[PATCH 4.9 139/207] dmaengine: dmaengine_desc_callback_valid(): Check for `callback_result`

From: Greg Kroah-Hartman
Date: Wed Nov 24 2021 - 07:22:10 EST


From: Lars-Peter Clausen <lars@xxxxxxxxxx>

[ Upstream commit e7e1e880b114ca640a2f280b0d5d38aed98f98c6 ]

Before the `callback_result` callback was introduced drivers coded their
invocation to the callback in a similar way to:

if (cb->callback) {
spin_unlock(&dma->lock);
cb->callback(cb->callback_param);
spin_lock(&dma->lock);
}

With the introduction of `callback_result` two helpers where introduced to
transparently handle both types of callbacks. And drivers where updated to
look like this:

if (dmaengine_desc_callback_valid(cb)) {
spin_unlock(&dma->lock);
dmaengine_desc_callback_invoke(cb, ...);
spin_lock(&dma->lock);
}

dmaengine_desc_callback_invoke() correctly handles both `callback_result`
and `callback`. But we forgot to update the dmaengine_desc_callback_valid()
function to check for `callback_result`. As a result DMA descriptors that
use the `callback_result` rather than `callback` don't have their callback
invoked by drivers that follow the pattern above.

Fix this by checking for both `callback` and `callback_result` in
dmaengine_desc_callback_valid().

Fixes: f067025bc676 ("dmaengine: add support to provide error result from a DMA transation")
Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx>
Acked-by: Dave Jiang <dave.jiang@xxxxxxxxx>
Link: https://lore.kernel.org/r/20211023134101.28042-1-lars@xxxxxxxxxx
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/dma/dmaengine.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/dma/dmaengine.h b/drivers/dma/dmaengine.h
index 882ff9448c3ba..6537b8ec03934 100644
--- a/drivers/dma/dmaengine.h
+++ b/drivers/dma/dmaengine.h
@@ -167,7 +167,7 @@ dmaengine_desc_get_callback_invoke(struct dma_async_tx_descriptor *tx,
static inline bool
dmaengine_desc_callback_valid(struct dmaengine_desc_callback *cb)
{
- return (cb->callback) ? true : false;
+ return cb->callback || cb->callback_result;
}

#endif
--
2.33.0