This patch adds a check for the presence of the channel controller when
trying to allocate a slot.  Without this fix, the kernel panics with a NULL
pointer dereference when the dma-engine drivers are probed.

Signed-off-by: Cyril Chemparathy <[email protected]>
---
 arch/arm/mach-davinci/dma.c |    3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/arm/mach-davinci/dma.c b/arch/arm/mach-davinci/dma.c
index a685e97..2fee31e 100644
--- a/arch/arm/mach-davinci/dma.c
+++ b/arch/arm/mach-davinci/dma.c
@@ -743,6 +743,9 @@ EXPORT_SYMBOL(edma_free_channel);
  */
 int edma_alloc_slot(unsigned ctlr, int slot)
 {
+       if (!edma_cc[ctlr])
+               return -ENODEV;
+
        if (slot >= 0)
                slot = EDMA_CHAN_SLOT(slot);
 
-- 
1.7.9.5

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

Reply via email to