PM / domains: Add pd_ignore_unused to keep power domains enabled
Keep all power-domains already enabled by bootloader on, even if no
driver has claimed them. This is useful for debug and development, but
should not be needed on a platform with proper driver support.
Signed-off-by: Tushar Behera <tushar.behera@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index bc34785..d4aff40 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -2558,6 +2558,13 @@
pcmv= [HW,PCMCIA] BadgePAD 4
+ pd_ignore_unused
+ [PM]
+ Keep all power-domains already enabled by bootloader on,
+ even if no driver has claimed them. This is useful
+ for debug and development, but should not be
+ needed on a platform with proper driver support.
+
pd. [PARIDE]
See Documentation/blockdev/paride.txt.
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 6f54962..ae098a2 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -705,6 +705,14 @@
return 0;
}
+static bool pd_ignore_unused;
+static int __init pd_ignore_unused_setup(char *__unused)
+{
+ pd_ignore_unused = true;
+ return 1;
+}
+__setup("pd_ignore_unused", pd_ignore_unused_setup);
+
/**
* pm_genpd_poweroff_unused - Power off all PM domains with no devices in use.
*/
@@ -712,6 +720,11 @@
{
struct generic_pm_domain *genpd;
+ if (pd_ignore_unused) {
+ pr_warn("genpd: Not disabling unused power domains\n");
+ return;
+ }
+
mutex_lock(&gpd_list_lock);
list_for_each_entry(genpd, &gpd_list, gpd_list_node)