This patch improves low speeds for SD cards. OMAP-MMC controller's can support maximum bus width of '8'. when bus width is mentioned as "8" in controller data,the SD stack will check whether bus width is "4" and if not it will set bus width to "1" and there by degrading peformance. This patch fixes the issue and improves the performance of SD cards. Signed-off-by: Kishore Kadiyala <kishore.kadiyala@xxxxxx> --- Here are my experiment numbers, on a Class 6 SDHC card: Read peformance is increased by 220% Write Performance is increased by 52% drivers/mmc/host/omap_hsmmc.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c index 83f0aff..8c97c22 100644 --- a/drivers/mmc/host/omap_hsmmc.c +++ b/drivers/mmc/host/omap_hsmmc.c @@ -2092,7 +2092,7 @@ static int __init omap_hsmmc_probe(struct platform_device *pdev) MMC_CAP_WAIT_WHILE_BUSY; if (mmc_slot(host).wires >= 8) - mmc->caps |= MMC_CAP_8_BIT_DATA; + mmc->caps |= (MMC_CAP_8_BIT_DATA | MMC_CAP_4_BIT_DATA); else if (mmc_slot(host).wires >= 4) mmc->caps |= MMC_CAP_4_BIT_DATA; -- 1.6.3.3
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