[PATCH] mmc: core: need retune if error value is -EIO

From: Shawn Lin
Date: Thu Aug 04 2016 - 04:37:10 EST


We need to do retune if receiving -EIO, otherwise we
could see debug dump like:

[ 89.057226] bcmsdh_sdmmc: Failed to Read byte F1:@0x1001f=ff, Err: -5
[ 89.058811] bcmsdh_sdmmc: Failed to Read byte F1:@0x1001f=ff, Err: -5
[ 89.059415] bcmsdh_sdmmc: Failed to Read byte F1:@0x1000e=ff, Err: -84
[ 89.254248] dwmmc_rockchip fe310000.dwmmc: Successfully tuned phase to 199
[ 89.273912] dhd_set_suspend: Remove extra suspend setting
[ 89.274478] dhd_enable_packet_filter: enter, value = 0
64 bytes from 112.90.83.112: icmp_seq=24 ttl=53 time=1321 ms
64 bytes from 112.90.83.112: icmp_seq=25 ttl=53 time=319 ms
64 bytes from 112.90.83.112: icmp_seq=26 ttl=53 time=69.8 ms
64 bytes from 112.90.83.112: icmp_seq=27 ttl=53 time=37.5 ms
...

In this case we see dw_mmc finally enter retune process, but
if this patch is applied, we could save more time to make it
work. Also many host drivers will generate -EIO, so this patch
can also prevent them from failing to enter retune process.

Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
---

drivers/mmc/core/core.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index e55cde6..18d0af5 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -133,7 +133,8 @@ void mmc_request_done(struct mmc_host *host, struct mmc_request *mrq)
/* Flag re-tuning needed on CRC errors */
if ((cmd->opcode != MMC_SEND_TUNING_BLOCK &&
cmd->opcode != MMC_SEND_TUNING_BLOCK_HS200) &&
- (err == -EILSEQ || (mrq->sbc && mrq->sbc->error == -EILSEQ) ||
+ (err == -EILSEQ || err == -EIO ||
+ (mrq->sbc && mrq->sbc->error == -EILSEQ) ||
(mrq->data && mrq->data->error == -EILSEQ) ||
(mrq->stop && mrq->stop->error == -EILSEQ)))
mmc_retune_needed(host);
--
2.3.7