Linux serial port driver - s3c6410 platform (I)

1. Kconfig analysis in the serial folder

config SERIAL_SAMSUNG 

tristate "Samsung SoC serial support"

depends on ARM && PLAT_S3C

select SERIAL_CORE

help

  Support for the on-chip UARTs on the Samsung S3C24XX series CPUs, to support Samsung's on-chip UARTs controller

  providing /dev/ttySAC0, 1 and 2 (note, some machines may not

  provide all of these ports, depending on how the serial port

  pins are configured.

config SERIAL_SAMSUNG_UARTS how many UART controllers are there

int

depends on SERIAL_SAMSUNG

default 2 if ARCH_S3C2400

default 4 if ARCH_S3C64XX || ARCH_S5P64XX || CPU_S3C2443 || ARCH_S5PC1XX

default 3

help

  Select the number of available UART ports for the Samsung S3C

  serial driver

config SERIAL_SAMSUNG_DEBUG for debugging

bool "Samsung SoC serial debug"

depends on SERIAL_SAMSUNG && DEBUG_LL

help

  Add support for debugging the serial driver. Since this is

  generally being used as a console, we use our own output

  routines that go via the low-level debug printascii()

  function.

config SERIAL_SAMSUNG_CONSOLE is used to define the serial port as a console terminal

bool "Support for console on Samsung SoC serial port"

depends on SERIAL_SAMSUNG=y

select SERIAL_CORE_CONSOLE

help

  Allow selection of the S3C24XX on-board serial ports for use as

  an virtual console.

 Even if you say Y here, the currently visible virtual console

  (/dev/tty0) will still be used as the system console by default, but

  you can alter that using a kernel command line option such as

  "console=ttySACx". (Try "man bootparam" or see the documentation of

  your boot loader about how to pass options to the kernel at

  boot time.)

config SERIAL_S3C2400 for S3C2400

tristate "Samsung S3C2410 Serial port support"

depends on ARM && SERIAL_SAMSUNG && CPU_S3C2400

default y if CPU_S3C2400

help

  Serial port support for the Samsung S3C2400 SoC

config SERIAL_S3C2410 for S3C2410

tristate "Samsung S3C2410 Serial port support"

depends on SERIAL_SAMSUNG && CPU_S3C2410

default y if CPU_S3C2410

help

  Serial port support for the Samsung S3C2410 SoC

config SERIAL_S3C2412

tristate "Samsung S3C2412/S3C2413 Serial port support"

depends on SERIAL_SAMSUNG && CPU_S3C2412

default y if CPU_S3C2412

help

  Serial port support for the Samsung S3C2412 and S3C2413 SoC

config SERIAL_S3C2440

tristate "Samsung S3C2440/S3C2442 Serial port support"

depends on SERIAL_SAMSUNG && (CPU_S3C2440 || CPU_S3C2442)

default y if CPU_S3C2440

default y if CPU_S3C2442

help

  Serial port support for the Samsung S3C2440 and S3C2442 SoC

config SERIAL_S3C24A0

tristate "Samsung S3C24A0 Serial port support"

depends on SERIAL_SAMSUNG && CPU_S3C24A0

default y if CPU_S3C24A0

help

  Serial port support for the Samsung S3C24A0 SoC

config SERIAL_S3C6400 for (CPU_S3C6400 || CPU_S3C6410 || CPU_S5P6440)

tristate "Samsung S3C6400/S3C6410/S5P6440 Serial port support"

depends on SERIAL_SAMSUNG && (CPU_S3C6400 || CPU_S3C6410 || CPU_S5P6440)

default y

help

  Serial port support for the Samsung S3C6400, S3C6410 and S5P6440

  SoCs

2. Summary of Makefile in serial folder

obj-$(CONFIG_SERIAL_CORE) += serial_core.o

obj-$(CONFIG_SERIAL_SAMSUNG) += samsung.o

obj-$(CONFIG_SERIAL_S3C2400) += s3c2400.o

obj-$(CONFIG_SERIAL_S3C2410) += s3c2410.o

obj-$(CONFIG_SERIAL_S3C2412) += s3c2412.o

obj-$(CONFIG_SERIAL_S3C2440) += s3c2440.o

obj-$(CONFIG_SERIAL_S3C24A0) += s3c24a0.o

obj-$(CONFIG_SERIAL_S3C6400) += s3c6400.o

3. Top-level .config configuration file

CONFIG_SERIAL_SAMSUNG=y

CONFIG_SERIAL_SAMSUNG_UARTS=4

# CONFIG_SERIAL_SAMSUNG_DEBUG is not set

CONFIG_SERIAL_SAMSUNG_CONSOLE=y

CONFIG_SERIAL_S3C6400=y

CONFIG_SERIAL_CORE=y

CONFIG_SERIAL_CORE_CONSOLE=y

4. From the above, we can see that the main files involved in the serial port driver are

（1）、serial_core.c

（2）、samsung.c

（3）、s3c6400.c