udc: Fix recursive spinlocks

Driver had recursive spinlock locking: 1. jz4740_queue() acquires lock 2. done()
is called in chain:
jz4740_queue()->jz4740_ep0_kick()->jz4740_ep0_in()->write_fifo_ep0()->done() and
it tries to acquire same lock. 3. Deadlock.

Signed-off-by:
Yauhen Kharuzhy <jekhor@gmail.com>

SVN-Revision: 21619

diff --git a/target/linux/xburst/patches-2.6.34/056-udc.patch b/target/linux/xburst/patches-2.6.34/056-udc.patch
index de84d22ca3bd3fd4e66838e3f377d94764c01b26..54978b668afea87983ee6d9ed69ac163cf2a7067 100644 (file)
--- a/target/linux/xburst/patches-2.6.34/056-udc.patch
+++ b/target/linux/xburst/patches-2.6.34/056-udc.patch
@@ -1,4 +1,4 @@
-From 9b62834f0e2aba2111ba22e734982f7c71293355 Mon Sep 17 00:00:00 2001
+From 644d56ba485f220b1b740b320760a12b5e4e0308 Mon Sep 17 00:00:00 2001
 From: Lars-Peter Clausen <lars@metafoo.de>
 Date: Sat, 24 Apr 2010 12:18:46 +0200
 Subject: [PATCH] Add jz4740 udc driver
@@ -7,9 +7,9 @@ Subject: [PATCH] Add jz4740 udc driver
  drivers/usb/gadget/Kconfig        |   14 +
  drivers/usb/gadget/Makefile       |    1 +
  drivers/usb/gadget/gadget_chips.h |    9 +
- drivers/usb/gadget/jz4740_udc.c   | 2439 +++++++++++++++++++++++++++++++++++++
- drivers/usb/gadget/jz4740_udc.h   |   99 ++
- 5 files changed, 2562 insertions(+), 0 deletions(-)
+ drivers/usb/gadget/jz4740_udc.c   | 2437 +++++++++++++++++++++++++++++++++++++
+ drivers/usb/gadget/jz4740_udc.h   |  100 ++
+ 5 files changed, 2561 insertions(+), 0 deletions(-)
  create mode 100644 drivers/usb/gadget/jz4740_udc.c
  create mode 100644 drivers/usb/gadget/jz4740_udc.h
 
@@ -84,10 +84,10 @@ index e511fec..b2ec5fb 100644
  
 diff --git a/drivers/usb/gadget/jz4740_udc.c b/drivers/usb/gadget/jz4740_udc.c
 new file mode 100644
-index 0000000..bea1a37
+index 0000000..e84c817
 --- /dev/null
 +++ b/drivers/usb/gadget/jz4740_udc.c
-@@ -0,0 +1,2439 @@
+@@ -0,0 +1,2437 @@
 +/*
 + * linux/drivers/usb/gadget/jz4740_udc.c
 + *
@@ -863,7 +863,6 @@ index 0000000..bea1a37
 +static void done(struct jz4740_ep *ep, struct jz4740_request *req, int status)
 +{
 +      unsigned int stopped = ep->stopped;
-+      unsigned long flags;
 +      uint32_t index;
 +
 +      DEBUG("%s, %p\n", __FUNCTION__, ep);
@@ -882,14 +881,14 @@ index 0000000..bea1a37
 +      /* don't modify queue heads during completion callback */
 +      ep->stopped = 1;
 +      /* Read current index (completion may modify it) */
-+      spin_lock_irqsave(&ep->dev->lock, flags);
 +      index = usb_readb(ep->dev, JZ_REG_UDC_INDEX);
++      spin_unlock_irqrestore(&ep->dev->lock, ep->dev->lock_flags);
 +
 +      req->req.complete(&ep->ep, &req->req);
 +
++      spin_lock_irqsave(&ep->dev->lock, ep->dev->lock_flags);
 +      /* Restore index */
 +      jz_udc_set_index(ep->dev, index);
-+      spin_unlock_irqrestore(&ep->dev->lock, flags);
 +      ep->stopped = stopped;
 +}
 +
@@ -1344,7 +1343,6 @@ index 0000000..bea1a37
 +      struct jz4740_request *req;
 +      struct jz4740_ep *ep;
 +      struct jz4740_udc *dev;
-+      unsigned long flags;
 +
 +      DEBUG("%s, %p\n", __FUNCTION__, _ep);
 +
@@ -1371,7 +1369,7 @@ index 0000000..bea1a37
 +      DEBUG("%s queue req %p, len %d buf %p\n", _ep->name, _req, _req->length,
 +            _req->buf);
 +
-+      spin_lock_irqsave(&dev->lock, flags);
++      spin_lock_irqsave(&dev->lock, dev->lock_flags);
 +
 +      _req->status = -EINPROGRESS;
 +      _req->actual = 0;
@@ -1417,7 +1415,7 @@ index 0000000..bea1a37
 +      if (likely(req != 0))
 +              list_add_tail(&req->queue, &ep->queue);
 +
-+      spin_unlock_irqrestore(&dev->lock, flags);
++      spin_unlock_irqrestore(&dev->lock, dev->lock_flags);
 +
 +      return 0;
 +}
@@ -2529,10 +2527,10 @@ index 0000000..bea1a37
 +MODULE_LICENSE("GPL");
 diff --git a/drivers/usb/gadget/jz4740_udc.h b/drivers/usb/gadget/jz4740_udc.h
 new file mode 100644
-index 0000000..ac1540f
+index 0000000..7156768
 --- /dev/null
 +++ b/drivers/usb/gadget/jz4740_udc.h
-@@ -0,0 +1,99 @@
+@@ -0,0 +1,100 @@
 +/*
 + * linux/drivers/usb/gadget/jz4740_udc.h
 + *
@@ -2608,6 +2606,7 @@ index 0000000..ac1540f
 +      struct usb_gadget_driver *driver;
 +      struct device *dev;
 +      spinlock_t lock;
++      unsigned long lock_flags;
 +
 +      enum ep0state ep0state;
 +      struct jz4740_ep ep[UDC_MAX_ENDPOINTS];