atmel-mci: Don't overwrite error bits when NOTBUSY is set

After a data error, we wait for the NOTBUSY bit to be set so that we can
be sure the data transfer is completely finished. However, when NOTBUSY
is set, the interrupt handler copies the contents of SR into
data_status, overwriting any error bits we may have detected earlier.

To avoid this, initialize data_status to 0 before starting a request, and
don't overwrite it unless it still contains 0.

Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>

diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
index d45dfa259386fc934d1bdcc5294a875c69f76465..02529af7c7476f80f2df55721c4102cb2637a42f 100644 (file)
--- a/drivers/mmc/host/atmel-mci.c
+++ b/drivers/mmc/host/atmel-mci.c
@@ -694,6 +694,7 @@ static void atmci_start_request(struct atmel_mci *host,
 
        host->pending_events = 0;
        host->completed_events = 0;
+       host->data_status = 0;
 
        if (host->need_reset) {
                mci_writel(host, CR, MCI_CR_SWRST);
@@ -1408,7 +1409,8 @@ static irqreturn_t atmci_interrupt(int irq, void *dev_id)
                if (pending & MCI_NOTBUSY) {
                        mci_writel(host, IDR,
                                        ATMCI_DATA_ERROR_FLAGS | MCI_NOTBUSY);
-                       host->data_status = status;
+                       if (!host->data_status)
+                               host->data_status = status;
                        smp_wmb();
                        atmci_set_pending(host, EVENT_DATA_COMPLETE);
                        tasklet_schedule(&host->tasklet);