[PATCH 0/4] media: qcom: camss: Introduce support for named power-domains

[PATCH 0/4] media: qcom: camss: Introduce support for named power-domains

[Bryan O'Donoghue]

At the moment the Qcom CAMSS driver relies on the declaration order of
power-domains within the dtsi to determine which power-domain relates to a
VFE and which power-domain relates to the top-level (top) CAMSS
power-domain.

VFE power-domains must be declared prior to the top power-domain. The top
power-domain must be declared last. Early SoCs have just one top
power-domain with later SoCs introducing VFE specific power-domains.

Differentiating between the number of power-domains results in lots of code
which is brittle and which we can mostly get rid of with named
power-domains.

The reliance on declaration ordering is in-effect magic number indexing.

This series introduces named power-domains for CAMSS and refactors some of
the code in CAMSS to support the new named power-domains. We continue to
support the legacy indexing model with an intention to remove after a
reasonable transition period.

New SoC additions should use named power-domains from now on.

Tested on x13s, rb5, db410c

Link: https://git.codelinaro.org/bryan.odonoghue/kernel/-/tree/linux-next-23-10-23-camss-named-power-domains

Bryan O'Donoghue (4):
  media: qcom: camss: Convert to per-VFE pointer for power-domain
    linkages
  media: qcom: camss: Use common VFE pm_domain_on/pm_domain_off where
    applicable
  media: qcom: camss: Move VFE power-domain specifics into vfe.c
  media: qcom: camss: Add support for named power-domains

 .../media/platform/qcom/camss/camss-vfe-170.c | 36 ---------
 .../media/platform/qcom/camss/camss-vfe-4-1.c |  8 +-
 .../media/platform/qcom/camss/camss-vfe-4-7.c | 36 ---------
 .../media/platform/qcom/camss/camss-vfe-4-8.c | 31 --------
 .../media/platform/qcom/camss/camss-vfe-480.c | 36 ---------
 drivers/media/platform/qcom/camss/camss-vfe.c | 79 +++++++++++++++++++
 drivers/media/platform/qcom/camss/camss-vfe.h | 16 ++++
 drivers/media/platform/qcom/camss/camss.c     | 79 +++++++++++--------
 drivers/media/platform/qcom/camss/camss.h     |  6 +-
 9 files changed, 149 insertions(+), 178 deletions(-)

-- 
2.42.0

[PATCH 1/4] media: qcom: camss: Convert to per-VFE pointer for power-domain linkages

[Bryan O'Donoghue]

Right now we use the top-level camss structure to provide pointers via
VFE id index back to genpd linkages.

In effect this hard-codes VFE indexes to power-domain indexes in the
dtsi and mandates a very particular ordering of power domains in the
dtsi, which bears no relationship to a real hardware dependency.

As a first step to rationalising the VFE power-domain code and breaking
the magic indexing in dtsi use per-VFE pointers to genpd linkages.

The top-level index in msm_vfe_subdev_init is still used to attain the
initial so no functional or logical change arises from this change.

Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
---
 drivers/media/platform/qcom/camss/camss-vfe-170.c | 12 ++++++------
 drivers/media/platform/qcom/camss/camss-vfe-4-7.c | 12 ++++--------
 drivers/media/platform/qcom/camss/camss-vfe-4-8.c | 10 ++++------
 drivers/media/platform/qcom/camss/camss-vfe-480.c | 12 ++++++------
 drivers/media/platform/qcom/camss/camss-vfe.c     |  3 +++
 drivers/media/platform/qcom/camss/camss-vfe.h     |  2 ++
 6 files changed, 25 insertions(+), 26 deletions(-)

diff --git a/drivers/media/platform/qcom/camss/camss-vfe-170.c b/drivers/media/platform/qcom/camss/camss-vfe-170.c
index 0b211fed12760..59b0ea0aac48f 100644
--- a/drivers/media/platform/qcom/camss/camss-vfe-170.c
+++ b/drivers/media/platform/qcom/camss/camss-vfe-170.c
@@ -638,7 +638,7 @@ static void vfe_pm_domain_off(struct vfe_device *vfe)
 	if (vfe->id >= camss->res->vfe_num)
 		return;
 
-	device_link_del(camss->genpd_link[vfe->id]);
+	device_link_del(vfe->genpd_link);
 }
 
 /*
@@ -653,11 +653,11 @@ static int vfe_pm_domain_on(struct vfe_device *vfe)
 	if (id >= camss->res->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])
+	vfe->genpd_link = device_link_add(camss->dev, vfe->genpd,
+					  DL_FLAG_STATELESS |
+					  DL_FLAG_PM_RUNTIME |
+					  DL_FLAG_RPM_ACTIVE);
+	if (!vfe->genpd_link)
 		return -EINVAL;
 
 	return 0;
diff --git a/drivers/media/platform/qcom/camss/camss-vfe-4-7.c b/drivers/media/platform/qcom/camss/camss-vfe-4-7.c
index b65ed0fef595e..c668494ee1e98 100644
--- a/drivers/media/platform/qcom/camss/camss-vfe-4-7.c
+++ b/drivers/media/platform/qcom/camss/camss-vfe-4-7.c
@@ -1109,14 +1109,10 @@ static void vfe_isr_read(struct vfe_device *vfe, u32 *value0, u32 *value1)
  */
 static void vfe_pm_domain_off(struct vfe_device *vfe)
 {
-	struct camss *camss;
-
 	if (!vfe)
 		return;
 
-	camss = vfe->camss;
-
-	device_link_del(camss->genpd_link[vfe->id]);
+	device_link_del(vfe->genpd_link);
 }
 
 /*
@@ -1128,10 +1124,10 @@ static int vfe_pm_domain_on(struct vfe_device *vfe)
 	struct camss *camss = vfe->camss;
 	enum vfe_line_id id = vfe->id;
 
-	camss->genpd_link[id] = device_link_add(camss->dev, camss->genpd[id], DL_FLAG_STATELESS |
-						DL_FLAG_PM_RUNTIME | DL_FLAG_RPM_ACTIVE);
+	vfe->genpd_link = device_link_add(camss->dev, vfe->genpd, DL_FLAG_STATELESS |
+					  DL_FLAG_PM_RUNTIME | DL_FLAG_RPM_ACTIVE);
 
-	if (!camss->genpd_link[id]) {
+	if (!vfe->genpd_link) {
 		dev_err(vfe->camss->dev, "Failed to add VFE#%d to power domain\n", id);
 		return -EINVAL;
 	}
diff --git a/drivers/media/platform/qcom/camss/camss-vfe-4-8.c b/drivers/media/platform/qcom/camss/camss-vfe-4-8.c
index 7b3805177f037..5bd5b6b3c992a 100644
--- a/drivers/media/platform/qcom/camss/camss-vfe-4-8.c
+++ b/drivers/media/platform/qcom/camss/camss-vfe-4-8.c
@@ -1099,9 +1099,7 @@ static void vfe_isr_read(struct vfe_device *vfe, u32 *value0, u32 *value1)
  */
 static void vfe_pm_domain_off(struct vfe_device *vfe)
 {
-	struct camss *camss = vfe->camss;
-
-	device_link_del(camss->genpd_link[vfe->id]);
+	device_link_del(vfe->genpd_link);
 }
 
 /*
@@ -1113,10 +1111,10 @@ static int vfe_pm_domain_on(struct vfe_device *vfe)
 	struct camss *camss = vfe->camss;
 	enum vfe_line_id id = vfe->id;
 
-	camss->genpd_link[id] = device_link_add(camss->dev, camss->genpd[id], DL_FLAG_STATELESS |
-						DL_FLAG_PM_RUNTIME | DL_FLAG_RPM_ACTIVE);
+	vfe->genpd_link = device_link_add(camss->dev, vfe->genpd, DL_FLAG_STATELESS |
+					  DL_FLAG_PM_RUNTIME | DL_FLAG_RPM_ACTIVE);
 
-	if (!camss->genpd_link[id]) {
+	if (!vfe->genpd_link) {
 		dev_err(vfe->camss->dev, "Failed to add VFE#%d to power domain\n", id);
 		return -EINVAL;
 	}
diff --git a/drivers/media/platform/qcom/camss/camss-vfe-480.c b/drivers/media/platform/qcom/camss/camss-vfe-480.c
index f2368b77fc6d6..ca16a7ebb2903 100644
--- a/drivers/media/platform/qcom/camss/camss-vfe-480.c
+++ b/drivers/media/platform/qcom/camss/camss-vfe-480.c
@@ -463,7 +463,7 @@ static void vfe_pm_domain_off(struct vfe_device *vfe)
 	if (vfe->id >= camss->res->vfe_num)
 		return;
 
-	device_link_del(camss->genpd_link[vfe->id]);
+	device_link_del(vfe->genpd_link);
 }
 
 /*
@@ -478,11 +478,11 @@ static int vfe_pm_domain_on(struct vfe_device *vfe)
 	if (id >= camss->res->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])
+	vfe->genpd_link = device_link_add(camss->dev, vfe->genpd,
+					  DL_FLAG_STATELESS |
+					  DL_FLAG_PM_RUNTIME |
+					  DL_FLAG_RPM_ACTIVE);
+	if (!vfe->genpd_link)
 		return -EINVAL;
 
 	return 0;
diff --git a/drivers/media/platform/qcom/camss/camss-vfe.c b/drivers/media/platform/qcom/camss/camss-vfe.c
index 4839e2cedfe58..3d31f4289b724 100644
--- a/drivers/media/platform/qcom/camss/camss-vfe.c
+++ b/drivers/media/platform/qcom/camss/camss-vfe.c
@@ -1347,6 +1347,9 @@ int msm_vfe_subdev_init(struct camss *camss, struct vfe_device *vfe,
 	if (!res->line_num)
 		return -EINVAL;
 
+	if (camss->genpd)
+		vfe->genpd = camss->genpd[id];
+
 	vfe->line_num = res->line_num;
 	vfe->ops->subdev_init(dev, vfe);
 
diff --git a/drivers/media/platform/qcom/camss/camss-vfe.h b/drivers/media/platform/qcom/camss/camss-vfe.h
index 09baded0dcdd6..c1c50023d4876 100644
--- a/drivers/media/platform/qcom/camss/camss-vfe.h
+++ b/drivers/media/platform/qcom/camss/camss-vfe.h
@@ -150,6 +150,8 @@ struct vfe_device {
 	const struct vfe_hw_ops_gen1 *ops_gen1;
 	struct vfe_isr_ops isr_ops;
 	struct camss_video_ops video_ops;
+	struct device *genpd;
+	struct device_link *genpd_link;
 };
 
 struct camss_subdev_resources;
-- 
2.42.0

Re: [PATCH 1/4] media: qcom: camss: Convert to per-VFE pointer for power-domain linkages

[Konrad Dybcio]

On 10/25/23 00:42, Bryan O'Donoghue wrote:
> Right now we use the top-level camss structure to provide pointers via
> VFE id index back to genpd linkages.
> 
> In effect this hard-codes VFE indexes to power-domain indexes in the
> dtsi and mandates a very particular ordering of power domains in the
> dtsi, which bears no relationship to a real hardware dependency.
> 
> As a first step to rationalising the VFE power-domain code and breaking
> the magic indexing in dtsi use per-VFE pointers to genpd linkages.
> 
> The top-level index in msm_vfe_subdev_init is still used to attain the
> initial so no functional or logical change arises from this change.
> 
> Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
> ---
[...]

> @@ -653,11 +653,11 @@ static int vfe_pm_domain_on(struct vfe_device *vfe)
>   	if (id >= camss->res->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);
Good opportunity to inilne vfe->id and get rid of a local var!

> -	if (!camss->genpd_link[id])
> +	vfe->genpd_link = device_link_add(camss->dev, vfe->genpd,
> +					  DL_FLAG_STATELESS |
> +					  DL_FLAG_PM_RUNTIME |
> +					  DL_FLAG_RPM_ACTIVE);
> +	if (!vfe->genpd_link)
>   		return -EINVAL;
>   
[...]

>   /*
> @@ -1128,10 +1124,10 @@ static int vfe_pm_domain_on(struct vfe_device *vfe)
>   	struct camss *camss = vfe->camss;
>   	enum vfe_line_id id = vfe->id;
>   
> -	camss->genpd_link[id] = device_link_add(camss->dev, camss->genpd[id], DL_FLAG_STATELESS |
> -						DL_FLAG_PM_RUNTIME | DL_FLAG_RPM_ACTIVE);
> +	vfe->genpd_link = device_link_add(camss->dev, vfe->genpd, DL_FLAG_STATELESS |
> +					  DL_FLAG_PM_RUNTIME | DL_FLAG_RPM_ACTIVE);
>   
> -	if (!camss->genpd_link[id]) {
> +	if (!vfe->genpd_link) {
>   		dev_err(vfe->camss->dev, "Failed to add VFE#%d to power domain\n", id);
>   		return -EINVAL;
And here

[...]

> @@ -1113,10 +1111,10 @@ static int vfe_pm_domain_on(struct vfe_device *vfe)
>   	struct camss *camss = vfe->camss;
>   	enum vfe_line_id id = vfe->id;
>   
> -	camss->genpd_link[id] = device_link_add(camss->dev, camss->genpd[id], DL_FLAG_STATELESS |
> -						DL_FLAG_PM_RUNTIME | DL_FLAG_RPM_ACTIVE);
> +	vfe->genpd_link = device_link_add(camss->dev, vfe->genpd, DL_FLAG_STATELESS |
> +					  DL_FLAG_PM_RUNTIME | DL_FLAG_RPM_ACTIVE);
>   
> -	if (!camss->genpd_link[id]) {
> +	if (!vfe->genpd_link) {
>   		dev_err(vfe->camss->dev, "Failed to add VFE#%d to power domain\n", id);
>   		return -EINVAL;
And here

[...]
>   
>   /*
> @@ -478,11 +478,11 @@ static int vfe_pm_domain_on(struct vfe_device *vfe)
>   	if (id >= camss->res->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])
> +	vfe->genpd_link = device_link_add(camss->dev, vfe->genpd,
> +					  DL_FLAG_STATELESS |
> +					  DL_FLAG_PM_RUNTIME |
> +					  DL_FLAG_RPM_ACTIVE);
And here


Konrad

Re: [PATCH 1/4] media: qcom: camss: Convert to per-VFE pointer for power-domain linkages

[Bryan O'Donoghue]

On 25/10/2023 10:16, Konrad Dybcio wrote:
>> @@ -653,11 +653,11 @@ static int vfe_pm_domain_on(struct vfe_device *vfe)
>>       if (id >= camss->res->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);
> Good opportunity to inilne vfe->id and get rid of a local var!

Yeah no objection to that, this is a progressive patchset so the index 
goes away in 1 or 2 patches later in the series anyway.

---
bod

[PATCH 2/4] media: qcom: camss: Use common VFE pm_domain_on/pm_domain_off where applicable

[Bryan O'Donoghue]

For the various versions of VFE we have a boiler-plate
pm_domain_on/pm_domain_off callback pair of the general form.

- Error check.
  Not always done but applicable to all.

- device_link_add (DL_FLAG_STATELESS | DL_FLAG_PM_RUNTIME |
                   DL_FLAG_RPM_ACTIVE);

- Error check returning -EINVAL on error.

- Return 0

Reduce the pattern down to a common callback. VFE 4.1 is a special case
which to me also indicates that it is worthwhile maintaining an indirection
for the vfe_pm_domain_{on|off} for now.

Otherwise lets chuck out a bunch of needlessly replicated code.

Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
---
 .../media/platform/qcom/camss/camss-vfe-170.c | 36 -------------------
 .../media/platform/qcom/camss/camss-vfe-4-1.c |  8 ++---
 .../media/platform/qcom/camss/camss-vfe-4-7.c | 32 -----------------
 .../media/platform/qcom/camss/camss-vfe-4-8.c | 29 ---------------
 .../media/platform/qcom/camss/camss-vfe-480.c | 36 -------------------
 drivers/media/platform/qcom/camss/camss-vfe.c | 34 ++++++++++++++++++
 drivers/media/platform/qcom/camss/camss-vfe.h | 12 +++++++
 7 files changed, 50 insertions(+), 137 deletions(-)

diff --git a/drivers/media/platform/qcom/camss/camss-vfe-170.c b/drivers/media/platform/qcom/camss/camss-vfe-170.c
index 59b0ea0aac48f..795ac3815339a 100644
--- a/drivers/media/platform/qcom/camss/camss-vfe-170.c
+++ b/drivers/media/platform/qcom/camss/camss-vfe-170.c
@@ -627,42 +627,6 @@ static void vfe_isr_wm_done(struct vfe_device *vfe, u8 wm)
 	spin_unlock_irqrestore(&vfe->output_lock, flags);
 }
 
-/*
- * vfe_pm_domain_off - Disable power domains specific to this VFE.
- * @vfe: VFE Device
- */
-static void vfe_pm_domain_off(struct vfe_device *vfe)
-{
-	struct camss *camss = vfe->camss;
-
-	if (vfe->id >= camss->res->vfe_num)
-		return;
-
-	device_link_del(vfe->genpd_link);
-}
-
-/*
- * vfe_pm_domain_on - Enable power domains specific to this VFE.
- * @vfe: VFE Device
- */
-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->res->vfe_num)
-		return 0;
-
-	vfe->genpd_link = device_link_add(camss->dev, vfe->genpd,
-					  DL_FLAG_STATELESS |
-					  DL_FLAG_PM_RUNTIME |
-					  DL_FLAG_RPM_ACTIVE);
-	if (!vfe->genpd_link)
-		return -EINVAL;
-
-	return 0;
-}
-
 /*
  * vfe_queue_buffer - Add empty buffer
  * @vid: Video device structure
diff --git a/drivers/media/platform/qcom/camss/camss-vfe-4-1.c b/drivers/media/platform/qcom/camss/camss-vfe-4-1.c
index 2911e4126e7ad..ef6b34c915df1 100644
--- a/drivers/media/platform/qcom/camss/camss-vfe-4-1.c
+++ b/drivers/media/platform/qcom/camss/camss-vfe-4-1.c
@@ -936,7 +936,7 @@ static irqreturn_t vfe_isr(int irq, void *dev)
  * vfe_pm_domain_off - Disable power domains specific to this VFE.
  * @vfe: VFE Device
  */
-static void vfe_pm_domain_off(struct vfe_device *vfe)
+static void vfe_4_1_pm_domain_off(struct vfe_device *vfe)
 {
 	/* nop */
 }
@@ -945,7 +945,7 @@ static void vfe_pm_domain_off(struct vfe_device *vfe)
  * vfe_pm_domain_on - Enable power domains specific to this VFE.
  * @vfe: VFE Device
  */
-static int vfe_pm_domain_on(struct vfe_device *vfe)
+static int vfe_4_1_pm_domain_on(struct vfe_device *vfe)
 {
 	return 0;
 }
@@ -999,8 +999,8 @@ const struct vfe_hw_ops vfe_ops_4_1 = {
 	.hw_version = vfe_hw_version,
 	.isr_read = vfe_isr_read,
 	.isr = vfe_isr,
-	.pm_domain_off = vfe_pm_domain_off,
-	.pm_domain_on = vfe_pm_domain_on,
+	.pm_domain_off = vfe_4_1_pm_domain_off,
+	.pm_domain_on = vfe_4_1_pm_domain_on,
 	.reg_update_clear = vfe_reg_update_clear,
 	.reg_update = vfe_reg_update,
 	.subdev_init = vfe_subdev_init,
diff --git a/drivers/media/platform/qcom/camss/camss-vfe-4-7.c b/drivers/media/platform/qcom/camss/camss-vfe-4-7.c
index c668494ee1e98..7655d22a9fda2 100644
--- a/drivers/media/platform/qcom/camss/camss-vfe-4-7.c
+++ b/drivers/media/platform/qcom/camss/camss-vfe-4-7.c
@@ -1103,38 +1103,6 @@ static void vfe_isr_read(struct vfe_device *vfe, u32 *value0, u32 *value1)
 	writel_relaxed(VFE_0_IRQ_CMD_GLOBAL_CLEAR, vfe->base + VFE_0_IRQ_CMD);
 }
 
-/*
- * vfe_pm_domain_off - Disable power domains specific to this VFE.
- * @vfe: VFE Device
- */
-static void vfe_pm_domain_off(struct vfe_device *vfe)
-{
-	if (!vfe)
-		return;
-
-	device_link_del(vfe->genpd_link);
-}
-
-/*
- * vfe_pm_domain_on - Enable power domains specific to this VFE.
- * @vfe: VFE Device
- */
-static int vfe_pm_domain_on(struct vfe_device *vfe)
-{
-	struct camss *camss = vfe->camss;
-	enum vfe_line_id id = vfe->id;
-
-	vfe->genpd_link = device_link_add(camss->dev, vfe->genpd, DL_FLAG_STATELESS |
-					  DL_FLAG_PM_RUNTIME | DL_FLAG_RPM_ACTIVE);
-
-	if (!vfe->genpd_link) {
-		dev_err(vfe->camss->dev, "Failed to add VFE#%d to power domain\n", id);
-		return -EINVAL;
-	}
-
-	return 0;
-}
-
 static void vfe_violation_read(struct vfe_device *vfe)
 {
 	u32 violation = readl_relaxed(vfe->base + VFE_0_VIOLATION_STATUS);
diff --git a/drivers/media/platform/qcom/camss/camss-vfe-4-8.c b/drivers/media/platform/qcom/camss/camss-vfe-4-8.c
index 5bd5b6b3c992a..f52fa30f3853e 100644
--- a/drivers/media/platform/qcom/camss/camss-vfe-4-8.c
+++ b/drivers/media/platform/qcom/camss/camss-vfe-4-8.c
@@ -1093,35 +1093,6 @@ static void vfe_isr_read(struct vfe_device *vfe, u32 *value0, u32 *value1)
 	writel_relaxed(VFE_0_IRQ_CMD_GLOBAL_CLEAR, vfe->base + VFE_0_IRQ_CMD);
 }
 
-/*
- * vfe_pm_domain_off - Disable power domains specific to this VFE.
- * @vfe: VFE Device
- */
-static void vfe_pm_domain_off(struct vfe_device *vfe)
-{
-	device_link_del(vfe->genpd_link);
-}
-
-/*
- * vfe_pm_domain_on - Enable power domains specific to this VFE.
- * @vfe: VFE Device
- */
-static int vfe_pm_domain_on(struct vfe_device *vfe)
-{
-	struct camss *camss = vfe->camss;
-	enum vfe_line_id id = vfe->id;
-
-	vfe->genpd_link = device_link_add(camss->dev, vfe->genpd, DL_FLAG_STATELESS |
-					  DL_FLAG_PM_RUNTIME | DL_FLAG_RPM_ACTIVE);
-
-	if (!vfe->genpd_link) {
-		dev_err(vfe->camss->dev, "Failed to add VFE#%d to power domain\n", id);
-		return -EINVAL;
-	}
-
-	return 0;
-}
-
 static void vfe_violation_read(struct vfe_device *vfe)
 {
 	u32 violation = readl_relaxed(vfe->base + VFE_0_VIOLATION_STATUS);
diff --git a/drivers/media/platform/qcom/camss/camss-vfe-480.c b/drivers/media/platform/qcom/camss/camss-vfe-480.c
index ca16a7ebb2903..4652e8b4cff58 100644
--- a/drivers/media/platform/qcom/camss/camss-vfe-480.c
+++ b/drivers/media/platform/qcom/camss/camss-vfe-480.c
@@ -452,42 +452,6 @@ static void vfe_isr_wm_done(struct vfe_device *vfe, u8 wm)
 	spin_unlock_irqrestore(&vfe->output_lock, flags);
 }
 
-/*
- * vfe_pm_domain_off - Disable power domains specific to this VFE.
- * @vfe: VFE Device
- */
-static void vfe_pm_domain_off(struct vfe_device *vfe)
-{
-	struct camss *camss = vfe->camss;
-
-	if (vfe->id >= camss->res->vfe_num)
-		return;
-
-	device_link_del(vfe->genpd_link);
-}
-
-/*
- * vfe_pm_domain_on - Enable power domains specific to this VFE.
- * @vfe: VFE Device
- */
-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->res->vfe_num)
-		return 0;
-
-	vfe->genpd_link = device_link_add(camss->dev, vfe->genpd,
-					  DL_FLAG_STATELESS |
-					  DL_FLAG_PM_RUNTIME |
-					  DL_FLAG_RPM_ACTIVE);
-	if (!vfe->genpd_link)
-		return -EINVAL;
-
-	return 0;
-}
-
 /*
  * vfe_queue_buffer - Add empty buffer
  * @vid: Video device structure
diff --git a/drivers/media/platform/qcom/camss/camss-vfe.c b/drivers/media/platform/qcom/camss/camss-vfe.c
index 3d31f4289b724..fc3733baa668d 100644
--- a/drivers/media/platform/qcom/camss/camss-vfe.c
+++ b/drivers/media/platform/qcom/camss/camss-vfe.c
@@ -474,6 +474,40 @@ void vfe_isr_reset_ack(struct vfe_device *vfe)
 	complete(&vfe->reset_complete);
 }
 
+/*
+ * vfe_pm_domain_off - Disable power domains specific to this VFE.
+ * @vfe: VFE Device
+ */
+void vfe_pm_domain_off(struct vfe_device *vfe)
+{
+	if (!vfe->genpd)
+		return;
+
+	device_link_del(vfe->genpd_link);
+}
+
+/*
+ * vfe_pm_domain_on - Enable power domains specific to this VFE.
+ * @vfe: VFE Device
+ */
+int vfe_pm_domain_on(struct vfe_device *vfe)
+{
+	struct camss *camss = vfe->camss;
+	enum vfe_line_id id = vfe->id;
+
+	if (!vfe->genpd)
+		return 0;
+
+	vfe->genpd_link = device_link_add(camss->dev, vfe->genpd,
+					  DL_FLAG_STATELESS |
+					  DL_FLAG_PM_RUNTIME |
+					  DL_FLAG_RPM_ACTIVE);
+	if (!vfe->genpd_link)
+		return -EINVAL;
+
+	return 0;
+}
+
 static int vfe_match_clock_names(struct vfe_device *vfe,
 				 struct camss_clock *clock)
 {
diff --git a/drivers/media/platform/qcom/camss/camss-vfe.h b/drivers/media/platform/qcom/camss/camss-vfe.h
index c1c50023d4876..992a2103ec44c 100644
--- a/drivers/media/platform/qcom/camss/camss-vfe.h
+++ b/drivers/media/platform/qcom/camss/camss-vfe.h
@@ -203,6 +203,18 @@ int vfe_reset(struct vfe_device *vfe);
  */
 int vfe_disable(struct vfe_line *line);
 
+/*
+ * vfe_pm_domain_off - Disable power domains specific to this VFE.
+ * @vfe: VFE Device
+ */
+void vfe_pm_domain_off(struct vfe_device *vfe);
+
+/*
+ * vfe_pm_domain_on - Enable power domains specific to this VFE.
+ * @vfe: VFE Device
+ */
+int vfe_pm_domain_on(struct vfe_device *vfe);
+
 extern const struct vfe_hw_ops vfe_ops_4_1;
 extern const struct vfe_hw_ops vfe_ops_4_7;
 extern const struct vfe_hw_ops vfe_ops_4_8;
-- 
2.42.0

Re: [PATCH 2/4] media: qcom: camss: Use common VFE pm_domain_on/pm_domain_off where applicable

[Konrad Dybcio]

On 10/25/23 00:42, Bryan O'Donoghue wrote:
> For the various versions of VFE we have a boiler-plate
> pm_domain_on/pm_domain_off callback pair of the general form.
> 
> - Error check.
>    Not always done but applicable to all.
> 
> - device_link_add (DL_FLAG_STATELESS | DL_FLAG_PM_RUNTIME |
>                     DL_FLAG_RPM_ACTIVE);
> 
> - Error check returning -EINVAL on error.
> 
> - Return 0
> 
> Reduce the pattern down to a common callback. VFE 4.1 is a special case
> which to me also indicates that it is worthwhile maintaining an indirection
> for the vfe_pm_domain_{on|off} for now.
Are there issues when powering it off like all the others?

> 
> Otherwise lets chuck out a bunch of needlessly replicated code.
> 
> Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
> ---
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>

Konrad

Re: [PATCH 2/4] media: qcom: camss: Use common VFE pm_domain_on/pm_domain_off where applicable

[Bryan O'Donoghue]

On 25/10/2023 10:18, Konrad Dybcio wrote:
>> educe the pattern down to a common callback. VFE 4.1 is a special case
>> which to me also indicates that it is worthwhile maintaining an 
>> indirection
>> for the vfe_pm_domain_{on|off} for now.
> Are there issues when powering it off like all the others?

4.1 doesn't have a VFE power-domain just a top level controller PD, 
however I think a blank callback is neater than

if (vfe->pm_domain_on) {
     vfe->pd_domain_on();
}

its just vfe->pm_domain_on(); at the cost of 1 or 2 instructions for 
indirection.

---
bod

Re: [PATCH 2/4] media: qcom: camss: Use common VFE pm_domain_on/pm_domain_off where applicable

[Konrad Dybcio]

On 10/25/23 12:40, Bryan O'Donoghue wrote:
> On 25/10/2023 10:18, Konrad Dybcio wrote:
>>> educe the pattern down to a common callback. VFE 4.1 is a special case
>>> which to me also indicates that it is worthwhile maintaining an indirection
>>> for the vfe_pm_domain_{on|off} for now.
>> Are there issues when powering it off like all the others?
> 
> 4.1 doesn't have a VFE power-domain just a top level controller PD, however I think a blank callback is neater than
> 
> if (vfe->pm_domain_on) {
>      vfe->pd_domain_on();
> }
> 
> its just vfe->pm_domain_on(); at the cost of 1 or 2 instructions for indirection.
Right

Konrad

[PATCH 3/4] media: qcom: camss: Move VFE power-domain specifics into vfe.c

[Bryan O'Donoghue]

Moving the location of the hooks to VFE power domains has several
advantages.

1. Separation of concerns and functional decomposition.
   vfe.c should be responsible for and know best how manage
   power-domains for a VFE, excising from camss.c follows this
   principle.

2. Embeddeding a pointer to genpd in struct camss_vfe{} meas that we can
   dispense with a bunch of kmalloc array inside of camss.c.

3. Splitting up titan top gdsc from vfe/ife gdsc provides a base for
   breaking up magic indexes in dtsi.

Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
---
 drivers/media/platform/qcom/camss/camss-vfe.c | 24 ++++++-
 drivers/media/platform/qcom/camss/camss-vfe.h |  2 +
 drivers/media/platform/qcom/camss/camss.c     | 63 +++++++++----------
 drivers/media/platform/qcom/camss/camss.h     |  4 +-
 4 files changed, 55 insertions(+), 38 deletions(-)

diff --git a/drivers/media/platform/qcom/camss/camss-vfe.c b/drivers/media/platform/qcom/camss/camss-vfe.c
index fc3733baa668d..bc14ae4771e31 100644
--- a/drivers/media/platform/qcom/camss/camss-vfe.c
+++ b/drivers/media/platform/qcom/camss/camss-vfe.c
@@ -14,6 +14,7 @@
 #include <linux/mutex.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
+#include <linux/pm_domain.h>
 #include <linux/pm_runtime.h>
 #include <linux/spinlock_types.h>
 #include <linux/spinlock.h>
@@ -493,7 +494,6 @@ void vfe_pm_domain_off(struct vfe_device *vfe)
 int vfe_pm_domain_on(struct vfe_device *vfe)
 {
 	struct camss *camss = vfe->camss;
-	enum vfe_line_id id = vfe->id;
 
 	if (!vfe->genpd)
 		return 0;
@@ -1381,8 +1381,13 @@ int msm_vfe_subdev_init(struct camss *camss, struct vfe_device *vfe,
 	if (!res->line_num)
 		return -EINVAL;
 
-	if (camss->genpd)
-		vfe->genpd = camss->genpd[id];
+	if (camss->genpd) {
+		vfe->genpd = dev_pm_domain_attach_by_id(camss->dev, id);
+		if (IS_ERR(vfe->genpd)) {
+			ret = PTR_ERR(vfe->genpd);
+			return ret;
+		}
+	}
 
 	vfe->line_num = res->line_num;
 	vfe->ops->subdev_init(dev, vfe);
@@ -1506,6 +1511,19 @@ int msm_vfe_subdev_init(struct camss *camss, struct vfe_device *vfe,
 	return 0;
 }
 
+/*
+ * msm_vfe_genpd_cleanup - Cleanup VFE genpd linkages
+ * @vfe: VFE device
+ *
+ */
+void msm_vfe_genpd_cleanup(struct vfe_device *vfe)
+{
+	if (vfe->genpd_link)
+		device_link_del(vfe->genpd_link);
+
+	dev_pm_domain_detach(vfe->genpd, true);
+}
+
 /*
  * vfe_link_setup - Setup VFE connections
  * @entity: Pointer to media entity structure
diff --git a/drivers/media/platform/qcom/camss/camss-vfe.h b/drivers/media/platform/qcom/camss/camss-vfe.h
index 992a2103ec44c..cdbe59d8d437e 100644
--- a/drivers/media/platform/qcom/camss/camss-vfe.h
+++ b/drivers/media/platform/qcom/camss/camss-vfe.h
@@ -159,6 +159,8 @@ struct camss_subdev_resources;
 int msm_vfe_subdev_init(struct camss *camss, struct vfe_device *vfe,
 			const struct camss_subdev_resources *res, u8 id);
 
+void msm_vfe_genpd_cleanup(struct vfe_device *vfe);
+
 int msm_vfe_register_entities(struct vfe_device *vfe,
 			      struct v4l2_device *v4l2_dev);
 
diff --git a/drivers/media/platform/qcom/camss/camss.c b/drivers/media/platform/qcom/camss/camss.c
index 8e78dd8d5961e..523b36d86f6cf 100644
--- a/drivers/media/platform/qcom/camss/camss.c
+++ b/drivers/media/platform/qcom/camss/camss.c
@@ -1479,7 +1479,6 @@ static const struct media_device_ops camss_media_ops = {
 static int camss_configure_pd(struct camss *camss)
 {
 	struct device *dev = camss->dev;
-	int i;
 	int ret;
 
 	camss->genpd_num = of_count_phandle_with_args(dev->of_node,
@@ -1498,45 +1497,36 @@ static int camss_configure_pd(struct camss *camss)
 	if (camss->genpd_num == 1)
 		return 0;
 
-	camss->genpd = devm_kmalloc_array(dev, camss->genpd_num,
-					  sizeof(*camss->genpd), GFP_KERNEL);
-	if (!camss->genpd)
-		return -ENOMEM;
-
-	camss->genpd_link = devm_kmalloc_array(dev, camss->genpd_num,
-					       sizeof(*camss->genpd_link),
-					       GFP_KERNEL);
-	if (!camss->genpd_link)
-		return -ENOMEM;
+	/*
+	 * If the number of power-domains is greather than the number of VFEs
+	 * then the additional power-domain is for the entire CAMSS block the
+	 * 'top' power-domain.
+	 */
+	if (camss->genpd_num <= camss->res->vfe_num)
+		return 0;
 
 	/*
 	 * 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 = dev_pm_domain_attach_by_id(camss->dev, camss->genpd_num - 1);
+	if (IS_ERR(camss->genpd)) {
+		ret = PTR_ERR(camss->genpd);
+		goto fail_pm;
 	}
-
-	if (i > camss->res->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;
-		}
+	camss->genpd_link = device_link_add(camss->dev, camss->genpd,
+					    DL_FLAG_STATELESS | DL_FLAG_PM_RUNTIME |
+					    DL_FLAG_RPM_ACTIVE);
+	if (!camss->genpd_link) {
+		ret = -EINVAL;
+		goto fail_pm;
 	}
 
 	return 0;
 
 fail_pm:
-	for (--i ; i >= 0; i--)
-		dev_pm_domain_detach(camss->genpd[i], true);
+	dev_pm_domain_detach(camss->genpd, true);
 
 	return ret;
 }
@@ -1558,18 +1548,25 @@ static int camss_icc_get(struct camss *camss)
 	return 0;
 }
 
-static void camss_genpd_cleanup(struct camss *camss)
+static void camss_genpd_subdevice_cleanup(struct camss *camss)
 {
 	int i;
 
+	for (i = 0; i < camss->vfe_total_num; i++)
+		msm_vfe_genpd_cleanup(&camss->vfe[i]);
+}
+
+static void camss_genpd_cleanup(struct camss *camss)
+{
 	if (camss->genpd_num == 1)
 		return;
 
-	if (camss->genpd_num > camss->res->vfe_num)
-		device_link_del(camss->genpd_link[camss->genpd_num - 1]);
+	if (camss->genpd_link)
+		device_link_del(camss->genpd_link);
+
+	dev_pm_domain_detach(camss->genpd, true);
 
-	for (i = 0; i < camss->genpd_num; i++)
-		dev_pm_domain_detach(camss->genpd[i], true);
+	camss_genpd_subdevice_cleanup(camss);
 }
 
 /*
diff --git a/drivers/media/platform/qcom/camss/camss.h b/drivers/media/platform/qcom/camss/camss.h
index 8acad7321c09d..95486c494afc6 100644
--- a/drivers/media/platform/qcom/camss/camss.h
+++ b/drivers/media/platform/qcom/camss/camss.h
@@ -106,8 +106,8 @@ struct camss {
 	struct vfe_device *vfe;
 	atomic_t ref_count;
 	int genpd_num;
-	struct device **genpd;
-	struct device_link **genpd_link;
+	struct device *genpd;
+	struct device_link *genpd_link;
 	struct icc_path *icc_path[ICC_SM8250_COUNT];
 	const struct camss_resources *res;
 	unsigned int vfe_total_num;
-- 
2.42.0

[PATCH 4/4] media: qcom: camss: Add support for named power-domains

[Bryan O'Donoghue]

Right now we use fixed indexes to assign power-domains, with a
requirement for the TOP GDSC to come last in the list.

Adding support for named power-domains means the declaration in the dtsi
can come in any order.

After this change we continue to support the old indexing - if a SoC
resource declration or the in-use dtb doesn't declare power-domain names
we fall back to the default legacy indexing.

From this point on though new SoC additions should contain named
power-domains, eventually we will drop support for legacy indexing.

Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
---
 drivers/media/platform/qcom/camss/camss-vfe.c | 24 ++++++++++++++++-
 drivers/media/platform/qcom/camss/camss.c     | 26 +++++++++++++++----
 drivers/media/platform/qcom/camss/camss.h     |  2 ++
 3 files changed, 46 insertions(+), 6 deletions(-)

diff --git a/drivers/media/platform/qcom/camss/camss-vfe.c b/drivers/media/platform/qcom/camss/camss-vfe.c
index bc14ae4771e31..12c64c505befd 100644
--- a/drivers/media/platform/qcom/camss/camss-vfe.c
+++ b/drivers/media/platform/qcom/camss/camss-vfe.c
@@ -1381,7 +1381,29 @@ int msm_vfe_subdev_init(struct camss *camss, struct vfe_device *vfe,
 	if (!res->line_num)
 		return -EINVAL;
 
-	if (camss->genpd) {
+	/* Power domain */
+
+	if (res->pd_name) {
+		vfe->genpd = dev_pm_domain_attach_by_name(camss->dev,
+							  res->pd_name);
+		if (IS_ERR(vfe->genpd)) {
+			ret = PTR_ERR(vfe->genpd);
+			return ret;
+		}
+	}
+
+	if (camss->genpd && !vfe->genpd) {
+		/*
+		 * Legacy magic index.
+		 * Requires
+		 * power-domain = <VFE_X>,
+		 *                <VFE_Y>,
+		 *                <TITAN_TOP>
+		 * id must correspondng to the index of the VFE which must
+		 * come before the TOP GDSC. VFE Lite has no individually
+		 * collapasible domain which is why id < vfe_num is a valid
+		 * check.
+		 */
 		vfe->genpd = dev_pm_domain_attach_by_id(camss->dev, id);
 		if (IS_ERR(vfe->genpd)) {
 			ret = PTR_ERR(vfe->genpd);
diff --git a/drivers/media/platform/qcom/camss/camss.c b/drivers/media/platform/qcom/camss/camss.c
index 523b36d86f6cf..fb5276f4d9448 100644
--- a/drivers/media/platform/qcom/camss/camss.c
+++ b/drivers/media/platform/qcom/camss/camss.c
@@ -1506,12 +1506,28 @@ static int camss_configure_pd(struct camss *camss)
 		return 0;
 
 	/*
-	 * 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.
+	 * If a power-domain name is defined try to use it.
+	 * It is possible we are running a new kernel with an old dtb so
+	 * fallback to indexes even if a pd_name is defined but not found.
 	 */
-	camss->genpd = dev_pm_domain_attach_by_id(camss->dev, camss->genpd_num - 1);
-	if (IS_ERR(camss->genpd)) {
+	if (camss->res->pd_name) {
+		camss->genpd = dev_pm_domain_attach_by_name(camss->dev,
+							    camss->res->pd_name);
+		if (IS_ERR(camss->genpd)) {
+			ret = PTR_ERR(camss->genpd);
+			goto fail_pm;
+		}
+	}
+
+	if (!camss->genpd) {
+		/*
+		 * Legacy magic index. TITAN_TOP GDSC must be the last
+		 * item in the power-domain list.
+		 */
+		camss->genpd = dev_pm_domain_attach_by_id(camss->dev,
+							  camss->genpd_num - 1);
+	}
+	if (IS_ERR_OR_NULL(camss->genpd)) {
 		ret = PTR_ERR(camss->genpd);
 		goto fail_pm;
 	}
diff --git a/drivers/media/platform/qcom/camss/camss.h b/drivers/media/platform/qcom/camss/camss.h
index 95486c494afc6..6762ce9631476 100644
--- a/drivers/media/platform/qcom/camss/camss.h
+++ b/drivers/media/platform/qcom/camss/camss.h
@@ -48,6 +48,7 @@ struct camss_subdev_resources {
 	u32 clock_rate[CAMSS_RES_MAX][CAMSS_RES_MAX];
 	char *reg[CAMSS_RES_MAX];
 	char *interrupt[CAMSS_RES_MAX];
+	char *pd_name;
 	u8 line_num;
 	const void *ops;
 };
@@ -83,6 +84,7 @@ enum icc_count {
 
 struct camss_resources {
 	enum camss_version version;
+	const char *pd_name;
 	const struct camss_subdev_resources *csiphy_res;
 	const struct camss_subdev_resources *csid_res;
 	const struct camss_subdev_resources *ispif_res;
-- 
2.42.0