[PATCH] leds: separate read/write ide-disk triggers

[Michal Bozon]

here is a humble extension of leds module, adding separate
"ide-disk-read" and "ide-disk-write" triggers to existing "ide-disk"
one.

tested on pc engines ALIX.3c3 board, kernel 2.6.32, patches smoothly
current 2.6.34 as well

following scenario configures the three leds on ALIX board as
heartbeat, ide-read and ide-write indicators, respectively:

modprobe leds-alix2 force=1
modprobe ledtrig-heartbeat # not relevant to this patch
echo heartbeat > /sys/class/leds/"alix:1"/
trigger # not relevant to this patch
echo ide-disk-read > /sys/class/leds/"alix:2"/trigger
echo ide-disk-write > /sys/class/leds/"alix:3"/trigger
--- linux-source-2.6.32/drivers/ide/ide-disk.c_orig_	2010-05-17 22:11:07.000000000 +0200
+++ linux-source-2.6.32/drivers/ide/ide-disk.c	2010-05-17 22:33:41.000000000 +0200
@@ -188,6 +188,12 @@ static ide_startstop_t ide_do_rw_disk(id
 
 	ledtrig_ide_activity();
 
+	if (rq_data_dir(rq) == READ) {
+		ledtrig_ide_read_activity();
+	} else {
+		ledtrig_ide_write_activity();
+	}
+
 	pr_debug("%s: %sing: block=%llu, sectors=%u, buffer=0x%08lx\n",
 		 drive->name, rq_data_dir(rq) == READ ? "read" : "writ",
 		 (unsigned long long)block, blk_rq_sectors(rq),
--- linux-source-2.6.32/include/linux/leds.h_orig_	2010-05-17 22:29:02.000000000 +0200
+++ linux-source-2.6.32/include/linux/leds.h	2010-05-17 22:30:05.000000000 +0200
@@ -121,8 +121,12 @@ extern void led_trigger_event(struct led
 /* Trigger specific functions */
 #ifdef CONFIG_LEDS_TRIGGER_IDE_DISK
 extern void ledtrig_ide_activity(void);
+extern void ledtrig_ide_read_activity(void);
+extern void ledtrig_ide_write_activity(void);
 #else
 #define ledtrig_ide_activity() do {} while(0)
+#define ledtrig_ide_read_activity() do {} while(0)
+#define ledtrig_ide_write_activity() do {} while(0)
 #endif
 
 /*
--- linux-source-2.6.32/drivers/leds/ledtrig-ide-disk.c_orig_	2010-05-17 22:15:52.000000000 +0200
+++ linux-source-2.6.32/drivers/leds/ledtrig-ide-disk.c	2010-05-17 22:35:27.000000000 +0200
@@ -19,11 +19,21 @@
 #include <linux/leds.h>
 
 static void ledtrig_ide_timerfunc(unsigned long data);
+static void ledtrig_ide_read_timerfunc(unsigned long data);
+static void ledtrig_ide_write_timerfunc(unsigned long data);
 
 DEFINE_LED_TRIGGER(ledtrig_ide);
+DEFINE_LED_TRIGGER(ledtrig_ide_read);
+DEFINE_LED_TRIGGER(ledtrig_ide_write);
 static DEFINE_TIMER(ledtrig_ide_timer, ledtrig_ide_timerfunc, 0, 0);
+static DEFINE_TIMER(ledtrig_ide_read_timer, ledtrig_ide_read_timerfunc, 0, 0);
+static DEFINE_TIMER(ledtrig_ide_write_timer, ledtrig_ide_write_timerfunc, 0, 0);
 static int ide_activity;
 static int ide_lastactivity;
+static int ide_read_activity;
+static int ide_read_lastactivity;
+static int ide_write_activity;
+static int ide_write_lastactivity;
 
 void ledtrig_ide_activity(void)
 {
@@ -33,6 +43,22 @@ void ledtrig_ide_activity(void)
 }
 EXPORT_SYMBOL(ledtrig_ide_activity);
 
+void ledtrig_ide_read_activity(void)
+{
+	ide_read_activity++;
+	if (!timer_pending(&ledtrig_ide_read_timer))
+		mod_timer(&ledtrig_ide_read_timer, jiffies + msecs_to_jiffies(10));
+}
+EXPORT_SYMBOL(ledtrig_ide_read_activity);
+
+void ledtrig_ide_write_activity(void)
+{
+	ide_write_activity++;
+	if (!timer_pending(&ledtrig_ide_write_timer))
+		mod_timer(&ledtrig_ide_write_timer, jiffies + msecs_to_jiffies(10));
+}
+EXPORT_SYMBOL(ledtrig_ide_write_activity);
+
 static void ledtrig_ide_timerfunc(unsigned long data)
 {
 	if (ide_lastactivity != ide_activity) {
@@ -45,9 +71,35 @@ static void ledtrig_ide_timerfunc(unsign
 	}
 }
 
+static void ledtrig_ide_read_timerfunc(unsigned long data)
+{
+	if (ide_read_lastactivity != ide_read_activity) {
+		ide_read_lastactivity = ide_read_activity;
+		/* INT_MAX will set each LED to its maximum brightness */
+		led_trigger_event(ledtrig_ide_read, INT_MAX);
+		mod_timer(&ledtrig_ide_read_timer, jiffies + msecs_to_jiffies(10));
+	} else {
+		led_trigger_event(ledtrig_ide_read, LED_OFF);
+	}
+}
+
+static void ledtrig_ide_write_timerfunc(unsigned long data)
+{
+	if (ide_write_lastactivity != ide_write_activity) {
+		ide_write_lastactivity = ide_write_activity;
+		/* INT_MAX will set each LED to its maximum brightness */
+		led_trigger_event(ledtrig_ide_write, INT_MAX);
+		mod_timer(&ledtrig_ide_write_timer, jiffies + msecs_to_jiffies(10));
+	} else {
+		led_trigger_event(ledtrig_ide_write, LED_OFF);
+	}
+}
+
 static int __init ledtrig_ide_init(void)
 {
 	led_trigger_register_simple("ide-disk", &ledtrig_ide);
+	led_trigger_register_simple("ide-disk-read", &ledtrig_ide_read);
+	led_trigger_register_simple("ide-disk-write", &ledtrig_ide_write);
 	return 0;
 }