// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *
 * some helper function for simple DVB cards which simply DMA the
 * complete transport stream and let the computer sort everything else
 * (i.e. we are using the software demux, ...).  Also uses vb2
 * to manage DMA buffers.
 *
 * (c) 2004 Gerd Knorr <kraxel@bytesex.org> [SUSE Labs]
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/slab.h>

#include <media/videobuf2-dvb.h>

/* ------------------------------------------------------------------ */

MODULE_AUTHOR("Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]");
MODULE_DESCRIPTION("Videobuf2 helper library for simple DVB cards");
MODULE_LICENSE("GPL");

/* ------------------------------------------------------------------ */

static int dvb_fnc(struct vb2_buffer *vb, void *priv)
{
        struct vb2_dvb *dvb = priv;

        dvb_dmx_swfilter(&dvb->demux, vb2_plane_vaddr(vb, 0),
                                      vb2_get_plane_payload(vb, 0));
        return 0;
}

static int vb2_dvb_start_feed(struct dvb_demux_feed *feed)
{
        struct dvb_demux *demux = feed->demux;
        struct vb2_dvb *dvb = demux->priv;
        int rc = 0;

        if (!demux->dmx.frontend)
                return -EINVAL;

        mutex_lock(&dvb->lock);
        dvb->nfeeds++;

        if (!dvb->dvbq.threadio) {
                rc = vb2_thread_start(&dvb->dvbq, dvb_fnc, dvb, dvb->name);
                if (rc)
                        dvb->nfeeds--;
        }
        if (!rc)
                rc = dvb->nfeeds;
        mutex_unlock(&dvb->lock);
        return rc;
}

static int vb2_dvb_stop_feed(struct dvb_demux_feed *feed)
{
        struct dvb_demux *demux = feed->demux;
        struct vb2_dvb *dvb = demux->priv;
        int err = 0;

        mutex_lock(&dvb->lock);
        dvb->nfeeds--;
        if (0 == dvb->nfeeds)
                err = vb2_thread_stop(&dvb->dvbq);
        mutex_unlock(&dvb->lock);
        return err;
}

static int vb2_dvb_register_adapter(struct vb2_dvb_frontends *fe,
                          struct module *module,
                          void *adapter_priv,
                          struct device *device,
                          struct media_device *mdev,
                          char *adapter_name,
                          short *adapter_nr,
                          int mfe_shared)
{
        int result;

        mutex_init(&fe->lock);

        /* register adapter */
        result = dvb_register_adapter(&fe->adapter, adapter_name, module,
                device, adapter_nr);
        if (result < 0) {
                pr_warn("%s: dvb_register_adapter failed (errno = %d)\n",
                       adapter_name, result);
        }
        fe->adapter.priv = adapter_priv;
        fe->adapter.mfe_shared = mfe_shared;
#ifdef CONFIG_MEDIA_CONTROLLER_DVB
        if (mdev)
                fe->adapter.mdev = mdev;
#endif
        return result;
}

static int vb2_dvb_register_frontend(struct dvb_adapter *adapter,
        struct vb2_dvb *dvb)
{
        int result;

        /* register frontend */
        result = dvb_register_frontend(adapter, dvb->frontend);
        if (result < 0) {
                pr_warn("%s: dvb_register_frontend failed (errno = %d)\n",
                       dvb->name, result);
                goto fail_frontend;
        }

        /* register demux stuff */
        dvb->demux.dmx.capabilities =
                DMX_TS_FILTERING | DMX_SECTION_FILTERING |
                DMX_MEMORY_BASED_FILTERING;
        dvb->demux.priv       = dvb;
        dvb->demux.filternum  = 256;
        dvb->demux.feednum    = 256;
        dvb->demux.start_feed = vb2_dvb_start_feed;
        dvb->demux.stop_feed  = vb2_dvb_stop_feed;
        result = dvb_dmx_init(&dvb->demux);
        if (result < 0) {
                pr_warn("%s: dvb_dmx_init failed (errno = %d)\n",
                       dvb->name, result);
                goto fail_dmx;
        }

        dvb->dmxdev.filternum    = 256;
        dvb->dmxdev.demux        = &dvb->demux.dmx;
        dvb->dmxdev.capabilities = 0;
        result = dvb_dmxdev_init(&dvb->dmxdev, adapter);

        if (result < 0) {
                pr_warn("%s: dvb_dmxdev_init failed (errno = %d)\n",
                       dvb->name, result);
                goto fail_dmxdev;
        }

        dvb->fe_hw.source = DMX_FRONTEND_0;
        result = dvb->demux.dmx.add_frontend(&dvb->demux.dmx, &dvb->fe_hw);
        if (result < 0) {
                pr_warn("%s: add_frontend failed (DMX_FRONTEND_0, errno = %d)\n",
                       dvb->name, result);
                goto fail_fe_hw;
        }

        dvb->fe_mem.source = DMX_MEMORY_FE;
        result = dvb->demux.dmx.add_frontend(&dvb->demux.dmx, &dvb->fe_mem);
        if (result < 0) {
                pr_warn("%s: add_frontend failed (DMX_MEMORY_FE, errno = %d)\n",
                       dvb->name, result);
                goto fail_fe_mem;
        }

        result = dvb->demux.dmx.connect_frontend(&dvb->demux.dmx, &dvb->fe_hw);
        if (result < 0) {
                pr_warn("%s: connect_frontend failed (errno = %d)\n",
                       dvb->name, result);
                goto fail_fe_conn;
        }

        /* register network adapter */
        result = dvb_net_init(adapter, &dvb->net, &dvb->demux.dmx);
        if (result < 0) {
                pr_warn("%s: dvb_net_init failed (errno = %d)\n",
                       dvb->name, result);
                goto fail_fe_conn;
        }
        return 0;

fail_fe_conn:
        dvb->demux.dmx.remove_frontend(&dvb->demux.dmx, &dvb->fe_mem);
fail_fe_mem:
        dvb->demux.dmx.remove_frontend(&dvb->demux.dmx, &dvb->fe_hw);
fail_fe_hw:
        dvb_dmxdev_release(&dvb->dmxdev);
fail_dmxdev:
        dvb_dmx_release(&dvb->demux);
fail_dmx:
        dvb_unregister_frontend(dvb->frontend);
fail_frontend:
        dvb_frontend_detach(dvb->frontend);
        dvb->frontend = NULL;

        return result;
}

/* ------------------------------------------------------------------ */
/* Register a single adapter and one or more frontends */
int vb2_dvb_register_bus(struct vb2_dvb_frontends *f,
                         struct module *module,
                         void *adapter_priv,
                         struct device *device,
                         struct media_device *mdev,
                         short *adapter_nr,
                         int mfe_shared)
{
        struct list_head *list, *q;
        struct vb2_dvb_frontend *fe;
        int res;

        fe = vb2_dvb_get_frontend(f, 1);
        if (!fe) {
                pr_warn("Unable to register the adapter which has no frontends\n");
                return -EINVAL;
        }

        /* Bring up the adapter */
        res = vb2_dvb_register_adapter(f, module, adapter_priv, device, mdev,
                fe->dvb.name, adapter_nr, mfe_shared);
        if (res < 0) {
                pr_warn("vb2_dvb_register_adapter failed (errno = %d)\n", res);
                return res;
        }

        /* Attach all of the frontends to the adapter */
        mutex_lock(&f->lock);
        list_for_each_safe(list, q, &f->felist) {
                fe = list_entry(list, struct vb2_dvb_frontend, felist);
                res = vb2_dvb_register_frontend(&f->adapter, &fe->dvb);
                if (res < 0) {
                        pr_warn("%s: vb2_dvb_register_frontend failed (errno = %d)\n",
                                fe->dvb.name, res);
                        goto err;
                }
                res = dvb_create_media_graph(&f->adapter, false);
                if (res < 0)
                        goto err;
        }

        mutex_unlock(&f->lock);
        return 0;

err:
        mutex_unlock(&f->lock);
        vb2_dvb_unregister_bus(f);
        return res;
}
EXPORT_SYMBOL(vb2_dvb_register_bus);

void vb2_dvb_unregister_bus(struct vb2_dvb_frontends *f)
{
        vb2_dvb_dealloc_frontends(f);

        dvb_unregister_adapter(&f->adapter);
}
EXPORT_SYMBOL(vb2_dvb_unregister_bus);

struct vb2_dvb_frontend *vb2_dvb_get_frontend(
        struct vb2_dvb_frontends *f, int id)
{
        struct list_head *list, *q;
        struct vb2_dvb_frontend *fe, *ret = NULL;

        mutex_lock(&f->lock);

        list_for_each_safe(list, q, &f->felist) {
                fe = list_entry(list, struct vb2_dvb_frontend, felist);
                if (fe->id == id) {
                        ret = fe;
                        break;
                }
        }

        mutex_unlock(&f->lock);

        return ret;
}
EXPORT_SYMBOL(vb2_dvb_get_frontend);

int vb2_dvb_find_frontend(struct vb2_dvb_frontends *f,
        struct dvb_frontend *p)
{
        struct list_head *list, *q;
        struct vb2_dvb_frontend *fe = NULL;
        int ret = 0;

        mutex_lock(&f->lock);

        list_for_each_safe(list, q, &f->felist) {
                fe = list_entry(list, struct vb2_dvb_frontend, felist);
                if (fe->dvb.frontend == p) {
                        ret = fe->id;
                        break;
                }
        }

        mutex_unlock(&f->lock);

        return ret;
}
EXPORT_SYMBOL(vb2_dvb_find_frontend);

struct vb2_dvb_frontend *vb2_dvb_alloc_frontend(
        struct vb2_dvb_frontends *f, int id)
{
        struct vb2_dvb_frontend *fe;

        fe = kzalloc_obj(struct vb2_dvb_frontend);
        if (fe == NULL)
                return NULL;

        fe->id = id;
        mutex_init(&fe->dvb.lock);

        mutex_lock(&f->lock);
        list_add_tail(&fe->felist, &f->felist);
        mutex_unlock(&f->lock);
        return fe;
}
EXPORT_SYMBOL(vb2_dvb_alloc_frontend);

void vb2_dvb_dealloc_frontends(struct vb2_dvb_frontends *f)
{
        struct list_head *list, *q;
        struct vb2_dvb_frontend *fe;

        mutex_lock(&f->lock);
        list_for_each_safe(list, q, &f->felist) {
                fe = list_entry(list, struct vb2_dvb_frontend, felist);
                if (fe->dvb.net.dvbdev) {
                        dvb_net_release(&fe->dvb.net);
                        fe->dvb.demux.dmx.remove_frontend(&fe->dvb.demux.dmx,
                                &fe->dvb.fe_mem);
                        fe->dvb.demux.dmx.remove_frontend(&fe->dvb.demux.dmx,
                                &fe->dvb.fe_hw);
                        dvb_dmxdev_release(&fe->dvb.dmxdev);
                        dvb_dmx_release(&fe->dvb.demux);
                        dvb_unregister_frontend(fe->dvb.frontend);
                }
                if (fe->dvb.frontend)
                        /* always allocated, may have been reset */
                        dvb_frontend_detach(fe->dvb.frontend);
                list_del(list); /* remove list entry */
                kfree(fe);      /* free frontend allocation */
        }
        mutex_unlock(&f->lock);
}
EXPORT_SYMBOL(vb2_dvb_dealloc_frontends);