parisc: led: Rewrite LED/LCD driver to utilizize Linux LED subsystem

Rewrite the whole driver and drop the own code to calculate load
average, disk and LAN load. Switch instead to use the in-kernel LED
subsystem, which gives us quite some advantages, e.g.
- existing triggers for heartbeat and disk/lan activity can be used
- users can configre the LEDs at will to any existing trigger via
  /sys/class/leds
- less overhead since we don't need to run own timers
- fully integrated in Linux and as such cleaner code.

Note that the driver now depends on CONFIG_LEDS_CLASS which has to
be built-in and not as module.
Signed-off-by: Helge Deller <deller@gmx.de>

arch/parisc/include/asm/led.h

@@ -25,16 +25,13 @@
 #define LED_CMD_REG_NONE 0		/* NULL == no addr for the cmd register */
 
 /* register_led_driver() */
-int __init register_led_driver(int model, unsigned long cmd_reg, unsigned long data_reg);
+int register_led_driver(int model, unsigned long cmd_reg, unsigned long data_reg);
 
 #ifdef CONFIG_CHASSIS_LCD_LED
 /* writes a string to the LCD display (if possible on this h/w) */
-int lcd_print(const char *str);
+void lcd_print(const char *str);
 #else
-#define lcd_print(str)
+#define lcd_print(str) do { } while (0)
 #endif
 
-/* main LED initialization function (uses PDC) */ 
-int __init led_init(void);
-
 #endif /* LED_H */

arch/parisc/kernel/setup.c

@@ -143,11 +143,6 @@ void __init setup_arch(char **cmdline_p)
 	parisc_cache_init();
 	paging_init();
 
-#ifdef CONFIG_CHASSIS_LCD_LED
-	/* initialize the LCD/LED after boot_cpu_data is available ! */
-	led_init();		/* LCD/LED initialization */
-#endif
-
 #ifdef CONFIG_PA11
 	dma_ops_init();
 #endif

drivers/parisc/Kconfig

@@ -100,8 +100,9 @@ config SUPERIO
 
 config CHASSIS_LCD_LED
 	bool "Chassis LCD and LED support"
+	depends on LEDS_CLASS=y
 	default y
-	select VM_EVENT_COUNTERS
+	select LEDS_TRIGGERS
 	help
 	  Say Y here if you want to enable support for the Heartbeat,
 	  Disk/Network activities LEDs on some PA-RISC machines,