[PATCH v1] misc: pvpanic: Check devm_ioport_map() for NULL

From: Andy Shevchenko
Date: Mon Dec 28 2020 - 13:45:20 EST


Inconveniently devm_ioport_map() and devm_ioremap_resource()
return errors differently, i.e. former uses simply NULL pointer,
while the latter an error pointer.

Due to this, we have to check each of them separately.

Fixes: f104060813fe ("misc: pvpanic: Combine ACPI and platform drivers")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
drivers/misc/pvpanic.c | 19 +++++++++++++++----
1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/drivers/misc/pvpanic.c b/drivers/misc/pvpanic.c
index 951b37da5e3c..41cab297d66e 100644
--- a/drivers/misc/pvpanic.c
+++ b/drivers/misc/pvpanic.c
@@ -55,12 +55,23 @@ static int pvpanic_mmio_probe(struct platform_device *pdev)
struct resource *res;

res = platform_get_mem_or_io(pdev, 0);
- if (res && resource_type(res) == IORESOURCE_IO)
+ if (!res)
+ return -EINVAL;
+
+ switch (resource_type(res)) {
+ case IORESOURCE_IO:
base = devm_ioport_map(dev, res->start, resource_size(res));
- else
+ if (!base)
+ return -ENOMEM;
+ break;
+ case IORESOURCE_MEM:
base = devm_ioremap_resource(dev, res);
- if (IS_ERR(base))
- return PTR_ERR(base);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+ break;
+ default:
+ return -EINVAL;
+ }

atomic_notifier_chain_register(&panic_notifier_list,
&pvpanic_panic_nb);
--
2.29.2