH_SUPPORT is
enabled. So when it is disabled then provides just empty static inline
function serial_flush().

Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Simon Glass <sjg@chromium.org>

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>

The baud clock on some platform may change due to assigned-clock-parent
set in DT. In current flow the baud clock is only retrieved during probe
stage. If the parent of the source clock changes after probe stage, the
setbrg will set wrong baudrate.

To get the right clock rate, this patch records the baud clk struct to the
driver's priv, and changes the driver's flow to get the clock rate before
calling _mtk_serial_setbrg().

Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Daniel Golle <daniel@makrotopia.org>
Signed-off-by: Weijie Gao <weijie.gao@mediatek.com>