/*
 * Copyright © 2006-2007 Intel Corporation
 *
 * 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.
 *
 * Authors:
 *      Eric Anholt <eric@anholt.net>
 */

#include <linux/i2c.h>
#include <linux/slab.h>
#include "drmP.h"
#include "drm.h"
#include "drm_crtc.h"
#include "drm_crtc_helper.h"
#include "drm_edid.h"
#include "intel_drv.h"
#include "i915_drm.h"
#include "i915_drv.h"

/* Here's the desired hotplug mode */
#define ADPA_HOTPLUG_BITS (ADPA_CRT_HOTPLUG_PERIOD_128 |                \
                           ADPA_CRT_HOTPLUG_WARMUP_10MS |               \
                           ADPA_CRT_HOTPLUG_SAMPLE_4S |                 \
                           ADPA_CRT_HOTPLUG_VOLTAGE_50 |                \
                           ADPA_CRT_HOTPLUG_VOLREF_325MV |              \
                           ADPA_CRT_HOTPLUG_ENABLE)

struct intel_crt {
        struct intel_encoder base;
        bool force_hotplug_required;
};

static struct intel_crt *intel_attached_crt(struct drm_connector *connector)
{
        return container_of(intel_attached_encoder(connector),
                            struct intel_crt, base);
}

static void intel_crt_dpms(struct drm_encoder *encoder, int mode)
{
        struct drm_device *dev = encoder->dev;
        struct drm_i915_private *dev_priv = dev->dev_private;
        u32 temp, reg;

        if (HAS_PCH_SPLIT(dev))
                reg = PCH_ADPA;
        else
                reg = ADPA;

        temp = I915_READ(reg);
        temp &= ~(ADPA_HSYNC_CNTL_DISABLE | ADPA_VSYNC_CNTL_DISABLE);
        temp &= ~ADPA_DAC_ENABLE;

        switch(mode) {
        case DRM_MODE_DPMS_ON:
                temp |= ADPA_DAC_ENABLE;
                break;
        case DRM_MODE_DPMS_STANDBY:
                temp |= ADPA_DAC_ENABLE | ADPA_HSYNC_CNTL_DISABLE;
                break;
        case DRM_MODE_DPMS_SUSPEND:
                temp |= ADPA_DAC_ENABLE | ADPA_VSYNC_CNTL_DISABLE;
                break;
        case DRM_MODE_DPMS_OFF:
                temp |= ADPA_HSYNC_CNTL_DISABLE | ADPA_VSYNC_CNTL_DISABLE;
                break;
        }

        I915_WRITE(reg, temp);
}

static int intel_crt_mode_valid(struct drm_connector *connector,
                                struct drm_display_mode *mode)
{
        struct drm_device *dev = connector->dev;

        int max_clock = 0;
        if (mode->flags & DRM_MODE_FLAG_DBLSCAN)
                return MODE_NO_DBLESCAN;

        if (mode->clock < 25000)
                return MODE_CLOCK_LOW;

        if (IS_GEN2(dev))
                max_clock = 350000;
        else
                max_clock = 400000;
        if (mode->clock > max_clock)
                return MODE_CLOCK_HIGH;

        return MODE_OK;
}

static bool intel_crt_mode_fixup(struct drm_encoder *encoder,
                                 struct drm_display_mode *mode,
                                 struct drm_display_mode *adjusted_mode)
{
        return true;
}

static void intel_crt_mode_set(struct drm_encoder *encoder,
                               struct drm_display_mode *mode,
                               struct drm_display_mode *adjusted_mode)
{

        struct drm_device *dev = encoder->dev;
        struct drm_crtc *crtc = encoder->crtc;
        struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
        struct drm_i915_private *dev_priv = dev->dev_private;
        int dpll_md_reg;
        u32 adpa, dpll_md;
        u32 adpa_reg;

        dpll_md_reg = DPLL_MD(intel_crtc->pipe);

        if (HAS_PCH_SPLIT(dev))
                adpa_reg = PCH_ADPA;
        else
                adpa_reg = ADPA;

        /*
         * Disable separate mode multiplier used when cloning SDVO to CRT
         * XXX this needs to be adjusted when we really are cloning
         */
        if (INTEL_INFO(dev)->gen >= 4 && !HAS_PCH_SPLIT(dev)) {
                dpll_md = I915_READ(dpll_md_reg);
                I915_WRITE(dpll_md_reg,
                           dpll_md & ~DPLL_MD_UDI_MULTIPLIER_MASK);
        }

        adpa = ADPA_HOTPLUG_BITS;
        if (adjusted_mode->flags & DRM_MODE_FLAG_PHSYNC)
                adpa |= ADPA_HSYNC_ACTIVE_HIGH;
        if (adjusted_mode->flags & DRM_MODE_FLAG_PVSYNC)
                adpa |= ADPA_VSYNC_ACTIVE_HIGH;

        if (intel_crtc->pipe == 0) {
                if (HAS_PCH_CPT(dev))
                        adpa |= PORT_TRANS_A_SEL_CPT;
                else
                        adpa |= ADPA_PIPE_A_SELECT;
        } else {
                if (HAS_PCH_CPT(dev))
                        adpa |= PORT_TRANS_B_SEL_CPT;
                else
                        adpa |= ADPA_PIPE_B_SELECT;
        }

        if (!HAS_PCH_SPLIT(dev))
                I915_WRITE(BCLRPAT(intel_crtc->pipe), 0);

        I915_WRITE(adpa_reg, adpa);
}

static bool intel_ironlake_crt_detect_hotplug(struct drm_connector *connector)
{
        struct drm_device *dev = connector->dev;
        struct intel_crt *crt = intel_attached_crt(connector);
        struct drm_i915_private *dev_priv = dev->dev_private;
        u32 adpa;
        bool ret;

        /* The first time through, trigger an explicit detection cycle */
        if (crt->force_hotplug_required) {
                bool turn_off_dac = HAS_PCH_SPLIT(dev);
                u32 save_adpa;

                crt->force_hotplug_required = 0;

                save_adpa = adpa = I915_READ(PCH_ADPA);
                DRM_DEBUG_KMS("trigger hotplug detect cycle: adpa=0x%x\n", adpa);

                adpa |= ADPA_CRT_HOTPLUG_FORCE_TRIGGER;
                if (turn_off_dac)
                        adpa &= ~ADPA_DAC_ENABLE;

                I915_WRITE(PCH_ADPA, adpa);

                if (wait_for((I915_READ(PCH_ADPA) & ADPA_CRT_HOTPLUG_FORCE_TRIGGER) == 0,
                             1000))
                        DRM_DEBUG_KMS("timed out waiting for FORCE_TRIGGER");

                if (turn_off_dac) {
                        I915_WRITE(PCH_ADPA, save_adpa);
                        POSTING_READ(PCH_ADPA);
                }
        }

        /* Check the status to see if both blue and green are on now */
        adpa = I915_READ(PCH_ADPA);
        if ((adpa & ADPA_CRT_HOTPLUG_MONITOR_MASK) != 0)
                ret = true;
        else
                ret = false;
        DRM_DEBUG_KMS("ironlake hotplug adpa=0x%x, result %d\n", adpa, ret);

        return ret;
}

/**
 * Uses CRT_HOTPLUG_EN and CRT_HOTPLUG_STAT to detect CRT presence.
 *
 * Not for i915G/i915GM
 *
 * \return true if CRT is connected.
 * \return false if CRT is disconnected.
 */
static bool intel_crt_detect_hotplug(struct drm_connector *connector)
{
        struct drm_device *dev = connector->dev;
        struct drm_i915_private *dev_priv = dev->dev_private;
        u32 hotplug_en, orig, stat;
        bool ret = false;
        int i, tries = 0;

        if (HAS_PCH_SPLIT(dev))
                return intel_ironlake_crt_detect_hotplug(connector);

        /*
         * On 4 series desktop, CRT detect sequence need to be done twice
         * to get a reliable result.
         */

        if (IS_G4X(dev) && !IS_GM45(dev))
                tries = 2;
        else
                tries = 1;
        hotplug_en = orig = I915_READ(PORT_HOTPLUG_EN);
        hotplug_en |= CRT_HOTPLUG_FORCE_DETECT;

        for (i = 0; i < tries ; i++) {
                /* turn on the FORCE_DETECT */
                I915_WRITE(PORT_HOTPLUG_EN, hotplug_en);
                /* wait for FORCE_DETECT to go off */
                if (wait_for((I915_READ(PORT_HOTPLUG_EN) &
                              CRT_HOTPLUG_FORCE_DETECT) == 0,
                             1000))
                        DRM_DEBUG_KMS("timed out waiting for FORCE_DETECT to go off");
        }

        stat = I915_READ(PORT_HOTPLUG_STAT);
        if ((stat & CRT_HOTPLUG_MONITOR_MASK) != CRT_HOTPLUG_MONITOR_NONE)
                ret = true;

        /* clear the interrupt we just generated, if any */
        I915_WRITE(PORT_HOTPLUG_STAT, CRT_HOTPLUG_INT_STATUS);

        /* and put the bits back */
        I915_WRITE(PORT_HOTPLUG_EN, orig);

        return ret;
}

static bool intel_crt_detect_ddc(struct drm_connector *connector)
{
        struct intel_crt *crt = intel_attached_crt(connector);
        struct drm_i915_private *dev_priv = crt->base.base.dev->dev_private;

        /* CRT should always be at 0, but check anyway */
        if (crt->base.type != INTEL_OUTPUT_ANALOG)
                return false;

        if (intel_ddc_probe(&crt->base, dev_priv->crt_ddc_pin)) {
                struct edid *edid;
                bool is_digital = false;

                edid = drm_get_edid(connector,
                        &dev_priv->gmbus[dev_priv->crt_ddc_pin].adapter);
                /*
                 * This may be a DVI-I connector with a shared DDC
                 * link between analog and digital outputs, so we
                 * have to check the EDID input spec of the attached device.
                 */
                if (edid != NULL) {
                        is_digital = edid->input & DRM_EDID_INPUT_DIGITAL;
                        connector->display_info.raw_edid = NULL;
                        kfree(edid);
                }

                if (!is_digital) {
                        DRM_DEBUG_KMS("CRT detected via DDC:0x50 [EDID]\n");
                        return true;
                }
        }

        return false;
}

static enum drm_connector_status
intel_crt_load_detect(struct drm_crtc *crtc, struct intel_crt *crt)
{
        struct drm_encoder *encoder = &crt->base.base;
        struct drm_device *dev = encoder->dev;
        struct drm_i915_private *dev_priv = dev->dev_private;
        struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
        uint32_t pipe = intel_crtc->pipe;
        uint32_t save_bclrpat;
        uint32_t save_vtotal;
        uint32_t vtotal, vactive;
        uint32_t vsample;
        uint32_t vblank, vblank_start, vblank_end;
        uint32_t dsl;
        uint32_t bclrpat_reg;
        uint32_t vtotal_reg;
        uint32_t vblank_reg;
        uint32_t vsync_reg;
        uint32_t pipeconf_reg;
        uint32_t pipe_dsl_reg;
        uint8_t st00;
        enum drm_connector_status status;

        DRM_DEBUG_KMS("starting load-detect on CRT\n");

        bclrpat_reg = BCLRPAT(pipe);
        vtotal_reg = VTOTAL(pipe);
        vblank_reg = VBLANK(pipe);
        vsync_reg = VSYNC(pipe);
        pipeconf_reg = PIPECONF(pipe);
        pipe_dsl_reg = PIPEDSL(pipe);

        save_bclrpat = I915_READ(bclrpat_reg);
        save_vtotal = I915_READ(vtotal_reg);
        vblank = I915_READ(vblank_reg);

        vtotal = ((save_vtotal >> 16) & 0xfff) + 1;
        vactive = (save_vtotal & 0x7ff) + 1;

        vblank_start = (vblank & 0xfff) + 1;
        vblank_end = ((vblank >> 16) & 0xfff) + 1;

        /* Set the border color to purple. */
        I915_WRITE(bclrpat_reg, 0x500050);

        if (!IS_GEN2(dev)) {
                uint32_t pipeconf = I915_READ(pipeconf_reg);
                I915_WRITE(pipeconf_reg, pipeconf | PIPECONF_FORCE_BORDER);
                POSTING_READ(pipeconf_reg);
                /* Wait for next Vblank to substitue
                 * border color for Color info */
                intel_wait_for_vblank(dev, pipe);
                st00 = I915_READ8(VGA_MSR_WRITE);
                status = ((st00 & (1 << 4)) != 0) ?
                        connector_status_connected :
                        connector_status_disconnected;

                I915_WRITE(pipeconf_reg, pipeconf);
        } else {
                bool restore_vblank = false;
                int count, detect;

                /*
                * If there isn't any border, add some.
                * Yes, this will flicker
                */
                if (vblank_start <= vactive && vblank_end >= vtotal) {
                        uint32_t vsync = I915_READ(vsync_reg);
                        uint32_t vsync_start = (vsync & 0xffff) + 1;

                        vblank_start = vsync_start;
                        I915_WRITE(vblank_reg,
                                   (vblank_start - 1) |
                                   ((vblank_end - 1) << 16));
                        restore_vblank = true;
                }
                /* sample in the vertical border, selecting the larger one */
                if (vblank_start - vactive >= vtotal - vblank_end)
                        vsample = (vblank_start + vactive) >> 1;
                else
                        vsample = (vtotal + vblank_end) >> 1;

                /*
                 * Wait for the border to be displayed
                 */
                while (I915_READ(pipe_dsl_reg) >= vactive)
                        ;
                while ((dsl = I915_READ(pipe_dsl_reg)) <= vsample)
                        ;
                /*
                 * Watch ST00 for an entire scanline
                 */
                detect = 0;
                count = 0;
                do {
                        count++;
                        /* Read the ST00 VGA status register */
                        st00 = I915_READ8(VGA_MSR_WRITE);
                        if (st00 & (1 << 4))
                                detect++;
                } while ((I915_READ(pipe_dsl_reg) == dsl));

                /* restore vblank if necessary */
                if (restore_vblank)
                        I915_WRITE(vblank_reg, vblank);
                /*
                 * If more than 3/4 of the scanline detected a monitor,
                 * then it is assumed to be present. This works even on i830,
                 * where there isn't any way to force the border color across
                 * the screen
                 */
                status = detect * 4 > count * 3 ?
                         connector_status_connected :
                         connector_status_disconnected;
        }

        /* Restore previous settings */
        I915_WRITE(bclrpat_reg, save_bclrpat);

        return status;
}

static enum drm_connector_status
intel_crt_detect(struct drm_connector *connector, bool force)
{
        struct drm_device *dev = connector->dev;
        struct intel_crt *crt = intel_attached_crt(connector);
        struct drm_crtc *crtc;
        int dpms_mode;
        enum drm_connector_status status;

        if (I915_HAS_HOTPLUG(dev)) {
                if (intel_crt_detect_hotplug(connector)) {
                        DRM_DEBUG_KMS("CRT detected via hotplug\n");
                        return connector_status_connected;
                } else {
                        DRM_DEBUG_KMS("CRT not detected via hotplug\n");
                        return connector_status_disconnected;
                }
        }

        if (intel_crt_detect_ddc(connector))
                return connector_status_connected;

        if (!force)
                return connector->status;

        /* for pre-945g platforms use load detect */
        crtc = crt->base.base.crtc;
        if (crtc && crtc->enabled) {
                status = intel_crt_load_detect(crtc, crt);
        } else {
                crtc = intel_get_load_detect_pipe(&crt->base, connector,
                                                  NULL, &dpms_mode);
                if (crtc) {
                        if (intel_crt_detect_ddc(connector))
                                status = connector_status_connected;
                        else
                                status = intel_crt_load_detect(crtc, crt);
                        intel_release_load_detect_pipe(&crt->base,
                                                       connector, dpms_mode);
                } else
                        status = connector_status_unknown;
        }

        return status;
}

static void intel_crt_destroy(struct drm_connector *connector)
{
        drm_sysfs_connector_remove(connector);
        drm_connector_cleanup(connector);
        kfree(connector);
}

static int intel_crt_get_modes(struct drm_connector *connector)
{
        struct drm_device *dev = connector->dev;
        struct drm_i915_private *dev_priv = dev->dev_private;
        int ret;

        ret = intel_ddc_get_modes(connector,
                                 &dev_priv->gmbus[dev_priv->crt_ddc_pin].adapter);
        if (ret || !IS_G4X(dev))
                return ret;

        /* Try to probe digital port for output in DVI-I -> VGA mode. */
        return intel_ddc_get_modes(connector,
                                   &dev_priv->gmbus[GMBUS_PORT_DPB].adapter);
}

static int intel_crt_set_property(struct drm_connector *connector,
                                  struct drm_property *property,
                                  uint64_t value)
{
        return 0;
}

static void intel_crt_reset(struct drm_connector *connector)
{
        struct drm_device *dev = connector->dev;
        struct intel_crt *crt = intel_attached_crt(connector);

        if (HAS_PCH_SPLIT(dev))
                crt->force_hotplug_required = 1;
}

/*
 * Routines for controlling stuff on the analog port
 */

static const struct drm_encoder_helper_funcs intel_crt_helper_funcs = {
        .dpms = intel_crt_dpms,
        .mode_fixup = intel_crt_mode_fixup,
        .prepare = intel_encoder_prepare,
        .commit = intel_encoder_commit,
        .mode_set = intel_crt_mode_set,
};

static const struct drm_connector_funcs intel_crt_connector_funcs = {
        .reset = intel_crt_reset,
        .dpms = drm_helper_connector_dpms,
        .detect = intel_crt_detect,
        .fill_modes = drm_helper_probe_single_connector_modes,
        .destroy = intel_crt_destroy,
        .set_property = intel_crt_set_property,
};

static const struct drm_connector_helper_funcs intel_crt_connector_helper_funcs = {
        .mode_valid = intel_crt_mode_valid,
        .get_modes = intel_crt_get_modes,
        .best_encoder = intel_best_encoder,
};

static const struct drm_encoder_funcs intel_crt_enc_funcs = {
        .destroy = intel_encoder_destroy,
};

void intel_crt_init(struct drm_device *dev)
{
        struct drm_connector *connector;
        struct intel_crt *crt;
        struct intel_connector *intel_connector;
        struct drm_i915_private *dev_priv = dev->dev_private;

        crt = kzalloc(sizeof(struct intel_crt), GFP_KERNEL);
        if (!crt)
                return;

        intel_connector = kzalloc(sizeof(struct intel_connector), GFP_KERNEL);
        if (!intel_connector) {
                kfree(crt);
                return;
        }

        connector = &intel_connector->base;
        drm_connector_init(dev, &intel_connector->base,
                           &intel_crt_connector_funcs, DRM_MODE_CONNECTOR_VGA);

        drm_encoder_init(dev, &crt->base.base, &intel_crt_enc_funcs,
                         DRM_MODE_ENCODER_DAC);

        intel_connector_attach_encoder(intel_connector, &crt->base);

        crt->base.type = INTEL_OUTPUT_ANALOG;
        crt->base.clone_mask = (1 << INTEL_SDVO_NON_TV_CLONE_BIT |
                                1 << INTEL_ANALOG_CLONE_BIT |
                                1 << INTEL_SDVO_LVDS_CLONE_BIT);
        crt->base.crtc_mask = (1 << 0) | (1 << 1);
        connector->interlace_allowed = 1;
        connector->doublescan_allowed = 0;

        drm_encoder_helper_add(&crt->base.base, &intel_crt_helper_funcs);
        drm_connector_helper_add(connector, &intel_crt_connector_helper_funcs);

        drm_sysfs_connector_add(connector);

        if (I915_HAS_HOTPLUG(dev))
                connector->polled = DRM_CONNECTOR_POLL_HPD;
        else
                connector->polled = DRM_CONNECTOR_POLL_CONNECT;

        /*
         * Configure the automatic hotplug detection stuff
         */
        crt->force_hotplug_required = 0;
        if (HAS_PCH_SPLIT(dev)) {
                u32 adpa;

                adpa = I915_READ(PCH_ADPA);
                adpa &= ~ADPA_CRT_HOTPLUG_MASK;
                adpa |= ADPA_HOTPLUG_BITS;
                I915_WRITE(PCH_ADPA, adpa);
                POSTING_READ(PCH_ADPA);

                DRM_DEBUG_KMS("pch crt adpa set to 0x%x\n", adpa);
                crt->force_hotplug_required = 1;
        }

        dev_priv->hotplug_supported_mask |= CRT_HOTPLUG_INT_STATUS;
}