[PATCH v2 1/3] mmc: sdhci-omap: Fix DCRC error handling during tuning

From: Faiz Abbas
Date: Wed Nov 21 2018 - 05:31:25 EST


Commit 7d33c3581536 ("mmc: sdhci-omap: Workaround for Errata i802")
disabled DCRC interrupts during tuning. This write to the interrupt
enable register gets overwritten in sdhci_prepare_data() and the
interrupt is not in fact disabled. Fix this by disabling the interrupt
in the host->ier variable.

Fixes: 7d33c3581536 ("mmc: sdhci-omap: Workaround for Errata i802")
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Faiz Abbas <faiz_abbas@xxxxxx>
---
drivers/mmc/host/sdhci-omap.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/mmc/host/sdhci-omap.c b/drivers/mmc/host/sdhci-omap.c
index 88347ce78f23..d264391616f9 100644
--- a/drivers/mmc/host/sdhci-omap.c
+++ b/drivers/mmc/host/sdhci-omap.c
@@ -288,9 +288,9 @@ static int sdhci_omap_execute_tuning(struct mmc_host *mmc, u32 opcode)
struct device *dev = omap_host->dev;
struct mmc_ios *ios = &mmc->ios;
u32 start_window = 0, max_window = 0;
+ bool dcrc_was_enabled = false;
u8 cur_match, prev_match = 0;
u32 length = 0, max_len = 0;
- u32 ier = host->ier;
u32 phase_delay = 0;
int ret = 0;
u32 reg;
@@ -317,9 +317,10 @@ static int sdhci_omap_execute_tuning(struct mmc_host *mmc, u32 opcode)
* during the tuning procedure. So disable it during the
* tuning procedure.
*/
- ier &= ~SDHCI_INT_DATA_CRC;
- sdhci_writel(host, ier, SDHCI_INT_ENABLE);
- sdhci_writel(host, ier, SDHCI_SIGNAL_ENABLE);
+ if (host->ier & SDHCI_INT_DATA_CRC) {
+ host->ier &= ~SDHCI_INT_DATA_CRC;
+ dcrc_was_enabled = true;
+ }

while (phase_delay <= MAX_PHASE_DELAY) {
sdhci_omap_set_dll(omap_host, phase_delay);
@@ -366,6 +367,9 @@ static int sdhci_omap_execute_tuning(struct mmc_host *mmc, u32 opcode)

ret:
sdhci_reset(host, SDHCI_RESET_CMD | SDHCI_RESET_DATA);
+ /* Reenable forbidden interrupt */
+ if (dcrc_was_enabled)
+ host->ier |= SDHCI_INT_DATA_CRC;
sdhci_writel(host, host->ier, SDHCI_INT_ENABLE);
sdhci_writel(host, host->ier, SDHCI_SIGNAL_ENABLE);
return ret;
--
2.19.1