[PATCH 4.8 19/92] mmc: sdhci: Fix unexpected data interrupt handling

[Greg Kroah-Hartman]

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

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

From: Adrian Hunter <adrian.hunter@xxxxxxxxx>

commit 69b962a65a547690a356f9f76bc4f53db538ac49 upstream.

In the busy response case (i.e. !host->data), an unexpected data interrupt
would result in clearing the data command as though it had completed but
without informing the upper layers and thus resulting in a hang.  Fix by
only clearing the data command for data interrupts that are expected.

Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/mmc/host/sdhci.c |    5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -2509,9 +2509,6 @@ static void sdhci_data_irq(struct sdhci_
 	if (!host->data) {
 		struct mmc_command *data_cmd = host->data_cmd;
 
-		if (data_cmd)
-			host->data_cmd = NULL;
-
 		/*
 		 * The "data complete" interrupt is also used to
 		 * indicate that a busy state has ended. See comment
@@ -2519,11 +2516,13 @@ static void sdhci_data_irq(struct sdhci_
 		 */
 		if (data_cmd && (data_cmd->flags & MMC_RSP_BUSY)) {
 			if (intmask & SDHCI_INT_DATA_TIMEOUT) {
+				host->data_cmd = NULL;
 				data_cmd->error = -ETIMEDOUT;
 				sdhci_finish_mrq(host, data_cmd->mrq);
 				return;
 			}
 			if (intmask & SDHCI_INT_DATA_END) {
+				host->data_cmd = NULL;
 				/*
 				 * Some cards handle busy-end interrupt
 				 * before the command completed, so make