From 467e081d23e67f6216cbe0df911bd5017f1f0b55 Mon Sep 17 00:00:00 2001 From: "ludovic.desroches@atmel.com" Date: Mon, 1 Dec 2014 15:35:09 +0100 Subject: [PATCH] mmc: atmel-mci: use probe deferring if dma controller is not ready yet Return probe defer if requesting a dma channel without a dma controller probed. Signed-off-by: Ludovic Desroches Signed-off-by: Ulf Hansson --- drivers/mmc/host/atmel-mci.c | 48 ++++++++++++++++++++++---------------------- 1 file changed, 24 insertions(+), 24 deletions(-) diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c index 00f6088..62aba9a 100644 --- a/drivers/mmc/host/atmel-mci.c +++ b/drivers/mmc/host/atmel-mci.c @@ -2272,29 +2272,25 @@ static void atmci_cleanup_slot(struct atmel_mci_slot *slot, mmc_free_host(slot->mmc); } -static bool atmci_configure_dma(struct atmel_mci *host) +static int atmci_configure_dma(struct atmel_mci *host) { - if (host == NULL) - return false; + host->dma.chan = dma_request_slave_channel_reason(&host->pdev->dev, + "rxtx"); + if (IS_ERR(host->dma.chan)) + return PTR_ERR(host->dma.chan); + + dev_info(&host->pdev->dev, "using %s for DMA transfers\n", + dma_chan_name(host->dma.chan)); + + host->dma_conf.src_addr = host->mapbase + ATMCI_RDR; + host->dma_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + host->dma_conf.src_maxburst = 1; + host->dma_conf.dst_addr = host->mapbase + ATMCI_TDR; + host->dma_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + host->dma_conf.dst_maxburst = 1; + host->dma_conf.device_fc = false; - host->dma.chan = dma_request_slave_channel(&host->pdev->dev, "rxtx"); - 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)); - - host->dma_conf.src_addr = host->mapbase + ATMCI_RDR; - host->dma_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; - host->dma_conf.src_maxburst = 1; - host->dma_conf.dst_addr = host->mapbase + ATMCI_TDR; - host->dma_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; - host->dma_conf.dst_maxburst = 1; - host->dma_conf.device_fc = false; - return true; - } + return 0; } /* @@ -2411,7 +2407,10 @@ static int atmci_probe(struct platform_device *pdev) /* Get MCI capabilities and set operations according to it */ atmci_get_cap(host); - if (atmci_configure_dma(host)) { + ret = atmci_configure_dma(host); + if (ret == -EPROBE_DEFER) + goto err_dma_probe_defer; + if (ret == 0) { host->prepare_data = &atmci_prepare_data_dma; host->submit_data = &atmci_submit_data_dma; host->stop_transfer = &atmci_stop_transfer_dma; @@ -2496,8 +2495,9 @@ err_init_slot: pm_runtime_put_noidle(&pdev->dev); del_timer_sync(&host->timer); - if (host->dma.chan) + if (!IS_ERR(host->dma.chan)) dma_release_channel(host->dma.chan); +err_dma_probe_defer: free_irq(irq, host); return ret; } @@ -2523,7 +2523,7 @@ static int atmci_remove(struct platform_device *pdev) atmci_readl(host, ATMCI_SR); del_timer_sync(&host->timer); - if (host->dma.chan) + if (!IS_ERR(host->dma.chan)) dma_release_channel(host->dma.chan); free_irq(platform_get_irq(pdev, 0), host); -- 2.7.4