/*
 * i.MX IPUv3 Graphics driver
 *
 * Copyright (C) 2011 Sascha Hauer, Pengutronix
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */
#include <linux/component.h>
#include <linux/module.h>
#include <linux/export.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <drm/drmP.h>
#include <drm/drm_atomic.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_crtc_helper.h>
#include <linux/clk.h>
#include <linux/errno.h>
#include <drm/drm_gem_cma_helper.h>
#include <drm/drm_fb_cma_helper.h>

#include <video/imx-ipu-v3.h>
#include "imx-drm.h"
#include "ipuv3-plane.h"

#define DRIVER_DESC             "i.MX IPUv3 Graphics"

struct ipu_crtc {
        struct device           *dev;
        struct drm_crtc         base;
        struct imx_drm_crtc     *imx_crtc;

        /* plane[0] is the full plane, plane[1] is the partial plane */
        struct ipu_plane        *plane[2];

        struct ipu_dc           *dc;
        struct ipu_di           *di;
        int                     irq;
};

static inline struct ipu_crtc *to_ipu_crtc(struct drm_crtc *crtc)
{
        return container_of(crtc, struct ipu_crtc, base);
}

static void ipu_crtc_enable(struct drm_crtc *crtc)
{
        struct ipu_crtc *ipu_crtc = to_ipu_crtc(crtc);
        struct ipu_soc *ipu = dev_get_drvdata(ipu_crtc->dev->parent);

        ipu_prg_enable(ipu);
        ipu_dc_enable(ipu);
        ipu_dc_enable_channel(ipu_crtc->dc);
        ipu_di_enable(ipu_crtc->di);
}

static void ipu_crtc_disable_planes(struct ipu_crtc *ipu_crtc,
                                    struct drm_crtc_state *old_crtc_state)
{
        bool disable_partial = false;
        bool disable_full = false;
        struct drm_plane *plane;

        drm_atomic_crtc_state_for_each_plane(plane, old_crtc_state) {
                if (plane == &ipu_crtc->plane[0]->base)
                        disable_full = true;
                if (&ipu_crtc->plane[1] && plane == &ipu_crtc->plane[1]->base)
                        disable_partial = true;
        }

        if (disable_partial)
                ipu_plane_disable(ipu_crtc->plane[1], true);
        if (disable_full)
                ipu_plane_disable(ipu_crtc->plane[0], false);
}

static void ipu_crtc_atomic_disable(struct drm_crtc *crtc,
                                    struct drm_crtc_state *old_crtc_state)
{
        struct ipu_crtc *ipu_crtc = to_ipu_crtc(crtc);
        struct ipu_soc *ipu = dev_get_drvdata(ipu_crtc->dev->parent);

        ipu_dc_disable_channel(ipu_crtc->dc);
        ipu_di_disable(ipu_crtc->di);
        /*
         * Planes must be disabled before DC clock is removed, as otherwise the
         * attached IDMACs will be left in undefined state, possibly hanging
         * the IPU or even system.
         */
        ipu_crtc_disable_planes(ipu_crtc, old_crtc_state);
        ipu_dc_disable(ipu);
        ipu_prg_disable(ipu);

        spin_lock_irq(&crtc->dev->event_lock);
        if (crtc->state->event) {
                drm_crtc_send_vblank_event(crtc, crtc->state->event);
                crtc->state->event = NULL;
        }
        spin_unlock_irq(&crtc->dev->event_lock);

        drm_crtc_vblank_off(crtc);
}

static void imx_drm_crtc_reset(struct drm_crtc *crtc)
{
        struct imx_crtc_state *state;

        if (crtc->state) {
                if (crtc->state->mode_blob)
                        drm_property_unreference_blob(crtc->state->mode_blob);

                state = to_imx_crtc_state(crtc->state);
                memset(state, 0, sizeof(*state));
        } else {
                state = kzalloc(sizeof(*state), GFP_KERNEL);
                if (!state)
                        return;
                crtc->state = &state->base;
        }

        state->base.crtc = crtc;
}

static struct drm_crtc_state *imx_drm_crtc_duplicate_state(struct drm_crtc *crtc)
{
        struct imx_crtc_state *state;

        state = kzalloc(sizeof(*state), GFP_KERNEL);
        if (!state)
                return NULL;

        __drm_atomic_helper_crtc_duplicate_state(crtc, &state->base);

        WARN_ON(state->base.crtc != crtc);
        state->base.crtc = crtc;

        return &state->base;
}

static void imx_drm_crtc_destroy_state(struct drm_crtc *crtc,
                                       struct drm_crtc_state *state)
{
        __drm_atomic_helper_crtc_destroy_state(state);
        kfree(to_imx_crtc_state(state));
}

static int ipu_enable_vblank(struct drm_crtc *crtc)
{
        struct ipu_crtc *ipu_crtc = to_ipu_crtc(crtc);

        enable_irq(ipu_crtc->irq);

        return 0;
}

static void ipu_disable_vblank(struct drm_crtc *crtc)
{
        struct ipu_crtc *ipu_crtc = to_ipu_crtc(crtc);

        disable_irq_nosync(ipu_crtc->irq);
}

static const struct drm_crtc_funcs ipu_crtc_funcs = {
        .set_config = drm_atomic_helper_set_config,
        .destroy = drm_crtc_cleanup,
        .page_flip = drm_atomic_helper_page_flip,
        .reset = imx_drm_crtc_reset,
        .atomic_duplicate_state = imx_drm_crtc_duplicate_state,
        .atomic_destroy_state = imx_drm_crtc_destroy_state,
        .enable_vblank = ipu_enable_vblank,
        .disable_vblank = ipu_disable_vblank,
};

static irqreturn_t ipu_irq_handler(int irq, void *dev_id)
{
        struct ipu_crtc *ipu_crtc = dev_id;

        drm_crtc_handle_vblank(&ipu_crtc->base);

        return IRQ_HANDLED;
}

static bool ipu_crtc_mode_fixup(struct drm_crtc *crtc,
                                  const struct drm_display_mode *mode,
                                  struct drm_display_mode *adjusted_mode)
{
        struct ipu_crtc *ipu_crtc = to_ipu_crtc(crtc);
        struct videomode vm;
        int ret;

        drm_display_mode_to_videomode(adjusted_mode, &vm);

        ret = ipu_di_adjust_videomode(ipu_crtc->di, &vm);
        if (ret)
                return false;

        if ((vm.vsync_len == 0) || (vm.hsync_len == 0))
                return false;

        drm_display_mode_from_videomode(&vm, adjusted_mode);

        return true;
}

static int ipu_crtc_atomic_check(struct drm_crtc *crtc,
                                 struct drm_crtc_state *state)
{
        u32 primary_plane_mask = 1 << drm_plane_index(crtc->primary);

        if (state->active && (primary_plane_mask & state->plane_mask) == 0)
                return -EINVAL;

        return 0;
}

static void ipu_crtc_atomic_begin(struct drm_crtc *crtc,
                                  struct drm_crtc_state *old_crtc_state)
{
        drm_crtc_vblank_on(crtc);

        spin_lock_irq(&crtc->dev->event_lock);
        if (crtc->state->event) {
                WARN_ON(drm_crtc_vblank_get(crtc));
                drm_crtc_arm_vblank_event(crtc, crtc->state->event);
                crtc->state->event = NULL;
        }
        spin_unlock_irq(&crtc->dev->event_lock);
}

static void ipu_crtc_mode_set_nofb(struct drm_crtc *crtc)
{
        struct drm_device *dev = crtc->dev;
        struct drm_encoder *encoder;
        struct ipu_crtc *ipu_crtc = to_ipu_crtc(crtc);
        struct drm_display_mode *mode = &crtc->state->adjusted_mode;
        struct imx_crtc_state *imx_crtc_state = to_imx_crtc_state(crtc->state);
        struct ipu_di_signal_cfg sig_cfg = {};
        unsigned long encoder_types = 0;

        dev_dbg(ipu_crtc->dev, "%s: mode->hdisplay: %d\n", __func__,
                        mode->hdisplay);
        dev_dbg(ipu_crtc->dev, "%s: mode->vdisplay: %d\n", __func__,
                        mode->vdisplay);

        list_for_each_entry(encoder, &dev->mode_config.encoder_list, head) {
                if (encoder->crtc == crtc)
                        encoder_types |= BIT(encoder->encoder_type);
        }

        dev_dbg(ipu_crtc->dev, "%s: attached to encoder types 0x%lx\n",
                __func__, encoder_types);

        /*
         * If we have DAC or LDB, then we need the IPU DI clock to be
         * the same as the LDB DI clock. For TVDAC, derive the IPU DI
         * clock from 27 MHz TVE_DI clock, but allow to divide it.
         */
        if (encoder_types & (BIT(DRM_MODE_ENCODER_DAC) |
                             BIT(DRM_MODE_ENCODER_LVDS)))
                sig_cfg.clkflags = IPU_DI_CLKMODE_SYNC | IPU_DI_CLKMODE_EXT;
        else if (encoder_types & BIT(DRM_MODE_ENCODER_TVDAC))
                sig_cfg.clkflags = IPU_DI_CLKMODE_EXT;
        else
                sig_cfg.clkflags = 0;

        sig_cfg.enable_pol = !(imx_crtc_state->bus_flags & DRM_BUS_FLAG_DE_LOW);
        /* Default to driving pixel data on negative clock edges */
        sig_cfg.clk_pol = !!(imx_crtc_state->bus_flags &
                             DRM_BUS_FLAG_PIXDATA_POSEDGE);
        sig_cfg.bus_format = imx_crtc_state->bus_format;
        sig_cfg.v_to_h_sync = 0;
        sig_cfg.hsync_pin = imx_crtc_state->di_hsync_pin;
        sig_cfg.vsync_pin = imx_crtc_state->di_vsync_pin;

        drm_display_mode_to_videomode(mode, &sig_cfg.mode);

        ipu_dc_init_sync(ipu_crtc->dc, ipu_crtc->di,
                         mode->flags & DRM_MODE_FLAG_INTERLACE,
                         imx_crtc_state->bus_format, mode->hdisplay);
        ipu_di_init_sync_panel(ipu_crtc->di, &sig_cfg);
}

static const struct drm_crtc_helper_funcs ipu_helper_funcs = {
        .mode_fixup = ipu_crtc_mode_fixup,
        .mode_set_nofb = ipu_crtc_mode_set_nofb,
        .atomic_check = ipu_crtc_atomic_check,
        .atomic_begin = ipu_crtc_atomic_begin,
        .atomic_disable = ipu_crtc_atomic_disable,
        .enable = ipu_crtc_enable,
};

static void ipu_put_resources(struct ipu_crtc *ipu_crtc)
{
        if (!IS_ERR_OR_NULL(ipu_crtc->dc))
                ipu_dc_put(ipu_crtc->dc);
        if (!IS_ERR_OR_NULL(ipu_crtc->di))
                ipu_di_put(ipu_crtc->di);
}

static int ipu_get_resources(struct ipu_crtc *ipu_crtc,
                struct ipu_client_platformdata *pdata)
{
        struct ipu_soc *ipu = dev_get_drvdata(ipu_crtc->dev->parent);
        int ret;

        ipu_crtc->dc = ipu_dc_get(ipu, pdata->dc);
        if (IS_ERR(ipu_crtc->dc)) {
                ret = PTR_ERR(ipu_crtc->dc);
                goto err_out;
        }

        ipu_crtc->di = ipu_di_get(ipu, pdata->di);
        if (IS_ERR(ipu_crtc->di)) {
                ret = PTR_ERR(ipu_crtc->di);
                goto err_out;
        }

        return 0;
err_out:
        ipu_put_resources(ipu_crtc);

        return ret;
}

static int ipu_crtc_init(struct ipu_crtc *ipu_crtc,
        struct ipu_client_platformdata *pdata, struct drm_device *drm)
{
        struct ipu_soc *ipu = dev_get_drvdata(ipu_crtc->dev->parent);
        struct drm_crtc *crtc = &ipu_crtc->base;
        int dp = -EINVAL;
        int ret;

        ret = ipu_get_resources(ipu_crtc, pdata);
        if (ret) {
                dev_err(ipu_crtc->dev, "getting resources failed with %d.\n",
                                ret);
                return ret;
        }

        if (pdata->dp >= 0)
                dp = IPU_DP_FLOW_SYNC_BG;
        ipu_crtc->plane[0] = ipu_plane_init(drm, ipu, pdata->dma[0], dp, 0,
                                            DRM_PLANE_TYPE_PRIMARY);
        if (IS_ERR(ipu_crtc->plane[0])) {
                ret = PTR_ERR(ipu_crtc->plane[0]);
                goto err_put_resources;
        }

        crtc->port = pdata->of_node;
        drm_crtc_helper_add(crtc, &ipu_helper_funcs);
        drm_crtc_init_with_planes(drm, crtc, &ipu_crtc->plane[0]->base, NULL,
                                  &ipu_crtc_funcs, NULL);

        ret = ipu_plane_get_resources(ipu_crtc->plane[0]);
        if (ret) {
                dev_err(ipu_crtc->dev, "getting plane 0 resources failed with %d.\n",
                        ret);
                goto err_put_resources;
        }

        /* If this crtc is using the DP, add an overlay plane */
        if (pdata->dp >= 0 && pdata->dma[1] > 0) {
                ipu_crtc->plane[1] = ipu_plane_init(drm, ipu, pdata->dma[1],
                                                IPU_DP_FLOW_SYNC_FG,
                                                drm_crtc_mask(&ipu_crtc->base),
                                                DRM_PLANE_TYPE_OVERLAY);
                if (IS_ERR(ipu_crtc->plane[1])) {
                        ipu_crtc->plane[1] = NULL;
                } else {
                        ret = ipu_plane_get_resources(ipu_crtc->plane[1]);
                        if (ret) {
                                dev_err(ipu_crtc->dev, "getting plane 1 "
                                        "resources failed with %d.\n", ret);
                                goto err_put_plane0_res;
                        }
                }
        }

        ipu_crtc->irq = ipu_plane_irq(ipu_crtc->plane[0]);
        ret = devm_request_irq(ipu_crtc->dev, ipu_crtc->irq, ipu_irq_handler, 0,
                        "imx_drm", ipu_crtc);
        if (ret < 0) {
                dev_err(ipu_crtc->dev, "irq request failed with %d.\n", ret);
                goto err_put_plane1_res;
        }
        /* Only enable IRQ when we actually need it to trigger work. */
        disable_irq(ipu_crtc->irq);

        return 0;

err_put_plane1_res:
        if (ipu_crtc->plane[1])
                ipu_plane_put_resources(ipu_crtc->plane[1]);
err_put_plane0_res:
        ipu_plane_put_resources(ipu_crtc->plane[0]);
err_put_resources:
        ipu_put_resources(ipu_crtc);

        return ret;
}

static int ipu_drm_bind(struct device *dev, struct device *master, void *data)
{
        struct ipu_client_platformdata *pdata = dev->platform_data;
        struct drm_device *drm = data;
        struct ipu_crtc *ipu_crtc;
        int ret;

        ipu_crtc = devm_kzalloc(dev, sizeof(*ipu_crtc), GFP_KERNEL);
        if (!ipu_crtc)
                return -ENOMEM;

        ipu_crtc->dev = dev;

        ret = ipu_crtc_init(ipu_crtc, pdata, drm);
        if (ret)
                return ret;

        dev_set_drvdata(dev, ipu_crtc);

        return 0;
}

static void ipu_drm_unbind(struct device *dev, struct device *master,
        void *data)
{
        struct ipu_crtc *ipu_crtc = dev_get_drvdata(dev);

        ipu_put_resources(ipu_crtc);
        if (ipu_crtc->plane[1])
                ipu_plane_put_resources(ipu_crtc->plane[1]);
        ipu_plane_put_resources(ipu_crtc->plane[0]);
}

static const struct component_ops ipu_crtc_ops = {
        .bind = ipu_drm_bind,
        .unbind = ipu_drm_unbind,
};

static int ipu_drm_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        int ret;

        if (!dev->platform_data)
                return -EINVAL;

        ret = dma_set_coherent_mask(dev, DMA_BIT_MASK(32));
        if (ret)
                return ret;

        return component_add(dev, &ipu_crtc_ops);
}

static int ipu_drm_remove(struct platform_device *pdev)
{
        component_del(&pdev->dev, &ipu_crtc_ops);
        return 0;
}

struct platform_driver ipu_drm_driver = {
        .driver = {
                .name = "imx-ipuv3-crtc",
        },
        .probe = ipu_drm_probe,
        .remove = ipu_drm_remove,
};