/*
 * Copyright © 2016 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.
 *
 *
 */
#include <drm/drm_edid.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_dp_dual_mode_helper.h>
#include "intel_drv.h"

/* LSPCON OUI Vendor ID(signatures) */
#define LSPCON_VENDOR_PARADE_OUI 0x001CF8
#define LSPCON_VENDOR_MCA_OUI 0x0060AD

/* AUX addresses to write MCA AVI IF */
#define LSPCON_MCA_AVI_IF_WRITE_OFFSET 0x5C0
#define LSPCON_MCA_AVI_IF_CTRL 0x5DF
#define  LSPCON_MCA_AVI_IF_KICKOFF (1 << 0)
#define  LSPCON_MCA_AVI_IF_HANDLED (1 << 1)

/* AUX addresses to write Parade AVI IF */
#define LSPCON_PARADE_AVI_IF_WRITE_OFFSET 0x516
#define LSPCON_PARADE_AVI_IF_CTRL 0x51E
#define  LSPCON_PARADE_AVI_IF_KICKOFF (1 << 7)
#define LSPCON_PARADE_AVI_IF_DATA_SIZE 32

static struct intel_dp *lspcon_to_intel_dp(struct intel_lspcon *lspcon)
{
        struct intel_digital_port *dig_port =
                container_of(lspcon, struct intel_digital_port, lspcon);

        return &dig_port->dp;
}

static const char *lspcon_mode_name(enum drm_lspcon_mode mode)
{
        switch (mode) {
        case DRM_LSPCON_MODE_PCON:
                return "PCON";
        case DRM_LSPCON_MODE_LS:
                return "LS";
        case DRM_LSPCON_MODE_INVALID:
                return "INVALID";
        default:
                MISSING_CASE(mode);
                return "INVALID";
        }
}

static bool lspcon_detect_vendor(struct intel_lspcon *lspcon)
{
        struct intel_dp *dp = lspcon_to_intel_dp(lspcon);
        struct drm_dp_dpcd_ident *ident;
        u32 vendor_oui;

        if (drm_dp_read_desc(&dp->aux, &dp->desc, drm_dp_is_branch(dp->dpcd))) {
                DRM_ERROR("Can't read description\n");
                return false;
        }

        ident = &dp->desc.ident;
        vendor_oui = (ident->oui[0] << 16) | (ident->oui[1] << 8) |
                      ident->oui[2];

        switch (vendor_oui) {
        case LSPCON_VENDOR_MCA_OUI:
                lspcon->vendor = LSPCON_VENDOR_MCA;
                DRM_DEBUG_KMS("Vendor: Mega Chips\n");
                break;

        case LSPCON_VENDOR_PARADE_OUI:
                lspcon->vendor = LSPCON_VENDOR_PARADE;
                DRM_DEBUG_KMS("Vendor: Parade Tech\n");
                break;

        default:
                DRM_ERROR("Invalid/Unknown vendor OUI\n");
                return false;
        }

        return true;
}

static enum drm_lspcon_mode lspcon_get_current_mode(struct intel_lspcon *lspcon)
{
        enum drm_lspcon_mode current_mode;
        struct i2c_adapter *adapter = &lspcon_to_intel_dp(lspcon)->aux.ddc;

        if (drm_lspcon_get_mode(adapter, &current_mode)) {
                DRM_DEBUG_KMS("Error reading LSPCON mode\n");
                return DRM_LSPCON_MODE_INVALID;
        }
        return current_mode;
}

static enum drm_lspcon_mode lspcon_wait_mode(struct intel_lspcon *lspcon,
                                             enum drm_lspcon_mode mode)
{
        enum drm_lspcon_mode current_mode;

        current_mode = lspcon_get_current_mode(lspcon);
        if (current_mode == mode)
                goto out;

        DRM_DEBUG_KMS("Waiting for LSPCON mode %s to settle\n",
                      lspcon_mode_name(mode));

        wait_for((current_mode = lspcon_get_current_mode(lspcon)) == mode, 400);
        if (current_mode != mode)
                DRM_ERROR("LSPCON mode hasn't settled\n");

out:
        DRM_DEBUG_KMS("Current LSPCON mode %s\n",
                      lspcon_mode_name(current_mode));

        return current_mode;
}

static int lspcon_change_mode(struct intel_lspcon *lspcon,
                              enum drm_lspcon_mode mode)
{
        int err;
        enum drm_lspcon_mode current_mode;
        struct i2c_adapter *adapter = &lspcon_to_intel_dp(lspcon)->aux.ddc;

        err = drm_lspcon_get_mode(adapter, &current_mode);
        if (err) {
                DRM_ERROR("Error reading LSPCON mode\n");
                return err;
        }

        if (current_mode == mode) {
                DRM_DEBUG_KMS("Current mode = desired LSPCON mode\n");
                return 0;
        }

        err = drm_lspcon_set_mode(adapter, mode);
        if (err < 0) {
                DRM_ERROR("LSPCON mode change failed\n");
                return err;
        }

        lspcon->mode = mode;
        DRM_DEBUG_KMS("LSPCON mode changed done\n");
        return 0;
}

static bool lspcon_wake_native_aux_ch(struct intel_lspcon *lspcon)
{
        u8 rev;

        if (drm_dp_dpcd_readb(&lspcon_to_intel_dp(lspcon)->aux, DP_DPCD_REV,
                              &rev) != 1) {
                DRM_DEBUG_KMS("Native AUX CH down\n");
                return false;
        }

        DRM_DEBUG_KMS("Native AUX CH up, DPCD version: %d.%d\n",
                      rev >> 4, rev & 0xf);

        return true;
}

void lspcon_ycbcr420_config(struct drm_connector *connector,
                            struct intel_crtc_state *crtc_state)
{
        const struct drm_display_info *info = &connector->display_info;
        const struct drm_display_mode *adjusted_mode =
                                        &crtc_state->base.adjusted_mode;

        if (drm_mode_is_420_only(info, adjusted_mode) &&
            connector->ycbcr_420_allowed) {
                crtc_state->port_clock /= 2;
                crtc_state->output_format = INTEL_OUTPUT_FORMAT_YCBCR444;
                crtc_state->lspcon_downsampling = true;
        }
}

static bool lspcon_probe(struct intel_lspcon *lspcon)
{
        int retry;
        enum drm_dp_dual_mode_type adaptor_type;
        struct i2c_adapter *adapter = &lspcon_to_intel_dp(lspcon)->aux.ddc;
        enum drm_lspcon_mode expected_mode;

        expected_mode = lspcon_wake_native_aux_ch(lspcon) ?
                        DRM_LSPCON_MODE_PCON : DRM_LSPCON_MODE_LS;

        /* Lets probe the adaptor and check its type */
        for (retry = 0; retry < 6; retry++) {
                if (retry)
                        usleep_range(500, 1000);

                adaptor_type = drm_dp_dual_mode_detect(adapter);
                if (adaptor_type == DRM_DP_DUAL_MODE_LSPCON)
                        break;
        }

        if (adaptor_type != DRM_DP_DUAL_MODE_LSPCON) {
                DRM_DEBUG_KMS("No LSPCON detected, found %s\n",
                               drm_dp_get_dual_mode_type_name(adaptor_type));
                return false;
        }

        /* Yay ... got a LSPCON device */
        DRM_DEBUG_KMS("LSPCON detected\n");
        lspcon->mode = lspcon_wait_mode(lspcon, expected_mode);

        /*
         * In the SW state machine, lets Put LSPCON in PCON mode only.
         * In this way, it will work with both HDMI 1.4 sinks as well as HDMI
         * 2.0 sinks.
         */
        if (lspcon->mode != DRM_LSPCON_MODE_PCON) {
                if (lspcon_change_mode(lspcon, DRM_LSPCON_MODE_PCON) < 0) {
                        DRM_ERROR("LSPCON mode change to PCON failed\n");
                        return false;
                }
        }
        return true;
}

static void lspcon_resume_in_pcon_wa(struct intel_lspcon *lspcon)
{
        struct intel_dp *intel_dp = lspcon_to_intel_dp(lspcon);
        struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
        unsigned long start = jiffies;

        while (1) {
                if (intel_digital_port_connected(&dig_port->base)) {
                        DRM_DEBUG_KMS("LSPCON recovering in PCON mode after %u ms\n",
                                      jiffies_to_msecs(jiffies - start));
                        return;
                }

                if (time_after(jiffies, start + msecs_to_jiffies(1000)))
                        break;

                usleep_range(10000, 15000);
        }

        DRM_DEBUG_KMS("LSPCON DP descriptor mismatch after resume\n");
}

static bool lspcon_parade_fw_ready(struct drm_dp_aux *aux)
{
        u8 avi_if_ctrl;
        u8 retry;
        ssize_t ret;

        /* Check if LSPCON FW is ready for data */
        for (retry = 0; retry < 5; retry++) {
                if (retry)
                        usleep_range(200, 300);

                ret = drm_dp_dpcd_read(aux, LSPCON_PARADE_AVI_IF_CTRL,
                                       &avi_if_ctrl, 1);
                if (ret < 0) {
                        DRM_ERROR("Failed to read AVI IF control\n");
                        return false;
                }

                if ((avi_if_ctrl & LSPCON_PARADE_AVI_IF_KICKOFF) == 0)
                        return true;
        }

        DRM_ERROR("Parade FW not ready to accept AVI IF\n");
        return false;
}

static bool _lspcon_parade_write_infoframe_blocks(struct drm_dp_aux *aux,
                                                  u8 *avi_buf)
{
        u8 avi_if_ctrl;
        u8 block_count = 0;
        u8 *data;
        u16 reg;
        ssize_t ret;

        while (block_count < 4) {
                if (!lspcon_parade_fw_ready(aux)) {
                        DRM_DEBUG_KMS("LSPCON FW not ready, block %d\n",
                                      block_count);
                        return false;
                }

                reg = LSPCON_PARADE_AVI_IF_WRITE_OFFSET;
                data = avi_buf + block_count * 8;
                ret = drm_dp_dpcd_write(aux, reg, data, 8);
                if (ret < 0) {
                        DRM_ERROR("Failed to write AVI IF block %d\n",
                                  block_count);
                        return false;
                }

                /*
                 * Once a block of data is written, we have to inform the FW
                 * about this by writing into avi infoframe control register:
                 * - set the kickoff bit[7] to 1
                 * - write the block no. to bits[1:0]
                 */
                reg = LSPCON_PARADE_AVI_IF_CTRL;
                avi_if_ctrl = LSPCON_PARADE_AVI_IF_KICKOFF | block_count;
                ret = drm_dp_dpcd_write(aux, reg, &avi_if_ctrl, 1);
                if (ret < 0) {
                        DRM_ERROR("Failed to update (0x%x), block %d\n",
                                  reg, block_count);
                        return false;
                }

                block_count++;
        }

        DRM_DEBUG_KMS("Wrote AVI IF blocks successfully\n");
        return true;
}

static bool _lspcon_write_avi_infoframe_parade(struct drm_dp_aux *aux,
                                               const u8 *frame,
                                               ssize_t len)
{
        u8 avi_if[LSPCON_PARADE_AVI_IF_DATA_SIZE] = {1, };

        /*
         * Parade's frames contains 32 bytes of data, divided
         * into 4 frames:
         *      Token byte (first byte of first frame, must be non-zero)
         *      HB0 to HB2       from AVI IF (3 bytes header)
         *      PB0 to PB27 from AVI IF (28 bytes data)
         * So it should look like this
         *      first block: | <token> <HB0-HB2> <DB0-DB3> |
         *      next 3 blocks: |<DB4-DB11>|<DB12-DB19>|<DB20-DB28>|
         */

        if (len > LSPCON_PARADE_AVI_IF_DATA_SIZE - 1) {
                DRM_ERROR("Invalid length of infoframes\n");
                return false;
        }

        memcpy(&avi_if[1], frame, len);

        if (!_lspcon_parade_write_infoframe_blocks(aux, avi_if)) {
                DRM_DEBUG_KMS("Failed to write infoframe blocks\n");
                return false;
        }

        return true;
}

static bool _lspcon_write_avi_infoframe_mca(struct drm_dp_aux *aux,
                                            const u8 *buffer, ssize_t len)
{
        int ret;
        u32 val = 0;
        u32 retry;
        u16 reg;
        const u8 *data = buffer;

        reg = LSPCON_MCA_AVI_IF_WRITE_OFFSET;
        while (val < len) {
                /* DPCD write for AVI IF can fail on a slow FW day, so retry */
                for (retry = 0; retry < 5; retry++) {
                        ret = drm_dp_dpcd_write(aux, reg, (void *)data, 1);
                        if (ret == 1) {
                                break;
                        } else if (retry < 4) {
                                mdelay(50);
                                continue;
                        } else {
                                DRM_ERROR("DPCD write failed at:0x%x\n", reg);
                                return false;
                        }
                }
                val++; reg++; data++;
        }

        val = 0;
        reg = LSPCON_MCA_AVI_IF_CTRL;
        ret = drm_dp_dpcd_read(aux, reg, &val, 1);
        if (ret < 0) {
                DRM_ERROR("DPCD read failed, address 0x%x\n", reg);
                return false;
        }

        /* Indicate LSPCON chip about infoframe, clear bit 1 and set bit 0 */
        val &= ~LSPCON_MCA_AVI_IF_HANDLED;
        val |= LSPCON_MCA_AVI_IF_KICKOFF;

        ret = drm_dp_dpcd_write(aux, reg, &val, 1);
        if (ret < 0) {
                DRM_ERROR("DPCD read failed, address 0x%x\n", reg);
                return false;
        }

        val = 0;
        ret = drm_dp_dpcd_read(aux, reg, &val, 1);
        if (ret < 0) {
                DRM_ERROR("DPCD read failed, address 0x%x\n", reg);
                return false;
        }

        if (val == LSPCON_MCA_AVI_IF_HANDLED)
                DRM_DEBUG_KMS("AVI IF handled by FW\n");

        return true;
}

void lspcon_write_infoframe(struct intel_encoder *encoder,
                            const struct intel_crtc_state *crtc_state,
                            unsigned int type,
                            const void *frame, ssize_t len)
{
        bool ret;
        struct intel_dp *intel_dp = enc_to_intel_dp(&encoder->base);
        struct intel_lspcon *lspcon = enc_to_intel_lspcon(&encoder->base);

        /* LSPCON only needs AVI IF */
        if (type != HDMI_INFOFRAME_TYPE_AVI)
                return;

        if (lspcon->vendor == LSPCON_VENDOR_MCA)
                ret = _lspcon_write_avi_infoframe_mca(&intel_dp->aux,
                                                      frame, len);
        else
                ret = _lspcon_write_avi_infoframe_parade(&intel_dp->aux,
                                                         frame, len);

        if (!ret) {
                DRM_ERROR("Failed to write AVI infoframes\n");
                return;
        }

        DRM_DEBUG_DRIVER("AVI infoframes updated successfully\n");
}

void lspcon_set_infoframes(struct intel_encoder *encoder,
                           bool enable,
                           const struct intel_crtc_state *crtc_state,
                           const struct drm_connector_state *conn_state)
{
        ssize_t ret;
        union hdmi_infoframe frame;
        u8 buf[VIDEO_DIP_DATA_SIZE];
        struct intel_digital_port *dig_port = enc_to_dig_port(&encoder->base);
        struct intel_lspcon *lspcon = &dig_port->lspcon;
        const struct drm_display_mode *adjusted_mode =
                &crtc_state->base.adjusted_mode;

        if (!lspcon->active) {
                DRM_ERROR("Writing infoframes while LSPCON disabled ?\n");
                return;
        }

        ret = drm_hdmi_avi_infoframe_from_display_mode(&frame.avi,
                                                       conn_state->connector,
                                                       adjusted_mode);
        if (ret < 0) {
                DRM_ERROR("couldn't fill AVI infoframe\n");
                return;
        }

        if (crtc_state->output_format == INTEL_OUTPUT_FORMAT_YCBCR444) {
                if (crtc_state->lspcon_downsampling)
                        frame.avi.colorspace = HDMI_COLORSPACE_YUV420;
                else
                        frame.avi.colorspace = HDMI_COLORSPACE_YUV444;
        } else {
                frame.avi.colorspace = HDMI_COLORSPACE_RGB;
        }

        drm_hdmi_avi_infoframe_quant_range(&frame.avi,
                                           conn_state->connector,
                                           adjusted_mode,
                                           crtc_state->limited_color_range ?
                                           HDMI_QUANTIZATION_RANGE_LIMITED :
                                           HDMI_QUANTIZATION_RANGE_FULL);

        ret = hdmi_infoframe_pack(&frame, buf, sizeof(buf));
        if (ret < 0) {
                DRM_ERROR("Failed to pack AVI IF\n");
                return;
        }

        dig_port->write_infoframe(encoder, crtc_state, HDMI_INFOFRAME_TYPE_AVI,
                                  buf, ret);
}

bool lspcon_infoframe_enabled(struct intel_encoder *encoder,
                              const struct intel_crtc_state *pipe_config)
{
        return enc_to_intel_lspcon(&encoder->base)->active;
}

void lspcon_resume(struct intel_lspcon *lspcon)
{
        enum drm_lspcon_mode expected_mode;

        if (lspcon_wake_native_aux_ch(lspcon)) {
                expected_mode = DRM_LSPCON_MODE_PCON;
                lspcon_resume_in_pcon_wa(lspcon);
        } else {
                expected_mode = DRM_LSPCON_MODE_LS;
        }

        if (lspcon_wait_mode(lspcon, expected_mode) == DRM_LSPCON_MODE_PCON)
                return;

        if (lspcon_change_mode(lspcon, DRM_LSPCON_MODE_PCON))
                DRM_ERROR("LSPCON resume failed\n");
        else
                DRM_DEBUG_KMS("LSPCON resume success\n");
}

void lspcon_wait_pcon_mode(struct intel_lspcon *lspcon)
{
        lspcon_wait_mode(lspcon, DRM_LSPCON_MODE_PCON);
}

bool lspcon_init(struct intel_digital_port *intel_dig_port)
{
        struct intel_dp *dp = &intel_dig_port->dp;
        struct intel_lspcon *lspcon = &intel_dig_port->lspcon;
        struct drm_device *dev = intel_dig_port->base.base.dev;
        struct drm_i915_private *dev_priv = to_i915(dev);
        struct drm_connector *connector = &dp->attached_connector->base;

        if (!HAS_LSPCON(dev_priv)) {
                DRM_ERROR("LSPCON is not supported on this platform\n");
                return false;
        }

        lspcon->active = false;
        lspcon->mode = DRM_LSPCON_MODE_INVALID;

        if (!lspcon_probe(lspcon)) {
                DRM_ERROR("Failed to probe lspcon\n");
                return false;
        }

        if (!intel_dp_read_dpcd(dp)) {
                DRM_ERROR("LSPCON DPCD read failed\n");
                return false;
        }

        if (!lspcon_detect_vendor(lspcon)) {
                DRM_ERROR("LSPCON vendor detection failed\n");
                return false;
        }

        connector->ycbcr_420_allowed = true;
        lspcon->active = true;
        DRM_DEBUG_KMS("Success: LSPCON init\n");
        return true;
}