[PATCH v2 0/4] drm: Provide a simple encoder

[PATCH v2 0/4] drm: Provide a simple encoder

[Thomas Zimmermann]

Many DRM drivers implement an encoder with an empty implementation. This
patchset adds drm_simple_encoder_init() and drm_simple_encoder_create(),
which can be used by drivers instead. Except for the destroy callback, the
simple encoder's implementation is empty.

The patchset also converts 4 encoder instances to use the simple-encoder
helpers. But there are at least 11 other drivers which can use the helper
and I think I did not examine all drivers yet.

The patchset was smoke-tested on mgag200 by running the fbdev console
and Gnome on X11.

v2:
	* move simple encoder to KMS helpers (Daniel)
	* remove name argument; simplifies implementation (Gerd)
	* don't allocate with devm_ interfaces; unsafe with DRM (Noralf)

Thomas Zimmermann (4):
  drm/simple-kms: Add drm_simple_encoder_{init,create}()
  drm/ast: Use simple encoder
  drm/mgag200: Use simple encoder
  drm/qxl: Use simple encoder

 drivers/gpu/drm/ast/ast_drv.h           |  6 +-
 drivers/gpu/drm/ast/ast_mode.c          | 25 +++-----
 drivers/gpu/drm/drm_simple_kms_helper.c | 83 ++++++++++++++++++++++++-
 drivers/gpu/drm/mgag200/mgag200_drv.h   |  7 ---
 drivers/gpu/drm/mgag200/mgag200_mode.c  | 61 +-----------------
 drivers/gpu/drm/qxl/qxl_display.c       | 18 +-----
 include/drm/drm_simple_kms_helper.h     |  7 +++
 7 files changed, 102 insertions(+), 105 deletions(-)

--
2.25.0

[PATCH v2 1/4] drm/simple-kms: Add drm_simple_encoder_{init, create}()

[Thomas Zimmermann]

This patch makes the internal encoder implementation of the simple
KMS helpers available to drivers.

These simple-encoder helpers initialize an encoder with an empty
implementation. This covers the requirements of most of the existing
DRM drivers. A call to drm_simple_encoder_create() allocates and
initializes an encoder instance, a call to drm_simple_encoder_init()
initializes a pre-allocated instance.

v2:
	* move simple encoder to KMS helpers
	* remove name argument; simplifies implementation
	* don't allocate with devm_ interfaces; unsafe with DRM

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/gpu/drm/drm_simple_kms_helper.c | 83 ++++++++++++++++++++++++-
 include/drm/drm_simple_kms_helper.h     |  7 +++
 2 files changed, 87 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/drm_simple_kms_helper.c b/drivers/gpu/drm/drm_simple_kms_helper.c
index 15fb516ae2d8..745c2f34c42b 100644
--- a/drivers/gpu/drm/drm_simple_kms_helper.c
+++ b/drivers/gpu/drm/drm_simple_kms_helper.c
@@ -26,12 +26,90 @@
  * entity. Some flexibility for code reuse is provided through a separately
  * allocated &drm_connector object and supporting optional &drm_bridge
  * encoder drivers.
+ *
+ * Many drivers use an encoder with an empty implementation. Such encoders
+ * fulfill the minimum requirements of the display pipeline, but don't add
+ * additional functionality. The simple-encoder functions
+ * drm_simple_encoder_init() and drm_simple_encoder_create() provide an
+ * appropriate implementation.
  */
 
-static const struct drm_encoder_funcs drm_simple_kms_encoder_funcs = {
+static const struct drm_encoder_funcs drm_simple_encoder_funcs_cleanup = {
 	.destroy = drm_encoder_cleanup,
 };
 
+/**
+ * drm_simple_encoder_init - Initialize a preallocated encoder
+ * @dev: drm device
+ * @funcs: callbacks for this encoder
+ * @encoder_type: user visible type of the encoder
+ *
+ * Initialises a preallocated encoder that has no further functionality. The
+ * encoder will be released automatically. Settings for possible CRTC and
+ * clones are left to their initial values. The encoder will be cleaned up
+ * automatically as part of the mode-setting cleanup.
+ *
+ * Also see drm_simple_encoder_create().
+ *
+ * Returns:
+ * Zero on success, error code on failure.
+ */
+int drm_simple_encoder_init(struct drm_device *dev,
+			    struct drm_encoder *encoder,
+			    int encoder_type)
+{
+	return drm_encoder_init(dev, encoder,
+				&drm_simple_encoder_funcs_cleanup,
+				encoder_type, NULL);
+}
+EXPORT_SYMBOL(drm_simple_encoder_init);
+
+static void drm_encoder_destroy(struct drm_encoder *encoder)
+{
+	drm_encoder_cleanup(encoder);
+	kfree(encoder);
+}
+
+static const struct drm_encoder_funcs drm_simple_encoder_funcs_destroy = {
+	.destroy = drm_encoder_destroy,
+};
+
+/**
+ * drm_simple_encoder_create - Allocate and initialize an encoder
+ * @dev: drm device
+ * @encoder_type: user visible type of the encoder
+ *
+ * Allocates and initialises an encoder that has no further functionality. The
+ * encoder will be destroyed automatically as part of the mode-setting cleanup.
+ *
+ * See drm_simple_encoder_init() for more information.
+ *
+ * Returns:
+ * The encoder on success, a pointer-encoder error code on failure.
+ */
+struct drm_encoder *drm_simple_encoder_create(struct drm_device *dev,
+					      int encoder_type)
+{
+	struct drm_encoder *encoder;
+	int ret;
+
+	encoder = kzalloc(sizeof(*encoder), GFP_KERNEL);
+	if (!encoder)
+		return ERR_PTR(-ENOMEM);
+	ret = drm_encoder_init(dev, encoder,
+			       &drm_simple_encoder_funcs_destroy,
+			       encoder_type, NULL);
+	if (ret)
+		goto err_kfree;
+
+	return encoder;
+
+err_kfree:
+	kfree(encoder);
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL(drm_simple_encoder_create);
+
 static enum drm_mode_status
 drm_simple_kms_crtc_mode_valid(struct drm_crtc *crtc,
 			       const struct drm_display_mode *mode)
@@ -288,8 +366,7 @@ int drm_simple_display_pipe_init(struct drm_device *dev,
 		return ret;
 
 	encoder->possible_crtcs = drm_crtc_mask(crtc);
-	ret = drm_encoder_init(dev, encoder, &drm_simple_kms_encoder_funcs,
-			       DRM_MODE_ENCODER_NONE, NULL);
+	ret = drm_simple_encoder_init(dev, encoder, DRM_MODE_ENCODER_NONE);
 	if (ret || !connector)
 		return ret;
 
diff --git a/include/drm/drm_simple_kms_helper.h b/include/drm/drm_simple_kms_helper.h
index e253ba7bea9d..54d5066d90c7 100644
--- a/include/drm/drm_simple_kms_helper.h
+++ b/include/drm/drm_simple_kms_helper.h
@@ -181,4 +181,11 @@ int drm_simple_display_pipe_init(struct drm_device *dev,
 			const uint64_t *format_modifiers,
 			struct drm_connector *connector);
 
+int drm_simple_encoder_init(struct drm_device *dev,
+			    struct drm_encoder *encoder,
+			    int encoder_type);
+
+struct drm_encoder *drm_simple_encoder_create(struct drm_device *dev,
+					      int encoder_type);
+
 #endif /* __LINUX_DRM_SIMPLE_KMS_HELPER_H */
-- 
2.25.0

Re: [PATCH v2 1/4] drm/simple-kms: Add drm_simple_encoder_{init, create}()

[Sam Ravnborg]

Hi Thomas.

On Tue, Feb 18, 2020 at 09:48:12AM +0100, Thomas Zimmermann wrote:
> This patch makes the internal encoder implementation of the simple
> KMS helpers available to drivers.
> 
> These simple-encoder helpers initialize an encoder with an empty
> implementation. This covers the requirements of most of the existing
> DRM drivers. A call to drm_simple_encoder_create() allocates and
> initializes an encoder instance, a call to drm_simple_encoder_init()
> initializes a pre-allocated instance.
> 
> v2:
> 	* move simple encoder to KMS helpers
> 	* remove name argument; simplifies implementation
> 	* don't allocate with devm_ interfaces; unsafe with DRM
> 
> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
> ---
>  drivers/gpu/drm/drm_simple_kms_helper.c | 83 ++++++++++++++++++++++++-
>  include/drm/drm_simple_kms_helper.h     |  7 +++
>  2 files changed, 87 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_simple_kms_helper.c b/drivers/gpu/drm/drm_simple_kms_helper.c
> index 15fb516ae2d8..745c2f34c42b 100644
> --- a/drivers/gpu/drm/drm_simple_kms_helper.c
> +++ b/drivers/gpu/drm/drm_simple_kms_helper.c
> @@ -26,12 +26,90 @@
>   * entity. Some flexibility for code reuse is provided through a separately
>   * allocated &drm_connector object and supporting optional &drm_bridge
>   * encoder drivers.
> + *
> + * Many drivers use an encoder with an empty implementation. Such encoders
> + * fulfill the minimum requirements of the display pipeline, but don't add
> + * additional functionality. The simple-encoder functions
> + * drm_simple_encoder_init() and drm_simple_encoder_create() provide an
> + * appropriate implementation.
This paragraph reads a bit strange to me - I read this as a
justification for addding a generic encoded that can be used by exisitg
drivers.

How about something like this:

Many drivers requires a very simple encoder that only fullfill
the minimum requirements of the display pipeline and do not add
any extra functionslity.
The simple-encoder functions drm_simple_encoder_init() and
drm_simple_encoder_create() provides an impålmentation of such
a simple encoder.
The simple encoder includes automatically release of resources.

And then leave it to the changelog to tell what should be done in
existing drivers.



>   */
>  
> -static const struct drm_encoder_funcs drm_simple_kms_encoder_funcs = {
> +static const struct drm_encoder_funcs drm_simple_encoder_funcs_cleanup = {
>  	.destroy = drm_encoder_cleanup,
>  };
>  
> +/**
> + * drm_simple_encoder_init - Initialize a preallocated encoder
> + * @dev: drm device
> + * @funcs: callbacks for this encoder
> + * @encoder_type: user visible type of the encoder
> + *
> + * Initialises a preallocated encoder that has no further functionality. The
> + * encoder will be released automatically. Settings for possible CRTC and
> + * clones are left to their initial values. The encoder will be cleaned up
> + * automatically as part of the mode-setting cleanup.
> + *
> + * Also see drm_simple_encoder_create().
s/Also see/See also/??


> + *
> + * Returns:
> + * Zero on success, error code on failure.
> + */
> +int drm_simple_encoder_init(struct drm_device *dev,
> +			    struct drm_encoder *encoder,
> +			    int encoder_type)
> +{
> +	return drm_encoder_init(dev, encoder,
> +				&drm_simple_encoder_funcs_cleanup,
> +				encoder_type, NULL);
> +}
> +EXPORT_SYMBOL(drm_simple_encoder_init);
> +
> +static void drm_encoder_destroy(struct drm_encoder *encoder)
> +{
> +	drm_encoder_cleanup(encoder);
> +	kfree(encoder);
> +}
> +
> +static const struct drm_encoder_funcs drm_simple_encoder_funcs_destroy = {
> +	.destroy = drm_encoder_destroy,
> +};
> +
> +/**
> + * drm_simple_encoder_create - Allocate and initialize an encoder
> + * @dev: drm device
> + * @encoder_type: user visible type of the encoder
> + *
> + * Allocates and initialises an encoder that has no further functionality. The
> + * encoder will be destroyed automatically as part of the mode-setting cleanup.
> + *
> + * See drm_simple_encoder_init() for more information.
> + *
> + * Returns:
> + * The encoder on success, a pointer-encoder error code on failure.
                                pointer-encoded?



> + */
> +struct drm_encoder *drm_simple_encoder_create(struct drm_device *dev,
> +					      int encoder_type)
> +{
> +	struct drm_encoder *encoder;
> +	int ret;
> +
> +	encoder = kzalloc(sizeof(*encoder), GFP_KERNEL);
> +	if (!encoder)
> +		return ERR_PTR(-ENOMEM);
> +	ret = drm_encoder_init(dev, encoder,
> +			       &drm_simple_encoder_funcs_destroy,
> +			       encoder_type, NULL);
> +	if (ret)
> +		goto err_kfree;
> +
> +	return encoder;
> +
> +err_kfree:
> +	kfree(encoder);
> +	return ERR_PTR(ret);
> +}
> +EXPORT_SYMBOL(drm_simple_encoder_create);
> +
>  static enum drm_mode_status
>  drm_simple_kms_crtc_mode_valid(struct drm_crtc *crtc,
>  			       const struct drm_display_mode *mode)
> @@ -288,8 +366,7 @@ int drm_simple_display_pipe_init(struct drm_device *dev,
>  		return ret;
>  
>  	encoder->possible_crtcs = drm_crtc_mask(crtc);
> -	ret = drm_encoder_init(dev, encoder, &drm_simple_kms_encoder_funcs,
> -			       DRM_MODE_ENCODER_NONE, NULL);
> +	ret = drm_simple_encoder_init(dev, encoder, DRM_MODE_ENCODER_NONE);
>  	if (ret || !connector)
>  		return ret;
>  
> diff --git a/include/drm/drm_simple_kms_helper.h b/include/drm/drm_simple_kms_helper.h
> index e253ba7bea9d..54d5066d90c7 100644
> --- a/include/drm/drm_simple_kms_helper.h
> +++ b/include/drm/drm_simple_kms_helper.h
> @@ -181,4 +181,11 @@ int drm_simple_display_pipe_init(struct drm_device *dev,
>  			const uint64_t *format_modifiers,
>  			struct drm_connector *connector);
>  
> +int drm_simple_encoder_init(struct drm_device *dev,
> +			    struct drm_encoder *encoder,
> +			    int encoder_type);
> +
> +struct drm_encoder *drm_simple_encoder_create(struct drm_device *dev,
> +					      int encoder_type);
> +
>  #endif /* __LINUX_DRM_SIMPLE_KMS_HELPER_H */

	Sam

Re: [PATCH v2 1/4] drm/simple-kms: Add drm_simple_encoder_{init, create}()

[Sam Ravnborg]

Hi Thomas.

On Tue, Feb 18, 2020 at 09:48:12AM +0100, Thomas Zimmermann wrote:
> This patch makes the internal encoder implementation of the simple
> KMS helpers available to drivers.
> 
> These simple-encoder helpers initialize an encoder with an empty
> implementation. This covers the requirements of most of the existing
> DRM drivers. A call to drm_simple_encoder_create() allocates and
> initializes an encoder instance, a call to drm_simple_encoder_init()
> initializes a pre-allocated instance.
> 
> v2:
> 	* move simple encoder to KMS helpers
> 	* remove name argument; simplifies implementation
> 	* don't allocate with devm_ interfaces; unsafe with DRM
> 
> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
> ---
>  drivers/gpu/drm/drm_simple_kms_helper.c | 83 ++++++++++++++++++++++++-
>  include/drm/drm_simple_kms_helper.h     |  7 +++
>  2 files changed, 87 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_simple_kms_helper.c b/drivers/gpu/drm/drm_simple_kms_helper.c
> index 15fb516ae2d8..745c2f34c42b 100644
> --- a/drivers/gpu/drm/drm_simple_kms_helper.c
> +++ b/drivers/gpu/drm/drm_simple_kms_helper.c
> @@ -26,12 +26,90 @@
>   * entity. Some flexibility for code reuse is provided through a separately
>   * allocated &drm_connector object and supporting optional &drm_bridge
>   * encoder drivers.
> + *
> + * Many drivers use an encoder with an empty implementation. Such encoders
> + * fulfill the minimum requirements of the display pipeline, but don't add
> + * additional functionality. The simple-encoder functions
> + * drm_simple_encoder_init() and drm_simple_encoder_create() provide an
> + * appropriate implementation.
>   */
>  
> -static const struct drm_encoder_funcs drm_simple_kms_encoder_funcs = {
> +static const struct drm_encoder_funcs drm_simple_encoder_funcs_cleanup = {
>  	.destroy = drm_encoder_cleanup,
>  };
>  
> +/**
> + * drm_simple_encoder_init - Initialize a preallocated encoder
> + * @dev: drm device
> + * @funcs: callbacks for this encoder
> + * @encoder_type: user visible type of the encoder
> + *
> + * Initialises a preallocated encoder that has no further functionality. The
> + * encoder will be released automatically.
I got confused here. The comment says the encoder is automatically
released. But in this case we have a preallocated encoder (maybe
embedded in ast_private or something.
So the encoder is - as I understnad it - not released. But it is cleaned
up as it is also documented in the next sentences.

Sorry if I am dense, just returned from some travelling...

	Sam


Settings for possible CRTC and
> + * clones are left to their initial values. The encoder will be cleaned up
> + * automatically as part of the mode-setting cleanup.
> + *
> + * Also see drm_simple_encoder_create().
> + *
> + * Returns:
> + * Zero on success, error code on failure.
> + */
> +int drm_simple_encoder_init(struct drm_device *dev,
> +			    struct drm_encoder *encoder,
> +			    int encoder_type)
> +{
> +	return drm_encoder_init(dev, encoder,
> +				&drm_simple_encoder_funcs_cleanup,
> +				encoder_type, NULL);
> +}
> +EXPORT_SYMBOL(drm_simple_encoder_init);
> +
> +static void drm_encoder_destroy(struct drm_encoder *encoder)
> +{
> +	drm_encoder_cleanup(encoder);
> +	kfree(encoder);
> +}
> +
> +static const struct drm_encoder_funcs drm_simple_encoder_funcs_destroy = {
> +	.destroy = drm_encoder_destroy,
> +};
> +
> +/**
> + * drm_simple_encoder_create - Allocate and initialize an encoder
> + * @dev: drm device
> + * @encoder_type: user visible type of the encoder
> + *
> + * Allocates and initialises an encoder that has no further functionality. The
> + * encoder will be destroyed automatically as part of the mode-setting cleanup.
> + *
> + * See drm_simple_encoder_init() for more information.
> + *
> + * Returns:
> + * The encoder on success, a pointer-encoder error code on failure.
> + */
> +struct drm_encoder *drm_simple_encoder_create(struct drm_device *dev,
> +					      int encoder_type)
> +{
> +	struct drm_encoder *encoder;
> +	int ret;
> +
> +	encoder = kzalloc(sizeof(*encoder), GFP_KERNEL);
> +	if (!encoder)
> +		return ERR_PTR(-ENOMEM);
> +	ret = drm_encoder_init(dev, encoder,
> +			       &drm_simple_encoder_funcs_destroy,
> +			       encoder_type, NULL);
> +	if (ret)
> +		goto err_kfree;
> +
> +	return encoder;
> +
> +err_kfree:
> +	kfree(encoder);
> +	return ERR_PTR(ret);
> +}
> +EXPORT_SYMBOL(drm_simple_encoder_create);
> +
>  static enum drm_mode_status
>  drm_simple_kms_crtc_mode_valid(struct drm_crtc *crtc,
>  			       const struct drm_display_mode *mode)
> @@ -288,8 +366,7 @@ int drm_simple_display_pipe_init(struct drm_device *dev,
>  		return ret;
>  
>  	encoder->possible_crtcs = drm_crtc_mask(crtc);
> -	ret = drm_encoder_init(dev, encoder, &drm_simple_kms_encoder_funcs,
> -			       DRM_MODE_ENCODER_NONE, NULL);
> +	ret = drm_simple_encoder_init(dev, encoder, DRM_MODE_ENCODER_NONE);
>  	if (ret || !connector)
>  		return ret;
>  
> diff --git a/include/drm/drm_simple_kms_helper.h b/include/drm/drm_simple_kms_helper.h
> index e253ba7bea9d..54d5066d90c7 100644
> --- a/include/drm/drm_simple_kms_helper.h
> +++ b/include/drm/drm_simple_kms_helper.h
> @@ -181,4 +181,11 @@ int drm_simple_display_pipe_init(struct drm_device *dev,
>  			const uint64_t *format_modifiers,
>  			struct drm_connector *connector);
>  
> +int drm_simple_encoder_init(struct drm_device *dev,
> +			    struct drm_encoder *encoder,
> +			    int encoder_type);
> +
> +struct drm_encoder *drm_simple_encoder_create(struct drm_device *dev,
> +					      int encoder_type);
> +
>  #endif /* __LINUX_DRM_SIMPLE_KMS_HELPER_H */
> -- 
> 2.25.0
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

[PATCH v2 2/4] drm/ast: Use simple encoder

[Thomas Zimmermann]

The ast driver uses an empty implementation for its encoder. Replace
the code with the generic simple encoder.

v2:
	* rebase onto new simple-encoder interface

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/gpu/drm/ast/ast_drv.h  |  6 +-----
 drivers/gpu/drm/ast/ast_mode.c | 25 ++++++++-----------------
 2 files changed, 9 insertions(+), 22 deletions(-)

diff --git a/drivers/gpu/drm/ast/ast_drv.h b/drivers/gpu/drm/ast/ast_drv.h
index f5d8780776ae..656d591b154b 100644
--- a/drivers/gpu/drm/ast/ast_drv.h
+++ b/drivers/gpu/drm/ast/ast_drv.h
@@ -121,6 +121,7 @@ struct ast_private {
 		unsigned int next_index;
 	} cursor;
 
+	struct drm_encoder encoder;
 	struct drm_plane primary_plane;
 	struct drm_plane cursor_plane;
 
@@ -238,13 +239,8 @@ struct ast_crtc {
 	u8 offset_x, offset_y;
 };
 
-struct ast_encoder {
-	struct drm_encoder base;
-};
-
 #define to_ast_crtc(x) container_of(x, struct ast_crtc, base)
 #define to_ast_connector(x) container_of(x, struct ast_connector, base)
-#define to_ast_encoder(x) container_of(x, struct ast_encoder, base)
 
 struct ast_vbios_stdtable {
 	u8 misc;
diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c
index 562ea6d9df13..7a9f20a2fd30 100644
--- a/drivers/gpu/drm/ast/ast_mode.c
+++ b/drivers/gpu/drm/ast/ast_mode.c
@@ -40,6 +40,7 @@
 #include <drm/drm_gem_vram_helper.h>
 #include <drm/drm_plane_helper.h>
 #include <drm/drm_probe_helper.h>
+#include <drm/drm_simple_kms_helper.h>
 
 #include "ast_drv.h"
 #include "ast_tables.h"
@@ -968,28 +969,18 @@ static int ast_crtc_init(struct drm_device *dev)
  * Encoder
  */
 
-static void ast_encoder_destroy(struct drm_encoder *encoder)
-{
-	drm_encoder_cleanup(encoder);
-	kfree(encoder);
-}
-
-static const struct drm_encoder_funcs ast_enc_funcs = {
-	.destroy = ast_encoder_destroy,
-};
-
 static int ast_encoder_init(struct drm_device *dev)
 {
-	struct ast_encoder *ast_encoder;
+	struct ast_private *ast = dev->dev_private;
+	struct drm_encoder *encoder = &ast->encoder;
+	int ret;
 
-	ast_encoder = kzalloc(sizeof(struct ast_encoder), GFP_KERNEL);
-	if (!ast_encoder)
-		return -ENOMEM;
+	ret = drm_simple_encoder_init(dev, encoder, DRM_MODE_ENCODER_DAC);
+	if (ret)
+		return ret;
 
-	drm_encoder_init(dev, &ast_encoder->base, &ast_enc_funcs,
-			 DRM_MODE_ENCODER_DAC, NULL);
+	encoder->possible_crtcs = 1;
 
-	ast_encoder->base.possible_crtcs = 1;
 	return 0;
 }
 
-- 
2.25.0

Re: [PATCH v2 2/4] drm/ast: Use simple encoder

[Sam Ravnborg]

Hi Thomas.

On Tue, Feb 18, 2020 at 09:48:13AM +0100, Thomas Zimmermann wrote:
> The ast driver uses an empty implementation for its encoder. Replace
> the code with the generic simple encoder.
> 
> v2:
> 	* rebase onto new simple-encoder interface
> 
> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
From browsign the code - looks good:
Acked-by: Sam Ravnborg <sam@ravnborg.org>

	Sam

> ---
>  drivers/gpu/drm/ast/ast_drv.h  |  6 +-----
>  drivers/gpu/drm/ast/ast_mode.c | 25 ++++++++-----------------
>  2 files changed, 9 insertions(+), 22 deletions(-)
> 
> diff --git a/drivers/gpu/drm/ast/ast_drv.h b/drivers/gpu/drm/ast/ast_drv.h
> index f5d8780776ae..656d591b154b 100644
> --- a/drivers/gpu/drm/ast/ast_drv.h
> +++ b/drivers/gpu/drm/ast/ast_drv.h
> @@ -121,6 +121,7 @@ struct ast_private {
>  		unsigned int next_index;
>  	} cursor;
>  
> +	struct drm_encoder encoder;
>  	struct drm_plane primary_plane;
>  	struct drm_plane cursor_plane;
>  
> @@ -238,13 +239,8 @@ struct ast_crtc {
>  	u8 offset_x, offset_y;
>  };
>  
> -struct ast_encoder {
> -	struct drm_encoder base;
> -};
> -
>  #define to_ast_crtc(x) container_of(x, struct ast_crtc, base)
>  #define to_ast_connector(x) container_of(x, struct ast_connector, base)
> -#define to_ast_encoder(x) container_of(x, struct ast_encoder, base)
>  
>  struct ast_vbios_stdtable {
>  	u8 misc;
> diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c
> index 562ea6d9df13..7a9f20a2fd30 100644
> --- a/drivers/gpu/drm/ast/ast_mode.c
> +++ b/drivers/gpu/drm/ast/ast_mode.c
> @@ -40,6 +40,7 @@
>  #include <drm/drm_gem_vram_helper.h>
>  #include <drm/drm_plane_helper.h>
>  #include <drm/drm_probe_helper.h>
> +#include <drm/drm_simple_kms_helper.h>
>  
>  #include "ast_drv.h"
>  #include "ast_tables.h"
> @@ -968,28 +969,18 @@ static int ast_crtc_init(struct drm_device *dev)
>   * Encoder
>   */
>  
> -static void ast_encoder_destroy(struct drm_encoder *encoder)
> -{
> -	drm_encoder_cleanup(encoder);
> -	kfree(encoder);
> -}
> -
> -static const struct drm_encoder_funcs ast_enc_funcs = {
> -	.destroy = ast_encoder_destroy,
> -};
> -
>  static int ast_encoder_init(struct drm_device *dev)
>  {
> -	struct ast_encoder *ast_encoder;
> +	struct ast_private *ast = dev->dev_private;
> +	struct drm_encoder *encoder = &ast->encoder;
> +	int ret;
>  
> -	ast_encoder = kzalloc(sizeof(struct ast_encoder), GFP_KERNEL);
> -	if (!ast_encoder)
> -		return -ENOMEM;
> +	ret = drm_simple_encoder_init(dev, encoder, DRM_MODE_ENCODER_DAC);
> +	if (ret)
> +		return ret;
>  
> -	drm_encoder_init(dev, &ast_encoder->base, &ast_enc_funcs,
> -			 DRM_MODE_ENCODER_DAC, NULL);
> +	encoder->possible_crtcs = 1;
>  
> -	ast_encoder->base.possible_crtcs = 1;
>  	return 0;
>  }
>  
> -- 
> 2.25.0

[PATCH v2 3/4] drm/mgag200: Use simple encoder

[Thomas Zimmermann]

The mgag200 driver uses an empty implementation for its encoder. Replace
the code with the generic simple encoder.

v2:
	* rebase onto new simple-encoder interface

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/gpu/drm/mgag200/mgag200_drv.h  |  7 ---
 drivers/gpu/drm/mgag200/mgag200_mode.c | 61 ++------------------------
 2 files changed, 3 insertions(+), 65 deletions(-)

diff --git a/drivers/gpu/drm/mgag200/mgag200_drv.h b/drivers/gpu/drm/mgag200/mgag200_drv.h
index aa32aad222c2..9bb9e8e14539 100644
--- a/drivers/gpu/drm/mgag200/mgag200_drv.h
+++ b/drivers/gpu/drm/mgag200/mgag200_drv.h
@@ -95,7 +95,6 @@
 #define MATROX_DPMS_CLEARED (-1)
 
 #define to_mga_crtc(x) container_of(x, struct mga_crtc, base)
-#define to_mga_encoder(x) container_of(x, struct mga_encoder, base)
 #define to_mga_connector(x) container_of(x, struct mga_connector, base)
 
 struct mga_crtc {
@@ -110,12 +109,6 @@ struct mga_mode_info {
 	struct mga_crtc *crtc;
 };
 
-struct mga_encoder {
-	struct drm_encoder base;
-	int last_dpms;
-};
-
-
 struct mga_i2c_chan {
 	struct i2c_adapter adapter;
 	struct drm_device *dev;
diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c b/drivers/gpu/drm/mgag200/mgag200_mode.c
index 62a8e9ccb16d..957ea1057b6c 100644
--- a/drivers/gpu/drm/mgag200/mgag200_mode.c
+++ b/drivers/gpu/drm/mgag200/mgag200_mode.c
@@ -15,6 +15,7 @@
 #include <drm/drm_fourcc.h>
 #include <drm/drm_plane_helper.h>
 #include <drm/drm_probe_helper.h>
+#include <drm/drm_simple_kms_helper.h>
 
 #include "mgag200_drv.h"
 
@@ -1449,72 +1450,16 @@ static void mga_crtc_init(struct mga_device *mdev)
 	drm_crtc_helper_add(&mga_crtc->base, &mga_helper_funcs);
 }
 
-/*
- * The encoder comes after the CRTC in the output pipeline, but before
- * the connector. It's responsible for ensuring that the digital
- * stream is appropriately converted into the output format. Setup is
- * very simple in this case - all we have to do is inform qemu of the
- * colour depth in order to ensure that it displays appropriately
- */
-
-/*
- * These functions are analagous to those in the CRTC code, but are intended
- * to handle any encoder-specific limitations
- */
-static void mga_encoder_mode_set(struct drm_encoder *encoder,
-				struct drm_display_mode *mode,
-				struct drm_display_mode *adjusted_mode)
-{
-
-}
-
-static void mga_encoder_dpms(struct drm_encoder *encoder, int state)
-{
-	return;
-}
-
-static void mga_encoder_prepare(struct drm_encoder *encoder)
-{
-}
-
-static void mga_encoder_commit(struct drm_encoder *encoder)
-{
-}
-
-static void mga_encoder_destroy(struct drm_encoder *encoder)
-{
-	struct mga_encoder *mga_encoder = to_mga_encoder(encoder);
-	drm_encoder_cleanup(encoder);
-	kfree(mga_encoder);
-}
-
-static const struct drm_encoder_helper_funcs mga_encoder_helper_funcs = {
-	.dpms = mga_encoder_dpms,
-	.mode_set = mga_encoder_mode_set,
-	.prepare = mga_encoder_prepare,
-	.commit = mga_encoder_commit,
-};
-
-static const struct drm_encoder_funcs mga_encoder_encoder_funcs = {
-	.destroy = mga_encoder_destroy,
-};
-
 static struct drm_encoder *mga_encoder_init(struct drm_device *dev)
 {
 	struct drm_encoder *encoder;
-	struct mga_encoder *mga_encoder;
 
-	mga_encoder = kzalloc(sizeof(struct mga_encoder), GFP_KERNEL);
-	if (!mga_encoder)
+	encoder = drm_simple_encoder_create(dev, DRM_MODE_ENCODER_DAC);
+	if (IS_ERR(encoder))
 		return NULL;
 
-	encoder = &mga_encoder->base;
 	encoder->possible_crtcs = 0x1;
 
-	drm_encoder_init(dev, encoder, &mga_encoder_encoder_funcs,
-			 DRM_MODE_ENCODER_DAC, NULL);
-	drm_encoder_helper_add(encoder, &mga_encoder_helper_funcs);
-
 	return encoder;
 }
 
-- 
2.25.0

Re: [PATCH v2 3/4] drm/mgag200: Use simple encoder

[Sam Ravnborg]

Hi Thomas.

On Tue, Feb 18, 2020 at 09:48:14AM +0100, Thomas Zimmermann wrote:
> The mgag200 driver uses an empty implementation for its encoder. Replace
> the code with the generic simple encoder.
> 
> v2:
> 	* rebase onto new simple-encoder interface
> 
> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
> ---
>  drivers/gpu/drm/mgag200/mgag200_drv.h  |  7 ---
>  drivers/gpu/drm/mgag200/mgag200_mode.c | 61 ++------------------------
>  2 files changed, 3 insertions(+), 65 deletions(-)
> 
> diff --git a/drivers/gpu/drm/mgag200/mgag200_drv.h b/drivers/gpu/drm/mgag200/mgag200_drv.h
> index aa32aad222c2..9bb9e8e14539 100644
> --- a/drivers/gpu/drm/mgag200/mgag200_drv.h
> +++ b/drivers/gpu/drm/mgag200/mgag200_drv.h
> @@ -95,7 +95,6 @@
>  #define MATROX_DPMS_CLEARED (-1)
>  
>  #define to_mga_crtc(x) container_of(x, struct mga_crtc, base)
> -#define to_mga_encoder(x) container_of(x, struct mga_encoder, base)
>  #define to_mga_connector(x) container_of(x, struct mga_connector, base)
>  
>  struct mga_crtc {
> @@ -110,12 +109,6 @@ struct mga_mode_info {
>  	struct mga_crtc *crtc;
>  };
>  
> -struct mga_encoder {
> -	struct drm_encoder base;
> -	int last_dpms;
> -};
> -
> -
>  struct mga_i2c_chan {
>  	struct i2c_adapter adapter;
>  	struct drm_device *dev;

Any particular reason why the drm_encoder is not embedded in struct
mga_device?

I found it more elegant - like you did it for ast in the previous patch.

I also noted there is one more unused "last_dpms" - but it is outside
the scope of this patch to remove it.

	Sam

> diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c b/drivers/gpu/drm/mgag200/mgag200_mode.c
> index 62a8e9ccb16d..957ea1057b6c 100644
> --- a/drivers/gpu/drm/mgag200/mgag200_mode.c
> +++ b/drivers/gpu/drm/mgag200/mgag200_mode.c
> @@ -15,6 +15,7 @@
>  #include <drm/drm_fourcc.h>
>  #include <drm/drm_plane_helper.h>
>  #include <drm/drm_probe_helper.h>
> +#include <drm/drm_simple_kms_helper.h>
>  
>  #include "mgag200_drv.h"
>  
> @@ -1449,72 +1450,16 @@ static void mga_crtc_init(struct mga_device *mdev)
>  	drm_crtc_helper_add(&mga_crtc->base, &mga_helper_funcs);
>  }
>  
> -/*
> - * The encoder comes after the CRTC in the output pipeline, but before
> - * the connector. It's responsible for ensuring that the digital
> - * stream is appropriately converted into the output format. Setup is
> - * very simple in this case - all we have to do is inform qemu of the
> - * colour depth in order to ensure that it displays appropriately
> - */
> -
> -/*
> - * These functions are analagous to those in the CRTC code, but are intended
> - * to handle any encoder-specific limitations
> - */
> -static void mga_encoder_mode_set(struct drm_encoder *encoder,
> -				struct drm_display_mode *mode,
> -				struct drm_display_mode *adjusted_mode)
> -{
> -
> -}
> -
> -static void mga_encoder_dpms(struct drm_encoder *encoder, int state)
> -{
> -	return;
> -}
> -
> -static void mga_encoder_prepare(struct drm_encoder *encoder)
> -{
> -}
> -
> -static void mga_encoder_commit(struct drm_encoder *encoder)
> -{
> -}
> -
> -static void mga_encoder_destroy(struct drm_encoder *encoder)
> -{
> -	struct mga_encoder *mga_encoder = to_mga_encoder(encoder);
> -	drm_encoder_cleanup(encoder);
> -	kfree(mga_encoder);
> -}
> -
> -static const struct drm_encoder_helper_funcs mga_encoder_helper_funcs = {
> -	.dpms = mga_encoder_dpms,
> -	.mode_set = mga_encoder_mode_set,
> -	.prepare = mga_encoder_prepare,
> -	.commit = mga_encoder_commit,
> -};
> -
> -static const struct drm_encoder_funcs mga_encoder_encoder_funcs = {
> -	.destroy = mga_encoder_destroy,
> -};
> -
>  static struct drm_encoder *mga_encoder_init(struct drm_device *dev)
>  {
>  	struct drm_encoder *encoder;
> -	struct mga_encoder *mga_encoder;
>  
> -	mga_encoder = kzalloc(sizeof(struct mga_encoder), GFP_KERNEL);
> -	if (!mga_encoder)
> +	encoder = drm_simple_encoder_create(dev, DRM_MODE_ENCODER_DAC);
> +	if (IS_ERR(encoder))
>  		return NULL;
>  
> -	encoder = &mga_encoder->base;
>  	encoder->possible_crtcs = 0x1;
>  
> -	drm_encoder_init(dev, encoder, &mga_encoder_encoder_funcs,
> -			 DRM_MODE_ENCODER_DAC, NULL);
> -	drm_encoder_helper_add(encoder, &mga_encoder_helper_funcs);
> -
>  	return encoder;
>  }
>  
> -- 
> 2.25.0

Re: [PATCH v2 3/4] drm/mgag200: Use simple encoder

[Thomas Zimmermann]

[-- Attachment #1.1.1: Type: text/plain, Size: 4987 bytes --]

Hi Sam

thanks for reviewing the patch set.

Am 20.02.20 um 19:56 schrieb Sam Ravnborg:
> Hi Thomas.
> 
> On Tue, Feb 18, 2020 at 09:48:14AM +0100, Thomas Zimmermann wrote:
>> The mgag200 driver uses an empty implementation for its encoder. Replace
>> the code with the generic simple encoder.
>>
>> v2:
>> 	* rebase onto new simple-encoder interface
>>
>> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
>> ---
>>  drivers/gpu/drm/mgag200/mgag200_drv.h  |  7 ---
>>  drivers/gpu/drm/mgag200/mgag200_mode.c | 61 ++------------------------
>>  2 files changed, 3 insertions(+), 65 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/mgag200/mgag200_drv.h b/drivers/gpu/drm/mgag200/mgag200_drv.h
>> index aa32aad222c2..9bb9e8e14539 100644
>> --- a/drivers/gpu/drm/mgag200/mgag200_drv.h
>> +++ b/drivers/gpu/drm/mgag200/mgag200_drv.h
>> @@ -95,7 +95,6 @@
>>  #define MATROX_DPMS_CLEARED (-1)
>>  
>>  #define to_mga_crtc(x) container_of(x, struct mga_crtc, base)
>> -#define to_mga_encoder(x) container_of(x, struct mga_encoder, base)
>>  #define to_mga_connector(x) container_of(x, struct mga_connector, base)
>>  
>>  struct mga_crtc {
>> @@ -110,12 +109,6 @@ struct mga_mode_info {
>>  	struct mga_crtc *crtc;
>>  };
>>  
>> -struct mga_encoder {
>> -	struct drm_encoder base;
>> -	int last_dpms;
>> -};
>> -
>> -
>>  struct mga_i2c_chan {
>>  	struct i2c_adapter adapter;
>>  	struct drm_device *dev;
> 
> Any particular reason why the drm_encoder is not embedded in struct
> mga_device?
> 
> I found it more elegant - like you did it for ast in the previous patch.

I think I wanted something that uses drm_simple_encoder_create(). But I
can change that. The embedded variant is indeed better.

Best regards
Thomas

> 
> I also noted there is one more unused "last_dpms" - but it is outside
> the scope of this patch to remove it.
> 
> 	Sam
> 
>> diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c b/drivers/gpu/drm/mgag200/mgag200_mode.c
>> index 62a8e9ccb16d..957ea1057b6c 100644
>> --- a/drivers/gpu/drm/mgag200/mgag200_mode.c
>> +++ b/drivers/gpu/drm/mgag200/mgag200_mode.c
>> @@ -15,6 +15,7 @@
>>  #include <drm/drm_fourcc.h>
>>  #include <drm/drm_plane_helper.h>
>>  #include <drm/drm_probe_helper.h>
>> +#include <drm/drm_simple_kms_helper.h>
>>  
>>  #include "mgag200_drv.h"
>>  
>> @@ -1449,72 +1450,16 @@ static void mga_crtc_init(struct mga_device *mdev)
>>  	drm_crtc_helper_add(&mga_crtc->base, &mga_helper_funcs);
>>  }
>>  
>> -/*
>> - * The encoder comes after the CRTC in the output pipeline, but before
>> - * the connector. It's responsible for ensuring that the digital
>> - * stream is appropriately converted into the output format. Setup is
>> - * very simple in this case - all we have to do is inform qemu of the
>> - * colour depth in order to ensure that it displays appropriately
>> - */
>> -
>> -/*
>> - * These functions are analagous to those in the CRTC code, but are intended
>> - * to handle any encoder-specific limitations
>> - */
>> -static void mga_encoder_mode_set(struct drm_encoder *encoder,
>> -				struct drm_display_mode *mode,
>> -				struct drm_display_mode *adjusted_mode)
>> -{
>> -
>> -}
>> -
>> -static void mga_encoder_dpms(struct drm_encoder *encoder, int state)
>> -{
>> -	return;
>> -}
>> -
>> -static void mga_encoder_prepare(struct drm_encoder *encoder)
>> -{
>> -}
>> -
>> -static void mga_encoder_commit(struct drm_encoder *encoder)
>> -{
>> -}
>> -
>> -static void mga_encoder_destroy(struct drm_encoder *encoder)
>> -{
>> -	struct mga_encoder *mga_encoder = to_mga_encoder(encoder);
>> -	drm_encoder_cleanup(encoder);
>> -	kfree(mga_encoder);
>> -}
>> -
>> -static const struct drm_encoder_helper_funcs mga_encoder_helper_funcs = {
>> -	.dpms = mga_encoder_dpms,
>> -	.mode_set = mga_encoder_mode_set,
>> -	.prepare = mga_encoder_prepare,
>> -	.commit = mga_encoder_commit,
>> -};
>> -
>> -static const struct drm_encoder_funcs mga_encoder_encoder_funcs = {
>> -	.destroy = mga_encoder_destroy,
>> -};
>> -
>>  static struct drm_encoder *mga_encoder_init(struct drm_device *dev)
>>  {
>>  	struct drm_encoder *encoder;
>> -	struct mga_encoder *mga_encoder;
>>  
>> -	mga_encoder = kzalloc(sizeof(struct mga_encoder), GFP_KERNEL);
>> -	if (!mga_encoder)
>> +	encoder = drm_simple_encoder_create(dev, DRM_MODE_ENCODER_DAC);
>> +	if (IS_ERR(encoder))
>>  		return NULL;
>>  
>> -	encoder = &mga_encoder->base;
>>  	encoder->possible_crtcs = 0x1;
>>  
>> -	drm_encoder_init(dev, encoder, &mga_encoder_encoder_funcs,
>> -			 DRM_MODE_ENCODER_DAC, NULL);
>> -	drm_encoder_helper_add(encoder, &mga_encoder_helper_funcs);
>> -
>>  	return encoder;
>>  }
>>  
>> -- 
>> 2.25.0

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


[-- Attachment #1.2: OpenPGP digital signature --]
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[-- Attachment #2: Type: text/plain, Size: 183 bytes --]

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Re: [PATCH v2 3/4] drm/mgag200: Use simple encoder

[Sam Ravnborg]

Hi Thomas.

On Fri, Feb 21, 2020 at 08:48:48AM +0100, Thomas Zimmermann wrote:
> Hi Sam
> 
> thanks for reviewing the patch set.
> 
> Am 20.02.20 um 19:56 schrieb Sam Ravnborg:
> > Hi Thomas.
> > 
> > On Tue, Feb 18, 2020 at 09:48:14AM +0100, Thomas Zimmermann wrote:
> >> The mgag200 driver uses an empty implementation for its encoder. Replace
> >> the code with the generic simple encoder.
> >>
> >> v2:
> >> 	* rebase onto new simple-encoder interface
> >>
> >> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
> >> ---
> >>  drivers/gpu/drm/mgag200/mgag200_drv.h  |  7 ---
> >>  drivers/gpu/drm/mgag200/mgag200_mode.c | 61 ++------------------------
> >>  2 files changed, 3 insertions(+), 65 deletions(-)
> >>
> >> diff --git a/drivers/gpu/drm/mgag200/mgag200_drv.h b/drivers/gpu/drm/mgag200/mgag200_drv.h
> >> index aa32aad222c2..9bb9e8e14539 100644
> >> --- a/drivers/gpu/drm/mgag200/mgag200_drv.h
> >> +++ b/drivers/gpu/drm/mgag200/mgag200_drv.h
> >> @@ -95,7 +95,6 @@
> >>  #define MATROX_DPMS_CLEARED (-1)
> >>  
> >>  #define to_mga_crtc(x) container_of(x, struct mga_crtc, base)
> >> -#define to_mga_encoder(x) container_of(x, struct mga_encoder, base)
> >>  #define to_mga_connector(x) container_of(x, struct mga_connector, base)
> >>  
> >>  struct mga_crtc {
> >> @@ -110,12 +109,6 @@ struct mga_mode_info {
> >>  	struct mga_crtc *crtc;
> >>  };
> >>  
> >> -struct mga_encoder {
> >> -	struct drm_encoder base;
> >> -	int last_dpms;
> >> -};
> >> -
> >> -
> >>  struct mga_i2c_chan {
> >>  	struct i2c_adapter adapter;
> >>  	struct drm_device *dev;
> > 
> > Any particular reason why the drm_encoder is not embedded in struct
> > mga_device?
> > 
> > I found it more elegant - like you did it for ast in the previous patch.
> 
> I think I wanted something that uses drm_simple_encoder_create(). But I
> can change that. The embedded variant is indeed better.

You should consider to drop drm_simple_encoder_create() until there
is a driver that really needs it.

	Sam

Re: [PATCH v2 3/4] drm/mgag200: Use simple encoder

[Daniel Vetter]

On Fri, Feb 21, 2020 at 08:00:57PM +0100, Sam Ravnborg wrote:
> Hi Thomas.
> 
> On Fri, Feb 21, 2020 at 08:48:48AM +0100, Thomas Zimmermann wrote:
> > Hi Sam
> > 
> > thanks for reviewing the patch set.
> > 
> > Am 20.02.20 um 19:56 schrieb Sam Ravnborg:
> > > Hi Thomas.
> > > 
> > > On Tue, Feb 18, 2020 at 09:48:14AM +0100, Thomas Zimmermann wrote:
> > >> The mgag200 driver uses an empty implementation for its encoder. Replace
> > >> the code with the generic simple encoder.
> > >>
> > >> v2:
> > >> 	* rebase onto new simple-encoder interface
> > >>
> > >> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
> > >> ---
> > >>  drivers/gpu/drm/mgag200/mgag200_drv.h  |  7 ---
> > >>  drivers/gpu/drm/mgag200/mgag200_mode.c | 61 ++------------------------
> > >>  2 files changed, 3 insertions(+), 65 deletions(-)
> > >>
> > >> diff --git a/drivers/gpu/drm/mgag200/mgag200_drv.h b/drivers/gpu/drm/mgag200/mgag200_drv.h
> > >> index aa32aad222c2..9bb9e8e14539 100644
> > >> --- a/drivers/gpu/drm/mgag200/mgag200_drv.h
> > >> +++ b/drivers/gpu/drm/mgag200/mgag200_drv.h
> > >> @@ -95,7 +95,6 @@
> > >>  #define MATROX_DPMS_CLEARED (-1)
> > >>  
> > >>  #define to_mga_crtc(x) container_of(x, struct mga_crtc, base)
> > >> -#define to_mga_encoder(x) container_of(x, struct mga_encoder, base)
> > >>  #define to_mga_connector(x) container_of(x, struct mga_connector, base)
> > >>  
> > >>  struct mga_crtc {
> > >> @@ -110,12 +109,6 @@ struct mga_mode_info {
> > >>  	struct mga_crtc *crtc;
> > >>  };
> > >>  
> > >> -struct mga_encoder {
> > >> -	struct drm_encoder base;
> > >> -	int last_dpms;
> > >> -};
> > >> -
> > >> -
> > >>  struct mga_i2c_chan {
> > >>  	struct i2c_adapter adapter;
> > >>  	struct drm_device *dev;
> > > 
> > > Any particular reason why the drm_encoder is not embedded in struct
> > > mga_device?
> > > 
> > > I found it more elegant - like you did it for ast in the previous patch.
> > 
> > I think I wanted something that uses drm_simple_encoder_create(). But I
> > can change that. The embedded variant is indeed better.
> 
> You should consider to drop drm_simple_encoder_create() until there
> is a driver that really needs it.

Yeah +1 on only the _init version. The create version really should use
drmm_kzalloc I think, but we're not quite there yet :-)
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

[PATCH v2 4/4] drm/qxl: Use simple encoder

[Thomas Zimmermann]

The qxl driver uses an empty implementation for its encoder. Replace
the code with the generic simple encoder.

v2:
	* rebase onto new simple-encoder interface

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/gpu/drm/qxl/qxl_display.c | 18 +++---------------
 1 file changed, 3 insertions(+), 15 deletions(-)

diff --git a/drivers/gpu/drm/qxl/qxl_display.c b/drivers/gpu/drm/qxl/qxl_display.c
index ab4f8dd00400..9c0e1add59fb 100644
--- a/drivers/gpu/drm/qxl/qxl_display.c
+++ b/drivers/gpu/drm/qxl/qxl_display.c
@@ -31,6 +31,7 @@
 #include <drm/drm_gem_framebuffer_helper.h>
 #include <drm/drm_plane_helper.h>
 #include <drm/drm_probe_helper.h>
+#include <drm/drm_simple_kms_helper.h>
 
 #include "qxl_drv.h"
 #include "qxl_object.h"
@@ -1007,9 +1008,6 @@ static struct drm_encoder *qxl_best_encoder(struct drm_connector *connector)
 	return &qxl_output->enc;
 }
 
-static const struct drm_encoder_helper_funcs qxl_enc_helper_funcs = {
-};
-
 static const struct drm_connector_helper_funcs qxl_connector_helper_funcs = {
 	.get_modes = qxl_conn_get_modes,
 	.mode_valid = qxl_conn_mode_valid,
@@ -1059,15 +1057,6 @@ static const struct drm_connector_funcs qxl_connector_funcs = {
 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
 };
 
-static void qxl_enc_destroy(struct drm_encoder *encoder)
-{
-	drm_encoder_cleanup(encoder);
-}
-
-static const struct drm_encoder_funcs qxl_enc_funcs = {
-	.destroy = qxl_enc_destroy,
-};
-
 static int qxl_mode_create_hotplug_mode_update_property(struct qxl_device *qdev)
 {
 	if (qdev->hotplug_mode_update_property)
@@ -1098,15 +1087,14 @@ static int qdev_output_init(struct drm_device *dev, int num_output)
 	drm_connector_init(dev, &qxl_output->base,
 			   &qxl_connector_funcs, DRM_MODE_CONNECTOR_VIRTUAL);
 
-	drm_encoder_init(dev, &qxl_output->enc, &qxl_enc_funcs,
-			 DRM_MODE_ENCODER_VIRTUAL, NULL);
+	drm_simple_encoder_init(dev, &qxl_output->enc,
+				DRM_MODE_ENCODER_VIRTUAL);
 
 	/* we get HPD via client monitors config */
 	connector->polled = DRM_CONNECTOR_POLL_HPD;
 	encoder->possible_crtcs = 1 << num_output;
 	drm_connector_attach_encoder(&qxl_output->base,
 					  &qxl_output->enc);
-	drm_encoder_helper_add(encoder, &qxl_enc_helper_funcs);
 	drm_connector_helper_add(connector, &qxl_connector_helper_funcs);
 
 	drm_object_attach_property(&connector->base,
-- 
2.25.0

Re: [PATCH v2 4/4] drm/qxl: Use simple encoder

[Sam Ravnborg]

Hi Thomas.

On Tue, Feb 18, 2020 at 09:48:15AM +0100, Thomas Zimmermann wrote:
> The qxl driver uses an empty implementation for its encoder. Replace
> the code with the generic simple encoder.
> 
> v2:
> 	* rebase onto new simple-encoder interface
> 
> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
I looked at best_encoder - but could not see we could do anything.
So from browsing the code:
Acked-by: Sam Ravnborg <sam@ravnborg.org>

	Sam

> ---
>  drivers/gpu/drm/qxl/qxl_display.c | 18 +++---------------
>  1 file changed, 3 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/gpu/drm/qxl/qxl_display.c b/drivers/gpu/drm/qxl/qxl_display.c
> index ab4f8dd00400..9c0e1add59fb 100644
> --- a/drivers/gpu/drm/qxl/qxl_display.c
> +++ b/drivers/gpu/drm/qxl/qxl_display.c
> @@ -31,6 +31,7 @@
>  #include <drm/drm_gem_framebuffer_helper.h>
>  #include <drm/drm_plane_helper.h>
>  #include <drm/drm_probe_helper.h>
> +#include <drm/drm_simple_kms_helper.h>
>  
>  #include "qxl_drv.h"
>  #include "qxl_object.h"
> @@ -1007,9 +1008,6 @@ static struct drm_encoder *qxl_best_encoder(struct drm_connector *connector)
>  	return &qxl_output->enc;
>  }
>  
> -static const struct drm_encoder_helper_funcs qxl_enc_helper_funcs = {
> -};
> -
>  static const struct drm_connector_helper_funcs qxl_connector_helper_funcs = {
>  	.get_modes = qxl_conn_get_modes,
>  	.mode_valid = qxl_conn_mode_valid,
> @@ -1059,15 +1057,6 @@ static const struct drm_connector_funcs qxl_connector_funcs = {
>  	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
>  };
>  
> -static void qxl_enc_destroy(struct drm_encoder *encoder)
> -{
> -	drm_encoder_cleanup(encoder);
> -}
> -
> -static const struct drm_encoder_funcs qxl_enc_funcs = {
> -	.destroy = qxl_enc_destroy,
> -};
> -
>  static int qxl_mode_create_hotplug_mode_update_property(struct qxl_device *qdev)
>  {
>  	if (qdev->hotplug_mode_update_property)
> @@ -1098,15 +1087,14 @@ static int qdev_output_init(struct drm_device *dev, int num_output)
>  	drm_connector_init(dev, &qxl_output->base,
>  			   &qxl_connector_funcs, DRM_MODE_CONNECTOR_VIRTUAL);
>  
> -	drm_encoder_init(dev, &qxl_output->enc, &qxl_enc_funcs,
> -			 DRM_MODE_ENCODER_VIRTUAL, NULL);
> +	drm_simple_encoder_init(dev, &qxl_output->enc,
> +				DRM_MODE_ENCODER_VIRTUAL);
>  
>  	/* we get HPD via client monitors config */
>  	connector->polled = DRM_CONNECTOR_POLL_HPD;
>  	encoder->possible_crtcs = 1 << num_output;
>  	drm_connector_attach_encoder(&qxl_output->base,
>  					  &qxl_output->enc);
> -	drm_encoder_helper_add(encoder, &qxl_enc_helper_funcs);
>  	drm_connector_helper_add(connector, &qxl_connector_helper_funcs);
>  
>  	drm_object_attach_property(&connector->base,
> -- 
> 2.25.0

Re: [PATCH v2 4/4] drm/qxl: Use simple encoder

[Gerd Hoffmann]

On Tue, Feb 18, 2020 at 09:48:15AM +0100, Thomas Zimmermann wrote:
> The qxl driver uses an empty implementation for its encoder. Replace
> the code with the generic simple encoder.
> 
> v2:
> 	* rebase onto new simple-encoder interface
> 
> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Acked-by: Gerd Hoffmann <kraxel@redhat.com>