ata: ahci_platform: runtime resume the device before use

On OMAP platforms the device needs to be runtime resumed before it can
be accessed. The OMAP HWMOD framework takes care of enabling the
module and its resources based on the device's runtime PM state.

In this patch we runtime resume during .probe() and runtime suspend
after .remove().

We also update the runtime PM state during .resume().

CC: Balaji T K <balajitk@ti.com>
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

2 files changed, 16 insertions, 0 deletions

diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
index 3ab7ac9bb6a7..51af275b3388 100644
--- a/drivers/ata/ahci.h
+++ b/drivers/ata/ahci.h
@@ -324,6 +324,7 @@ struct ahci_host_priv {
         u32                     em_loc; /* enclosure management location */
         u32                     em_buf_sz;      /* EM buffer size in byte */
         u32                     em_msg_type;    /* EM message type */
+        bool                    got_runtime_pm; /* Did we do pm_runtime_get? */
         struct clk              *clks[AHCI_MAX_CLKS]; /* Optional */
         struct regulator        *target_pwr;    /* Optional */
         struct phy              *phy;           /* If platform uses phy */
diff --git a/drivers/ata/ahci_platform.c b/drivers/ata/ahci_platform.c
index 243dde36cd98..fc32863d6a5a 100644
--- a/drivers/ata/ahci_platform.c
+++ b/drivers/ata/ahci_platform.c
@@ -23,6 +23,7 @@
 #include <linux/libata.h>
 #include <linux/ahci_platform.h>
 #include <linux/phy/phy.h>
+#include <linux/pm_runtime.h>
 #include "ahci.h"
 
 static void ahci_host_stop(struct ata_host *host);
@@ -216,6 +217,11 @@ static void ahci_platform_put_resources(struct device *dev, void *res)
         struct ahci_host_priv *hpriv = res;
         int c;
 
+        if (hpriv->got_runtime_pm) {
+                pm_runtime_put_sync(dev);
+                pm_runtime_disable(dev);
+        }
+
         for (c = 0; c < AHCI_MAX_CLKS && hpriv->clks[c]; c++)
                 clk_put(hpriv->clks[c]);
 }
@@ -309,6 +315,10 @@ struct ahci_host_priv *ahci_platform_get_resources(
                 }
         }
 
+        pm_runtime_enable(dev);
+        pm_runtime_get_sync(dev);
+        hpriv->got_runtime_pm = true;
+
         devres_remove_group(dev, NULL);
         return hpriv;
 
@@ -603,6 +613,11 @@ int ahci_platform_resume(struct device *dev)
         if (rc)
                 goto disable_resources;
 
+        /* We resumed so update PM runtime state */
+        pm_runtime_disable(dev);
+        pm_runtime_set_active(dev);
+        pm_runtime_enable(dev);
+
         return 0;
 
 disable_resources: