usb: musb: core: Convert the musb_platform_reset to have a return value.

Currently musb_platform_reset() is only used by dsps.
In case of BABBLE interrupt for other platforms the  musb_platform_reset()
is a NOP. In such situations no need to re-initialize the endpoints.
Also in the latest silicon revision of AM335x, we do have a babble recovery
mechanism without resetting the IP block. In preperation to add that support
its better to have a rest_done return for  musb_platform_reset().

Signed-off-by: George Cherian <george.cherian@ti.com>
Tested-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

3 files changed, 14 insertions, 9 deletions

diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c
index c0ce09f8fdcd..b841ee0bff06 100644
--- a/drivers/usb/musb/musb_core.c
+++ b/drivers/usb/musb/musb_core.c
@@ -1753,9 +1753,11 @@ static void musb_irq_work(struct work_struct *data)
 static void musb_recover_work(struct work_struct *data)
 {
         struct musb *musb = container_of(data, struct musb, recover_work.work);
-        int status;
+        int status, ret;
 
-        musb_platform_reset(musb);
+        ret  = musb_platform_reset(musb);
+        if (ret)
+                return;
 
         usb_phy_vbus_off(musb->xceiv);
         usleep_range(100, 200);
@@ -1764,8 +1766,8 @@ static void musb_recover_work(struct work_struct *data)
         usleep_range(100, 200);
 
         /*
-         * When a babble condition occurs, the musb controller removes the
-         * session bit and the endpoint config is lost.
+         * When a babble condition occurs, the musb controller
+         * removes the session bit and the endpoint config is lost.
          */
         if (musb->dyn_fifo)
                 status = ep_config_from_table(musb);
diff --git a/drivers/usb/musb/musb_core.h b/drivers/usb/musb/musb_core.h
index 9241025f6965..414e57a984bb 100644
--- a/drivers/usb/musb/musb_core.h
+++ b/drivers/usb/musb/musb_core.h
@@ -192,7 +192,7 @@ struct musb_platform_ops {
 
         int     (*set_mode)(struct musb *musb, u8 mode);
         void    (*try_idle)(struct musb *musb, unsigned long timeout);
-        void    (*reset)(struct musb *musb);
+        int     (*reset)(struct musb *musb);
 
         int     (*vbus_status)(struct musb *musb);
         void    (*set_vbus)(struct musb *musb, int on);
@@ -555,10 +555,12 @@ static inline void musb_platform_try_idle(struct musb *musb,
                 musb->ops->try_idle(musb, timeout);
 }
 
-static inline void musb_platform_reset(struct musb *musb)
+static inline int  musb_platform_reset(struct musb *musb)
 {
-        if (musb->ops->reset)
-                musb->ops->reset(musb);
+        if (!musb->ops->reset)
+                return -EINVAL;
+
+        return musb->ops->reset(musb);
 }
 
 static inline int musb_platform_get_vbus_status(struct musb *musb)
diff --git a/drivers/usb/musb/musb_dsps.c b/drivers/usb/musb/musb_dsps.c
index b29f59f718bb..53a4351aef97 100644
--- a/drivers/usb/musb/musb_dsps.c
+++ b/drivers/usb/musb/musb_dsps.c
@@ -544,7 +544,7 @@ static int dsps_musb_set_mode(struct musb *musb, u8 mode)
         return 0;
 }
 
-static void dsps_musb_reset(struct musb *musb)
+static int dsps_musb_reset(struct musb *musb)
 {
         struct device *dev = musb->controller;
         struct dsps_glue *glue = dev_get_drvdata(dev->parent);
@@ -556,6 +556,7 @@ static void dsps_musb_reset(struct musb *musb)
         usleep_range(100, 200);
         usb_phy_init(musb->xceiv);
 
+        return 0;
 }
 
 static struct musb_platform_ops dsps_ops = {