On most Renesas ARM platforms, the SCIF serial ports can be used with DMA, so most users will want DMA support to be enabled.
On SuperH platforms, SCI(F) serial ports cannot be used with DMA yet (see also commit 219fb0c1436e4893 ("serial: sh-sci: Remove the platform data dma slave rx/tx channel IDs")), so users will want it disabled to reduce kernel size. Hence follow the above rationale to configure the default, unless CONFIG_EXPERT is enabled. Signed-off-by: Geert Uytterhoeven <geert+rene...@glider.be> --- drivers/tty/serial/Kconfig | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig index 952a2c6a9da08fdd..4e6dfb0a762b5807 100644 --- a/drivers/tty/serial/Kconfig +++ b/drivers/tty/serial/Kconfig @@ -781,8 +781,9 @@ config SERIAL_SH_SCI_EARLYCON default ARCH_RENESAS || H8300 config SERIAL_SH_SCI_DMA - bool "DMA support" + bool "DMA support" if EXPERT depends on SERIAL_SH_SCI && DMA_ENGINE + default ARCH_RENESAS config SERIAL_PNX8XXX bool "Enable PNX8XXX SoCs' UART Support" -- 2.7.4