[RFC,v3,14/14] drm/vkms: Introduce configfs for encoder type

Commit Message

Louis Chauvet Jan. 21, 2025, 2:34 p.m. UTC

In order to support multiple configuration, add the possibility to change
the encoder type.

Signed-off-by: Louis Chauvet <[e-mail]>
---
 drivers/gpu/drm/vkms/vkms_configfs.c | 57 ++++++++++++++++++++++++++++++++++++
 1 file changed, 57 insertions(+)

Patch

diff --git a/drivers/gpu/drm/vkms/vkms_configfs.c b/drivers/gpu/drm/vkms/vkms_configfs.c
index 547b76d67c4cd1f9c2fb20e45f0f0583fa03b59a..dd4de385dadbdb24647cc59debb0284f94033b4b 100644
--- a/drivers/gpu/drm/vkms/vkms_configfs.c
+++ b/drivers/gpu/drm/vkms/vkms_configfs.c
@@ -1,5 +1,6 @@ 
 // SPDX-License-Identifier: GPL-2.0+
 
+#include "drm/drm_mode.h"
 #include <linux/configfs.h>
 #include <linux/mutex.h>
 #include <drm/drm_print.h>
@@ -544,6 +545,61 @@  static void encoder_possible_crtcs_drop_link(struct config_item *src,
 	mutex_unlock(&vkms_configfs->lock);
 }
 
+static ssize_t encoder_type_show(struct config_item *item, char *page)
+{
+	struct vkms_config_encoder *encoder;
+	char encoder_type = DRM_MODE_ENCODER_NONE;
+	struct vkms_configfs_device *vkms_configfs = encoder_item_to_vkms_configfs_device(item);
+
+	scoped_guard(mutex, &vkms_configfs->lock)
+	{
+		encoder = encoder_item_to_vkms_configfs_encoder(item)->vkms_config_encoder;
+		encoder_type = encoder->type;
+	}
+
+	return sprintf(page, "%u", encoder_type);
+}
+
+static ssize_t encoder_type_store(struct config_item *item,
+				  const char *page, size_t count)
+{
+	struct vkms_configfs_device *vkms_configfs = encoder_item_to_vkms_configfs_device(item);
+	int val = DRM_MODE_ENCODER_VIRTUAL;
+	struct vkms_config_encoder *encoder;
+	int ret;
+
+	ret = kstrtouint(page, 10, &val);
+	if (ret)
+		return ret;
+
+	if (val != DRM_MODE_ENCODER_DAC &&
+	    val != DRM_MODE_ENCODER_DPI &&
+	    val != DRM_MODE_ENCODER_DSI &&
+	    val != DRM_MODE_ENCODER_LVDS &&
+	    val != DRM_MODE_ENCODER_NONE &&
+	    val != DRM_MODE_ENCODER_TMDS &&
+	    val != DRM_MODE_ENCODER_TVDAC &&
+	    val != DRM_MODE_ENCODER_VIRTUAL)
+		return -EINVAL;
+
+	scoped_guard(mutex, &vkms_configfs->lock) {
+		if (vkms_configfs->enabled)
+			return -EINVAL;
+
+		encoder = encoder_item_to_vkms_configfs_encoder(item)->vkms_config_encoder;
+		encoder->type = val;
+	}
+
+	return count;
+}
+
+CONFIGFS_ATTR(encoder_, type);
+
+static struct configfs_attribute *encoder_attrs[] = {
+	&encoder_attr_type,
+	NULL,
+};
+
 static struct configfs_item_operations encoder_possible_crtcs_item_operations = {
 	.allow_link	= &encoder_possible_crtcs_allow_link,
 	.drop_link	= &encoder_possible_crtcs_drop_link,
@@ -572,6 +628,7 @@  static struct configfs_item_operations encoder_item_operations = {
 
 static const struct config_item_type encoder_item_type = {
 	.ct_item_ops	= &encoder_item_operations,
+	.ct_attrs       = encoder_attrs,
 	.ct_owner	= THIS_MODULE,
 };