[PATCH 1/2] mmc: atmel-mci: don't use dma features when dma is present but there is no chan available
From: ludovic.desroches at atmel.com <hidden>
Date: 2012-02-09 15:33:53
Also in:
linux-mmc
Subsystem:
microchip mmc/sd/sdio mci driver, multimedia card (mmc), secure digital (sd) and sdio subsystem, the rest · Maintainers:
Aubin Constans, Ulf Hansson, Linus Torvalds
From: Ludovic Desroches <redacted> 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 <redacted> Signed-off-by: Nicolas Ferre <redacted> --- 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