[PATCH v5 1/2] PM / Domains: Add GENPD_FLAG_RPM_ALWAYS_ON flag

[Leonard Crestez <leonard.crestez@nxp.com>]

This is for power domains which can only be powered off for suspend but
not as part of runtime PM.

Suggested-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
---
 drivers/base/power/domain.c | 8 ++++++--
 include/linux/pm_domain.h   | 4 ++++
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 7a6aa2318915..33c30c1e6a30 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -126,10 +126,11 @@ static const struct genpd_lock_ops genpd_spin_ops = {
 #define genpd_status_on(genpd)		(genpd->status == GPD_STATE_ACTIVE)
 #define genpd_is_irq_safe(genpd)	(genpd->flags & GENPD_FLAG_IRQ_SAFE)
 #define genpd_is_always_on(genpd)	(genpd->flags & GENPD_FLAG_ALWAYS_ON)
 #define genpd_is_active_wakeup(genpd)	(genpd->flags & GENPD_FLAG_ACTIVE_WAKEUP)
 #define genpd_is_cpu_domain(genpd)	(genpd->flags & GENPD_FLAG_CPU_DOMAIN)
+#define genpd_is_rpm_always_on(genpd)	(genpd->flags & GENPD_FLAG_RPM_ALWAYS_ON)
 
 static inline bool irq_safe_dev_in_no_sleep_domain(struct device *dev,
 		const struct generic_pm_domain *genpd)
 {
 	bool ret;
@@ -513,11 +514,13 @@ static int genpd_power_off(struct generic_pm_domain *genpd, bool one_dev_on,
 	/*
 	 * Abort power off for the PM domain in the following situations:
 	 * (1) The domain is configured as always on.
 	 * (2) When the domain has a subdomain being powered on.
 	 */
-	if (genpd_is_always_on(genpd) || atomic_read(&genpd->sd_count) > 0)
+	if (genpd_is_always_on(genpd) ||
+			genpd_is_rpm_always_on(genpd) ||
+			atomic_read(&genpd->sd_count) > 0)
 		return -EBUSY;
 
 	list_for_each_entry(pdd, &genpd->dev_list, list_node) {
 		enum pm_qos_flags_status stat;
 
@@ -1810,11 +1813,12 @@ int pm_genpd_init(struct generic_pm_domain *genpd,
 		genpd->dev_ops.stop = pm_clk_suspend;
 		genpd->dev_ops.start = pm_clk_resume;
 	}
 
 	/* Always-on domains must be powered on at initialization. */
-	if (genpd_is_always_on(genpd) && !genpd_status_on(genpd))
+	if ((genpd_is_always_on(genpd) || genpd_is_rpm_always_on(genpd)) &&
+			!genpd_status_on(genpd))
 		return -EINVAL;
 
 	if (genpd_is_cpu_domain(genpd) &&
 	    !zalloc_cpumask_var(&genpd->cpus, GFP_KERNEL))
 		return -ENOMEM;
diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h
index 0e8e356bed6a..b21f35f0ee2e 100644
--- a/include/linux/pm_domain.h
+++ b/include/linux/pm_domain.h
@@ -51,16 +51,20 @@
  *				deploy idle power management support for CPUs
  *				and groups of CPUs. Note that, the backend
  *				driver must then comply with the so called,
  *				last-man-standing algorithm, for the CPUs in the
  *				PM domain.
+ *
+ * GENPD_FLAG_RPM_ALWAYS_ON:	Instructs genpd to always keep the PM domain
+ *				powered on except for system suspend.
  */
 #define GENPD_FLAG_PM_CLK	 (1U << 0)
 #define GENPD_FLAG_IRQ_SAFE	 (1U << 1)
 #define GENPD_FLAG_ALWAYS_ON	 (1U << 2)
 #define GENPD_FLAG_ACTIVE_WAKEUP (1U << 3)
 #define GENPD_FLAG_CPU_DOMAIN	 (1U << 4)
+#define GENPD_FLAG_RPM_ALWAYS_ON (1U << 5)
 
 enum gpd_status {
 	GPD_STATE_ACTIVE = 0,	/* PM domain is active */
 	GPD_STATE_POWER_OFF,	/* PM domain is off */
 };
-- 
2.17.1