[PATCH 1/2] mmc: atmel-mci: don't use dma features when dma is present but there is no chan available
ludovic.desroches at atmel.com
ludovic.desroches at atmel.com
Thu Feb 9 10:33:53 EST 2012
From: Ludovic Desroches <ludovic.desroches at atmel.com>
Some callbacks are set too early ie we can have dma capabilities but we can't
get a dma channel. So wait to get the dma channel before setting callbacks
and change logs consequently.
Signed-off-by: Ludovic Desroches <ludovic.desroches at atmel.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre at atmel.com>
---
drivers/mmc/host/atmel-mci.c | 21 ++++++++++-----------
1 files changed, 10 insertions(+), 11 deletions(-)
diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
index a7ee502..e71a158 100644
--- a/drivers/mmc/host/atmel-mci.c
+++ b/drivers/mmc/host/atmel-mci.c
@@ -1941,12 +1941,12 @@ static bool atmci_filter(struct dma_chan *chan, void *slave)
}
}
-static void atmci_configure_dma(struct atmel_mci *host)
+static bool atmci_configure_dma(struct atmel_mci *host)
{
struct mci_platform_data *pdata;
if (host == NULL)
- return;
+ return false;
pdata = host->pdev->dev.platform_data;
@@ -1963,12 +1963,15 @@ static void atmci_configure_dma(struct atmel_mci *host)
host->dma.chan =
dma_request_channel(mask, atmci_filter, pdata->dma_slave);
}
- if (!host->dma.chan)
- dev_notice(&host->pdev->dev, "DMA not available, using PIO\n");
- else
+ if (!host->dma.chan) {
+ dev_warn(&host->pdev->dev, "no DMA channel available\n");
+ return false;
+ } else {
dev_info(&host->pdev->dev,
"Using %s for DMA transfers\n",
dma_chan_name(host->dma.chan));
+ return true;
+ }
}
static inline unsigned int atmci_get_version(struct atmel_mci *host)
@@ -2078,8 +2081,7 @@ static int __init atmci_probe(struct platform_device *pdev)
/* Get MCI capabilities and set operations according to it */
atmci_get_cap(host);
- if (host->caps.has_dma) {
- dev_info(&pdev->dev, "using DMA\n");
+ if (host->caps.has_dma && atmci_configure_dma(host)) {
host->prepare_data = &atmci_prepare_data_dma;
host->submit_data = &atmci_submit_data_dma;
host->stop_transfer = &atmci_stop_transfer_dma;
@@ -2089,15 +2091,12 @@ static int __init atmci_probe(struct platform_device *pdev)
host->submit_data = &atmci_submit_data_pdc;
host->stop_transfer = &atmci_stop_transfer_pdc;
} else {
- dev_info(&pdev->dev, "no DMA, no PDC\n");
+ dev_info(&pdev->dev, "using PIO\n");
host->prepare_data = &atmci_prepare_data;
host->submit_data = &atmci_submit_data;
host->stop_transfer = &atmci_stop_transfer;
}
- if (host->caps.has_dma)
- atmci_configure_dma(host);
-
platform_set_drvdata(pdev, host);
/* We need at least one slot to succeed */
--
1.7.5.4
More information about the linux-arm-kernel
mailing list