leds: trigger: Introduce a MTD (NAND/NOR) trigger

This commit introduces a MTD trigger for flash (NAND/NOR) device
activity. The implementation is copied from IDE disk.

This trigger deprecates the "nand-disk" LED trigger, but for backwards
compatibility, we still keep the "nand-disk" trigger around.

The motivation for deprecating the "nand-disk" LED trigger is that
it only works for NAND drivers, whereas the "mtd" LED trigger
is more generic (in fact, "nand-disk" currently only works for
certain NAND drivers).

Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>

4 files changed, 60 insertions, 0 deletions

diff --git a/drivers/leds/trigger/Kconfig b/drivers/leds/trigger/Kconfig
index 554f5bfbeced..beac8c31c51b 100644
--- a/drivers/leds/trigger/Kconfig
+++ b/drivers/leds/trigger/Kconfig
@@ -41,6 +41,14 @@ config LEDS_TRIGGER_IDE_DISK
           This allows LEDs to be controlled by IDE disk activity.
           If unsure, say Y.
 
+config LEDS_TRIGGER_MTD
+        bool "LED MTD (NAND/NOR) Trigger"
+        depends on MTD
+        depends on LEDS_TRIGGERS
+        help
+          This allows LEDs to be controlled by MTD activity.
+          If unsure, say N.
+
 config LEDS_TRIGGER_HEARTBEAT
         tristate "LED Heartbeat Trigger"
         depends on LEDS_TRIGGERS
diff --git a/drivers/leds/trigger/Makefile b/drivers/leds/trigger/Makefile
index 547bf5c80e52..8cc64a4f4e25 100644
--- a/drivers/leds/trigger/Makefile
+++ b/drivers/leds/trigger/Makefile
@@ -1,6 +1,7 @@
 obj-$(CONFIG_LEDS_TRIGGER_TIMER)        += ledtrig-timer.o
 obj-$(CONFIG_LEDS_TRIGGER_ONESHOT)      += ledtrig-oneshot.o
 obj-$(CONFIG_LEDS_TRIGGER_IDE_DISK)     += ledtrig-ide-disk.o
+obj-$(CONFIG_LEDS_TRIGGER_MTD)          += ledtrig-mtd.o
 obj-$(CONFIG_LEDS_TRIGGER_HEARTBEAT)    += ledtrig-heartbeat.o
 obj-$(CONFIG_LEDS_TRIGGER_BACKLIGHT)    += ledtrig-backlight.o
 obj-$(CONFIG_LEDS_TRIGGER_GPIO)         += ledtrig-gpio.o
diff --git a/drivers/leds/trigger/ledtrig-mtd.c b/drivers/leds/trigger/ledtrig-mtd.c
new file mode 100644
index 000000000000..99b5b0a4d826
--- /dev/null
+++ b/drivers/leds/trigger/ledtrig-mtd.c
@@ -0,0 +1,45 @@
+/*
+ * LED MTD trigger
+ *
+ * Copyright 2016 Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
+ *
+ * Based on LED IDE-Disk Activity Trigger
+ *
+ * Copyright 2006 Openedhand Ltd.
+ *
+ * Author: Richard Purdie <rpurdie@openedhand.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/leds.h>
+
+#define BLINK_DELAY 30
+
+DEFINE_LED_TRIGGER(ledtrig_mtd);
+DEFINE_LED_TRIGGER(ledtrig_nand);
+
+void ledtrig_mtd_activity(void)
+{
+        unsigned long blink_delay = BLINK_DELAY;
+
+        led_trigger_blink_oneshot(ledtrig_mtd,
+                                  &blink_delay, &blink_delay, 0);
+        led_trigger_blink_oneshot(ledtrig_nand,
+                                  &blink_delay, &blink_delay, 0);
+}
+EXPORT_SYMBOL(ledtrig_mtd_activity);
+
+static int __init ledtrig_mtd_init(void)
+{
+        led_trigger_register_simple("mtd", &ledtrig_mtd);
+        led_trigger_register_simple("nand-disk", &ledtrig_nand);
+
+        return 0;
+}
+device_initcall(ledtrig_mtd_init);
diff --git a/include/linux/leds.h b/include/linux/leds.h
index f203a8f89d30..19eb10278bea 100644
--- a/include/linux/leds.h
+++ b/include/linux/leds.h
@@ -329,6 +329,12 @@ extern void ledtrig_ide_activity(void);
 static inline void ledtrig_ide_activity(void) {}
 #endif
 
+#ifdef CONFIG_LEDS_TRIGGER_MTD
+extern void ledtrig_mtd_activity(void);
+#else
+static inline void ledtrig_mtd_activity(void) {}
+#endif
+
 #if defined(CONFIG_LEDS_TRIGGER_CAMERA) || defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE)
 extern void ledtrig_flash_ctrl(bool on);
 extern void ledtrig_torch_ctrl(bool on);