From 6f8f20f85deeed9be351f8da36f2b38136207063 Mon Sep 17 00:00:00 2001 From: Marek Vasut <marek.vasut+renesas@gmail.com> Date: Wed, 13 Jun 2018 08:02:55 +0200 Subject: [PATCH] mmc: tmio: Do not set divider to 1 in DDR mode The TMIO core has a quirk where divider == 1 must not be set in DDR modes. Handle this by setting divider to 2, as suggested in the documentation. Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> --- drivers/mmc/tmio-common.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/mmc/tmio-common.c b/drivers/mmc/tmio-common.c index 3ba2f07460..424b60ce52 100644 --- a/drivers/mmc/tmio-common.c +++ b/drivers/mmc/tmio-common.c @@ -574,6 +574,10 @@ static void tmio_sd_set_clk_rate(struct tmio_sd_priv *priv, divisor = DIV_ROUND_UP(mclk, mmc->clock); + /* Do not set divider to 0xff in DDR mode */ + if (mmc->ddr_mode && (divisor == 1)) + divisor = 2; + if (divisor <= 1) val = (priv->caps & TMIO_SD_CAP_RCAR) ? TMIO_SD_CLKCTL_RCAR_DIV1 : TMIO_SD_CLKCTL_DIV1; -- 2.39.5