From e683b423007b9befec30c672c695d0e6abf87493 Mon Sep 17 00:00:00 2001 From: Haavard Skinnemoen Date: Mon, 6 Oct 2008 20:09:53 +0200 Subject: atmel-mci: Initialize BLKR before sending data transfer command The atmel-mci driver sometimes fails data transfers like this: mmcblk0: error -5 transferring data end_request: I/O error, dev mmcblk0, sector 2749769 end_request: I/O error, dev mmcblk0, sector 2749777 It turns out that this might be caused by the BLKR register (which contains the block size and the number of blocks being transfered) being initialized too late. This patch moves the initialization of BLKR so that it contains the correct value before the block transfer command is sent. This error is difficult to reproduce, but if you insert a long delay (mdelay(10) or thereabouts) between the calls to atmci_start_command() and atmci_submit_data(), all transfers seem to fail without this patch, while I haven't seen any failures with this patch. Reported-by: Hein_Tibosch Signed-off-by: Haavard Skinnemoen Signed-off-by: Pierre Ossman Signed-off-by: Linus Torvalds --- drivers/mmc/host/atmel-mci.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'drivers/mmc') diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c index 917035e16da4..00008967ef7a 100644 --- a/drivers/mmc/host/atmel-mci.c +++ b/drivers/mmc/host/atmel-mci.c @@ -426,8 +426,6 @@ static u32 atmci_submit_data(struct mmc_host *mmc, struct mmc_data *data) host->sg = NULL; host->data = data; - mci_writel(host, BLKR, MCI_BCNT(data->blocks) - | MCI_BLKLEN(data->blksz)); dev_vdbg(&mmc->class_dev, "BLKR=0x%08x\n", MCI_BCNT(data->blocks) | MCI_BLKLEN(data->blksz)); @@ -483,6 +481,10 @@ static void atmci_request(struct mmc_host *mmc, struct mmc_request *mrq) if (data->blocks > 1 && data->blksz & 3) goto fail; atmci_set_timeout(host, data); + + /* Must set block count/size before sending command */ + mci_writel(host, BLKR, MCI_BCNT(data->blocks) + | MCI_BLKLEN(data->blksz)); } iflags = MCI_CMDRDY; -- cgit v1.2.1