mfd: omap-usb-tll: Don't hold lock during pm_runtime_get/put_sync()

pm_runtime_get/put_sync() can sleep so don't hold spinlock while
calling them.

This patch prevents a BUG() during system suspend when
CONFIG_DEBUG_ATOMIC_SLEEP is enabled.

Bug is present in Kernel versions v3.9 onwards.

Reported-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Roger Quadros <rogerq@ti.com>
Tested-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

1 files changed, 12 insertions, 24 deletions

diff --git a/drivers/mfd/omap-usb-tll.c b/drivers/mfd/omap-usb-tll.c
index ee7468c1cb60..5ee50f779ef6 100644
--- a/drivers/mfd/omap-usb-tll.c
+++ b/drivers/mfd/omap-usb-tll.c
@@ -333,21 +333,17 @@ int omap_tll_init(struct usbhs_omap_platform_data *pdata)
         unsigned reg;
         struct usbtll_omap *tll;
 
-        spin_lock(&tll_lock);
-
-        if (!tll_dev) {
-                spin_unlock(&tll_lock);
+        if (!tll_dev)
                 return -ENODEV;
-        }
 
-        tll = dev_get_drvdata(tll_dev);
+        pm_runtime_get_sync(tll_dev);
 
+        spin_lock(&tll_lock);
+        tll = dev_get_drvdata(tll_dev);
         needs_tll = false;
         for (i = 0; i < tll->nch; i++)
                 needs_tll |= omap_usb_mode_needs_tll(pdata->port_mode[i]);
 
-        pm_runtime_get_sync(tll_dev);
-
         if (needs_tll) {
                 void __iomem *base = tll->base;
 
@@ -398,9 +394,8 @@ int omap_tll_init(struct usbhs_omap_platform_data *pdata)
                 }
         }
 
-        pm_runtime_put_sync(tll_dev);
-
         spin_unlock(&tll_lock);
+        pm_runtime_put_sync(tll_dev);
 
         return 0;
 }
@@ -411,17 +406,14 @@ int omap_tll_enable(struct usbhs_omap_platform_data *pdata)
         int i;
         struct usbtll_omap *tll;
 
-        spin_lock(&tll_lock);
-
-        if (!tll_dev) {
-                spin_unlock(&tll_lock);
+        if (!tll_dev)
                 return -ENODEV;
-        }
-
-        tll = dev_get_drvdata(tll_dev);
 
         pm_runtime_get_sync(tll_dev);
 
+        spin_lock(&tll_lock);
+        tll = dev_get_drvdata(tll_dev);
+
         for (i = 0; i < tll->nch; i++) {
                 if (omap_usb_mode_needs_tll(pdata->port_mode[i])) {
                         int r;
@@ -448,13 +440,10 @@ int omap_tll_disable(struct usbhs_omap_platform_data *pdata)
         int i;
         struct usbtll_omap *tll;
 
-        spin_lock(&tll_lock);
-
-        if (!tll_dev) {
-                spin_unlock(&tll_lock);
+        if (!tll_dev)
                 return -ENODEV;
-        }
 
+        spin_lock(&tll_lock);
         tll = dev_get_drvdata(tll_dev);
 
         for (i = 0; i < tll->nch; i++) {
@@ -464,9 +453,8 @@ int omap_tll_disable(struct usbhs_omap_platform_data *pdata)
                 }
         }
 
-        pm_runtime_put_sync(tll_dev);
-
         spin_unlock(&tll_lock);
+        pm_runtime_put_sync(tll_dev);
 
         return 0;
 }