mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-11-16 09:48:16 +00:00
79267edd10
Move all of the status LED feature to drivers/led/Kconfig. doc/README.LED updated to reflect the Kconfig implementation. Tested boards: CL-SOM-AM57x, CM-T335 Signed-off-by: Uri Mashiach <uri.mashiach@compulab.co.il>
78 lines
2.4 KiB
Text
78 lines
2.4 KiB
Text
Status LED
|
|
========================================
|
|
|
|
This README describes the status LED API.
|
|
|
|
The API is defined by the include file include/status_led.h
|
|
|
|
The first step is to enable CONFIG_LED_STATUS in menuconfig:
|
|
> Device Drivers > LED Support.
|
|
|
|
If the LED support is only for specific board, enable
|
|
CONFIG_LED_STATUS_BOARD_SPECIFIC in the menuconfig.
|
|
|
|
Status LEDS 0 to 5 are enabled by the following configurations at menuconfig:
|
|
CONFIG_STATUS_LED0, CONFIG_STATUS_LED1, ... CONFIG_STATUS_LED5
|
|
|
|
The following should be configured for each of the enabled LEDs:
|
|
CONFIG_STATUS_LED_BIT<n>
|
|
CONFIG_STATUS_LED_STATE<n>
|
|
CONFIG_STATUS_LED_FREQ<n>
|
|
Where <n> is an integer 1 through 5 (empty for 0).
|
|
|
|
CONFIG_STATUS_LED_BIT is passed into the __led_* functions to identify which LED
|
|
is being acted on. As such, the value choose must be unique with with respect to
|
|
the other CONFIG_STATUS_LED_BIT's. Mapping the value to a physical LED is the
|
|
reponsiblity of the __led_* function.
|
|
|
|
CONFIG_STATUS_LED_STATE is the initial state of the LED. It should be set to one
|
|
of these values: CONFIG_LED_STATUS_OFF or CONFIG_LED_STATUS_ON.
|
|
|
|
CONFIG_STATUS_LED_FREQ determines the LED blink frequency.
|
|
Values range from 2 to 10.
|
|
|
|
Some other LED macros
|
|
---------------------
|
|
|
|
CONFIG_STATUS_LED_BOOT is the LED to light when the board is booting.
|
|
This must be a valid LED number (0-5).
|
|
|
|
CONFIG_STATUS_LED_RED is the red LED. It is used to signal errors. This must be
|
|
a valid LED number (0-5). Other similar color LED's macros are
|
|
CONFIG_STATUS_LED_GREEN, CONFIG_STATUS_LED_YELLOW and CONFIG_STATUS_LED_BLUE.
|
|
|
|
General LED functions
|
|
---------------------
|
|
The following functions should be defined:
|
|
|
|
__led_init is called once to initialize the LED to CONFIG_STATUS_LED_STATE.
|
|
One time start up code should be placed here.
|
|
|
|
__led_set is called to change the state of the LED.
|
|
|
|
__led_toggle is called to toggle the current state of the LED.
|
|
|
|
Colour LED
|
|
========================================
|
|
|
|
Colour LED's are at present only used by ARM.
|
|
|
|
The functions names explain their purpose.
|
|
|
|
coloured_LED_init
|
|
red_LED_on
|
|
red_LED_off
|
|
green_LED_on
|
|
green_LED_off
|
|
yellow_LED_on
|
|
yellow_LED_off
|
|
blue_LED_on
|
|
blue_LED_off
|
|
|
|
These are weakly defined in arch/arm/lib/board.c to noops. Where applicable, define
|
|
these functions in the board specific source.
|
|
|
|
TBD : Describe older board dependent macros similar to what is done for
|
|
CONFIG_TQM8xxL.
|
|
|
|
TBD : Describe general support via asm/status_led.h
|