/*
 * OPA362 analog video amplifier with output/power control
 *
 * Copyright (C) 2014 Golden Delicious Computers
 * Author: H. Nikolaus Schaller <hns@goldelico.com>
 *
 * based on encoder-tfp410
 *
 * Copyright (C) 2013 Texas Instruments
 * Author: Tomi Valkeinen <tomi.valkeinen@ti.com>
 *
 * 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.
 */

#include <linux/gpio.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/of_gpio.h>

#include <video/omapdss.h>

struct panel_drv_data {
        struct omap_dss_device dssdev;
        struct omap_dss_device *in;

        struct gpio_desc *enable_gpio;

        struct omap_video_timings timings;
};

#define to_panel_data(x) container_of(x, struct panel_drv_data, dssdev)

static int opa362_connect(struct omap_dss_device *dssdev,
                struct omap_dss_device *dst)
{
        struct panel_drv_data *ddata = to_panel_data(dssdev);
        struct omap_dss_device *in = ddata->in;
        int r;

        dev_dbg(dssdev->dev, "connect\n");

        if (omapdss_device_is_connected(dssdev))
                return -EBUSY;

        r = in->ops.atv->connect(in, dssdev);
        if (r)
                return r;

        dst->src = dssdev;
        dssdev->dst = dst;

        return 0;
}

static void opa362_disconnect(struct omap_dss_device *dssdev,
                struct omap_dss_device *dst)
{
        struct panel_drv_data *ddata = to_panel_data(dssdev);
        struct omap_dss_device *in = ddata->in;

        dev_dbg(dssdev->dev, "disconnect\n");

        WARN_ON(!omapdss_device_is_connected(dssdev));
        if (!omapdss_device_is_connected(dssdev))
                return;

        WARN_ON(dst != dssdev->dst);
        if (dst != dssdev->dst)
                return;

        dst->src = NULL;
        dssdev->dst = NULL;

        in->ops.atv->disconnect(in, &ddata->dssdev);
}

static int opa362_enable(struct omap_dss_device *dssdev)
{
        struct panel_drv_data *ddata = to_panel_data(dssdev);
        struct omap_dss_device *in = ddata->in;
        int r;

        dev_dbg(dssdev->dev, "enable\n");

        if (!omapdss_device_is_connected(dssdev))
                return -ENODEV;

        if (omapdss_device_is_enabled(dssdev))
                return 0;

        in->ops.atv->set_timings(in, &ddata->timings);

        r = in->ops.atv->enable(in);
        if (r)
                return r;

        if (ddata->enable_gpio)
                gpiod_set_value_cansleep(ddata->enable_gpio, 1);

        dssdev->state = OMAP_DSS_DISPLAY_ACTIVE;

        return 0;
}

static void opa362_disable(struct omap_dss_device *dssdev)
{
        struct panel_drv_data *ddata = to_panel_data(dssdev);
        struct omap_dss_device *in = ddata->in;

        dev_dbg(dssdev->dev, "disable\n");

        if (!omapdss_device_is_enabled(dssdev))
                return;

        if (ddata->enable_gpio)
                gpiod_set_value_cansleep(ddata->enable_gpio, 0);

        in->ops.atv->disable(in);

        dssdev->state = OMAP_DSS_DISPLAY_DISABLED;
}

static void opa362_set_timings(struct omap_dss_device *dssdev,
                struct omap_video_timings *timings)
{
        struct panel_drv_data *ddata = to_panel_data(dssdev);
        struct omap_dss_device *in = ddata->in;

        dev_dbg(dssdev->dev, "set_timings\n");

        ddata->timings = *timings;
        dssdev->panel.timings = *timings;

        in->ops.atv->set_timings(in, timings);
}

static void opa362_get_timings(struct omap_dss_device *dssdev,
                struct omap_video_timings *timings)
{
        struct panel_drv_data *ddata = to_panel_data(dssdev);

        dev_dbg(dssdev->dev, "get_timings\n");

        *timings = ddata->timings;
}

static int opa362_check_timings(struct omap_dss_device *dssdev,
                struct omap_video_timings *timings)
{
        struct panel_drv_data *ddata = to_panel_data(dssdev);
        struct omap_dss_device *in = ddata->in;

        dev_dbg(dssdev->dev, "check_timings\n");

        return in->ops.atv->check_timings(in, timings);
}

static void opa362_set_type(struct omap_dss_device *dssdev,
                enum omap_dss_venc_type type)
{
        /* we can only drive a COMPOSITE output */
        WARN_ON(type != OMAP_DSS_VENC_TYPE_COMPOSITE);

}

static const struct omapdss_atv_ops opa362_atv_ops = {
        .connect        = opa362_connect,
        .disconnect     = opa362_disconnect,

        .enable         = opa362_enable,
        .disable        = opa362_disable,

        .check_timings  = opa362_check_timings,
        .set_timings    = opa362_set_timings,
        .get_timings    = opa362_get_timings,

        .set_type       = opa362_set_type,
};

static int opa362_probe(struct platform_device *pdev)
{
        struct device_node *node = pdev->dev.of_node;
        struct panel_drv_data *ddata;
        struct omap_dss_device *dssdev, *in;
        struct gpio_desc *gpio;
        int r;

        dev_dbg(&pdev->dev, "probe\n");

        if (node == NULL) {
                dev_err(&pdev->dev, "Unable to find device tree\n");
                return -EINVAL;
        }

        ddata = devm_kzalloc(&pdev->dev, sizeof(*ddata), GFP_KERNEL);
        if (!ddata)
                return -ENOMEM;

        platform_set_drvdata(pdev, ddata);

        gpio = devm_gpiod_get_optional(&pdev->dev, "enable", GPIOD_OUT_LOW);
        if (IS_ERR(gpio))
                return PTR_ERR(gpio);

        ddata->enable_gpio = gpio;

        in = omapdss_of_find_source_for_first_ep(node);
        if (IS_ERR(in)) {
                dev_err(&pdev->dev, "failed to find video source\n");
                return PTR_ERR(in);
        }

        ddata->in = in;

        dssdev = &ddata->dssdev;
        dssdev->ops.atv = &opa362_atv_ops;
        dssdev->dev = &pdev->dev;
        dssdev->type = OMAP_DISPLAY_TYPE_VENC;
        dssdev->output_type = OMAP_DISPLAY_TYPE_VENC;
        dssdev->owner = THIS_MODULE;

        r = omapdss_register_output(dssdev);
        if (r) {
                dev_err(&pdev->dev, "Failed to register output\n");
                goto err_reg;
        }

        return 0;
err_reg:
        omap_dss_put_device(ddata->in);
        return r;
}

static int __exit opa362_remove(struct platform_device *pdev)
{
        struct panel_drv_data *ddata = platform_get_drvdata(pdev);
        struct omap_dss_device *dssdev = &ddata->dssdev;
        struct omap_dss_device *in = ddata->in;

        omapdss_unregister_output(&ddata->dssdev);

        WARN_ON(omapdss_device_is_enabled(dssdev));
        if (omapdss_device_is_enabled(dssdev))
                opa362_disable(dssdev);

        WARN_ON(omapdss_device_is_connected(dssdev));
        if (omapdss_device_is_connected(dssdev))
                opa362_disconnect(dssdev, dssdev->dst);

        omap_dss_put_device(in);

        return 0;
}

static const struct of_device_id opa362_of_match[] = {
        { .compatible = "omapdss,ti,opa362", },
        {},
};
MODULE_DEVICE_TABLE(of, opa362_of_match);

static struct platform_driver opa362_driver = {
        .probe  = opa362_probe,
        .remove = __exit_p(opa362_remove),
        .driver = {
                .name   = "amplifier-opa362",
                .of_match_table = opa362_of_match,
                .suppress_bind_attrs = true,
        },
};

module_platform_driver(opa362_driver);

MODULE_AUTHOR("H. Nikolaus Schaller <hns@goldelico.com>");
MODULE_DESCRIPTION("OPA362 analog video amplifier with output/power control");
MODULE_LICENSE("GPL v2");