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authorIlya Yanok <yanok@emcraft.com>2010-09-09 23:03:32 +0200
committerWolfgang Denk <wd@denx.de>2010-10-12 22:44:33 +0200
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led_display: split led display support into generic and hw-dependent parts
Split the display command into generic interface and hardware-specific realization for PDSP188x LED display found on hmi1001 and manroland boards. Simple interface for LED displays is defined in include/led-display.h and described in doc/README.LED_display. Driver-specific implementation was moved into drivers/misc/pdsp188x.c file (enabled with CONFIG_PDSP188x set). Signed-off-by: Ilya Yanok <yanok@emcraft.com>
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+LED display internal API
+=======================================
+
+This README describes the LED display API.
+
+The API is defined by the include file include/led-display.h
+
+The first step in to define CONFIG_CMD_DISPLAY in the board config file.
+Then you need to provide the following functions to access LED display:
+
+void display_set(int cmd);
+
+This function should control the state of the LED display. Argument is
+an ORed combination of the following values:
+ DISPLAY_CLEAR -- clear the display
+ DISPLAY_HOME -- set the position to the beginning of display
+ DISPLAY_MARK -- enable mark (decimal point), if implemented
+
+int display_putc(char c);
+
+This function should display it's parameter on the LED display in the
+current position. Returns the displayed character on success or -1 in
+case of failure.
+
+With this functions defined 'display' command will display it's
+arguments on the LED display (or clear the display if called without
+arguments).