linux/drivers/misc/pvpanic.c
Andy Shevchenko afded6d83a misc: pvpanic: Check devm_ioport_map() for NULL
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: f104060813 ("misc: pvpanic: Combine ACPI and platform drivers")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20201228184313.57610-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07 20:28:01 +01:00

112 lines
2.3 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Pvpanic Device Support
*
* Copyright (C) 2013 Fujitsu.
* Copyright (C) 2018 ZTE.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/kexec.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/types.h>
#include <uapi/misc/pvpanic.h>
static void __iomem *base;
MODULE_AUTHOR("Hu Tao <hutao@cn.fujitsu.com>");
MODULE_DESCRIPTION("pvpanic device driver");
MODULE_LICENSE("GPL");
static void
pvpanic_send_event(unsigned int event)
{
iowrite8(event, base);
}
static int
pvpanic_panic_notify(struct notifier_block *nb, unsigned long code,
void *unused)
{
unsigned int event = PVPANIC_PANICKED;
if (kexec_crash_loaded())
event = PVPANIC_CRASH_LOADED;
pvpanic_send_event(event);
return NOTIFY_DONE;
}
static struct notifier_block pvpanic_panic_nb = {
.notifier_call = pvpanic_panic_notify,
.priority = 1, /* let this called before broken drm_fb_helper */
};
static int pvpanic_mmio_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct resource *res;
res = platform_get_mem_or_io(pdev, 0);
if (!res)
return -EINVAL;
switch (resource_type(res)) {
case IORESOURCE_IO:
base = devm_ioport_map(dev, res->start, resource_size(res));
if (!base)
return -ENOMEM;
break;
case IORESOURCE_MEM:
base = devm_ioremap_resource(dev, res);
if (IS_ERR(base))
return PTR_ERR(base);
break;
default:
return -EINVAL;
}
atomic_notifier_chain_register(&panic_notifier_list,
&pvpanic_panic_nb);
return 0;
}
static int pvpanic_mmio_remove(struct platform_device *pdev)
{
atomic_notifier_chain_unregister(&panic_notifier_list,
&pvpanic_panic_nb);
return 0;
}
static const struct of_device_id pvpanic_mmio_match[] = {
{ .compatible = "qemu,pvpanic-mmio", },
{}
};
static const struct acpi_device_id pvpanic_device_ids[] = {
{ "QEMU0001", 0 },
{ "", 0 }
};
MODULE_DEVICE_TABLE(acpi, pvpanic_device_ids);
static struct platform_driver pvpanic_mmio_driver = {
.driver = {
.name = "pvpanic-mmio",
.of_match_table = pvpanic_mmio_match,
.acpi_match_table = pvpanic_device_ids,
},
.probe = pvpanic_mmio_probe,
.remove = pvpanic_mmio_remove,
};
module_platform_driver(pvpanic_mmio_driver);