From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefan Roese Subject: [PATCH] mmc: omap_hsmmc: Add small delay after enabling power Date: Thu, 11 Sep 2014 16:11:05 +0200 Message-ID: <1410444665-24492-1-git-send-email-sr@denx.de> Return-path: Sender: linux-omap-owner@vger.kernel.org To: linux-mmc@vger.kernel.org Cc: linux-omap@vger.kernel.org, Thorsten Einsbein , Ulf Hansson , Balaji T K List-Id: linux-mmc@vger.kernel.org From: Thorsten Einsbein On the TAO3530 (OMAP3530 based) we noticed that some SD cards are not detected reliably upon bootup (timeout). Especially the SanDisk Ultra 8GiB seems to be problematic here. The SanDisk Extreme also has this problem on this platform, but not that often. A Samsung 8 GiB type 6 doesn't show this problem at all. This patch now adds a short delay after enabling the power on the slot. With this delay all cards are detected reliably. Signed-off-by: Thorsten Einsbein Signed-off-by: Stefan Roese Cc: Ulf Hansson Cc: Balaji T K --- drivers/mmc/host/omap_hsmmc.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c index 9656726..62ff0a7 100644 --- a/drivers/mmc/host/omap_hsmmc.c +++ b/drivers/mmc/host/omap_hsmmc.c @@ -335,6 +335,10 @@ static int omap_hsmmc_set_power(struct device *dev, int slot, int power_on, ret = mmc_regulator_set_ocr(host->mmc, host->vcc, 0); } + + dev_dbg(host->dev, "omap_hsmmc_set_power: wait a little (slot %d)\n", + slot); + msleep(5); } else { /* Shut down the rail */ if (host->vcc_aux) -- 2.1.0