From cc14eec0889bb06abab3d6ea1e0e0676521542c8 Mon Sep 17 00:00:00 2001 From: Yinbo Zhu Date: Fri, 23 Nov 2018 11:15:33 +0800 Subject: [PATCH] mmc: core: Add ->hs400_prepare_ddr() callback Some eMMC controllers need specific settings for HS400 mode before the speed mode can be switched to DDR mode, during the HS400 initialization sequence. For that reason, let's introduce a new host callback, ->hs400_prepare_ddr() and invoked it just before switching to DDR mode. Signed-off-by: Yinbo Zhu Signed-off-by: Ulf Hansson --- drivers/mmc/core/mmc.c | 3 +++ include/linux/mmc/host.h | 3 +++ 2 files changed, 6 insertions(+) diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index bc1bd2c..4ff08ea 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -1181,6 +1181,9 @@ static int mmc_select_hs400(struct mmc_card *card) if (err) goto out_err; + if (host->ops->hs400_prepare_ddr) + host->ops->hs400_prepare_ddr(host); + /* Switch card to DDR */ err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, EXT_CSD_BUS_WIDTH, diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index 2a5fe75..2709c94d 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -147,6 +147,9 @@ struct mmc_host_ops { /* Prepare HS400 target operating frequency depending host driver */ int (*prepare_hs400_tuning)(struct mmc_host *host, struct mmc_ios *ios); + /* Prepare switch to DDR during the HS400 init sequence */ + int (*hs400_prepare_ddr)(struct mmc_host *host); + /* Prepare for switching from HS400 to HS200 */ void (*hs400_downgrade)(struct mmc_host *host); -- 2.7.4