[PATCH 4.14 54/91] scsi: ufs: Improve interrupt handling for shared interrupts

Greg Kroah-Hartman
2020-09-01T17:05:29Z

From: Adrian Hunter <adrian.hunter@intel.com>

[ Upstream commit 127d5f7c4b653b8be5eb3b2c7bbe13728f9003ff ]

For shared interrupts, the interrupt status might be zero, so check that
first.

Link: https://lore.kernel.org/r/20200811133936.19171-2-adrian.hunter@intel.com
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/scsi/ufs/ufshcd.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 3b4214feae971..619fe46fcc5f0 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -5373,7 +5373,7 @@ static void ufshcd_sl_intr(struct ufs_hba *hba, u32 intr_status)
*/
static irqreturn_t ufshcd_intr(int irq, void *__hba)
{
- u32 intr_status, enabled_intr_status;
+ u32 intr_status, enabled_intr_status = 0;
irqreturn_t retval = IRQ_NONE;
struct ufs_hba *hba = __hba;
int retries = hba->nutrs;
@@ -5387,7 +5387,7 @@ static irqreturn_t ufshcd_intr(int irq, void *__hba)
* read, make sure we handle them by checking the interrupt status
* again in a loop until we process all of the reqs before returning.
*/
- do {
+ while (intr_status && retries--) {
enabled_intr_status =
intr_status & ufshcd_readl(hba, REG_INTERRUPT_ENABLE);
if (intr_status)
@@ -5398,7 +5398,7 @@ static irqreturn_t ufshcd_intr(int irq, void *__hba)
}

intr_status = ufshcd_readl(hba, REG_INTERRUPT_STATUS);
- } while (intr_status && --retries);
+ }

spin_unlock(hba->host->host_lock);
return retval;
--
2.25.1