[PATCH 4.14 183/323] pata_arasan_cf: fix IRQ check

From: Greg Kroah-Hartman
Date: Thu May 20 2021 - 06:44:52 EST


From: Sergey Shtylyov <s.shtylyov@xxxxxxxxxxxx>

[ Upstream commit c7e8f404d56b99c80990b19a402c3f640d74be05 ]

The driver's probe() method is written as if platform_get_irq() returns 0
on error, while actually it returns a negative error code (with all the
other values considered valid IRQs). Rewrite the driver's IRQ checking code
to pass the positive IRQ #s to ata_host_activate(), propagate upstream
-EPROBE_DEFER, and set up the driver to polling mode on (negative) errors
and IRQ0 (libata treats IRQ #0 as a polling mode anyway)...

Fixes: a480167b23ef ("pata_arasan_cf: Adding support for arasan compact flash host controller")
Signed-off-by: Sergey Shtylyov <s.shtylyov@xxxxxxxxxxxx>
Acked-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/ata/pata_arasan_cf.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/ata/pata_arasan_cf.c b/drivers/ata/pata_arasan_cf.c
index b4d54771c9fe..623199fab8fe 100644
--- a/drivers/ata/pata_arasan_cf.c
+++ b/drivers/ata/pata_arasan_cf.c
@@ -819,12 +819,19 @@ static int arasan_cf_probe(struct platform_device *pdev)
else
quirk = CF_BROKEN_UDMA; /* as it is on spear1340 */

- /* if irq is 0, support only PIO */
- acdev->irq = platform_get_irq(pdev, 0);
- if (acdev->irq)
+ /*
+ * If there's an error getting IRQ (or we do get IRQ0),
+ * support only PIO
+ */
+ ret = platform_get_irq(pdev, 0);
+ if (ret > 0) {
+ acdev->irq = ret;
irq_handler = arasan_cf_interrupt;
- else
+ } else if (ret == -EPROBE_DEFER) {
+ return ret;
+ } else {
quirk |= CF_BROKEN_MWDMA | CF_BROKEN_UDMA;
+ }

acdev->pbase = res->start;
acdev->vbase = devm_ioremap_nocache(&pdev->dev, res->start,
--
2.30.2