diff mbox series

[v4,02/15] drm/edid: Break out reading block 0 of the EDID

Message ID 20210909135838.v4.2.I62e76a034ac78c994d40a23cd4ec5aeee56fa77c@changeid
State Superseded
Headers show
Series eDP: Support probing eDP panels dynamically instead of hardcoding | expand

Commit Message

Doug Anderson Sept. 9, 2021, 9 p.m. UTC
A future change wants to be able to read just block 0 of the EDID, so
break it out of drm_do_get_edid() into a sub-function.

This is intended to be a no-op change--just code movement.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
---

Changes in v4:
- "u8 *edid" => "void *edid" to avoid cast.
- Don't put kmalloc() in the "if" test even if the old code did.
- drm_do_get_edid_blk0() => drm_do_get_edid_base_block()

 drivers/gpu/drm/drm_edid.c | 63 +++++++++++++++++++++++++++-----------
 1 file changed, 45 insertions(+), 18 deletions(-)

Comments

Jani Nikula Sept. 14, 2021, 6:50 p.m. UTC | #1
On Thu, 09 Sep 2021, Douglas Anderson <dianders@chromium.org> wrote:
> A future change wants to be able to read just block 0 of the EDID, so

> break it out of drm_do_get_edid() into a sub-function.

>

> This is intended to be a no-op change--just code movement.

>

> Signed-off-by: Douglas Anderson <dianders@chromium.org>

> Acked-by: Sam Ravnborg <sam@ravnborg.org>


Reviewed-by: Jani Nikula <jani.nikula@intel.com>


> ---

>

> Changes in v4:

> - "u8 *edid" => "void *edid" to avoid cast.

> - Don't put kmalloc() in the "if" test even if the old code did.

> - drm_do_get_edid_blk0() => drm_do_get_edid_base_block()

>

>  drivers/gpu/drm/drm_edid.c | 63 +++++++++++++++++++++++++++-----------

>  1 file changed, 45 insertions(+), 18 deletions(-)

>

> diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c

> index 6325877c5fd6..520fe1391769 100644

> --- a/drivers/gpu/drm/drm_edid.c

> +++ b/drivers/gpu/drm/drm_edid.c

> @@ -1905,6 +1905,44 @@ int drm_add_override_edid_modes(struct drm_connector *connector)

>  }

>  EXPORT_SYMBOL(drm_add_override_edid_modes);

>  

> +static struct edid *drm_do_get_edid_base_block(

> +	int (*get_edid_block)(void *data, u8 *buf, unsigned int block,

> +			      size_t len),

> +	void *data, bool *edid_corrupt, int *null_edid_counter)

> +{

> +	int i;

> +	void *edid;

> +

> +	edid = kmalloc(EDID_LENGTH, GFP_KERNEL);

> +	if (edid == NULL)

> +		return NULL;

> +

> +	/* base block fetch */

> +	for (i = 0; i < 4; i++) {

> +		if (get_edid_block(data, edid, 0, EDID_LENGTH))

> +			goto out;

> +		if (drm_edid_block_valid(edid, 0, false, edid_corrupt))

> +			break;

> +		if (i == 0 && drm_edid_is_zero(edid, EDID_LENGTH)) {

> +			if (null_edid_counter)

> +				(*null_edid_counter)++;

> +			goto carp;

> +		}

> +	}

> +	if (i == 4)

> +		goto carp;

> +

> +	return edid;

> +

> +carp:

> +	kfree(edid);

> +	return ERR_PTR(-EINVAL);

> +

> +out:

> +	kfree(edid);

> +	return NULL;

> +}

> +

>  /**

>   * drm_do_get_edid - get EDID data using a custom EDID block read function

>   * @connector: connector we're probing

> @@ -1938,25 +1976,16 @@ struct edid *drm_do_get_edid(struct drm_connector *connector,

>  	if (override)

>  		return override;

>  

> -	if ((edid = kmalloc(EDID_LENGTH, GFP_KERNEL)) == NULL)

> +	edid = (u8 *)drm_do_get_edid_base_block(get_edid_block, data,

> +						&connector->edid_corrupt,

> +						&connector->null_edid_counter);

> +	if (IS_ERR_OR_NULL(edid)) {

> +		if (IS_ERR(edid))

> +			connector_bad_edid(connector, edid, 1);

>  		return NULL;

> -

> -	/* base block fetch */

> -	for (i = 0; i < 4; i++) {

> -		if (get_edid_block(data, edid, 0, EDID_LENGTH))

> -			goto out;

> -		if (drm_edid_block_valid(edid, 0, false,

> -					 &connector->edid_corrupt))

> -			break;

> -		if (i == 0 && drm_edid_is_zero(edid, EDID_LENGTH)) {

> -			connector->null_edid_counter++;

> -			goto carp;

> -		}

>  	}

> -	if (i == 4)

> -		goto carp;

>  

> -	/* if there's no extensions, we're done */

> +	/* if there's no extensions or no connector, we're done */

>  	valid_extensions = edid[0x7e];

>  	if (valid_extensions == 0)

>  		return (struct edid *)edid;

> @@ -2010,8 +2039,6 @@ struct edid *drm_do_get_edid(struct drm_connector *connector,

>  

>  	return (struct edid *)edid;

>  

> -carp:

> -	connector_bad_edid(connector, edid, 1);

>  out:

>  	kfree(edid);

>  	return NULL;


-- 
Jani Nikula, Intel Open Source Graphics Center
diff mbox series

Patch

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 6325877c5fd6..520fe1391769 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -1905,6 +1905,44 @@  int drm_add_override_edid_modes(struct drm_connector *connector)
 }
 EXPORT_SYMBOL(drm_add_override_edid_modes);
 
+static struct edid *drm_do_get_edid_base_block(
+	int (*get_edid_block)(void *data, u8 *buf, unsigned int block,
+			      size_t len),
+	void *data, bool *edid_corrupt, int *null_edid_counter)
+{
+	int i;
+	void *edid;
+
+	edid = kmalloc(EDID_LENGTH, GFP_KERNEL);
+	if (edid == NULL)
+		return NULL;
+
+	/* base block fetch */
+	for (i = 0; i < 4; i++) {
+		if (get_edid_block(data, edid, 0, EDID_LENGTH))
+			goto out;
+		if (drm_edid_block_valid(edid, 0, false, edid_corrupt))
+			break;
+		if (i == 0 && drm_edid_is_zero(edid, EDID_LENGTH)) {
+			if (null_edid_counter)
+				(*null_edid_counter)++;
+			goto carp;
+		}
+	}
+	if (i == 4)
+		goto carp;
+
+	return edid;
+
+carp:
+	kfree(edid);
+	return ERR_PTR(-EINVAL);
+
+out:
+	kfree(edid);
+	return NULL;
+}
+
 /**
  * drm_do_get_edid - get EDID data using a custom EDID block read function
  * @connector: connector we're probing
@@ -1938,25 +1976,16 @@  struct edid *drm_do_get_edid(struct drm_connector *connector,
 	if (override)
 		return override;
 
-	if ((edid = kmalloc(EDID_LENGTH, GFP_KERNEL)) == NULL)
+	edid = (u8 *)drm_do_get_edid_base_block(get_edid_block, data,
+						&connector->edid_corrupt,
+						&connector->null_edid_counter);
+	if (IS_ERR_OR_NULL(edid)) {
+		if (IS_ERR(edid))
+			connector_bad_edid(connector, edid, 1);
 		return NULL;
-
-	/* base block fetch */
-	for (i = 0; i < 4; i++) {
-		if (get_edid_block(data, edid, 0, EDID_LENGTH))
-			goto out;
-		if (drm_edid_block_valid(edid, 0, false,
-					 &connector->edid_corrupt))
-			break;
-		if (i == 0 && drm_edid_is_zero(edid, EDID_LENGTH)) {
-			connector->null_edid_counter++;
-			goto carp;
-		}
 	}
-	if (i == 4)
-		goto carp;
 
-	/* if there's no extensions, we're done */
+	/* if there's no extensions or no connector, we're done */
 	valid_extensions = edid[0x7e];
 	if (valid_extensions == 0)
 		return (struct edid *)edid;
@@ -2010,8 +2039,6 @@  struct edid *drm_do_get_edid(struct drm_connector *connector,
 
 	return (struct edid *)edid;
 
-carp:
-	connector_bad_edid(connector, edid, 1);
 out:
 	kfree(edid);
 	return NULL;