[media] media: davinci: vpif: display: add V4L2-async support

Add support for asynchronous subdevice probing, using the v4l2-async API.
The legacy synchronous mode is still supported too, which allows to
gradually update drivers and platforms.

Signed-off-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Hans Verkuil <hans.verkuil@cisco.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Sakari Ailus <sakari.ailus@iki.fi>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

3 files changed, 132 insertions, 83 deletions

diff --git a/drivers/media/platform/davinci/vpif_display.c b/drivers/media/platform/davinci/vpif_display.c
index e6e573650250..c2ff06745fdc 100644
--- a/drivers/media/platform/davinci/vpif_display.c
+++ b/drivers/media/platform/davinci/vpif_display.c
@@ -1618,6 +1618,102 @@ vpif_init_free_channel_objects:
         return err;
 }
 
+static int vpif_async_bound(struct v4l2_async_notifier *notifier,
+                            struct v4l2_subdev *subdev,
+                            struct v4l2_async_subdev *asd)
+{
+        int i;
+
+        for (i = 0; i < vpif_obj.config->subdev_count; i++)
+                if (!strcmp(vpif_obj.config->subdevinfo[i].name,
+                            subdev->name)) {
+                        vpif_obj.sd[i] = subdev;
+                        vpif_obj.sd[i]->grp_id = 1 << i;
+                        return 0;
+                }
+
+        return -EINVAL;
+}
+
+static int vpif_probe_complete(void)
+{
+        struct common_obj *common;
+        struct channel_obj *ch;
+        int j, err, k;
+
+        for (j = 0; j < VPIF_DISPLAY_MAX_DEVICES; j++) {
+                ch = vpif_obj.dev[j];
+                /* Initialize field of the channel objects */
+                atomic_set(&ch->usrs, 0);
+                for (k = 0; k < VPIF_NUMOBJECTS; k++) {
+                        ch->common[k].numbuffers = 0;
+                        common = &ch->common[k];
+                        common->io_usrs = 0;
+                        common->started = 0;
+                        spin_lock_init(&common->irqlock);
+                        mutex_init(&common->lock);
+                        common->numbuffers = 0;
+                        common->set_addr = NULL;
+                        common->ytop_off = 0;
+                        common->ybtm_off = 0;
+                        common->ctop_off = 0;
+                        common->cbtm_off = 0;
+                        common->cur_frm = NULL;
+                        common->next_frm = NULL;
+                        memset(&common->fmt, 0, sizeof(common->fmt));
+                        common->numbuffers = config_params.numbuffers[k];
+                }
+                ch->initialized = 0;
+                if (vpif_obj.config->subdev_count)
+                        ch->sd = vpif_obj.sd[0];
+                ch->channel_id = j;
+                if (j < 2)
+                        ch->common[VPIF_VIDEO_INDEX].numbuffers =
+                            config_params.numbuffers[ch->channel_id];
+                else
+                        ch->common[VPIF_VIDEO_INDEX].numbuffers = 0;
+
+                memset(&ch->vpifparams, 0, sizeof(ch->vpifparams));
+
+                /* Initialize prio member of channel object */
+                v4l2_prio_init(&ch->prio);
+                ch->common[VPIF_VIDEO_INDEX].fmt.type =
+                                                V4L2_BUF_TYPE_VIDEO_OUTPUT;
+                ch->video_dev->lock = &common->lock;
+                video_set_drvdata(ch->video_dev, ch);
+
+                /* select output 0 */
+                err = vpif_set_output(vpif_obj.config, ch, 0);
+                if (err)
+                        goto probe_out;
+
+                /* register video device */
+                vpif_dbg(1, debug, "channel=%x,channel->video_dev=%x\n",
+                         (int)ch, (int)&ch->video_dev);
+
+                err = video_register_device(ch->video_dev,
+                                          VFL_TYPE_GRABBER, (j ? 3 : 2));
+                if (err < 0)
+                        goto probe_out;
+        }
+
+        return 0;
+
+probe_out:
+        for (k = 0; k < j; k++) {
+                ch = vpif_obj.dev[k];
+                video_unregister_device(ch->video_dev);
+                video_device_release(ch->video_dev);
+                ch->video_dev = NULL;
+        }
+        return err;
+}
+
+static int vpif_async_complete(struct v4l2_async_notifier *notifier)
+{
+        return vpif_probe_complete();
+}
+
 /*
  * vpif_probe: This function creates device entries by register itself to the
  * V4L2 driver and initializes fields of each channel objects
@@ -1625,11 +1721,9 @@ vpif_init_free_channel_objects:
 static __init int vpif_probe(struct platform_device *pdev)
 {
         struct vpif_subdev_info *subdevdata;
-        struct vpif_display_config *config;
-        int i, j = 0, k, err = 0;
+        int i, j = 0, err = 0;
         int res_idx = 0;
         struct i2c_adapter *i2c_adap;
-        struct common_obj *common;
         struct channel_obj *ch;
         struct video_device *vfd;
         struct resource *res;
@@ -1708,11 +1802,9 @@ static __init int vpif_probe(struct platform_device *pdev)
                                                                         size/2;
                 }
         }
-
-        i2c_adap = i2c_get_adapter(1);
-        config = pdev->dev.platform_data;
-        subdev_count = config->subdev_count;
-        subdevdata = config->subdevinfo;
+        vpif_obj.config = pdev->dev.platform_data;
+        subdev_count = vpif_obj.config->subdev_count;
+        subdevdata = vpif_obj.config->subdevinfo;
         vpif_obj.sd = kzalloc(sizeof(struct v4l2_subdev *) * subdev_count,
                                                                 GFP_KERNEL);
         if (vpif_obj.sd == NULL) {
@@ -1721,86 +1813,40 @@ static __init int vpif_probe(struct platform_device *pdev)
                 goto vpif_sd_error;
         }
 
-        for (i = 0; i < subdev_count; i++) {
-                vpif_obj.sd[i] = v4l2_i2c_new_subdev_board(&vpif_obj.v4l2_dev,
-                                                i2c_adap,
-                                                &subdevdata[i].board_info,
-                                                NULL);
-                if (!vpif_obj.sd[i]) {
-                        vpif_err("Error registering v4l2 subdevice\n");
-                        err = -ENODEV;
-                        goto probe_subdev_out;
-                }
-
-                if (vpif_obj.sd[i])
-                        vpif_obj.sd[i]->grp_id = 1 << i;
-        }
-
-        for (j = 0; j < VPIF_DISPLAY_MAX_DEVICES; j++) {
-                ch = vpif_obj.dev[j];
-                /* Initialize field of the channel objects */
-                atomic_set(&ch->usrs, 0);
-                for (k = 0; k < VPIF_NUMOBJECTS; k++) {
-                        ch->common[k].numbuffers = 0;
-                        common = &ch->common[k];
-                        common->io_usrs = 0;
-                        common->started = 0;
-                        spin_lock_init(&common->irqlock);
-                        mutex_init(&common->lock);
-                        common->numbuffers = 0;
-                        common->set_addr = NULL;
-                        common->ytop_off = common->ybtm_off = 0;
-                        common->ctop_off = common->cbtm_off = 0;
-                        common->cur_frm = common->next_frm = NULL;
-                        memset(&common->fmt, 0, sizeof(common->fmt));
-                        common->numbuffers = config_params.numbuffers[k];
+        if (!vpif_obj.config->asd_sizes) {
+                i2c_adap = i2c_get_adapter(1);
+                for (i = 0; i < subdev_count; i++) {
+                        vpif_obj.sd[i] =
+                                v4l2_i2c_new_subdev_board(&vpif_obj.v4l2_dev,
+                                                          i2c_adap,
+                                                          &subdevdata[i].
+                                                          board_info,
+                                                          NULL);
+                        if (!vpif_obj.sd[i]) {
+                                vpif_err("Error registering v4l2 subdevice\n");
+                                goto probe_subdev_out;
+                        }
 
+                        if (vpif_obj.sd[i])
+                                vpif_obj.sd[i]->grp_id = 1 << i;
+                }
+                vpif_probe_complete();
+        } else {
+                vpif_obj.notifier.subdev = vpif_obj.config->asd;
+                vpif_obj.notifier.num_subdevs = vpif_obj.config->asd_sizes[0];
+                vpif_obj.notifier.bound = vpif_async_bound;
+                vpif_obj.notifier.complete = vpif_async_complete;
+                err = v4l2_async_notifier_register(&vpif_obj.v4l2_dev,
+                                                   &vpif_obj.notifier);
+                if (err) {
+                        vpif_err("Error registering async notifier\n");
+                        err = -EINVAL;
+                        goto probe_subdev_out;
                 }
-                ch->initialized = 0;
-                if (subdev_count)
-                        ch->sd = vpif_obj.sd[0];
-                ch->channel_id = j;
-                if (j < 2)
-                        ch->common[VPIF_VIDEO_INDEX].numbuffers =
-                            config_params.numbuffers[ch->channel_id];
-                else
-                        ch->common[VPIF_VIDEO_INDEX].numbuffers = 0;
-
-                memset(&ch->vpifparams, 0, sizeof(ch->vpifparams));
-
-                /* Initialize prio member of channel object */
-                v4l2_prio_init(&ch->prio);
-                ch->common[VPIF_VIDEO_INDEX].fmt.type =
-                                                V4L2_BUF_TYPE_VIDEO_OUTPUT;
-                ch->video_dev->lock = &common->lock;
-                video_set_drvdata(ch->video_dev, ch);
-
-                /* select output 0 */
-                err = vpif_set_output(config, ch, 0);
-                if (err)
-                        goto probe_out;
-
-                /* register video device */
-                vpif_dbg(1, debug, "channel=%x,channel->video_dev=%x\n",
-                                (int)ch, (int)&ch->video_dev);
-
-                err = video_register_device(ch->video_dev,
-                                          VFL_TYPE_GRABBER, (j ? 3 : 2));
-                if (err < 0)
-                        goto probe_out;
         }
 
-        v4l2_info(&vpif_obj.v4l2_dev,
-                        " VPIF display driver initialized\n");
         return 0;
 
-probe_out:
-        for (k = 0; k < j; k++) {
-                ch = vpif_obj.dev[k];
-                video_unregister_device(ch->video_dev);
-                video_device_release(ch->video_dev);
-                ch->video_dev = NULL;
-        }
 probe_subdev_out:
         kfree(vpif_obj.sd);
 vpif_sd_error:
diff --git a/drivers/media/platform/davinci/vpif_display.h b/drivers/media/platform/davinci/vpif_display.h
index 5d87fc86e580..4d0485b99a80 100644
--- a/drivers/media/platform/davinci/vpif_display.h
+++ b/drivers/media/platform/davinci/vpif_display.h
@@ -148,7 +148,8 @@ struct vpif_device {
         struct v4l2_device v4l2_dev;
         struct channel_obj *dev[VPIF_DISPLAY_NUM_CHANNELS];
         struct v4l2_subdev **sd;
-
+        struct v4l2_async_notifier notifier;
+        struct vpif_display_config *config;
 };
 
 struct vpif_config_params {
diff --git a/include/media/davinci/vpif_types.h b/include/media/davinci/vpif_types.h
index e08bcde52d05..3cb1704a0650 100644
--- a/include/media/davinci/vpif_types.h
+++ b/include/media/davinci/vpif_types.h
@@ -59,6 +59,8 @@ struct vpif_display_config {
         int subdev_count;
         struct vpif_display_chan_config chan_config[VPIF_DISPLAY_MAX_CHANNELS];
         const char *card_name;
+        struct v4l2_async_subdev **asd; /* Flat array, arranged in groups */
+        int *asd_sizes;         /* 0-terminated array of asd group sizes */
 };
 
 struct vpif_input {