diff mbox series

[2/2] media: camss: Split power domain management

Message ID 20220704221548.629302-3-vladimir.zapolskiy@linaro.org
State Accepted
Commit 46cc031754985ee24034d55687540adb079f8630
Headers show
Series media: camss: Simplify and improve power management of VFEs | expand

Commit Message

Vladimir Zapolskiy July 4, 2022, 10:15 p.m. UTC
There are three cases of power domain management on supported platforms:
1) CAMSS on MSM8916, where a single VFE power domain is operated outside
   of the camss device driver,
2) CAMSS on MSM8996 and SDM630/SDM660, where two VFE power domains are
   managed separately by the camss device driver, the power domains are
   linked and unlinked on demand by their functions vfe_pm_domain_on()
   and vfe_pm_domain_off() respectively,
3) CAMSS on SDM845 and SM8250 platforms, and there are two VFE power
   domains and their parent power domain TITAN_TOP, the latter one
   shall be turned on prior to turning on any of VFE power domains.

Due to a previously missing link between TITAN_TOP and VFEx power domains
in the latter case, which is now fixed by [1], it was decided always to
turn on all found VFE power domains and TITAN_TOP power domain, even if
just one particular VFE is needed to be enabled or none of VFE power domains
are required, for instance the latter case is when vfe_lite is in use.
This misusage becomes more incovenient and clumsy, if next generations are
to be supported, for instance CAMSS on SM8450 has three VFE power domains.

The change splits the power management support for platforms with TITAN_TOP
parent power domain, and, since 'power-domain-names' property is not present
in camss device tree nodes, the assumption is that the first N power domains
from the 'power-domains' list correspond to VFE power domains, and, if the
number of power domains is greater than number of non-lite VFEs, then the
last power domain from the list is the TITAN_TOP power domain.

Signed-off-by: Vladimir Zapolskiy <vladimir.zapolskiy@linaro.org>
---
 .../media/platform/qcom/camss/camss-vfe-170.c | 20 ++++++++++++-
 .../media/platform/qcom/camss/camss-vfe-480.c | 20 ++++++++++++-
 drivers/media/platform/qcom/camss/camss.c     | 30 ++++++++++---------
 3 files changed, 54 insertions(+), 16 deletions(-)
diff mbox series

Patch

diff --git a/drivers/media/platform/qcom/camss/camss-vfe-170.c b/drivers/media/platform/qcom/camss/camss-vfe-170.c
index 600150cfc4f7..8e506a805d11 100644
--- a/drivers/media/platform/qcom/camss/camss-vfe-170.c
+++ b/drivers/media/platform/qcom/camss/camss-vfe-170.c
@@ -687,7 +687,12 @@  static void vfe_isr_wm_done(struct vfe_device *vfe, u8 wm)
  */
 static void vfe_pm_domain_off(struct vfe_device *vfe)
 {
-	/* nop */
+	struct camss *camss = vfe->camss;
+
+	if (vfe->id >= camss->vfe_num)
+		return;
+
+	device_link_del(camss->genpd_link[vfe->id]);
 }
 
 /*
@@ -696,6 +701,19 @@  static void vfe_pm_domain_off(struct vfe_device *vfe)
  */
 static int vfe_pm_domain_on(struct vfe_device *vfe)
 {
+	struct camss *camss = vfe->camss;
+	enum vfe_line_id id = vfe->id;
+
+	if (id >= camss->vfe_num)
+		return 0;
+
+	camss->genpd_link[id] = device_link_add(camss->dev, camss->genpd[id],
+						DL_FLAG_STATELESS |
+						DL_FLAG_PM_RUNTIME |
+						DL_FLAG_RPM_ACTIVE);
+	if (!camss->genpd_link[id])
+		return -EINVAL;
+
 	return 0;
 }
 
diff --git a/drivers/media/platform/qcom/camss/camss-vfe-480.c b/drivers/media/platform/qcom/camss/camss-vfe-480.c
index 129585110393..3aa962b5663b 100644
--- a/drivers/media/platform/qcom/camss/camss-vfe-480.c
+++ b/drivers/media/platform/qcom/camss/camss-vfe-480.c
@@ -494,7 +494,12 @@  static void vfe_isr_wm_done(struct vfe_device *vfe, u8 wm)
  */
 static void vfe_pm_domain_off(struct vfe_device *vfe)
 {
-	/* nop */
+	struct camss *camss = vfe->camss;
+
+	if (vfe->id >= camss->vfe_num)
+		return;
+
+	device_link_del(camss->genpd_link[vfe->id]);
 }
 
 /*
@@ -503,6 +508,19 @@  static void vfe_pm_domain_off(struct vfe_device *vfe)
  */
 static int vfe_pm_domain_on(struct vfe_device *vfe)
 {
+	struct camss *camss = vfe->camss;
+	enum vfe_line_id id = vfe->id;
+
+	if (id >= camss->vfe_num)
+		return 0;
+
+	camss->genpd_link[id] = device_link_add(camss->dev, camss->genpd[id],
+						DL_FLAG_STATELESS |
+						DL_FLAG_PM_RUNTIME |
+						DL_FLAG_RPM_ACTIVE);
+	if (!camss->genpd_link[id])
+		return -EINVAL;
+
 	return 0;
 }
 
diff --git a/drivers/media/platform/qcom/camss/camss.c b/drivers/media/platform/qcom/camss/camss.c
index 795eebd9af6c..f009297ba182 100644
--- a/drivers/media/platform/qcom/camss/camss.c
+++ b/drivers/media/platform/qcom/camss/camss.c
@@ -1453,7 +1453,6 @@  static const struct media_device_ops camss_media_ops = {
 static int camss_configure_pd(struct camss *camss)
 {
 	struct device *dev = camss->dev;
-	int last_pm_domain = 0;
 	int i;
 	int ret;
 
@@ -1484,32 +1483,34 @@  static int camss_configure_pd(struct camss *camss)
 	if (!camss->genpd_link)
 		return -ENOMEM;
 
+	/*
+	 * VFE power domains are in the beginning of the list, and while all
+	 * power domains should be attached, only if TITAN_TOP power domain is
+	 * found in the list, it should be linked over here.
+	 */
 	for (i = 0; i < camss->genpd_num; i++) {
 		camss->genpd[i] = dev_pm_domain_attach_by_id(camss->dev, i);
 		if (IS_ERR(camss->genpd[i])) {
 			ret = PTR_ERR(camss->genpd[i]);
 			goto fail_pm;
 		}
+	}
 
-		camss->genpd_link[i] = device_link_add(camss->dev, camss->genpd[i],
-						       DL_FLAG_STATELESS | DL_FLAG_PM_RUNTIME |
-						       DL_FLAG_RPM_ACTIVE);
-		if (!camss->genpd_link[i]) {
-			dev_pm_domain_detach(camss->genpd[i], true);
+	if (i > camss->vfe_num) {
+		camss->genpd_link[i - 1] = device_link_add(camss->dev, camss->genpd[i - 1],
+							   DL_FLAG_STATELESS | DL_FLAG_PM_RUNTIME |
+							   DL_FLAG_RPM_ACTIVE);
+		if (!camss->genpd_link[i - 1]) {
 			ret = -EINVAL;
 			goto fail_pm;
 		}
-
-		last_pm_domain = i;
 	}
 
 	return 0;
 
 fail_pm:
-	for (i = 0; i < last_pm_domain; i++) {
-		device_link_del(camss->genpd_link[i]);
+	for (--i ; i >= 0; i--)
 		dev_pm_domain_detach(camss->genpd[i], true);
-	}
 
 	return ret;
 }
@@ -1711,10 +1712,11 @@  void camss_delete(struct camss *camss)
 	if (camss->genpd_num == 1)
 		return;
 
-	for (i = 0; i < camss->genpd_num; i++) {
-		device_link_del(camss->genpd_link[i]);
+	if (camss->genpd_num > camss->vfe_num)
+		device_link_del(camss->genpd_link[camss->genpd_num - 1]);
+
+	for (i = 0; i < camss->genpd_num; i++)
 		dev_pm_domain_detach(camss->genpd[i], true);
-	}
 }
 
 /*