[PATCH v2] b44: fix resume, request_irq after hw reset

From: James Hogan
Date: Sun Oct 17 2010 - 07:49:39 EST


On resume, call request_irq() after resetting the hardware rather than
before. It's a shared interrupt so the handler could be called
immediately if another device on the same irq interrupts (and will be
called immediately if CONFIG_DEBUG_SHIRQ=y), but unless the hardware is
reinitialised with b44_init_hw() the read of the interrupt status
register will hang the system.

Signed-off-by: James Hogan <james@xxxxxxxxxxxxx>
---
drivers/net/b44.c | 19 ++++++++++++++-----
1 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/drivers/net/b44.c b/drivers/net/b44.c
index efeffdf..f950505 100644
--- a/drivers/net/b44.c
+++ b/drivers/net/b44.c
@@ -2296,18 +2296,27 @@ static int b44_resume(struct ssb_device *sdev)
if (!netif_running(dev))
return 0;

+ spin_lock_irq(&bp->lock);
+ b44_init_rings(bp);
+ b44_init_hw(bp, B44_FULL_RESET);
+ spin_unlock_irq(&bp->lock);
+
+ /*
+ * As a shared interrupt, the handler can be called immediately. To be
+ * able to check the interrupt status the hardware must already be
+ * powered back on (b44_init_hw).
+ */
rc = request_irq(dev->irq, b44_interrupt, IRQF_SHARED, dev->name, dev);
if (rc) {
netdev_err(dev, "request_irq failed\n");
+ spin_lock_irq(&bp->lock);
+ b44_halt(bp);
+ b44_free_rings(bp);
+ spin_unlock_irq(&bp->lock);
return rc;
}

- spin_lock_irq(&bp->lock);
-
- b44_init_rings(bp);
- b44_init_hw(bp, B44_FULL_RESET);
netif_device_attach(bp->dev);
- spin_unlock_irq(&bp->lock);

b44_enable_ints(bp);
netif_wake_queue(dev);
--
1.7.2.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/