From: Peter Ujfalusi <peter.ujfalusi@ti.com>
To: vkoul@kernel.org, dan.j.williams@intel.com
Cc: dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: dmaengine: dma_request_chan_by_mask() to handle deferred probing
Date: Wed, 18 Jul 2018 12:29:57 +0300 [thread overview]
Message-ID: <20180718092957.1934-1-peter.ujfalusi@ti.com> (raw)
If there are no DMA devices registered yet, return with EPROBE_DEFER
similarly to the case when requesting a slave channel.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
---
drivers/dma/dmaengine.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index d8fc7b58e506..f62e59e1a264 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -768,8 +768,14 @@ struct dma_chan *dma_request_chan_by_mask(const dma_cap_mask_t *mask)
return ERR_PTR(-ENODEV);
chan = __dma_request_channel(mask, NULL, NULL);
- if (!chan)
- chan = ERR_PTR(-ENODEV);
+ if (!chan) {
+ mutex_lock(&dma_list_mutex);
+ if (list_empty(&dma_device_list))
+ chan = ERR_PTR(-EPROBE_DEFER);
+ else
+ chan = ERR_PTR(-ENODEV);
+ mutex_unlock(&dma_list_mutex);
+ }
return chan;
}
next reply other threads:[~2018-07-18 9:29 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-07-18 9:29 Peter Ujfalusi [this message]
-- strict thread matches above, loose matches on Subject: below --
2018-07-25 12:34 dmaengine: dma_request_chan_by_mask() to handle deferred probing Vinod Koul
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