serial: tegra: add serial driver

NVIDIA's Tegra has multiple UART controller which supports:
- APB DMA based controller fifo read/write.
- End Of Data interrupt in incoming data to know whether end
  of frame achieve or not.
- HW controlled RTS and CTS flow control to reduce SW overhead.

Add serial driver to use all above feature.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 11 insertions, 0 deletions

diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index 59c23d038106..aff3cd356662 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -269,6 +269,17 @@ config SERIAL_SIRFSOC_CONSOLE
           your boot loader about how to pass options to the kernel at
           boot time.)
 
+config SERIAL_TEGRA
+        tristate "NVIDIA Tegra20/30 SoC serial controller"
+        depends on ARCH_TEGRA && TEGRA20_APB_DMA
+        select SERIAL_CORE
+        help
+          Support for the on-chip UARTs on the NVIDIA Tegra series SOCs
+          providing /dev/ttyHS0, 1, 2, 3 and 4 (note, some machines may not
+          provide all of these ports, depending on how the serial port
+          are enabled). This driver uses the APB DMA to achieve higher baudrate
+          and better performance.
+
 config SERIAL_MAX3100
         tristate "MAX3100 support"
         depends on SPI