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authorRabin Vincent <rabin.vincent@axis.com>2015-11-23 08:13:45 +0100
committerMark Brown <broonie@kernel.org>2015-11-23 11:31:44 +0000
commitf3d4bb3342630cd3d89882586851498d8dc7c0f2 (patch)
treecfa8e53506ecc427d1ab043fffee145fe55c0922 /drivers/spi/spi-pl022.c
parent8005c49d9aea74d382f474ce11afbbc7d7130bec (diff)
downloadlinux-f3d4bb3342630cd3d89882586851498d8dc7c0f2.tar.bz2
spi: pl022: handle EPROBE_DEFER for dma
Handle EPROBE_DEFER explicitly so that we ensure that we get the DMA channel specified in the device tree, instead of depending on the DMA controller getting probed before us. Signed-off-by: Rabin Vincent <rabin.vincent@axis.com> Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi/spi-pl022.c')
-rw-r--r--drivers/spi/spi-pl022.c28
1 files changed, 22 insertions, 6 deletions
diff --git a/drivers/spi/spi-pl022.c b/drivers/spi/spi-pl022.c
index 94af80676684..5e5fd77e2711 100644
--- a/drivers/spi/spi-pl022.c
+++ b/drivers/spi/spi-pl022.c
@@ -1171,19 +1171,31 @@ err_no_rxchan:
static int pl022_dma_autoprobe(struct pl022 *pl022)
{
struct device *dev = &pl022->adev->dev;
+ struct dma_chan *chan;
+ int err;
/* automatically configure DMA channels from platform, normally using DT */
- pl022->dma_rx_channel = dma_request_slave_channel(dev, "rx");
- if (!pl022->dma_rx_channel)
+ chan = dma_request_slave_channel_reason(dev, "rx");
+ if (IS_ERR(chan)) {
+ err = PTR_ERR(chan);
goto err_no_rxchan;
+ }
+
+ pl022->dma_rx_channel = chan;
- pl022->dma_tx_channel = dma_request_slave_channel(dev, "tx");
- if (!pl022->dma_tx_channel)
+ chan = dma_request_slave_channel_reason(dev, "tx");
+ if (IS_ERR(chan)) {
+ err = PTR_ERR(chan);
goto err_no_txchan;
+ }
+
+ pl022->dma_tx_channel = chan;
pl022->dummypage = kmalloc(PAGE_SIZE, GFP_KERNEL);
- if (!pl022->dummypage)
+ if (!pl022->dummypage) {
+ err = -ENOMEM;
goto err_no_dummypage;
+ }
return 0;
@@ -1194,7 +1206,7 @@ err_no_txchan:
dma_release_channel(pl022->dma_rx_channel);
pl022->dma_rx_channel = NULL;
err_no_rxchan:
- return -ENODEV;
+ return err;
}
static void terminate_dma(struct pl022 *pl022)
@@ -2236,6 +2248,10 @@ static int pl022_probe(struct amba_device *adev, const struct amba_id *id)
/* Get DMA channels, try autoconfiguration first */
status = pl022_dma_autoprobe(pl022);
+ if (status == -EPROBE_DEFER) {
+ dev_dbg(dev, "deferring probe to get DMA channel\n");
+ goto err_no_irq;
+ }
/* If that failed, use channels from platform_info */
if (status == 0)