/*
 * linux/drivers/video/omap2/dss/dpi.c
 *
 * Copyright (C) 2009 Nokia Corporation
 * Author: Tomi Valkeinen <tomi.valkeinen@nokia.com>
 *
 * Some code and ideas taken from drivers/video/omap/ driver
 * by Imre Deak.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#define DSS_SUBSYS_NAME "DPI"

#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/export.h>
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
#include <linux/string.h>

#include <video/omapdss.h>

#include "dss.h"
#include "dss_features.h"

static struct {
        struct regulator *vdds_dsi_reg;
        struct platform_device *dsidev;

        struct mutex lock;

        struct omap_video_timings timings;
        struct dss_lcd_mgr_config mgr_config;
        int data_lines;

        struct omap_dss_output output;
} dpi;

static struct platform_device *dpi_get_dsidev(enum omap_channel channel)
{
        /*
         * XXX we can't currently use DSI PLL for DPI with OMAP3, as the DSI PLL
         * would also be used for DISPC fclk. Meaning, when the DPI output is
         * disabled, DISPC clock will be disabled, and TV out will stop.
         */
        switch (omapdss_get_version()) {
        case OMAPDSS_VER_OMAP24xx:
        case OMAPDSS_VER_OMAP34xx_ES1:
        case OMAPDSS_VER_OMAP34xx_ES3:
        case OMAPDSS_VER_OMAP3630:
        case OMAPDSS_VER_AM35xx:
                return NULL;
        default:
                break;
        }

        switch (channel) {
        case OMAP_DSS_CHANNEL_LCD:
                return dsi_get_dsidev_from_id(0);
        case OMAP_DSS_CHANNEL_LCD2:
                return dsi_get_dsidev_from_id(1);
        default:
                return NULL;
        }
}

static enum omap_dss_clk_source dpi_get_alt_clk_src(enum omap_channel channel)
{
        switch (channel) {
        case OMAP_DSS_CHANNEL_LCD:
                return OMAP_DSS_CLK_SRC_DSI_PLL_HSDIV_DISPC;
        case OMAP_DSS_CHANNEL_LCD2:
                return OMAP_DSS_CLK_SRC_DSI2_PLL_HSDIV_DISPC;
        default:
                /* this shouldn't happen */
                WARN_ON(1);
                return OMAP_DSS_CLK_SRC_FCK;
        }
}

static int dpi_set_dsi_clk(struct omap_dss_device *dssdev,
                unsigned long pck_req, unsigned long *fck, int *lck_div,
                int *pck_div)
{
        struct omap_overlay_manager *mgr = dssdev->output->manager;
        struct dsi_clock_info dsi_cinfo;
        struct dispc_clock_info dispc_cinfo;
        int r;

        r = dsi_pll_calc_clock_div_pck(dpi.dsidev, pck_req, &dsi_cinfo,
                        &dispc_cinfo);
        if (r)
                return r;

        r = dsi_pll_set_clock_div(dpi.dsidev, &dsi_cinfo);
        if (r)
                return r;

        dss_select_lcd_clk_source(mgr->id,
                        dpi_get_alt_clk_src(mgr->id));

        dpi.mgr_config.clock_info = dispc_cinfo;

        *fck = dsi_cinfo.dsi_pll_hsdiv_dispc_clk;
        *lck_div = dispc_cinfo.lck_div;
        *pck_div = dispc_cinfo.pck_div;

        return 0;
}

static int dpi_set_dispc_clk(struct omap_dss_device *dssdev,
                unsigned long pck_req, unsigned long *fck, int *lck_div,
                int *pck_div)
{
        struct dss_clock_info dss_cinfo;
        struct dispc_clock_info dispc_cinfo;
        int r;

        r = dss_calc_clock_div(pck_req, &dss_cinfo, &dispc_cinfo);
        if (r)
                return r;

        r = dss_set_clock_div(&dss_cinfo);
        if (r)
                return r;

        dpi.mgr_config.clock_info = dispc_cinfo;

        *fck = dss_cinfo.fck;
        *lck_div = dispc_cinfo.lck_div;
        *pck_div = dispc_cinfo.pck_div;

        return 0;
}

static int dpi_set_mode(struct omap_dss_device *dssdev)
{
        struct omap_video_timings *t = &dpi.timings;
        struct omap_overlay_manager *mgr = dssdev->output->manager;
        int lck_div = 0, pck_div = 0;
        unsigned long fck = 0;
        unsigned long pck;
        int r = 0;

        if (dpi.dsidev)
                r = dpi_set_dsi_clk(dssdev, t->pixel_clock * 1000, &fck,
                                &lck_div, &pck_div);
        else
                r = dpi_set_dispc_clk(dssdev, t->pixel_clock * 1000, &fck,
                                &lck_div, &pck_div);
        if (r)
                return r;

        pck = fck / lck_div / pck_div / 1000;

        if (pck != t->pixel_clock) {
                DSSWARN("Could not find exact pixel clock. "
                                "Requested %d kHz, got %lu kHz\n",
                                t->pixel_clock, pck);

                t->pixel_clock = pck;
        }

        dss_mgr_set_timings(mgr, t);

        return 0;
}

static void dpi_config_lcd_manager(struct omap_dss_device *dssdev)
{
        struct omap_overlay_manager *mgr = dssdev->output->manager;

        dpi.mgr_config.io_pad_mode = DSS_IO_PAD_MODE_BYPASS;

        dpi.mgr_config.stallmode = false;
        dpi.mgr_config.fifohandcheck = false;

        dpi.mgr_config.video_port_width = dpi.data_lines;

        dpi.mgr_config.lcden_sig_polarity = 0;

        dss_mgr_set_lcd_config(mgr, &dpi.mgr_config);
}

int omapdss_dpi_display_enable(struct omap_dss_device *dssdev)
{
        struct omap_dss_output *out = dssdev->output;
        int r;

        mutex_lock(&dpi.lock);

        if (dss_has_feature(FEAT_DPI_USES_VDDS_DSI) && !dpi.vdds_dsi_reg) {
                DSSERR("no VDSS_DSI regulator\n");
                r = -ENODEV;
                goto err_no_reg;
        }

        if (out == NULL || out->manager == NULL) {
                DSSERR("failed to enable display: no output/manager\n");
                r = -ENODEV;
                goto err_no_out_mgr;
        }

        r = omap_dss_start_device(dssdev);
        if (r) {
                DSSERR("failed to start device\n");
                goto err_start_dev;
        }

        if (dss_has_feature(FEAT_DPI_USES_VDDS_DSI)) {
                r = regulator_enable(dpi.vdds_dsi_reg);
                if (r)
                        goto err_reg_enable;
        }

        r = dispc_runtime_get();
        if (r)
                goto err_get_dispc;

        r = dss_dpi_select_source(dssdev->channel);
        if (r)
                goto err_src_sel;

        if (dpi.dsidev) {
                r = dsi_runtime_get(dpi.dsidev);
                if (r)
                        goto err_get_dsi;

                r = dsi_pll_init(dpi.dsidev, 0, 1);
                if (r)
                        goto err_dsi_pll_init;
        }

        r = dpi_set_mode(dssdev);
        if (r)
                goto err_set_mode;

        dpi_config_lcd_manager(dssdev);

        mdelay(2);

        r = dss_mgr_enable(out->manager);
        if (r)
                goto err_mgr_enable;

        mutex_unlock(&dpi.lock);

        return 0;

err_mgr_enable:
err_set_mode:
        if (dpi.dsidev)
                dsi_pll_uninit(dpi.dsidev, true);
err_dsi_pll_init:
        if (dpi.dsidev)
                dsi_runtime_put(dpi.dsidev);
err_get_dsi:
err_src_sel:
        dispc_runtime_put();
err_get_dispc:
        if (dss_has_feature(FEAT_DPI_USES_VDDS_DSI))
                regulator_disable(dpi.vdds_dsi_reg);
err_reg_enable:
        omap_dss_stop_device(dssdev);
err_start_dev:
err_no_out_mgr:
err_no_reg:
        mutex_unlock(&dpi.lock);
        return r;
}
EXPORT_SYMBOL(omapdss_dpi_display_enable);

void omapdss_dpi_display_disable(struct omap_dss_device *dssdev)
{
        struct omap_overlay_manager *mgr = dssdev->output->manager;

        mutex_lock(&dpi.lock);

        dss_mgr_disable(mgr);

        if (dpi.dsidev) {
                dss_select_lcd_clk_source(mgr->id, OMAP_DSS_CLK_SRC_FCK);
                dsi_pll_uninit(dpi.dsidev, true);
                dsi_runtime_put(dpi.dsidev);
        }

        dispc_runtime_put();

        if (dss_has_feature(FEAT_DPI_USES_VDDS_DSI))
                regulator_disable(dpi.vdds_dsi_reg);

        omap_dss_stop_device(dssdev);

        mutex_unlock(&dpi.lock);
}
EXPORT_SYMBOL(omapdss_dpi_display_disable);

void omapdss_dpi_set_timings(struct omap_dss_device *dssdev,
                struct omap_video_timings *timings)
{
        DSSDBG("dpi_set_timings\n");

        mutex_lock(&dpi.lock);

        dpi.timings = *timings;

        mutex_unlock(&dpi.lock);
}
EXPORT_SYMBOL(omapdss_dpi_set_timings);

int dpi_check_timings(struct omap_dss_device *dssdev,
                        struct omap_video_timings *timings)
{
        int r;
        struct omap_overlay_manager *mgr = dssdev->output->manager;
        int lck_div, pck_div;
        unsigned long fck;
        unsigned long pck;
        struct dispc_clock_info dispc_cinfo;

        if (mgr && !dispc_mgr_timings_ok(mgr->id, timings))
                return -EINVAL;

        if (timings->pixel_clock == 0)
                return -EINVAL;

        if (dpi.dsidev) {
                struct dsi_clock_info dsi_cinfo;
                r = dsi_pll_calc_clock_div_pck(dpi.dsidev,
                                timings->pixel_clock * 1000,
                                &dsi_cinfo, &dispc_cinfo);

                if (r)
                        return r;

                fck = dsi_cinfo.dsi_pll_hsdiv_dispc_clk;
        } else {
                struct dss_clock_info dss_cinfo;
                r = dss_calc_clock_div(timings->pixel_clock * 1000,
                                &dss_cinfo, &dispc_cinfo);

                if (r)
                        return r;

                fck = dss_cinfo.fck;
        }

        lck_div = dispc_cinfo.lck_div;
        pck_div = dispc_cinfo.pck_div;

        pck = fck / lck_div / pck_div / 1000;

        timings->pixel_clock = pck;

        return 0;
}
EXPORT_SYMBOL(dpi_check_timings);

void omapdss_dpi_set_data_lines(struct omap_dss_device *dssdev, int data_lines)
{
        mutex_lock(&dpi.lock);

        dpi.data_lines = data_lines;

        mutex_unlock(&dpi.lock);
}
EXPORT_SYMBOL(omapdss_dpi_set_data_lines);

static int __init dpi_verify_dsi_pll(struct platform_device *dsidev)
{
        int r;

        /* do initial setup with the PLL to see if it is operational */

        r = dsi_runtime_get(dsidev);
        if (r)
                return r;

        r = dsi_pll_init(dsidev, 0, 1);
        if (r) {
                dsi_runtime_put(dsidev);
                return r;
        }

        dsi_pll_uninit(dsidev, true);
        dsi_runtime_put(dsidev);

        return 0;
}

static int __init dpi_init_display(struct omap_dss_device *dssdev)
{
        struct platform_device *dsidev;

        DSSDBG("init_display\n");

        if (dss_has_feature(FEAT_DPI_USES_VDDS_DSI) &&
                                        dpi.vdds_dsi_reg == NULL) {
                struct regulator *vdds_dsi;

                vdds_dsi = dss_get_vdds_dsi();

                if (IS_ERR(vdds_dsi)) {
                        DSSERR("can't get VDDS_DSI regulator\n");
                        return PTR_ERR(vdds_dsi);
                }

                dpi.vdds_dsi_reg = vdds_dsi;
        }

        /*
         * XXX We shouldn't need dssdev->channel for this. The dsi pll clock
         * source for DPI is SoC integration detail, not something that should
         * be configured in the dssdev
         */
        dsidev = dpi_get_dsidev(dssdev->channel);

        if (dsidev && dpi_verify_dsi_pll(dsidev)) {
                dsidev = NULL;
                DSSWARN("DSI PLL not operational\n");
        }

        if (dsidev)
                DSSDBG("using DSI PLL for DPI clock\n");

        dpi.dsidev = dsidev;

        return 0;
}

static struct omap_dss_device * __init dpi_find_dssdev(struct platform_device *pdev)
{
        struct omap_dss_board_info *pdata = pdev->dev.platform_data;
        const char *def_disp_name = omapdss_get_default_display_name();
        struct omap_dss_device *def_dssdev;
        int i;

        def_dssdev = NULL;

        for (i = 0; i < pdata->num_devices; ++i) {
                struct omap_dss_device *dssdev = pdata->devices[i];

                if (dssdev->type != OMAP_DISPLAY_TYPE_DPI)
                        continue;

                if (def_dssdev == NULL)
                        def_dssdev = dssdev;

                if (def_disp_name != NULL &&
                                strcmp(dssdev->name, def_disp_name) == 0) {
                        def_dssdev = dssdev;
                        break;
                }
        }

        return def_dssdev;
}

static void __init dpi_probe_pdata(struct platform_device *dpidev)
{
        struct omap_dss_device *plat_dssdev;
        struct omap_dss_device *dssdev;
        int r;

        plat_dssdev = dpi_find_dssdev(dpidev);

        if (!plat_dssdev)
                return;

        dssdev = dss_alloc_and_init_device(&dpidev->dev);
        if (!dssdev)
                return;

        dss_copy_device_pdata(dssdev, plat_dssdev);

        r = dpi_init_display(dssdev);
        if (r) {
                DSSERR("device %s init failed: %d\n", dssdev->name, r);
                dss_put_device(dssdev);
                return;
        }

        r = omapdss_output_set_device(&dpi.output, dssdev);
        if (r) {
                DSSERR("failed to connect output to new device: %s\n",
                                dssdev->name);
                dss_put_device(dssdev);
                return;
        }

        r = dss_add_device(dssdev);
        if (r) {
                DSSERR("device %s register failed: %d\n", dssdev->name, r);
                omapdss_output_unset_device(&dpi.output);
                dss_put_device(dssdev);
                return;
        }
}

static void __init dpi_init_output(struct platform_device *pdev)
{
        struct omap_dss_output *out = &dpi.output;

        out->pdev = pdev;
        out->id = OMAP_DSS_OUTPUT_DPI;
        out->type = OMAP_DISPLAY_TYPE_DPI;

        dss_register_output(out);
}

static void __exit dpi_uninit_output(struct platform_device *pdev)
{
        struct omap_dss_output *out = &dpi.output;

        dss_unregister_output(out);
}

static int __init omap_dpi_probe(struct platform_device *pdev)
{
        mutex_init(&dpi.lock);

        dpi_init_output(pdev);

        dpi_probe_pdata(pdev);

        return 0;
}

static int __exit omap_dpi_remove(struct platform_device *pdev)
{
        dss_unregister_child_devices(&pdev->dev);

        dpi_uninit_output(pdev);

        return 0;
}

static struct platform_driver omap_dpi_driver = {
        .remove         = __exit_p(omap_dpi_remove),
        .driver         = {
                .name   = "omapdss_dpi",
                .owner  = THIS_MODULE,
        },
};

int __init dpi_init_platform_driver(void)
{
        return platform_driver_probe(&omap_dpi_driver, omap_dpi_probe);
}

void __exit dpi_uninit_platform_driver(void)
{
        platform_driver_unregister(&omap_dpi_driver);
}