From b33d46c398fd071dccd0815f33620924684860cd Mon Sep 17 00:00:00 2001 From: Ulf Hansson Date: Sat, 5 Mar 2011 14:36:24 +0100 Subject: [PATCH] mmc: core: reset card voltage after power off At power off, reset OCR mask to be the highest possible voltage supported for the current mmc host. This solves the re-initialization during the power up sequence. The voltage may have been decreased due to the card accepts a lower voltage than the voltage used during the initialization sequence. We need to reset the voltage to by the host highest possible value since according to specification the initialization must always be done at high voltage. Reviewed-by: Jonas Aberg Signed-off-by: Ulf Hansson Signed-off-by: Linus Walleij Signed-off-by: Chris Ball --- drivers/mmc/core/core.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index 4956da1..1f453ac 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -1009,6 +1009,13 @@ static void mmc_power_off(struct mmc_host *host) { host->ios.clock = 0; host->ios.vdd = 0; + + /* + * Reset ocr mask to be the highest possible voltage supported for + * this mmc host. This value will be used at next power up. + */ + host->ocr = 1 << (fls(host->ocr_avail) - 1); + if (!mmc_host_is_spi(host)) { host->ios.bus_mode = MMC_BUSMODE_OPENDRAIN; host->ios.chip_select = MMC_CS_DONTCARE; -- 2.7.4