diff options
| author | Peter Ujfalusi <peter.ujfalusi@gmail.com> | 2021-07-17 22:00:21 +0300 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2021-07-28 10:24:50 +0300 |
| commit | eda97cb095f2958bbad55684a6ca3e7d7af0176a (patch) | |
| tree | 07fc1139c303fe587cd544473474238ee591a503 /drivers/dma/of-dma.c | |
| parent | baa16371c9525f24d508508e4d296c031e1de29c (diff) | |
| download | linux-eda97cb095f2958bbad55684a6ca3e7d7af0176a.tar.xz | |
dmaengine: of-dma: router_xlate to return -EPROBE_DEFER if controller is not yet available
If the router_xlate can not find the controller in the available DMA
devices then it should return with -EPORBE_DEFER in a same way as the
of_dma_request_slave_channel() does.
The issue can be reproduced if the event router is registered before the
DMA controller itself and a driver would request for a channel before the
controller is registered.
In of_dma_request_slave_channel():
1. of_dma_find_controller() would find the dma_router
2. ofdma->of_dma_xlate() would fail and returned NULL
3. -ENODEV is returned as error code
with this patch we would return in this case the correct -EPROBE_DEFER and
the client can try to request the channel later.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Link: https://lore.kernel.org/r/20210717190021.21897-1-peter.ujfalusi@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/dma/of-dma.c')
| -rw-r--r-- | drivers/dma/of-dma.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/drivers/dma/of-dma.c b/drivers/dma/of-dma.c index ec00b20ae8e4..ac61ecda2926 100644 --- a/drivers/dma/of-dma.c +++ b/drivers/dma/of-dma.c @@ -67,8 +67,12 @@ static struct dma_chan *of_dma_router_xlate(struct of_phandle_args *dma_spec, return NULL; ofdma_target = of_dma_find_controller(&dma_spec_target); - if (!ofdma_target) - return NULL; + if (!ofdma_target) { + ofdma->dma_router->route_free(ofdma->dma_router->dev, + route_data); + chan = ERR_PTR(-EPROBE_DEFER); + goto err; + } chan = ofdma_target->of_dma_xlate(&dma_spec_target, ofdma_target); if (IS_ERR_OR_NULL(chan)) { @@ -89,6 +93,7 @@ static struct dma_chan *of_dma_router_xlate(struct of_phandle_args *dma_spec, } } +err: /* * Need to put the node back since the ofdma->of_dma_route_allocate * has taken it for generating the new, translated dma_spec |