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#include <linux/err.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/reboot.h>
/* Types of reasons */
enum {
NONE,
BOOTLOADER,
RECOVERY,
OEM,
MAX_REASONS
};
static u32 reasons[MAX_REASONS];
static void __iomem *reboot_reason_val_addr;
static struct notifier_block reboot_nb;
static int reboot_reason(struct notifier_block *nb, unsigned long action,
void *data)
{
char *cmd = (char *)data;
u32 reason = reasons[NONE];
if (!reboot_reason_val_addr)
return NOTIFY_DONE;
if (cmd != NULL) {
if (!strncmp(cmd, "bootloader", 10))
reason = reasons[BOOTLOADER];
else if (!strncmp(cmd, "recovery", 8))
reason = reasons[RECOVERY];
else if (!strncmp(cmd, "oem-", 4)) {
unsigned long code;
if (!kstrtoul(cmd+4, 0, &code))
reason = reasons[OEM] | (code & 0xff);
}
}
if (reason != -1)
writel(reason, reboot_reason_val_addr);
return NOTIFY_DONE;
}
static int reboot_reason_probe(struct platform_device *pdev)
{
struct resource *res;
u32 val;
int i;
/* initialize the reasons */
for (i = 0; i < MAX_REASONS; i++)
reasons[i] = -1;
/* Try to grab the reason io address */
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
reboot_reason_val_addr = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(reboot_reason_val_addr))
return PTR_ERR(reboot_reason_val_addr);
/* initialize specified reasons from DT */
if (!of_property_read_u32(pdev->dev.of_node, "reason,none", &val))
reasons[NONE] = val;
if (!of_property_read_u32(pdev->dev.of_node, "reason,bootloader", &val))
reasons[BOOTLOADER] = val;
if (!of_property_read_u32(pdev->dev.of_node, "reason,recovery", &val))
reasons[RECOVERY] = val;
if (!of_property_read_u32(pdev->dev.of_node, "reason,oem", &val))
reasons[OEM] = val;
/* Install the notifier */
reboot_nb.notifier_call = reboot_reason;
reboot_nb.priority = 256;
if (register_reboot_notifier(&reboot_nb)) {
dev_err(&pdev->dev,
"failed to setup restart handler.\n");
}
return 0;
}
int reboot_reason_remove(struct platform_device *pdev)
{
unregister_reboot_notifier(&reboot_nb);
return 0;
}
static const struct of_device_id reboot_reason_of_match[] = {
{ .compatible = "linux,reboot-reason-sram", },
{ },
};
MODULE_DEVICE_TABLE(of, reboot_reason_of_match);
static struct platform_driver reboot_reason_driver = {
.driver = {
.name = "reboot-reason-sram",
.of_match_table = reboot_reason_of_match,
},
.probe = reboot_reason_probe,
.remove = reboot_reason_remove,
};
module_platform_driver(reboot_reason_driver);
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