[PATCH 1/4] mmc: mediatek: do not tune data for HS400 mode

From: Chaotian Jing
Date: Wed Jun 29 2016 - 22:01:33 EST


for hs400 mode, should only tune DS delay, should not
tune PAD_TUNE for data path.
if eMMC will run at hs400 mode, do not tune data while
call ops->execute_tuning().

Signed-off-by: Chaotian Jing <chaotian.jing@xxxxxxxxxxxx>
---
drivers/mmc/host/mtk-sd.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
index 5642f71..4d7ce65 100644
--- a/drivers/mmc/host/mtk-sd.c
+++ b/drivers/mmc/host/mtk-sd.c
@@ -326,6 +326,7 @@ struct msdc_host {
unsigned char timing;
bool vqmmc_enabled;
u32 hs400_ds_delay;
+ bool hs400_mode; /* current eMMC will run at hs400 mode */
struct msdc_save_para save_para; /* used when gate HCLK */
};

@@ -1402,9 +1403,11 @@ static int msdc_execute_tuning(struct mmc_host *mmc, u32 opcode)
dev_err(host->dev, "Tune response fail!\n");
return ret;
}
- ret = msdc_tune_data(mmc, opcode);
- if (ret == -EIO)
- dev_err(host->dev, "Tune data fail!\n");
+ if (host->hs400_mode == false) {
+ ret = msdc_tune_data(mmc, opcode);
+ if (ret == -EIO)
+ dev_err(host->dev, "Tune data fail!\n");
+ }

return ret;
}
@@ -1412,6 +1415,7 @@ static int msdc_execute_tuning(struct mmc_host *mmc, u32 opcode)
static int msdc_prepare_hs400_tuning(struct mmc_host *mmc, struct mmc_ios *ios)
{
struct msdc_host *host = mmc_priv(mmc);
+ host->hs400_mode = true;

writel(host->hs400_ds_delay, host->base + PAD_DS_TUNE);
return 0;
--
1.8.1.1.dirty