sdi.c

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/*
 * linux/drivers/video/omap2/dss/sdi.c
 *
 * Copyright (C) 2009 Nokia Corporation
 * Author: Tomi Valkeinen <[email protected]>
 *
 * 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 "SDI"

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

#include <video/omapdss.h>
#include "dss.h"

static struct {
    bool update_enabled;
    struct regulator *vdds_sdi_reg;

    struct dss_lcd_mgr_config mgr_config;
    struct omap_video_timings timings;
    int datapairs;

    struct omap_dss_output output;
} sdi;

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

    sdi.mgr_config.io_pad_mode = DSS_IO_PAD_MODE_BYPASS;

    sdi.mgr_config.stallmode = false;
    sdi.mgr_config.fifohandcheck = false;

    sdi.mgr_config.video_port_width = 24;
    sdi.mgr_config.lcden_sig_polarity = 1;

    dss_mgr_set_lcd_config(mgr, &sdi.mgr_config);
}

int omapdss_sdi_display_enable(struct omap_dss_device *dssdev)
{
    struct omap_dss_output *out = dssdev->output;
    struct omap_video_timings *t = &sdi.timings;
    struct dss_clock_info dss_cinfo;
    struct dispc_clock_info dispc_cinfo;
    unsigned long pck;
    int r;

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

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

    r = regulator_enable(sdi.vdds_sdi_reg);
    if (r)
        goto err_reg_enable;

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

    /* 15.5.9.1.2 */
    t->data_pclk_edge = OMAPDSS_DRIVE_SIG_RISING_EDGE;
    t->sync_pclk_edge = OMAPDSS_DRIVE_SIG_RISING_EDGE;

    r = dss_calc_clock_div(t->pixel_clock * 1000, &dss_cinfo, &dispc_cinfo);
    if (r)
        goto err_calc_clock_div;

    sdi.mgr_config.clock_info = dispc_cinfo;

    pck = dss_cinfo.fck / dispc_cinfo.lck_div / dispc_cinfo.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(out->manager, t);

    r = dss_set_clock_div(&dss_cinfo);
    if (r)
        goto err_set_dss_clock_div;

    sdi_config_lcd_manager(dssdev);

    /*
     * LCLK and PCLK divisors are located in shadow registers, and we
     * normally write them to DISPC registers when enabling the output.
     * However, SDI uses pck-free as source clock for its PLL, and pck-free
     * is affected by the divisors. And as we need the PLL before enabling
     * the output, we need to write the divisors early.
     *
     * It seems just writing to the DISPC register is enough, and we don't
     * need to care about the shadow register mechanism for pck-free. The
     * exact reason for this is unknown.
     */
    dispc_mgr_set_clock_div(out->manager->id, &sdi.mgr_config.clock_info);

    dss_sdi_init(sdi.datapairs);
    r = dss_sdi_enable();
    if (r)
        goto err_sdi_enable;
    mdelay(2);

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

    return 0;

err_mgr_enable:
    dss_sdi_disable();
err_sdi_enable:
err_set_dss_clock_div:
err_calc_clock_div:
    dispc_runtime_put();
err_get_dispc:
    regulator_disable(sdi.vdds_sdi_reg);
err_reg_enable:
    omap_dss_stop_device(dssdev);
err_start_dev:
    return r;
}
EXPORT_SYMBOL(omapdss_sdi_display_enable);

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

    dss_mgr_disable(mgr);

    dss_sdi_disable();

    dispc_runtime_put();

    regulator_disable(sdi.vdds_sdi_reg);

    omap_dss_stop_device(dssdev);
}
EXPORT_SYMBOL(omapdss_sdi_display_disable);

void omapdss_sdi_set_timings(struct omap_dss_device *dssdev,
        struct omap_video_timings *timings)
{
    sdi.timings = *timings;
}
EXPORT_SYMBOL(omapdss_sdi_set_timings);

void omapdss_sdi_set_datapairs(struct omap_dss_device *dssdev, int datapairs)
{
    sdi.datapairs = datapairs;
}
EXPORT_SYMBOL(omapdss_sdi_set_datapairs);

static int __init sdi_init_display(struct omap_dss_device *dssdev)
{
    DSSDBG("SDI init\n");

    if (sdi.vdds_sdi_reg == NULL) {
        struct regulator *vdds_sdi;

        vdds_sdi = dss_get_vdds_sdi();

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

        sdi.vdds_sdi_reg = vdds_sdi;
    }

    return 0;
}

static struct omap_dss_device * __init sdi_find_dssdev(struct platform_device *pdev)
{
    struct omap_dss_board_info *pdata = pdev->dev.platform_data;
    const char *def_disp_name = dss_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_SDI)
            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 sdi_probe_pdata(struct platform_device *sdidev)
{
    struct omap_dss_device *plat_dssdev;
    struct omap_dss_device *dssdev;
    int r;

    plat_dssdev = sdi_find_dssdev(sdidev);

    if (!plat_dssdev)
        return;

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

    dss_copy_device_pdata(dssdev, plat_dssdev);

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

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

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

    out->pdev = pdev;
    out->id = OMAP_DSS_OUTPUT_SDI;
    out->type = OMAP_DISPLAY_TYPE_SDI;

    dss_register_output(out);
}

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

    dss_unregister_output(out);
}

static int __init omap_sdi_probe(struct platform_device *pdev)
{
    sdi_init_output(pdev);

    sdi_probe_pdata(pdev);

    return 0;
}

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

    sdi_uninit_output(pdev);

    return 0;
}

static struct platform_driver omap_sdi_driver = {
    .remove         = __exit_p(omap_sdi_remove),
    .driver         = {
        .name   = "omapdss_sdi",
        .owner  = THIS_MODULE,
    },
};

int __init sdi_init_platform_driver(void)
{
    return platform_driver_probe(&omap_sdi_driver, omap_sdi_probe);
}

void __exit sdi_uninit_platform_driver(void)
{
    platform_driver_unregister(&omap_sdi_driver);
}