[PATCH 4.2 003/110] mmc: core: Fix init_card in 52Mhz

From: Greg Kroah-Hartman
Date: Fri Nov 06 2015 - 14:22:21 EST


4.2-stable review patch. If anyone has any objections, please let me know.

------------------

From: Chaotian Jing <chaotian.jing@xxxxxxxxxxxx>

commit 08b137d90eec51b0e90c42e123ca8ceb118d233f upstream.

Suppose that we got a data crc error, and it triggers the mmc_reset.
mmc_reset will call mmc_send_status to see if HW reset was supported.
before issue CMD13, it will do retune, and if EMMC was in HS400 mode,
it will reduce frequency to 52Mhz firstly, then results in card init
was doing at 52Mhz.
The mmc_send_status was originally only done for mmc_test, should drop
it. And, rename the "eMMC hardware reset" to "Reset test", as we would
also be able to use the test for SD-cards.

Signed-off-by: Chaotian Jing <chaotian.jing@xxxxxxxxxxxx>
Suggested-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Fixes: bd11e8bd03ca ("mmc: core: Flag re-tuning is needed on CRC errors")
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/mmc/card/mmc_test.c | 9 +++------
drivers/mmc/core/mmc.c | 7 -------
2 files changed, 3 insertions(+), 13 deletions(-)

--- a/drivers/mmc/card/mmc_test.c
+++ b/drivers/mmc/card/mmc_test.c
@@ -2263,15 +2263,12 @@ static int mmc_test_profile_sglen_r_nonb
/*
* eMMC hardware reset.
*/
-static int mmc_test_hw_reset(struct mmc_test_card *test)
+static int mmc_test_reset(struct mmc_test_card *test)
{
struct mmc_card *card = test->card;
struct mmc_host *host = card->host;
int err;

- if (!mmc_card_mmc(card) || !mmc_can_reset(card))
- return RESULT_UNSUP_CARD;
-
err = mmc_hw_reset(host);
if (!err)
return RESULT_OK;
@@ -2605,8 +2602,8 @@ static const struct mmc_test_case mmc_te
},

{
- .name = "eMMC hardware reset",
- .run = mmc_test_hw_reset,
+ .name = "Reset test",
+ .run = mmc_test_reset,
},
};

--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -1924,7 +1924,6 @@ EXPORT_SYMBOL(mmc_can_reset);
static int mmc_reset(struct mmc_host *host)
{
struct mmc_card *card = host->card;
- u32 status;

if (!(host->caps & MMC_CAP_HW_RESET) || !host->ops->hw_reset)
return -EOPNOTSUPP;
@@ -1937,12 +1936,6 @@ static int mmc_reset(struct mmc_host *ho

host->ops->hw_reset(host);

- /* If the reset has happened, then a status command will fail */
- if (!mmc_send_status(card, &status)) {
- mmc_host_clk_release(host);
- return -ENOSYS;
- }
-
/* Set initial state and call mmc_set_ios */
mmc_set_initial_state(host);
mmc_host_clk_release(host);


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