rfkill: export persistent attribute in sysfs
This information allows userspace to implement a hybrid policy where
it can store the rfkill soft-blocked state in platform non-volatile
storage if available, and if not then file-based storage can be used.
Some users prefer platform non-volatile storage because of the behaviour
when dual-booting multiple versions of Linux, or if the rfkill setting
is changed in the BIOS setting screens, or if the BIOS responds to
wireless-toggle hotkeys itself before the relevant platform driver has
been loaded.
Signed-off-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Acked-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/Documentation/rfkill.txt b/Documentation/rfkill.txt
index c8acd86..b486050 100644
--- a/Documentation/rfkill.txt
+++ b/Documentation/rfkill.txt
@@ -111,6 +111,8 @@
name: Name assigned by driver to this key (interface or driver name).
type: Driver type string ("wlan", "bluetooth", etc).
+ persistent: Whether the soft blocked state is initialised from
+ non-volatile storage at startup.
state: Current state of the transmitter
0: RFKILL_STATE_SOFT_BLOCKED
transmitter is turned off by software
diff --git a/include/linux/rfkill.h b/include/linux/rfkill.h
index dcac724..e73e242 100644
--- a/include/linux/rfkill.h
+++ b/include/linux/rfkill.h
@@ -259,8 +259,9 @@
* userspace) of their initial state. It should only be used before
* registration.
*
- * In addition, it marks the device as "persistent". Persistent devices
- * are expected to preserve preserve their own state when suspended.
+ * In addition, it marks the device as "persistent", an attribute which
+ * can be read by userspace. Persistent devices are expected to preserve
+ * their own state when suspended.
*/
void rfkill_init_sw_state(struct rfkill *rfkill, bool blocked);
diff --git a/net/rfkill/core.c b/net/rfkill/core.c
index dcf8df7..79693fe 100644
--- a/net/rfkill/core.c
+++ b/net/rfkill/core.c
@@ -610,6 +610,15 @@
return sprintf(buf, "%d\n", rfkill->idx);
}
+static ssize_t rfkill_persistent_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct rfkill *rfkill = to_rfkill(dev);
+
+ return sprintf(buf, "%d\n", rfkill->persistent);
+}
+
static u8 user_state_from_blocked(unsigned long state)
{
if (state & RFKILL_BLOCK_HW)
@@ -668,6 +677,7 @@
__ATTR(name, S_IRUGO, rfkill_name_show, NULL),
__ATTR(type, S_IRUGO, rfkill_type_show, NULL),
__ATTR(index, S_IRUGO, rfkill_idx_show, NULL),
+ __ATTR(persistent, S_IRUGO, rfkill_persistent_show, NULL),
__ATTR(state, S_IRUGO|S_IWUSR, rfkill_state_show, rfkill_state_store),
__ATTR(claim, S_IRUGO|S_IWUSR, rfkill_claim_show, rfkill_claim_store),
__ATTR_NULL