[1/3] drm/vc4: Remove the need for the GPU-subsystem DT node.
diff mbox

Message ID 20180409230040.1100-1-eric@anholt.net
State New
Headers show

Commit Message

Eric Anholt April 9, 2018, 11 p.m. UTC
The GPU subsystem node was a workaround to have a central device to
bind V3D and display to.  Following the lead of 246774d17fc0
("drm/etnaviv: remove the need for a gpu-subsystem DT node"), remove
the subsystem node usage and just create a platform device for the DRM
device to attach to if any of the subsystem devices are present.

Signed-off-by: Eric Anholt <eric@anholt.net>
---
 .../bindings/display/brcm,bcm-vc4.txt         |  7 ----
 drivers/gpu/drm/vc4/vc4_drv.c                 | 33 ++++++++++++++-----
 drivers/gpu/drm/vc4/vc4_hvs.c                 |  1 +
 drivers/gpu/drm/vc4/vc4_v3d.c                 |  1 +
 4 files changed, 27 insertions(+), 15 deletions(-)

Comments

Stefan Wahren April 10, 2018, 6:28 p.m. UTC | #1
Hi Eric,

> Eric Anholt <eric@anholt.net> hat am 10. April 2018 um 01:00 geschrieben:
> 
> 
> The GPU subsystem node was a workaround to have a central device to
> bind V3D and display to.  Following the lead of 246774d17fc0
> ("drm/etnaviv: remove the need for a gpu-subsystem DT node"), remove
> the subsystem node usage and just create a platform device for the DRM
> device to attach to if any of the subsystem devices are present.

i didn't test it. Does the code change keep the backward compatibility with older DT?
Eric Anholt April 10, 2018, 7:39 p.m. UTC | #2
Stefan Wahren <stefan.wahren@i2se.com> writes:

> Hi Eric,
>
>> Eric Anholt <eric@anholt.net> hat am 10. April 2018 um 01:00 geschrieben:
>> 
>> 
>> The GPU subsystem node was a workaround to have a central device to
>> bind V3D and display to.  Following the lead of 246774d17fc0
>> ("drm/etnaviv: remove the need for a gpu-subsystem DT node"), remove
>> the subsystem node usage and just create a platform device for the DRM
>> device to attach to if any of the subsystem devices are present.
>
> i didn't test it. Does the code change keep the backward compatibility with older DT?

Yes.
Rob Herring April 13, 2018, 5:56 p.m. UTC | #3
On Mon, Apr 09, 2018 at 04:00:38PM -0700, Eric Anholt wrote:
> The GPU subsystem node was a workaround to have a central device to
> bind V3D and display to.  Following the lead of 246774d17fc0
> ("drm/etnaviv: remove the need for a gpu-subsystem DT node"), remove
> the subsystem node usage and just create a platform device for the DRM
> device to attach to if any of the subsystem devices are present.
> 
> Signed-off-by: Eric Anholt <eric@anholt.net>
> ---
>  .../bindings/display/brcm,bcm-vc4.txt         |  7 ----
>  drivers/gpu/drm/vc4/vc4_drv.c                 | 33 ++++++++++++++-----
>  drivers/gpu/drm/vc4/vc4_hvs.c                 |  1 +
>  drivers/gpu/drm/vc4/vc4_v3d.c                 |  1 +
>  4 files changed, 27 insertions(+), 15 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt b/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt
> index 284e2b14cfbe..5fd4717101d6 100644
> --- a/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt
> +++ b/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt
> @@ -4,9 +4,6 @@ The VC4 device present on the Raspberry Pi includes a display system
>  with HDMI output and the HVS (Hardware Video Scaler) for compositing
>  display planes.
>  
> -Required properties for VC4:
> -- compatible:	Should be "brcm,bcm2835-vc4" or "brcm,cygnus-vc4"
> -
>  Required properties for Pixel Valve:
>  - compatible:	Should be one of "brcm,bcm2835-pixelvalve0",
>  		  "brcm,bcm2835-pixelvalve1", or "brcm,bcm2835-pixelvalve2"
> @@ -153,10 +150,6 @@ v3d: v3d@7ec00000 {
>  	interrupts = <1 10>;
>  };
>  
> -vc4: gpu {
> -	compatible = "brcm,bcm2835-vc4";
> -};
> -
>  panel: panel {
>  	compatible = "ontat,yx700wv03", "simple-panel";
>  
> diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c
> index 7c95ed5c5cac..d282ab7de03a 100644
> --- a/drivers/gpu/drm/vc4/vc4_drv.c
> +++ b/drivers/gpu/drm/vc4/vc4_drv.c
> @@ -364,22 +364,34 @@ static int vc4_platform_drm_remove(struct platform_device *pdev)
>  	return 0;
>  }
>  
> -static const struct of_device_id vc4_of_match[] = {
> -	{ .compatible = "brcm,bcm2835-vc4", },
> -	{ .compatible = "brcm,cygnus-vc4", },
> -	{},
> -};
> -MODULE_DEVICE_TABLE(of, vc4_of_match);
> -
>  static struct platform_driver vc4_platform_driver = {
>  	.probe		= vc4_platform_drm_probe,
>  	.remove		= vc4_platform_drm_remove,
>  	.driver		= {
>  		.name	= "vc4-drm",
> -		.of_match_table = vc4_of_match,
>  	},
>  };
>  
> +static bool
> +driver_of_table_has_a_match(const struct platform_driver *driver)
> +{
> +	int i;
> +

> +	for (i = 0; driver->driver.of_match_table[i].compatible; i++) {
> +		const char *compat = driver->driver.of_match_table[i].compatible;
> +		struct device_node *node;
> +
> +		while ((node = of_find_compatible_node(node, NULL, compat))) {
> +			if (of_device_is_available(node)) {
> +				of_node_put(node);
> +				return true;
> +			}
> +		}
> +	}

All this can be replaced with:

node = of_find_matching_node_and_match(NULL, driver->driver.of_match_table, NULL);
if (of_device_is_available(node)) {
	of_node_put(node);
	return true;
}

> +
> +	return false;
> +}
> +

Patch
diff mbox

diff --git a/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt b/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt
index 284e2b14cfbe..5fd4717101d6 100644
--- a/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt
+++ b/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt
@@ -4,9 +4,6 @@  The VC4 device present on the Raspberry Pi includes a display system
 with HDMI output and the HVS (Hardware Video Scaler) for compositing
 display planes.
 
-Required properties for VC4:
-- compatible:	Should be "brcm,bcm2835-vc4" or "brcm,cygnus-vc4"
-
 Required properties for Pixel Valve:
 - compatible:	Should be one of "brcm,bcm2835-pixelvalve0",
 		  "brcm,bcm2835-pixelvalve1", or "brcm,bcm2835-pixelvalve2"
@@ -153,10 +150,6 @@  v3d: v3d@7ec00000 {
 	interrupts = <1 10>;
 };
 
-vc4: gpu {
-	compatible = "brcm,bcm2835-vc4";
-};
-
 panel: panel {
 	compatible = "ontat,yx700wv03", "simple-panel";
 
diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c
index 7c95ed5c5cac..d282ab7de03a 100644
--- a/drivers/gpu/drm/vc4/vc4_drv.c
+++ b/drivers/gpu/drm/vc4/vc4_drv.c
@@ -364,22 +364,34 @@  static int vc4_platform_drm_remove(struct platform_device *pdev)
 	return 0;
 }
 
-static const struct of_device_id vc4_of_match[] = {
-	{ .compatible = "brcm,bcm2835-vc4", },
-	{ .compatible = "brcm,cygnus-vc4", },
-	{},
-};
-MODULE_DEVICE_TABLE(of, vc4_of_match);
-
 static struct platform_driver vc4_platform_driver = {
 	.probe		= vc4_platform_drm_probe,
 	.remove		= vc4_platform_drm_remove,
 	.driver		= {
 		.name	= "vc4-drm",
-		.of_match_table = vc4_of_match,
 	},
 };
 
+static bool
+driver_of_table_has_a_match(const struct platform_driver *driver)
+{
+	int i;
+
+	for (i = 0; driver->driver.of_match_table[i].compatible; i++) {
+		const char *compat = driver->driver.of_match_table[i].compatible;
+		struct device_node *node;
+
+		while ((node = of_find_compatible_node(node, NULL, compat))) {
+			if (of_device_is_available(node)) {
+				of_node_put(node);
+				return true;
+			}
+		}
+	}
+
+	return false;
+}
+
 static int __init vc4_drm_register(void)
 {
 	int ret;
@@ -389,6 +401,11 @@  static int __init vc4_drm_register(void)
 	if (ret)
 		return ret;
 
+	if (driver_of_table_has_a_match(&vc4_v3d_driver) ||
+	    driver_of_table_has_a_match(&vc4_hvs_driver)) {
+		platform_device_register_simple("vc4-drm", -1, NULL, 0);
+	}
+
 	return platform_driver_register(&vc4_platform_driver);
 }
 
diff --git a/drivers/gpu/drm/vc4/vc4_hvs.c b/drivers/gpu/drm/vc4/vc4_hvs.c
index 2b62fc5b8d85..730813ee74ae 100644
--- a/drivers/gpu/drm/vc4/vc4_hvs.c
+++ b/drivers/gpu/drm/vc4/vc4_hvs.c
@@ -262,6 +262,7 @@  static const struct of_device_id vc4_hvs_dt_match[] = {
 	{ .compatible = "brcm,bcm2835-hvs" },
 	{}
 };
+MODULE_DEVICE_TABLE(of, vc4_hvs_dt_match);
 
 struct platform_driver vc4_hvs_driver = {
 	.probe = vc4_hvs_dev_probe,
diff --git a/drivers/gpu/drm/vc4/vc4_v3d.c b/drivers/gpu/drm/vc4/vc4_v3d.c
index bfc2fa73d2ae..e77e9ebbab4b 100644
--- a/drivers/gpu/drm/vc4/vc4_v3d.c
+++ b/drivers/gpu/drm/vc4/vc4_v3d.c
@@ -459,6 +459,7 @@  static const struct of_device_id vc4_v3d_dt_match[] = {
 	{ .compatible = "brcm,vc4-v3d" },
 	{}
 };
+MODULE_DEVICE_TABLE(of, vc4_v3d_dt_match);
 
 struct platform_driver vc4_v3d_driver = {
 	.probe = vc4_v3d_dev_probe,