[PATCH 1/3] mmc: host: omap_hsmmc: Fix DTO and DCRC handling

From: Vignesh R
Date: Tue Jun 16 2015 - 06:38:27 EST


From: Kishon Vijay Abraham I <kishon@xxxxxx>

DTO/DCRC errors were not being informed to the mmc core since
commit ae4bf788ee9b ("mmc: omap_hsmmc: consolidate error report handling of
HSMMC IRQ"). This commit made sure 'end_trans' is never set on DTO/DCRC
errors. This is because after this commit 'host->data' is checked after
it has been cleared to NULL by omap_hsmmc_dma_cleanup().

Because 'end_trans' is never set, omap_hsmmc_xfer_done() is never invoked
making core layer not to be aware of DTO/DCRC errors. Because of this
any command invoked after DTO/DCRC error leads to a hang.

Fix this by checking for 'host->data' before it is actually cleared.

Fixes: ae4bf788ee9b ("mmc: omap_hsmmc: consolidate error report handling of
HSMMC IRQ")

CC: stable@xxxxxxxxxxxxxxx
Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
Signed-off-by: Vignesh R <vigneshr@xxxxxx>
---
drivers/mmc/host/omap_hsmmc.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
index 9df2b6801f76..d0abdffb0d7c 100644
--- a/drivers/mmc/host/omap_hsmmc.c
+++ b/drivers/mmc/host/omap_hsmmc.c
@@ -1062,6 +1062,10 @@ static void omap_hsmmc_do_irq(struct omap_hsmmc_host *host, int status)

if (status & (CTO_EN | CCRC_EN))
end_cmd = 1;
+ if (host->data || host->response_busy) {
+ end_trans = !end_cmd;
+ host->response_busy = 0;
+ }
if (status & (CTO_EN | DTO_EN))
hsmmc_command_incomplete(host, -ETIMEDOUT, end_cmd);
else if (status & (CCRC_EN | DCRC_EN))
@@ -1081,10 +1085,6 @@ static void omap_hsmmc_do_irq(struct omap_hsmmc_host *host, int status)
}
dev_dbg(mmc_dev(host->mmc), "AC12 err: 0x%x\n", ac12);
}
- if (host->data || host->response_busy) {
- end_trans = !end_cmd;
- host->response_busy = 0;
- }
}

OMAP_HSMMC_WRITE(host->base, STAT, status);
--
2.4.1

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