/*
 * Copyright 2003 NVIDIA, Corporation
 * Copyright 2006 Dave Airlie
 * Copyright 2007 Maarten Maathuis
 * Copyright 2007-2009 Stuart Bennett
 *
 * 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 AUTHORS OR COPYRIGHT HOLDERS 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 <drm/drm_fourcc.h>
#include <drm/drm_modeset_helper_vtables.h>

#include "nouveau_drv.h"
#include "nouveau_reg.h"
#include "nouveau_encoder.h"
#include "nouveau_connector.h"
#include "nouveau_crtc.h"
#include "hw.h"
#include "nvreg.h"

#include <dispnv04/i2c/sil164.h>

#include <subdev/i2c.h>

#define FP_TG_CONTROL_ON  (NV_PRAMDAC_FP_TG_CONTROL_DISPEN_POS |        \
                           NV_PRAMDAC_FP_TG_CONTROL_HSYNC_POS |         \
                           NV_PRAMDAC_FP_TG_CONTROL_VSYNC_POS)
#define FP_TG_CONTROL_OFF (NV_PRAMDAC_FP_TG_CONTROL_DISPEN_DISABLE |    \
                           NV_PRAMDAC_FP_TG_CONTROL_HSYNC_DISABLE |     \
                           NV_PRAMDAC_FP_TG_CONTROL_VSYNC_DISABLE)

static inline bool is_fpc_off(uint32_t fpc)
{
        return ((fpc & (FP_TG_CONTROL_ON | FP_TG_CONTROL_OFF)) ==
                        FP_TG_CONTROL_OFF);
}

int nv04_dfp_get_bound_head(struct drm_device *dev, struct dcb_output *dcbent)
{
        /* special case of nv_read_tmds to find crtc associated with an output.
         * this does not give a correct answer for off-chip dvi, but there's no
         * use for such an answer anyway
         */
        int ramdac = (dcbent->or & DCB_OUTPUT_C) >> 2;

        NVWriteRAMDAC(dev, ramdac, NV_PRAMDAC_FP_TMDS_CONTROL,
        NV_PRAMDAC_FP_TMDS_CONTROL_WRITE_DISABLE | 0x4);
        return ((NVReadRAMDAC(dev, ramdac, NV_PRAMDAC_FP_TMDS_DATA) & 0x8) >> 3) ^ ramdac;
}

void nv04_dfp_bind_head(struct drm_device *dev, struct dcb_output *dcbent,
                        int head, bool dl)
{
        /* The BIOS scripts don't do this for us, sadly
         * Luckily we do know the values ;-)
         *
         * head < 0 indicates we wish to force a setting with the overrideval
         * (for VT restore etc.)
         */

        int ramdac = (dcbent->or & DCB_OUTPUT_C) >> 2;
        uint8_t tmds04 = 0x80;

        if (head != ramdac)
                tmds04 = 0x88;

        if (dcbent->type == DCB_OUTPUT_LVDS)
                tmds04 |= 0x01;

        nv_write_tmds(dev, dcbent->or, 0, 0x04, tmds04);

        if (dl) /* dual link */
                nv_write_tmds(dev, dcbent->or, 1, 0x04, tmds04 ^ 0x08);
}

void nv04_dfp_disable(struct drm_device *dev, int head)
{
        struct nv04_crtc_reg *crtcstate = nv04_display(dev)->mode_reg.crtc_reg;

        if (NVReadRAMDAC(dev, head, NV_PRAMDAC_FP_TG_CONTROL) &
            FP_TG_CONTROL_ON) {
                /* digital remnants must be cleaned before new crtc
                 * values programmed.  delay is time for the vga stuff
                 * to realise it's in control again
                 */
                NVWriteRAMDAC(dev, head, NV_PRAMDAC_FP_TG_CONTROL,
                              FP_TG_CONTROL_OFF);
                msleep(50);
        }
        /* don't inadvertently turn it on when state written later */
        crtcstate[head].fp_control = FP_TG_CONTROL_OFF;
        crtcstate[head].CRTC[NV_CIO_CRE_LCD__INDEX] &=
                ~NV_CIO_CRE_LCD_ROUTE_MASK;
}

void nv04_dfp_update_fp_control(struct drm_encoder *encoder, int mode)
{
        struct drm_device *dev = encoder->dev;
        struct drm_crtc *crtc;
        struct nouveau_crtc *nv_crtc;
        uint32_t *fpc;

        if (mode == DRM_MODE_DPMS_ON) {
                nv_crtc = nouveau_crtc(encoder->crtc);
                fpc = &nv04_display(dev)->mode_reg.crtc_reg[nv_crtc->index].fp_control;

                if (is_fpc_off(*fpc)) {
                        /* using saved value is ok, as (is_digital && dpms_on &&
                         * fp_control==OFF) is (at present) *only* true when
                         * fpc's most recent change was by below "off" code
                         */
                        *fpc = nv_crtc->dpms_saved_fp_control;
                }

                nv_crtc->fp_users |= 1 << nouveau_encoder(encoder)->dcb->index;
                NVWriteRAMDAC(dev, nv_crtc->index, NV_PRAMDAC_FP_TG_CONTROL, *fpc);
        } else {
                list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
                        nv_crtc = nouveau_crtc(crtc);
                        fpc = &nv04_display(dev)->mode_reg.crtc_reg[nv_crtc->index].fp_control;

                        nv_crtc->fp_users &= ~(1 << nouveau_encoder(encoder)->dcb->index);
                        if (!is_fpc_off(*fpc) && !nv_crtc->fp_users) {
                                nv_crtc->dpms_saved_fp_control = *fpc;
                                /* cut the FP output */
                                *fpc &= ~FP_TG_CONTROL_ON;
                                *fpc |= FP_TG_CONTROL_OFF;
                                NVWriteRAMDAC(dev, nv_crtc->index,
                                              NV_PRAMDAC_FP_TG_CONTROL, *fpc);
                        }
                }
        }
}

static struct drm_encoder *get_tmds_slave(struct drm_encoder *encoder)
{
        struct drm_device *dev = encoder->dev;
        struct dcb_output *dcb = nouveau_encoder(encoder)->dcb;
        struct drm_encoder *slave;

        if (dcb->type != DCB_OUTPUT_TMDS || dcb->location == DCB_LOC_ON_CHIP)
                return NULL;

        /* Some BIOSes (e.g. the one in a Quadro FX1000) report several
         * TMDS transmitters at the same I2C address, in the same I2C
         * bus. This can still work because in that case one of them is
         * always hard-wired to a reasonable configuration using straps,
         * and the other one needs to be programmed.
         *
         * I don't think there's a way to know which is which, even the
         * blob programs the one exposed via I2C for *both* heads, so
         * let's do the same.
         */
        list_for_each_entry(slave, &dev->mode_config.encoder_list, head) {
                struct dcb_output *slave_dcb = nouveau_encoder(slave)->dcb;

                if (slave_dcb->type == DCB_OUTPUT_TMDS && get_encoder_i2c_funcs(slave) &&
                    slave_dcb->tmdsconf.slave_addr == dcb->tmdsconf.slave_addr)
                        return slave;
        }

        return NULL;
}

static bool nv04_dfp_mode_fixup(struct drm_encoder *encoder,
                                const struct drm_display_mode *mode,
                                struct drm_display_mode *adjusted_mode)
{
        struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
        struct nouveau_connector *nv_connector =
                nv04_encoder_get_connector(nv_encoder);

        if (!nv_connector->native_mode ||
            nv_connector->scaling_mode == DRM_MODE_SCALE_NONE ||
            mode->hdisplay > nv_connector->native_mode->hdisplay ||
            mode->vdisplay > nv_connector->native_mode->vdisplay) {
                nv_encoder->mode = *adjusted_mode;

        } else {
                nv_encoder->mode = *nv_connector->native_mode;
                adjusted_mode->clock = nv_connector->native_mode->clock;
        }

        return true;
}

static void nv04_dfp_prepare_sel_clk(struct drm_device *dev,
                                     struct nouveau_encoder *nv_encoder, int head)
{
        struct nv04_mode_state *state = &nv04_display(dev)->mode_reg;
        uint32_t bits1618 = nv_encoder->dcb->or & DCB_OUTPUT_A ? 0x10000 : 0x40000;

        if (nv_encoder->dcb->location != DCB_LOC_ON_CHIP)
                return;

        /* SEL_CLK is only used on the primary ramdac
         * It toggles spread spectrum PLL output and sets the bindings of PLLs
         * to heads on digital outputs
         */
        if (head)
                state->sel_clk |= bits1618;
        else
                state->sel_clk &= ~bits1618;

        /* nv30:
         *      bit 0           NVClk spread spectrum on/off
         *      bit 2           MemClk spread spectrum on/off
         *      bit 4           PixClk1 spread spectrum on/off toggle
         *      bit 6           PixClk2 spread spectrum on/off toggle
         *
         * nv40 (observations from bios behaviour and mmio traces):
         *      bits 4&6        as for nv30
         *      bits 5&7        head dependent as for bits 4&6, but do not appear with 4&6;
         *                      maybe a different spread mode
         *      bits 8&10       seen on dual-link dvi outputs, purpose unknown (set by POST scripts)
         *      The logic behind turning spread spectrum on/off in the first place,
         *      and which bit-pair to use, is unclear on nv40 (for earlier cards, the fp table
         *      entry has the necessary info)
         */
        if (nv_encoder->dcb->type == DCB_OUTPUT_LVDS && nv04_display(dev)->saved_reg.sel_clk & 0xf0) {
                int shift = (nv04_display(dev)->saved_reg.sel_clk & 0x50) ? 0 : 1;

                state->sel_clk &= ~0xf0;
                state->sel_clk |= (head ? 0x40 : 0x10) << shift;
        }
}

static void nv04_dfp_prepare(struct drm_encoder *encoder)
{
        struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
        const struct drm_encoder_helper_funcs *helper = encoder->helper_private;
        struct drm_device *dev = encoder->dev;
        int head = nouveau_crtc(encoder->crtc)->index;
        struct nv04_crtc_reg *crtcstate = nv04_display(dev)->mode_reg.crtc_reg;
        uint8_t *cr_lcd = &crtcstate[head].CRTC[NV_CIO_CRE_LCD__INDEX];
        uint8_t *cr_lcd_oth = &crtcstate[head ^ 1].CRTC[NV_CIO_CRE_LCD__INDEX];

        helper->dpms(encoder, DRM_MODE_DPMS_OFF);

        nv04_dfp_prepare_sel_clk(dev, nv_encoder, head);

        *cr_lcd = (*cr_lcd & ~NV_CIO_CRE_LCD_ROUTE_MASK) | 0x3;

        if (nv_two_heads(dev)) {
                if (nv_encoder->dcb->location == DCB_LOC_ON_CHIP)
                        *cr_lcd |= head ? 0x0 : 0x8;
                else {
                        *cr_lcd |= (nv_encoder->dcb->or << 4) & 0x30;
                        if (nv_encoder->dcb->type == DCB_OUTPUT_LVDS)
                                *cr_lcd |= 0x30;
                        if ((*cr_lcd & 0x30) == (*cr_lcd_oth & 0x30)) {
                                /* avoid being connected to both crtcs */
                                *cr_lcd_oth &= ~0x30;
                                NVWriteVgaCrtc(dev, head ^ 1,
                                               NV_CIO_CRE_LCD__INDEX,
                                               *cr_lcd_oth);
                        }
                }
        }
}


static void nv04_dfp_mode_set(struct drm_encoder *encoder,
                              struct drm_display_mode *mode,
                              struct drm_display_mode *adjusted_mode)
{
        struct drm_device *dev = encoder->dev;
        struct nvif_object *device = &nouveau_drm(dev)->client.device.object;
        struct nouveau_drm *drm = nouveau_drm(dev);
        struct nouveau_crtc *nv_crtc = nouveau_crtc(encoder->crtc);
        struct nv04_crtc_reg *regp = &nv04_display(dev)->mode_reg.crtc_reg[nv_crtc->index];
        struct nv04_crtc_reg *savep = &nv04_display(dev)->saved_reg.crtc_reg[nv_crtc->index];
        struct nouveau_connector *nv_connector = nouveau_crtc_connector_get(nv_crtc);
        struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
        struct drm_display_mode *output_mode = &nv_encoder->mode;
        struct drm_connector *connector = &nv_connector->base;
        const struct drm_framebuffer *fb = encoder->crtc->primary->fb;
        uint32_t mode_ratio, panel_ratio;

        NV_DEBUG(drm, "Output mode on CRTC %d:\n", nv_crtc->index);
        drm_mode_debug_printmodeline(output_mode);

        /* Initialize the FP registers in this CRTC. */
        regp->fp_horiz_regs[FP_DISPLAY_END] = output_mode->hdisplay - 1;
        regp->fp_horiz_regs[FP_TOTAL] = output_mode->htotal - 1;
        if (!nv_gf4_disp_arch(dev) ||
            (output_mode->hsync_start - output_mode->hdisplay) >=
                                        drm->vbios.digital_min_front_porch)
                regp->fp_horiz_regs[FP_CRTC] = output_mode->hdisplay;
        else
                regp->fp_horiz_regs[FP_CRTC] = output_mode->hsync_start - drm->vbios.digital_min_front_porch - 1;
        regp->fp_horiz_regs[FP_SYNC_START] = output_mode->hsync_start - 1;
        regp->fp_horiz_regs[FP_SYNC_END] = output_mode->hsync_end - 1;
        regp->fp_horiz_regs[FP_VALID_START] = output_mode->hskew;
        regp->fp_horiz_regs[FP_VALID_END] = output_mode->hdisplay - 1;

        regp->fp_vert_regs[FP_DISPLAY_END] = output_mode->vdisplay - 1;
        regp->fp_vert_regs[FP_TOTAL] = output_mode->vtotal - 1;
        regp->fp_vert_regs[FP_CRTC] = output_mode->vtotal - 5 - 1;
        regp->fp_vert_regs[FP_SYNC_START] = output_mode->vsync_start - 1;
        regp->fp_vert_regs[FP_SYNC_END] = output_mode->vsync_end - 1;
        regp->fp_vert_regs[FP_VALID_START] = 0;
        regp->fp_vert_regs[FP_VALID_END] = output_mode->vdisplay - 1;

        /* bit26: a bit seen on some g7x, no as yet discernable purpose */
        regp->fp_control = NV_PRAMDAC_FP_TG_CONTROL_DISPEN_POS |
                           (savep->fp_control & (1 << 26 | NV_PRAMDAC_FP_TG_CONTROL_READ_PROG));
        /* Deal with vsync/hsync polarity */
        /* LVDS screens do set this, but modes with +ve syncs are very rare */
        if (output_mode->flags & DRM_MODE_FLAG_PVSYNC)
                regp->fp_control |= NV_PRAMDAC_FP_TG_CONTROL_VSYNC_POS;
        if (output_mode->flags & DRM_MODE_FLAG_PHSYNC)
                regp->fp_control |= NV_PRAMDAC_FP_TG_CONTROL_HSYNC_POS;
        /* panel scaling first, as native would get set otherwise */
        if (nv_connector->scaling_mode == DRM_MODE_SCALE_NONE ||
            nv_connector->scaling_mode == DRM_MODE_SCALE_CENTER)        /* panel handles it */
                regp->fp_control |= NV_PRAMDAC_FP_TG_CONTROL_MODE_CENTER;
        else if (adjusted_mode->hdisplay == output_mode->hdisplay &&
                 adjusted_mode->vdisplay == output_mode->vdisplay) /* native mode */
                regp->fp_control |= NV_PRAMDAC_FP_TG_CONTROL_MODE_NATIVE;
        else /* gpu needs to scale */
                regp->fp_control |= NV_PRAMDAC_FP_TG_CONTROL_MODE_SCALE;
        if (nvif_rd32(device, NV_PEXTDEV_BOOT_0) & NV_PEXTDEV_BOOT_0_STRAP_FP_IFACE_12BIT)
                regp->fp_control |= NV_PRAMDAC_FP_TG_CONTROL_WIDTH_12;
        if (nv_encoder->dcb->location != DCB_LOC_ON_CHIP &&
            output_mode->clock > 165000)
                regp->fp_control |= (2 << 24);
        if (nv_encoder->dcb->type == DCB_OUTPUT_LVDS) {
                bool duallink = false, dummy;
                if (nv_connector->edid &&
                    nv_connector->type == DCB_CONNECTOR_LVDS_SPWG) {
                        duallink = (((u8 *)nv_connector->edid)[121] == 2);
                } else {
                        nouveau_bios_parse_lvds_table(dev, output_mode->clock,
                                                      &duallink, &dummy);
                }

                if (duallink)
                        regp->fp_control |= (8 << 28);
        } else
        if (output_mode->clock > 165000)
                regp->fp_control |= (8 << 28);

        regp->fp_debug_0 = NV_PRAMDAC_FP_DEBUG_0_YWEIGHT_ROUND |
                           NV_PRAMDAC_FP_DEBUG_0_XWEIGHT_ROUND |
                           NV_PRAMDAC_FP_DEBUG_0_YINTERP_BILINEAR |
                           NV_PRAMDAC_FP_DEBUG_0_XINTERP_BILINEAR |
                           NV_RAMDAC_FP_DEBUG_0_TMDS_ENABLED |
                           NV_PRAMDAC_FP_DEBUG_0_YSCALE_ENABLE |
                           NV_PRAMDAC_FP_DEBUG_0_XSCALE_ENABLE;

        /* We want automatic scaling */
        regp->fp_debug_1 = 0;
        /* This can override HTOTAL and VTOTAL */
        regp->fp_debug_2 = 0;

        /* Use 20.12 fixed point format to avoid floats */
        mode_ratio = (1 << 12) * adjusted_mode->hdisplay / adjusted_mode->vdisplay;
        panel_ratio = (1 << 12) * output_mode->hdisplay / output_mode->vdisplay;
        /* if ratios are equal, SCALE_ASPECT will automatically (and correctly)
         * get treated the same as SCALE_FULLSCREEN */
        if (nv_connector->scaling_mode == DRM_MODE_SCALE_ASPECT &&
            mode_ratio != panel_ratio) {
                uint32_t diff, scale;
                bool divide_by_2 = nv_gf4_disp_arch(dev);

                if (mode_ratio < panel_ratio) {
                        /* vertical needs to expand to glass size (automatic)
                         * horizontal needs to be scaled at vertical scale factor
                         * to maintain aspect */

                        scale = (1 << 12) * adjusted_mode->vdisplay / output_mode->vdisplay;
                        regp->fp_debug_1 = NV_PRAMDAC_FP_DEBUG_1_XSCALE_TESTMODE_ENABLE |
                                           XLATE(scale, divide_by_2, NV_PRAMDAC_FP_DEBUG_1_XSCALE_VALUE);

                        /* restrict area of screen used, horizontally */
                        diff = output_mode->hdisplay -
                               output_mode->vdisplay * mode_ratio / (1 << 12);
                        regp->fp_horiz_regs[FP_VALID_START] += diff / 2;
                        regp->fp_horiz_regs[FP_VALID_END] -= diff / 2;
                }

                if (mode_ratio > panel_ratio) {
                        /* horizontal needs to expand to glass size (automatic)
                         * vertical needs to be scaled at horizontal scale factor
                         * to maintain aspect */

                        scale = (1 << 12) * adjusted_mode->hdisplay / output_mode->hdisplay;
                        regp->fp_debug_1 = NV_PRAMDAC_FP_DEBUG_1_YSCALE_TESTMODE_ENABLE |
                                           XLATE(scale, divide_by_2, NV_PRAMDAC_FP_DEBUG_1_YSCALE_VALUE);

                        /* restrict area of screen used, vertically */
                        diff = output_mode->vdisplay -
                               (1 << 12) * output_mode->hdisplay / mode_ratio;
                        regp->fp_vert_regs[FP_VALID_START] += diff / 2;
                        regp->fp_vert_regs[FP_VALID_END] -= diff / 2;
                }
        }

        /* Output property. */
        if ((nv_connector->dithering_mode == DITHERING_MODE_ON) ||
            (nv_connector->dithering_mode == DITHERING_MODE_AUTO &&
             fb->format->depth > connector->display_info.bpc * 3)) {
                if (drm->client.device.info.chipset == 0x11)
                        regp->dither = savep->dither | 0x00010000;
                else {
                        int i;
                        regp->dither = savep->dither | 0x00000001;
                        for (i = 0; i < 3; i++) {
                                regp->dither_regs[i] = 0xe4e4e4e4;
                                regp->dither_regs[i + 3] = 0x44444444;
                        }
                }
        } else {
                if (drm->client.device.info.chipset != 0x11) {
                        /* reset them */
                        int i;
                        for (i = 0; i < 3; i++) {
                                regp->dither_regs[i] = savep->dither_regs[i];
                                regp->dither_regs[i + 3] = savep->dither_regs[i + 3];
                        }
                }
                regp->dither = savep->dither;
        }

        regp->fp_margin_color = 0;
}

static void nv04_dfp_commit(struct drm_encoder *encoder)
{
        struct drm_device *dev = encoder->dev;
        struct nouveau_drm *drm = nouveau_drm(dev);
        const struct drm_encoder_helper_funcs *helper = encoder->helper_private;
        struct nouveau_crtc *nv_crtc = nouveau_crtc(encoder->crtc);
        struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
        struct dcb_output *dcbe = nv_encoder->dcb;
        int head = nouveau_crtc(encoder->crtc)->index;
        struct drm_encoder *slave_encoder;

        if (dcbe->type == DCB_OUTPUT_TMDS)
                run_tmds_table(dev, dcbe, head, nv_encoder->mode.clock);
        else if (dcbe->type == DCB_OUTPUT_LVDS)
                call_lvds_script(dev, dcbe, head, LVDS_RESET, nv_encoder->mode.clock);

        /* update fp_control state for any changes made by scripts,
         * so correct value is written at DPMS on */
        nv04_display(dev)->mode_reg.crtc_reg[head].fp_control =
                NVReadRAMDAC(dev, head, NV_PRAMDAC_FP_TG_CONTROL);

        /* This could use refinement for flatpanels, but it should work this way */
        if (drm->client.device.info.chipset < 0x44)
                NVWriteRAMDAC(dev, 0, NV_PRAMDAC_TEST_CONTROL + nv04_dac_output_offset(encoder), 0xf0000000);
        else
                NVWriteRAMDAC(dev, 0, NV_PRAMDAC_TEST_CONTROL + nv04_dac_output_offset(encoder), 0x00100000);

        /* Init external transmitters */
        slave_encoder = get_tmds_slave(encoder);
        if (slave_encoder)
                get_encoder_i2c_funcs(slave_encoder)->mode_set(slave_encoder,
                                                               &nv_encoder->mode,
                                                               &nv_encoder->mode);

        helper->dpms(encoder, DRM_MODE_DPMS_ON);

        NV_DEBUG(drm, "Output %s is running on CRTC %d using output %c\n",
                 nv04_encoder_get_connector(nv_encoder)->base.name,
                 nv_crtc->index, '@' + ffs(nv_encoder->dcb->or));
}

static void nv04_dfp_update_backlight(struct drm_encoder *encoder, int mode)
{
#ifdef __powerpc__
        struct drm_device *dev = encoder->dev;
        struct nvif_object *device = &nouveau_drm(dev)->client.device.object;
        struct pci_dev *pdev = to_pci_dev(dev->dev);

        /* BIOS scripts usually take care of the backlight, thanks
         * Apple for your consistency.
         */
        if (pdev->device == 0x0174 || pdev->device == 0x0179 ||
            pdev->device == 0x0189 || pdev->device == 0x0329) {
                if (mode == DRM_MODE_DPMS_ON) {
                        nvif_mask(device, NV_PBUS_DEBUG_DUALHEAD_CTL, 1 << 31, 1 << 31);
                        nvif_mask(device, NV_PCRTC_GPIO_EXT, 3, 1);
                } else {
                        nvif_mask(device, NV_PBUS_DEBUG_DUALHEAD_CTL, 1 << 31, 0);
                        nvif_mask(device, NV_PCRTC_GPIO_EXT, 3, 0);
                }
        }
#endif
}

static inline bool is_powersaving_dpms(int mode)
{
        return mode != DRM_MODE_DPMS_ON && mode != NV_DPMS_CLEARED;
}

static void nv04_lvds_dpms(struct drm_encoder *encoder, int mode)
{
        struct drm_device *dev = encoder->dev;
        struct drm_crtc *crtc = encoder->crtc;
        struct nouveau_drm *drm = nouveau_drm(dev);
        struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
        bool was_powersaving = is_powersaving_dpms(nv_encoder->last_dpms);

        if (nv_encoder->last_dpms == mode)
                return;
        nv_encoder->last_dpms = mode;

        NV_DEBUG(drm, "Setting dpms mode %d on lvds encoder (output %d)\n",
                 mode, nv_encoder->dcb->index);

        if (was_powersaving && is_powersaving_dpms(mode))
                return;

        if (nv_encoder->dcb->lvdsconf.use_power_scripts) {
                /* when removing an output, crtc may not be set, but PANEL_OFF
                 * must still be run
                 */
                int head = crtc ? nouveau_crtc(crtc)->index :
                           nv04_dfp_get_bound_head(dev, nv_encoder->dcb);

                if (mode == DRM_MODE_DPMS_ON) {
                        call_lvds_script(dev, nv_encoder->dcb, head,
                                         LVDS_PANEL_ON, nv_encoder->mode.clock);
                } else
                        /* pxclk of 0 is fine for PANEL_OFF, and for a
                         * disconnected LVDS encoder there is no native_mode
                         */
                        call_lvds_script(dev, nv_encoder->dcb, head,
                                         LVDS_PANEL_OFF, 0);
        }

        nv04_dfp_update_backlight(encoder, mode);
        nv04_dfp_update_fp_control(encoder, mode);

        if (mode == DRM_MODE_DPMS_ON)
                nv04_dfp_prepare_sel_clk(dev, nv_encoder, nouveau_crtc(crtc)->index);
        else {
                nv04_display(dev)->mode_reg.sel_clk = NVReadRAMDAC(dev, 0, NV_PRAMDAC_SEL_CLK);
                nv04_display(dev)->mode_reg.sel_clk &= ~0xf0;
        }
        NVWriteRAMDAC(dev, 0, NV_PRAMDAC_SEL_CLK, nv04_display(dev)->mode_reg.sel_clk);
}

static void nv04_tmds_dpms(struct drm_encoder *encoder, int mode)
{
        struct nouveau_drm *drm = nouveau_drm(encoder->dev);
        struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);

        if (nv_encoder->last_dpms == mode)
                return;
        nv_encoder->last_dpms = mode;

        NV_DEBUG(drm, "Setting dpms mode %d on tmds encoder (output %d)\n",
                 mode, nv_encoder->dcb->index);

        nv04_dfp_update_backlight(encoder, mode);
        nv04_dfp_update_fp_control(encoder, mode);
}

static void nv04_dfp_save(struct drm_encoder *encoder)
{
        struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
        struct drm_device *dev = encoder->dev;

        if (nv_two_heads(dev))
                nv_encoder->restore.head =
                        nv04_dfp_get_bound_head(dev, nv_encoder->dcb);
}

static void nv04_dfp_restore(struct drm_encoder *encoder)
{
        struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);
        struct drm_device *dev = encoder->dev;
        int head = nv_encoder->restore.head;

        if (nv_encoder->dcb->type == DCB_OUTPUT_LVDS) {
                struct nouveau_connector *connector =
                        nv04_encoder_get_connector(nv_encoder);

                if (connector && connector->native_mode)
                        call_lvds_script(dev, nv_encoder->dcb, head,
                                         LVDS_PANEL_ON,
                                         connector->native_mode->clock);

        } else if (nv_encoder->dcb->type == DCB_OUTPUT_TMDS) {
                int clock = nouveau_hw_pllvals_to_clk
                                        (&nv04_display(dev)->saved_reg.crtc_reg[head].pllvals);

                run_tmds_table(dev, nv_encoder->dcb, head, clock);
        }

        nv_encoder->last_dpms = NV_DPMS_CLEARED;
}

static void nv04_dfp_destroy(struct drm_encoder *encoder)
{
        struct nouveau_encoder *nv_encoder = nouveau_encoder(encoder);

        if (get_encoder_i2c_funcs(encoder))
                get_encoder_i2c_funcs(encoder)->destroy(encoder);

        drm_encoder_cleanup(encoder);
        kfree(nv_encoder);
}

static void nv04_tmds_slave_init(struct drm_encoder *encoder)
{
        struct drm_device *dev = encoder->dev;
        struct dcb_output *dcb = nouveau_encoder(encoder)->dcb;
        struct nouveau_drm *drm = nouveau_drm(dev);
        struct nvkm_i2c *i2c = nvxx_i2c(drm);
        struct nvkm_i2c_bus *bus = nvkm_i2c_bus_find(i2c, NVKM_I2C_BUS_PRI);
        struct nvkm_i2c_bus_probe info[] = {
                {
                    {
                        .type = "sil164",
                        .addr = (dcb->tmdsconf.slave_addr == 0x7 ? 0x3a : 0x38),
                        .platform_data = &(struct sil164_encoder_params) {
                            SIL164_INPUT_EDGE_RISING
                         }
                    }, 0
                },
                { }
        };
        int type;

        if (!nv_gf4_disp_arch(dev) || !bus || get_tmds_slave(encoder))
                return;

        type = nvkm_i2c_bus_probe(bus, "TMDS transmitter", info, NULL, NULL);
        if (type < 0)
                return;

        nouveau_i2c_encoder_init(dev, to_encoder_i2c(encoder),
                                 &bus->i2c, &info[type].dev);
}

static const struct drm_encoder_helper_funcs nv04_lvds_helper_funcs = {
        .dpms = nv04_lvds_dpms,
        .mode_fixup = nv04_dfp_mode_fixup,
        .prepare = nv04_dfp_prepare,
        .commit = nv04_dfp_commit,
        .mode_set = nv04_dfp_mode_set,
        .detect = NULL,
};

static const struct drm_encoder_helper_funcs nv04_tmds_helper_funcs = {
        .dpms = nv04_tmds_dpms,
        .mode_fixup = nv04_dfp_mode_fixup,
        .prepare = nv04_dfp_prepare,
        .commit = nv04_dfp_commit,
        .mode_set = nv04_dfp_mode_set,
        .detect = NULL,
};

static const struct drm_encoder_funcs nv04_dfp_funcs = {
        .destroy = nv04_dfp_destroy,
};

int
nv04_dfp_create(struct drm_connector *connector, struct dcb_output *entry)
{
        const struct drm_encoder_helper_funcs *helper;
        struct nouveau_encoder *nv_encoder = NULL;
        struct drm_encoder *encoder;
        int type;

        switch (entry->type) {
        case DCB_OUTPUT_TMDS:
                type = DRM_MODE_ENCODER_TMDS;
                helper = &nv04_tmds_helper_funcs;
                break;
        case DCB_OUTPUT_LVDS:
                type = DRM_MODE_ENCODER_LVDS;
                helper = &nv04_lvds_helper_funcs;
                break;
        default:
                return -EINVAL;
        }

        nv_encoder = kzalloc_obj(*nv_encoder);
        if (!nv_encoder)
                return -ENOMEM;

        nv_encoder->enc_save = nv04_dfp_save;
        nv_encoder->enc_restore = nv04_dfp_restore;

        encoder = to_drm_encoder(nv_encoder);

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

        drm_encoder_init(connector->dev, encoder, &nv04_dfp_funcs, type, NULL);
        drm_encoder_helper_add(encoder, helper);

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

        if (entry->type == DCB_OUTPUT_TMDS &&
            entry->location != DCB_LOC_ON_CHIP)
                nv04_tmds_slave_init(encoder);

        drm_connector_attach_encoder(connector, encoder);
        return 0;
}