mmc: add led trigger

Add a led trigger for each host controller that indicates if there
is a request active on the controller.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>

3 files changed, 16 insertions, 0 deletions

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index bad39442f8fe..09435e0ec680 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -18,6 +18,7 @@
 #include <linux/delay.h>
 #include <linux/pagemap.h>
 #include <linux/err.h>
+#include <linux/leds.h>
 #include <asm/scatterlist.h>
 #include <linux/scatterlist.h>
 
@@ -92,6 +93,8 @@ void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
                 cmd->error = 0;
                 host->ops->request(host, mrq);
         } else {
+                led_trigger_event(host->led, LED_OFF);
+
                 pr_debug("%s: req done (CMD%u): %d: %08x %08x %08x %08x\n",
                         mmc_hostname(host), cmd->opcode, err,
                         cmd->resp[0], cmd->resp[1],
@@ -146,6 +149,8 @@ mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
 
         WARN_ON(!host->claimed);
 
+        led_trigger_event(host->led, LED_FULL);
+
         mrq->cmd->error = 0;
         mrq->cmd->mrq = mrq;
         if (mrq->data) {
diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c
index 37b761891d67..64fbc9759a30 100644
--- a/drivers/mmc/core/host.c
+++ b/drivers/mmc/core/host.c
@@ -15,6 +15,7 @@
 #include <linux/err.h>
 #include <linux/idr.h>
 #include <linux/pagemap.h>
+#include <linux/leds.h>
 
 #include <linux/mmc/host.h>
 
@@ -115,6 +116,8 @@ int mmc_add_host(struct mmc_host *host)
         snprintf(host->class_dev.bus_id, BUS_ID_SIZE,
                  "mmc%d", host->index);
 
+        led_trigger_register_simple(host->class_dev.bus_id, &host->led);
+
         err = device_add(&host->class_dev);
         if (err)
                 return err;
@@ -140,6 +143,8 @@ void mmc_remove_host(struct mmc_host *host)
 
         device_del(&host->class_dev);
 
+        led_trigger_unregister(host->led);
+
         spin_lock(&mmc_host_lock);
         idr_remove(&mmc_host_idr, host->index);
         spin_unlock(&mmc_host_lock);
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 76eef94782f8..125eee1407ff 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -10,6 +10,8 @@
 #ifndef LINUX_MMC_HOST_H
 #define LINUX_MMC_HOST_H
 
+#include <linux/leds.h>
+
 #include <linux/mmc/core.h>
 
 struct mmc_ios {
@@ -133,6 +135,10 @@ struct mmc_host {
         struct task_struct      *sdio_irq_thread;
         atomic_t                sdio_irq_thread_abort;
 
+#ifdef CONFIG_LEDS_TRIGGERS
+        struct led_trigger      *led;           /* activity led */
+#endif
+
         unsigned long           private[0] ____cacheline_aligned;
 };