drivers/gpu/drm/nouveau/nv50_dac.c - kernel/msm-4.9 - Gitiles

 /*
  * Copyright (C) 2008 Maarten Maathuis.
  * All Rights Reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining
  * a copy of this software and associated documentation files (the
  * "Software"), to deal in the Software without restriction, including
  * without limitation the rights to use, copy, modify, merge, publish,
  * distribute, sublicense, and/or sell copies of the Software, and to
  * permit persons to whom the Software is furnished to do so, subject to
  * the following conditions:
  *
  * The above copyright notice and this permission notice (including the
  * next paragraph) shall be included in all copies or substantial
  * portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  *
  */

 #include "drmP.h"
 #include "drm_crtc_helper.h"

 #define NOUVEAU_DMA_DEBUG (nouveau_reg_debug & NOUVEAU_REG_DEBUG_EVO)
 #include "nouveau_reg.h"
 #include "nouveau_drv.h"
 #include "nouveau_dma.h"
 #include "nouveau_encoder.h"
 #include "nouveau_connector.h"
 #include "nouveau_crtc.h"
 #include "nv50_display.h"

 static void
 nv50_dac_disconnect(struct nouveau_encoder *nv_encoder)
 {
 	struct drm_device *dev = to_drm_encoder(nv_encoder)->dev;
 	struct drm_nouveau_private *dev_priv = dev->dev_private;
 	struct nouveau_channel *evo = dev_priv->evo;
 	int ret;

 	NV_DEBUG(dev, "Disconnecting DAC %d\n", nv_encoder->or);

 	ret = RING_SPACE(evo, 2);
 	if (ret) {
 		NV_ERROR(dev, "no space while disconnecting DAC\n");
 		return;
 	}
 	BEGIN_RING(evo, 0, NV50_EVO_DAC(nv_encoder->or, MODE_CTRL), 1);
 	OUT_RING(evo, 0);
 }

 static enum drm_connector_status
 nv50_dac_detect(struct drm_encoder *encoder, struct drm_connector *connector)
 {
 	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
 	struct drm_device *dev = encoder->dev;
 	struct drm_nouveau_private *dev_priv = dev->dev_private;
 	enum drm_connector_status status = connector_status_disconnected;
 	uint32_t dpms_state, load_pattern, load_state;
 	int or = nv_encoder->or;

 	nv_wr32(dev, NV50_PDISPLAY_DAC_CLK_CTRL1(or), 0x00000001);
 	dpms_state = nv_rd32(dev, NV50_PDISPLAY_DAC_DPMS_CTRL(or));

 	nv_wr32(dev, NV50_PDISPLAY_DAC_DPMS_CTRL(or),
 		0x00150000 | NV50_PDISPLAY_DAC_DPMS_CTRL_PENDING);
 	if (!nv_wait(NV50_PDISPLAY_DAC_DPMS_CTRL(or),
 		     NV50_PDISPLAY_DAC_DPMS_CTRL_PENDING, 0)) {
 		NV_ERROR(dev, "timeout: DAC_DPMS_CTRL_PENDING(%d) == 0\n", or);
 		NV_ERROR(dev, "DAC_DPMS_CTRL(%d) = 0x%08x\n", or,
 			  nv_rd32(dev, NV50_PDISPLAY_DAC_DPMS_CTRL(or)));
 		return status;
 	}

 	/* Use bios provided value if possible. */
 	if (dev_priv->vbios->dactestval) {
 		load_pattern = dev_priv->vbios->dactestval;
 		NV_DEBUG(dev, "Using bios provided load_pattern of %d\n",
 			  load_pattern);
 	} else {
 		load_pattern = 340;
 		NV_DEBUG(dev, "Using default load_pattern of %d\n",
 			 load_pattern);
 	}

 	nv_wr32(dev, NV50_PDISPLAY_DAC_LOAD_CTRL(or),
 		NV50_PDISPLAY_DAC_LOAD_CTRL_ACTIVE | load_pattern);
 	mdelay(45); /* give it some time to process */
 	load_state = nv_rd32(dev, NV50_PDISPLAY_DAC_LOAD_CTRL(or));

 	nv_wr32(dev, NV50_PDISPLAY_DAC_LOAD_CTRL(or), 0);
 	nv_wr32(dev, NV50_PDISPLAY_DAC_DPMS_CTRL(or), dpms_state |
 		NV50_PDISPLAY_DAC_DPMS_CTRL_PENDING);

 	if ((load_state & NV50_PDISPLAY_DAC_LOAD_CTRL_PRESENT) ==
 			  NV50_PDISPLAY_DAC_LOAD_CTRL_PRESENT)
 		status = connector_status_connected;

 	if (status == connector_status_connected)
 		NV_DEBUG(dev, "Load was detected on output with or %d\n", or);
 	else
 		NV_DEBUG(dev, "Load was not detected on output with or %d\n", or);

 	return status;
 }

 static void
 nv50_dac_dpms(struct drm_encoder *encoder, int mode)
 {
 	struct drm_device *dev = encoder->dev;
 	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
 	uint32_t val;
 	int or = nv_encoder->or;

 	NV_DEBUG(dev, "or %d mode %d\n", or, mode);

 	/* wait for it to be done */
 	if (!nv_wait(NV50_PDISPLAY_DAC_DPMS_CTRL(or),
 		     NV50_PDISPLAY_DAC_DPMS_CTRL_PENDING, 0)) {
 		NV_ERROR(dev, "timeout: DAC_DPMS_CTRL_PENDING(%d) == 0\n", or);
 		NV_ERROR(dev, "DAC_DPMS_CTRL(%d) = 0x%08x\n", or,
 			 nv_rd32(dev, NV50_PDISPLAY_DAC_DPMS_CTRL(or)));
 		return;
 	}

 	val = nv_rd32(dev, NV50_PDISPLAY_DAC_DPMS_CTRL(or)) & ~0x7F;

 	if (mode != DRM_MODE_DPMS_ON)
 		val |= NV50_PDISPLAY_DAC_DPMS_CTRL_BLANKED;

 	switch (mode) {
 	case DRM_MODE_DPMS_STANDBY:
 		val |= NV50_PDISPLAY_DAC_DPMS_CTRL_HSYNC_OFF;
 		break;
 	case DRM_MODE_DPMS_SUSPEND:
 		val |= NV50_PDISPLAY_DAC_DPMS_CTRL_VSYNC_OFF;
 		break;
 	case DRM_MODE_DPMS_OFF:
 		val |= NV50_PDISPLAY_DAC_DPMS_CTRL_OFF;
 		val |= NV50_PDISPLAY_DAC_DPMS_CTRL_HSYNC_OFF;
 		val |= NV50_PDISPLAY_DAC_DPMS_CTRL_VSYNC_OFF;
 		break;
 	default:
 		break;
 	}

 	nv_wr32(dev, NV50_PDISPLAY_DAC_DPMS_CTRL(or), val |
 		NV50_PDISPLAY_DAC_DPMS_CTRL_PENDING);
 }

 static void
 nv50_dac_save(struct drm_encoder *encoder)
 {
 	NV_ERROR(encoder->dev, "!!\n");
 }

 static void
 nv50_dac_restore(struct drm_encoder *encoder)
 {
 	NV_ERROR(encoder->dev, "!!\n");
 }

 static bool
 nv50_dac_mode_fixup(struct drm_encoder *encoder, struct drm_display_mode *mode,
 		    struct drm_display_mode *adjusted_mode)
 {
 	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
 	struct nouveau_connector *connector;

 	NV_DEBUG(encoder->dev, "or %d\n", nv_encoder->or);

 	connector = nouveau_encoder_connector_get(nv_encoder);
 	if (!connector) {
 		NV_ERROR(encoder->dev, "Encoder has no connector\n");
 		return false;
 	}

 	if (connector->scaling_mode != DRM_MODE_SCALE_NONE &&
 	     connector->native_mode) {
 		int id = adjusted_mode->base.id;
 		*adjusted_mode = *connector->native_mode;
 		adjusted_mode->base.id = id;
 	}

 	return true;
 }

 static void
 nv50_dac_prepare(struct drm_encoder *encoder)
 {
 }

 static void
 nv50_dac_commit(struct drm_encoder *encoder)
 {
 }

 static void
 nv50_dac_mode_set(struct drm_encoder *encoder, struct drm_display_mode *mode,
 		  struct drm_display_mode *adjusted_mode)
 {
 	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
 	struct drm_device *dev = encoder->dev;
 	struct drm_nouveau_private *dev_priv = dev->dev_private;
 	struct nouveau_channel *evo = dev_priv->evo;
 	struct nouveau_crtc *crtc = nouveau_crtc(encoder->crtc);
 	uint32_t mode_ctl = 0, mode_ctl2 = 0;
 	int ret;

 	NV_DEBUG(dev, "or %d\n", nv_encoder->or);

 	nv50_dac_dpms(encoder, DRM_MODE_DPMS_ON);

 	if (crtc->index == 1)
 		mode_ctl |= NV50_EVO_DAC_MODE_CTRL_CRTC1;
 	else
 		mode_ctl |= NV50_EVO_DAC_MODE_CTRL_CRTC0;

 	/* Lacking a working tv-out, this is not a 100% sure. */
 	if (nv_encoder->dcb->type == OUTPUT_ANALOG)
 		mode_ctl |= 0x40;
 	else
 	if (nv_encoder->dcb->type == OUTPUT_TV)
 		mode_ctl |= 0x100;

 	if (adjusted_mode->flags & DRM_MODE_FLAG_NHSYNC)
 		mode_ctl2 |= NV50_EVO_DAC_MODE_CTRL2_NHSYNC;

 	if (adjusted_mode->flags & DRM_MODE_FLAG_NVSYNC)
 		mode_ctl2 |= NV50_EVO_DAC_MODE_CTRL2_NVSYNC;

 	ret = RING_SPACE(evo, 3);
 	if (ret) {
 		NV_ERROR(dev, "no space while connecting DAC\n");
 		return;
 	}
 	BEGIN_RING(evo, 0, NV50_EVO_DAC(nv_encoder->or, MODE_CTRL), 2);
 	OUT_RING(evo, mode_ctl);
 	OUT_RING(evo, mode_ctl2);
 }

 static const struct drm_encoder_helper_funcs nv50_dac_helper_funcs = {
 	.dpms = nv50_dac_dpms,
 	.save = nv50_dac_save,
 	.restore = nv50_dac_restore,
 	.mode_fixup = nv50_dac_mode_fixup,
 	.prepare = nv50_dac_prepare,
 	.commit = nv50_dac_commit,
 	.mode_set = nv50_dac_mode_set,
 	.detect = nv50_dac_detect
 };

 static void
 nv50_dac_destroy(struct drm_encoder *encoder)
 {
 	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);

 	if (!encoder)
 		return;

 	NV_DEBUG(encoder->dev, "\n");

 	drm_encoder_cleanup(encoder);
 	kfree(nv_encoder);
 }

 static const struct drm_encoder_funcs nv50_dac_encoder_funcs = {
 	.destroy = nv50_dac_destroy,
 };

 int
 nv50_dac_create(struct drm_device *dev, struct dcb_entry *entry)
 {
 	struct nouveau_encoder *nv_encoder;
 	struct drm_encoder *encoder;

 	NV_DEBUG(dev, "\n");
 	NV_INFO(dev, "Detected a DAC output\n");

 	nv_encoder = kzalloc(sizeof(*nv_encoder), GFP_KERNEL);
 	if (!nv_encoder)
 		return -ENOMEM;
 	encoder = to_drm_encoder(nv_encoder);

 	nv_encoder->dcb = entry;
 	nv_encoder->or = ffs(entry->or) - 1;

 	nv_encoder->disconnect = nv50_dac_disconnect;

 	drm_encoder_init(dev, encoder, &nv50_dac_encoder_funcs,
 			 DRM_MODE_ENCODER_DAC);
 	drm_encoder_helper_add(encoder, &nv50_dac_helper_funcs);

 	encoder->possible_crtcs = entry->heads;
 	encoder->possible_clones = 0;
 	return 0;
 }
	/*
	* Copyright (C) 2008 Maarten Maathuis.
	* All Rights Reserved.
	*
	* Permission is hereby granted, free of charge, to any person obtaining
	* a copy of this software and associated documentation files (the
	* "Software"), to deal in the Software without restriction, including
	* without limitation the rights to use, copy, modify, merge, publish,
	* distribute, sublicense, and/or sell copies of the Software, and to
	* permit persons to whom the Software is furnished to do so, subject to
	* the following conditions:
	*
	* The above copyright notice and this permission notice (including the
	* next paragraph) shall be included in all copies or substantial
	* portions of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
	* IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
	* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
	* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
	* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
	*
	*/

	#include "drmP.h"
	#include "drm_crtc_helper.h"

	#define NOUVEAU_DMA_DEBUG (nouveau_reg_debug & NOUVEAU_REG_DEBUG_EVO)
	#include "nouveau_reg.h"
	#include "nouveau_drv.h"
	#include "nouveau_dma.h"
	#include "nouveau_encoder.h"
	#include "nouveau_connector.h"
	#include "nouveau_crtc.h"
	#include "nv50_display.h"

	static void
	nv50_dac_disconnect(struct nouveau_encoder *nv_encoder)
	{
	struct drm_device *dev = to_drm_encoder(nv_encoder)->dev;
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	struct nouveau_channel *evo = dev_priv->evo;
	int ret;

	NV_DEBUG(dev, "Disconnecting DAC %d\n", nv_encoder->or);

	ret = RING_SPACE(evo, 2);
	if (ret) {
	NV_ERROR(dev, "no space while disconnecting DAC\n");
	return;
	}
	BEGIN_RING(evo, 0, NV50_EVO_DAC(nv_encoder->or, MODE_CTRL), 1);
	OUT_RING(evo, 0);
	}

	static enum drm_connector_status
	nv50_dac_detect(struct drm_encoder encoder, struct drm_connector connector)
	{
	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
	struct drm_device *dev = encoder->dev;
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	enum drm_connector_status status = connector_status_disconnected;
	uint32_t dpms_state, load_pattern, load_state;
	int or = nv_encoder->or;

	nv_wr32(dev, NV50_PDISPLAY_DAC_CLK_CTRL1(or), 0x00000001);
	dpms_state = nv_rd32(dev, NV50_PDISPLAY_DAC_DPMS_CTRL(or));

	nv_wr32(dev, NV50_PDISPLAY_DAC_DPMS_CTRL(or),
	0x00150000 \| NV50_PDISPLAY_DAC_DPMS_CTRL_PENDING);
	if (!nv_wait(NV50_PDISPLAY_DAC_DPMS_CTRL(or),
	NV50_PDISPLAY_DAC_DPMS_CTRL_PENDING, 0)) {
	NV_ERROR(dev, "timeout: DAC_DPMS_CTRL_PENDING(%d) == 0\n", or);
	NV_ERROR(dev, "DAC_DPMS_CTRL(%d) = 0x%08x\n", or,
	nv_rd32(dev, NV50_PDISPLAY_DAC_DPMS_CTRL(or)));
	return status;
	}

	/* Use bios provided value if possible. */
	if (dev_priv->vbios->dactestval) {
	load_pattern = dev_priv->vbios->dactestval;
	NV_DEBUG(dev, "Using bios provided load_pattern of %d\n",
	load_pattern);
	} else {
	load_pattern = 340;
	NV_DEBUG(dev, "Using default load_pattern of %d\n",
	load_pattern);
	}

	nv_wr32(dev, NV50_PDISPLAY_DAC_LOAD_CTRL(or),
	NV50_PDISPLAY_DAC_LOAD_CTRL_ACTIVE \| load_pattern);
	mdelay(45); /* give it some time to process */
	load_state = nv_rd32(dev, NV50_PDISPLAY_DAC_LOAD_CTRL(or));

	nv_wr32(dev, NV50_PDISPLAY_DAC_LOAD_CTRL(or), 0);
	nv_wr32(dev, NV50_PDISPLAY_DAC_DPMS_CTRL(or), dpms_state \|
	NV50_PDISPLAY_DAC_DPMS_CTRL_PENDING);

	if ((load_state & NV50_PDISPLAY_DAC_LOAD_CTRL_PRESENT) ==
	NV50_PDISPLAY_DAC_LOAD_CTRL_PRESENT)
	status = connector_status_connected;

	if (status == connector_status_connected)
	NV_DEBUG(dev, "Load was detected on output with or %d\n", or);
	else
	NV_DEBUG(dev, "Load was not detected on output with or %d\n", or);

	return status;
	}

	static void
	nv50_dac_dpms(struct drm_encoder *encoder, int mode)
	{
	struct drm_device *dev = encoder->dev;
	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
	uint32_t val;
	int or = nv_encoder->or;

	NV_DEBUG(dev, "or %d mode %d\n", or, mode);

	/* wait for it to be done */
	if (!nv_wait(NV50_PDISPLAY_DAC_DPMS_CTRL(or),
	NV50_PDISPLAY_DAC_DPMS_CTRL_PENDING, 0)) {
	NV_ERROR(dev, "timeout: DAC_DPMS_CTRL_PENDING(%d) == 0\n", or);
	NV_ERROR(dev, "DAC_DPMS_CTRL(%d) = 0x%08x\n", or,
	nv_rd32(dev, NV50_PDISPLAY_DAC_DPMS_CTRL(or)));
	return;
	}

	val = nv_rd32(dev, NV50_PDISPLAY_DAC_DPMS_CTRL(or)) & ~0x7F;

	if (mode != DRM_MODE_DPMS_ON)
	val \|= NV50_PDISPLAY_DAC_DPMS_CTRL_BLANKED;

	switch (mode) {
	case DRM_MODE_DPMS_STANDBY:
	val \|= NV50_PDISPLAY_DAC_DPMS_CTRL_HSYNC_OFF;
	break;
	case DRM_MODE_DPMS_SUSPEND:
	val \|= NV50_PDISPLAY_DAC_DPMS_CTRL_VSYNC_OFF;
	break;
	case DRM_MODE_DPMS_OFF:
	val \|= NV50_PDISPLAY_DAC_DPMS_CTRL_OFF;
	val \|= NV50_PDISPLAY_DAC_DPMS_CTRL_HSYNC_OFF;
	val \|= NV50_PDISPLAY_DAC_DPMS_CTRL_VSYNC_OFF;
	break;
	default:
	break;
	}

	nv_wr32(dev, NV50_PDISPLAY_DAC_DPMS_CTRL(or), val \|
	NV50_PDISPLAY_DAC_DPMS_CTRL_PENDING);
	}

	static void
	nv50_dac_save(struct drm_encoder *encoder)
	{
	NV_ERROR(encoder->dev, "!!\n");
	}

	static void
	nv50_dac_restore(struct drm_encoder *encoder)
	{
	NV_ERROR(encoder->dev, "!!\n");
	}

	static bool
	nv50_dac_mode_fixup(struct drm_encoder encoder, struct drm_display_mode mode,
	struct drm_display_mode *adjusted_mode)
	{
	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
	struct nouveau_connector *connector;

	NV_DEBUG(encoder->dev, "or %d\n", nv_encoder->or);

	connector = nouveau_encoder_connector_get(nv_encoder);
	if (!connector) {
	NV_ERROR(encoder->dev, "Encoder has no connector\n");
	return false;
	}

	if (connector->scaling_mode != DRM_MODE_SCALE_NONE &&
	connector->native_mode) {
	int id = adjusted_mode->base.id;
	adjusted_mode = connector->native_mode;
	adjusted_mode->base.id = id;
	}

	return true;
	}

	static void
	nv50_dac_prepare(struct drm_encoder *encoder)
	{
	}

	static void
	nv50_dac_commit(struct drm_encoder *encoder)
	{
	}

	static void
	nv50_dac_mode_set(struct drm_encoder encoder, struct drm_display_mode mode,
	struct drm_display_mode *adjusted_mode)
	{
	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
	struct drm_device *dev = encoder->dev;
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	struct nouveau_channel *evo = dev_priv->evo;
	struct nouveau_crtc *crtc = nouveau_crtc(encoder->crtc);
	uint32_t mode_ctl = 0, mode_ctl2 = 0;
	int ret;

	NV_DEBUG(dev, "or %d\n", nv_encoder->or);

	nv50_dac_dpms(encoder, DRM_MODE_DPMS_ON);

	if (crtc->index == 1)
	mode_ctl \|= NV50_EVO_DAC_MODE_CTRL_CRTC1;
	else
	mode_ctl \|= NV50_EVO_DAC_MODE_CTRL_CRTC0;

	/* Lacking a working tv-out, this is not a 100% sure. */
	if (nv_encoder->dcb->type == OUTPUT_ANALOG)
	mode_ctl \|= 0x40;
	else
	if (nv_encoder->dcb->type == OUTPUT_TV)
	mode_ctl \|= 0x100;

	if (adjusted_mode->flags & DRM_MODE_FLAG_NHSYNC)
	mode_ctl2 \|= NV50_EVO_DAC_MODE_CTRL2_NHSYNC;

	if (adjusted_mode->flags & DRM_MODE_FLAG_NVSYNC)
	mode_ctl2 \|= NV50_EVO_DAC_MODE_CTRL2_NVSYNC;

	ret = RING_SPACE(evo, 3);
	if (ret) {
	NV_ERROR(dev, "no space while connecting DAC\n");
	return;
	}
	BEGIN_RING(evo, 0, NV50_EVO_DAC(nv_encoder->or, MODE_CTRL), 2);
	OUT_RING(evo, mode_ctl);
	OUT_RING(evo, mode_ctl2);
	}

	static const struct drm_encoder_helper_funcs nv50_dac_helper_funcs = {
	.dpms = nv50_dac_dpms,
	.save = nv50_dac_save,
	.restore = nv50_dac_restore,
	.mode_fixup = nv50_dac_mode_fixup,
	.prepare = nv50_dac_prepare,
	.commit = nv50_dac_commit,
	.mode_set = nv50_dac_mode_set,
	.detect = nv50_dac_detect
	};

	static void
	nv50_dac_destroy(struct drm_encoder *encoder)
	{
	struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);

	if (!encoder)
	return;

	NV_DEBUG(encoder->dev, "\n");

	drm_encoder_cleanup(encoder);
	kfree(nv_encoder);
	}

	static const struct drm_encoder_funcs nv50_dac_encoder_funcs = {
	.destroy = nv50_dac_destroy,
	};

	int
	nv50_dac_create(struct drm_device dev, struct dcb_entry entry)
	{
	struct nouveau_encoder *nv_encoder;
	struct drm_encoder *encoder;

	NV_DEBUG(dev, "\n");
	NV_INFO(dev, "Detected a DAC output\n");

	nv_encoder = kzalloc(sizeof(*nv_encoder), GFP_KERNEL);
	if (!nv_encoder)
	return -ENOMEM;
	encoder = to_drm_encoder(nv_encoder);

	nv_encoder->dcb = entry;
	nv_encoder->or = ffs(entry->or) - 1;

	nv_encoder->disconnect = nv50_dac_disconnect;

	drm_encoder_init(dev, encoder, &nv50_dac_encoder_funcs,
	DRM_MODE_ENCODER_DAC);
	drm_encoder_helper_add(encoder, &nv50_dac_helper_funcs);

	encoder->possible_crtcs = entry->heads;
	encoder->possible_clones = 0;
	return 0;
	}