From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Lars-Peter Clausen <lars@metafoo.de>,
        Dave Jiang <dave.jiang@intel.com>,
        Vinod Koul <vkoul@kernel.org>, Sasha Levin <sashal@kernel.org>
Subject: [PATCH 5.4 306/355] dmaengine: dmaengine_desc_callback_valid(): Check for `callback_result`
Date:   Mon, 15 Nov 2021 18:03:50 +0100
Message-Id: <20211115165323.622129236@linuxfoundation.org>
In-Reply-To: <20211115165313.549179499@linuxfoundation.org>
References: <20211115165313.549179499@linuxfoundation.org>
User-Agent: quilt/0.66
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Lars-Peter Clausen <lars@metafoo.de>

[ 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@metafoo.de>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20211023134101.28042-1-lars@metafoo.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 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 501c0b063f852..302f13efd35d9 100644
--- a/drivers/dma/dmaengine.h
+++ b/drivers/dma/dmaengine.h
@@ -168,7 +168,7 @@ 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