2023-01-26 18:25:01

by Rayyan Ansari

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Subject: [PATCH v4 0/2] SimpleDRM: allow configuring physical width and height

Hello,

The following patches:
- Add support for configuring the width-mm and height-mm DRM mode
properties in the SimpleDRM driver via Device Tree
- Document these two new Device Tree properties

This is useful for allowing interfaces such as Phosh to calculate
proper scaling values and for early boot code knowing if hi-dpi
rendering is necessary.

Changes since v3:
- Use panel node

Rayyan Ansari (2):
drm/simpledrm: Allow physical width and height configuration via panel
node
dt-bindings: display: simple-framebuffer: Document the panel node

.../bindings/display/simple-framebuffer.yaml | 9 ++++++
drivers/gpu/drm/tiny/simpledrm.c | 32 +++++++++++++------
2 files changed, 32 insertions(+), 9 deletions(-)

--
2.39.1



2023-01-26 18:25:05

by Rayyan Ansari

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Subject: [PATCH v4 2/2] dt-bindings: display: simple-framebuffer: Document the panel node

Document the new panel node and what it is used for.

Signed-off-by: Rayyan Ansari <[email protected]>
---
.../devicetree/bindings/display/simple-framebuffer.yaml | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/Documentation/devicetree/bindings/display/simple-framebuffer.yaml b/Documentation/devicetree/bindings/display/simple-framebuffer.yaml
index dd64f70b5014..4e10a100b6c8 100644
--- a/Documentation/devicetree/bindings/display/simple-framebuffer.yaml
+++ b/Documentation/devicetree/bindings/display/simple-framebuffer.yaml
@@ -26,6 +26,11 @@ description: |+
over control to a driver for the real hardware. The bindings for the
hw nodes must specify which node is considered the primary node.

+ If a panel node is given, then the driver uses this to configure the
+ physical width and height of the display. If no panel node is given,
+ then the driver uses the width and height properties of the simplefb
+ node to estimate it.
+
It is advised to add display# aliases to help the OS determine how
to number things. If display# aliases are used, then if the simplefb
node contains a display property then the /aliases/display# path
@@ -110,6 +115,10 @@ properties:
$ref: /schemas/types.yaml#/definitions/phandle
description: Primary display hardware node

+ panel:
+ $ref: /schemas/types.yaml#/definitions/phandle
+ description: Display panel node
+
allwinner,pipeline:
description: Pipeline used by the framebuffer on Allwinner SoCs
enum:
--
2.39.1


2023-01-26 18:25:07

by Rayyan Ansari

[permalink] [raw]
Subject: [PATCH v4 1/2] drm/simpledrm: Allow physical width and height configuration via panel node

Parse the width-mm and height-mm devicetree properties of the panel node,
and use this to set the DRM Display Mode instead of calculating it
based on a hardcoded DPI.

Signed-off-by: Rayyan Ansari <[email protected]>
---
drivers/gpu/drm/tiny/simpledrm.c | 32 +++++++++++++++++++++++---------
1 file changed, 23 insertions(+), 9 deletions(-)

diff --git a/drivers/gpu/drm/tiny/simpledrm.c b/drivers/gpu/drm/tiny/simpledrm.c
index 162eb44dcba8..f8b18441cfcb 100644
--- a/drivers/gpu/drm/tiny/simpledrm.c
+++ b/drivers/gpu/drm/tiny/simpledrm.c
@@ -599,16 +599,12 @@ static const struct drm_mode_config_funcs simpledrm_mode_config_funcs = {
*/

static struct drm_display_mode simpledrm_mode(unsigned int width,
- unsigned int height)
+ unsigned int height,
+ unsigned int width_mm,
+ unsigned int height_mm)
{
- /*
- * Assume a monitor resolution of 96 dpi to
- * get a somewhat reasonable screen size.
- */
const struct drm_display_mode mode = {
- DRM_MODE_INIT(60, width, height,
- DRM_MODE_RES_MM(width, 96ul),
- DRM_MODE_RES_MM(height, 96ul))
+ DRM_MODE_INIT(60, width, height, width_mm, height_mm)
};

return mode;
@@ -622,6 +618,8 @@ static struct simpledrm_device *simpledrm_device_create(struct drm_driver *drv,
struct simpledrm_device *sdev;
struct drm_device *dev;
int width, height, stride;
+ int width_mm = 0, height_mm = 0;
+ struct device_node *panel_node;
const struct drm_format_info *format;
struct resource *res, *mem;
void __iomem *screen_base;
@@ -676,6 +674,13 @@ static struct simpledrm_device *simpledrm_device_create(struct drm_driver *drv,
format = simplefb_get_format_of(dev, of_node);
if (IS_ERR(format))
return ERR_CAST(format);
+
+ panel_node = of_parse_phandle(of_node, "panel", 0);
+ if (panel_node) {
+ simplefb_read_u32_of(dev, panel_node, "width-mm", &width_mm);
+ simplefb_read_u32_of(dev, panel_node, "height-mm", &height_mm);
+ of_node_put(panel_node);
+ }
} else {
drm_err(dev, "no simplefb configuration found\n");
return ERR_PTR(-ENODEV);
@@ -686,7 +691,16 @@ static struct simpledrm_device *simpledrm_device_create(struct drm_driver *drv,
return ERR_PTR(-EINVAL);
}

- sdev->mode = simpledrm_mode(width, height);
+ /*
+ * Assume a monitor resolution of 96 dpi if physical dimensions
+ * are not specified to get a somewhat reasonable screen size.
+ */
+ if (!width_mm)
+ width_mm = DRM_MODE_RES_MM(width, 96ul);
+ if (!height_mm)
+ height_mm = DRM_MODE_RES_MM(height, 96ul);
+
+ sdev->mode = simpledrm_mode(width, height, width_mm, height_mm);
sdev->format = format;
sdev->pitch = stride;

--
2.39.1


2023-01-30 19:01:44

by Rob Herring (Arm)

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Subject: Re: [PATCH v4 2/2] dt-bindings: display: simple-framebuffer: Document the panel node


On Thu, 26 Jan 2023 18:24:35 +0000, Rayyan Ansari wrote:
> Document the new panel node and what it is used for.
>
> Signed-off-by: Rayyan Ansari <[email protected]>
> ---
> .../devicetree/bindings/display/simple-framebuffer.yaml | 9 +++++++++
> 1 file changed, 9 insertions(+)
>

Reviewed-by: Rob Herring <[email protected]>

2023-01-31 09:06:56

by Thomas Zimmermann

[permalink] [raw]
Subject: Re: [PATCH v4 1/2] drm/simpledrm: Allow physical width and height configuration via panel node



Am 26.01.23 um 19:24 schrieb Rayyan Ansari:
> Parse the width-mm and height-mm devicetree properties of the panel node,
> and use this to set the DRM Display Mode instead of calculating it
> based on a hardcoded DPI.
>
> Signed-off-by: Rayyan Ansari <[email protected]>

Reviewed-by: Thomas Zimmermann <[email protected]>

> ---
> drivers/gpu/drm/tiny/simpledrm.c | 32 +++++++++++++++++++++++---------
> 1 file changed, 23 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/gpu/drm/tiny/simpledrm.c b/drivers/gpu/drm/tiny/simpledrm.c
> index 162eb44dcba8..f8b18441cfcb 100644
> --- a/drivers/gpu/drm/tiny/simpledrm.c
> +++ b/drivers/gpu/drm/tiny/simpledrm.c
> @@ -599,16 +599,12 @@ static const struct drm_mode_config_funcs simpledrm_mode_config_funcs = {
> */
>
> static struct drm_display_mode simpledrm_mode(unsigned int width,
> - unsigned int height)
> + unsigned int height,
> + unsigned int width_mm,
> + unsigned int height_mm)
> {
> - /*
> - * Assume a monitor resolution of 96 dpi to
> - * get a somewhat reasonable screen size.
> - */
> const struct drm_display_mode mode = {
> - DRM_MODE_INIT(60, width, height,
> - DRM_MODE_RES_MM(width, 96ul),
> - DRM_MODE_RES_MM(height, 96ul))
> + DRM_MODE_INIT(60, width, height, width_mm, height_mm)
> };
>
> return mode;
> @@ -622,6 +618,8 @@ static struct simpledrm_device *simpledrm_device_create(struct drm_driver *drv,
> struct simpledrm_device *sdev;
> struct drm_device *dev;
> int width, height, stride;
> + int width_mm = 0, height_mm = 0;
> + struct device_node *panel_node;
> const struct drm_format_info *format;
> struct resource *res, *mem;
> void __iomem *screen_base;
> @@ -676,6 +674,13 @@ static struct simpledrm_device *simpledrm_device_create(struct drm_driver *drv,
> format = simplefb_get_format_of(dev, of_node);
> if (IS_ERR(format))
> return ERR_CAST(format);
> +
> + panel_node = of_parse_phandle(of_node, "panel", 0);
> + if (panel_node) {
> + simplefb_read_u32_of(dev, panel_node, "width-mm", &width_mm);
> + simplefb_read_u32_of(dev, panel_node, "height-mm", &height_mm);
> + of_node_put(panel_node);
> + }
> } else {
> drm_err(dev, "no simplefb configuration found\n");
> return ERR_PTR(-ENODEV);
> @@ -686,7 +691,16 @@ static struct simpledrm_device *simpledrm_device_create(struct drm_driver *drv,
> return ERR_PTR(-EINVAL);
> }
>
> - sdev->mode = simpledrm_mode(width, height);
> + /*
> + * Assume a monitor resolution of 96 dpi if physical dimensions
> + * are not specified to get a somewhat reasonable screen size.
> + */
> + if (!width_mm)
> + width_mm = DRM_MODE_RES_MM(width, 96ul);
> + if (!height_mm)
> + height_mm = DRM_MODE_RES_MM(height, 96ul);
> +
> + sdev->mode = simpledrm_mode(width, height, width_mm, height_mm);
> sdev->format = format;
> sdev->pitch = stride;
>

--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Ivo Totev


Attachments:
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2023-01-31 09:44:04

by Thomas Zimmermann

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Subject: Re: [PATCH v4 0/2] SimpleDRM: allow configuring physical width and height

Hi,

thanks a lot. I've added your patches to drm-misc-next. They should be
in Linux v6.4.

Best regards
Thomas

Am 26.01.23 um 19:24 schrieb Rayyan Ansari:
> Hello,
>
> The following patches:
> - Add support for configuring the width-mm and height-mm DRM mode
> properties in the SimpleDRM driver via Device Tree
> - Document these two new Device Tree properties
>
> This is useful for allowing interfaces such as Phosh to calculate
> proper scaling values and for early boot code knowing if hi-dpi
> rendering is necessary.
>
> Changes since v3:
> - Use panel node
>
> Rayyan Ansari (2):
> drm/simpledrm: Allow physical width and height configuration via panel
> node
> dt-bindings: display: simple-framebuffer: Document the panel node
>
> .../bindings/display/simple-framebuffer.yaml | 9 ++++++
> drivers/gpu/drm/tiny/simpledrm.c | 32 +++++++++++++------
> 2 files changed, 32 insertions(+), 9 deletions(-)
>

--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Ivo Totev


Attachments:
OpenPGP_signature (840.00 B)
OpenPGP digital signature