Current reboot-mode driver supports a single argument(magic) for
each reboot-mode. There may be uses-cases where a mode requires
an additional argument and hence may not be able to use the
reboot-mode driver. For example, ARM PSCI vendor-specific resets,
need two arguments for its operation – reset_type and cookie, to
complete the reset operation. If a driver wants to implement this
firmware-based reset, it cannot use reboot-mode framework.
Add support for storing an additional optional argument (cookie)
for each reboot-mode and introduce a write function in
reboot-mode that writes two arguments for each reboot-mode
command. Implement the read and store of additional cookie value
for each reboot-mode defined in the device tree. In case there is
no cookie specified in the reboot-mode device tree, mark the
cookie as invalid to support backward compatibility.
Signed-off-by: Shivendra Pratap <shivendra.pratap@xxxxxxxxxxxxxxxx>
---
drivers/power/reset/reboot-mode.c | 32 ++++++++++++++++++++++----------
include/linux/reboot-mode.h | 2 ++
2 files changed, 24 insertions(+), 10 deletions(-)
diff --git a/drivers/power/reset/reboot-mode.c b/drivers/power/reset/reboot-mode.c
index 61f647b23959789a313f3af0bd967abcad45fa43..afadd823d62d0f7e7e645746b978cc8fecfb9ac4 100644
--- a/drivers/power/reset/reboot-mode.c
+++ b/drivers/power/reset/reboot-mode.c
@@ -17,11 +17,12 @@
struct mode_info {
const char *mode;
u32 magic;
+ u32 cookie;
+ bool is_cookie_valid;
struct list_head list;
};
-static unsigned int get_reboot_mode_magic(struct reboot_mode_driver *reboot,
- const char *cmd)
+static struct mode_info *get_reboot_mode_info(struct reboot_mode_driver *reboot, const char *cmd)
{
const char *normal = "normal";
struct mode_info *info;
@@ -32,11 +33,11 @@ static unsigned int get_reboot_mode_magic(struct reboot_mode_driver *reboot,
list_for_each_entry(info, &reboot->head, list)
if (!strcmp(info->mode, cmd))
- return info->magic;
+ return info;
/* try to match again, replacing characters impossible in DT */
if (strscpy(cmd_, cmd, sizeof(cmd_)) == -E2BIG)
- return 0;
+ return NULL;
strreplace(cmd_, ' ', '-');
strreplace(cmd_, ',', '-');
@@ -44,21 +45,27 @@ static unsigned int get_reboot_mode_magic(struct reboot_mode_driver *reboot,
list_for_each_entry(info, &reboot->head, list)
if (!strcmp(info->mode, cmd_))
- return info->magic;
+ return info;
- return 0;
+ return NULL;
}
static int reboot_mode_notify(struct notifier_block *this,
unsigned long mode, void *cmd)
{
struct reboot_mode_driver *reboot;
- unsigned int magic;
+ struct mode_info *info;
reboot = container_of(this, struct reboot_mode_driver, reboot_notifier);
- magic = get_reboot_mode_magic(reboot, cmd);
- if (magic)
- reboot->write(reboot, magic);
+ info = get_reboot_mode_info(reboot, cmd);
+ if (info) {
+ if (info->is_cookie_valid) {
+ reboot->write_with_cookie(reboot, info->magic, info->cookie);
+ } else {
+ if (info->magic)
+ reboot->write(reboot, info->magic);
+ }
+ }
return NOTIFY_DONE;
}
@@ -95,6 +102,11 @@ int reboot_mode_register(struct reboot_mode_driver *reboot, struct device_node *
continue;
}
+ if (of_property_read_u32_index(np, prop->name, 1, &info->cookie))
+ info->is_cookie_valid = false;
+ else
+ info->is_cookie_valid = true;
+
info->mode = kstrdup_const(prop->name + len, GFP_KERNEL);
if (!info->mode) {
ret = -ENOMEM;
diff --git a/include/linux/reboot-mode.h b/include/linux/reboot-mode.h
index 36f071f4b82e1fc255d8dd679a18e537655c3179..cfe18cdc2559be249969bba6c022940a508dd188 100644
--- a/include/linux/reboot-mode.h
+++ b/include/linux/reboot-mode.h
@@ -6,6 +6,8 @@ struct reboot_mode_driver {
struct device *dev;
struct list_head head;
int (*write)(struct reboot_mode_driver *reboot, unsigned int magic);
+ int (*write_with_cookie)(struct reboot_mode_driver *reboot,
+ unsigned int magic, unsigned int cookie);
struct notifier_block reboot_notifier;
};
--
2.34.1
