media: v4l2-subdev: add subdev-wide state struct

We have 'struct v4l2_subdev_pad_config' which contains configuration for
a single pad used for the TRY functionality, and an array of those
structs is passed to various v4l2_subdev_pad_ops.

I was working on subdev internal routing between pads, and realized that
there's no way to add TRY functionality for routes, which is not pad
specific configuration. Adding a separate struct for try-route config
wouldn't work either, as e.g. set-fmt needs to know the try-route
configuration to propagate the settings.

This patch adds a new struct, 'struct v4l2_subdev_state' (which at the
moment only contains the v4l2_subdev_pad_config array) and the new
struct is used in most of the places where v4l2_subdev_pad_config was
used. All v4l2_subdev_pad_ops functions taking v4l2_subdev_pad_config
are changed to instead take v4l2_subdev_state.

The changes to drivers/media/v4l2-core/v4l2-subdev.c and
include/media/v4l2-subdev.h were written by hand, and all the driver
changes were done with the semantic patch below. The spatch needs to be
applied to a select list of directories. I used the following shell
commands to apply the spatch:

dirs="drivers/media/i2c drivers/media/platform drivers/media/usb drivers/media/test-drivers/vimc drivers/media/pci drivers/staging/media"
for dir in $dirs; do spatch -j8 --dir --include-headers --no-show-diff --in-place --sp-file v4l2-subdev-state.cocci $dir; done

Note that Coccinelle chokes on a few drivers (gcc extensions?). With
minor changes we can make Coccinelle run fine, and these changes can be
reverted after spatch. The diff for these changes is:

For drivers/media/i2c/s5k5baf.c:

	@@ -1481,7 +1481,7 @@ static int s5k5baf_set_selection(struct v4l2_subdev *sd,
	 				&s5k5baf_cis_rect,
	 				v4l2_subdev_get_try_crop(sd, cfg, PAD_CIS),
	 				v4l2_subdev_get_try_compose(sd, cfg, PAD_CIS),
	-				v4l2_subdev_get_try_crop(sd, cfg, PAD_OUT)
	+				v4l2_subdev_get_try_crop(sd, cfg, PAD_OUT),
	 			};
	 		s5k5baf_set_rect_and_adjust(rects, rtype, &sel->r);
	 		return 0;

For drivers/media/platform/s3c-camif/camif-capture.c:

	@@ -1230,7 +1230,7 @@ static int s3c_camif_subdev_get_fmt(struct v4l2_subdev *sd,
	 		*mf = camif->mbus_fmt;
	 		break;

	-	case CAMIF_SD_PAD_SOURCE_C...CAMIF_SD_PAD_SOURCE_P:
	+	case CAMIF_SD_PAD_SOURCE_C:
	 		/* crop rectangle at camera interface input */
	 		mf->width = camif->camif_crop.width;
	 		mf->height = camif->camif_crop.height;
	@@ -1332,7 +1332,7 @@ static int s3c_camif_subdev_set_fmt(struct v4l2_subdev *sd,
	 		}
	 		break;

	-	case CAMIF_SD_PAD_SOURCE_C...CAMIF_SD_PAD_SOURCE_P:
	+	case CAMIF_SD_PAD_SOURCE_C:
	 		/* Pixel format can be only changed on the sink pad. */
	 		mf->code = camif->mbus_fmt.code;
	 		mf->width = crop->width;

The semantic patch is:

// <smpl>

// Change function parameter

@@
identifier func;
identifier cfg;
@@

 func(...,
-   struct v4l2_subdev_pad_config *cfg
+   struct v4l2_subdev_state *sd_state
    , ...)
 {
 <...
- cfg
+ sd_state
 ...>
 }

// Change function declaration parameter

@@
identifier func;
identifier cfg;
type T;
@@
T func(...,
-   struct v4l2_subdev_pad_config *cfg
+   struct v4l2_subdev_state *sd_state
    , ...);

// Change function return value

@@
identifier func;
@@
- struct v4l2_subdev_pad_config
+ struct v4l2_subdev_state
 *func(...)
 {
    ...
 }

// Change function declaration return value

@@
identifier func;
@@
- struct v4l2_subdev_pad_config
+ struct v4l2_subdev_state
 *func(...);

// Some drivers pass a local pad_cfg for a single pad to a called function. Wrap it
// inside a pad_state.

@@
identifier func;
identifier pad_cfg;
@@
func(...)
{
    ...
    struct v4l2_subdev_pad_config pad_cfg;
+   struct v4l2_subdev_state pad_state = { .pads = &pad_cfg };

    <+...

(
    v4l2_subdev_call
|
    sensor_call
|
    isi_try_fse
|
    isc_try_fse
|
    saa_call_all
)
    (...,
-   &pad_cfg
+   &pad_state
    ,...)

    ...+>
}

// If the function uses fields from pad_config, access via state->pads

@@
identifier func;
identifier state;
@@
 func(...,
    struct v4l2_subdev_state *state
    , ...)
 {
    <...
(
-   state->try_fmt
+   state->pads->try_fmt
|
-   state->try_crop
+   state->pads->try_crop
|
-   state->try_compose
+   state->pads->try_compose
)
    ...>
}

// If the function accesses the filehandle, use fh->state instead

@@
struct v4l2_subdev_fh *fh;
@@
-    fh->pad
+    fh->state

@@
struct v4l2_subdev_fh fh;
@@
-    fh.pad
+    fh.state

// Start of vsp1 specific

@@
@@
struct vsp1_entity {
    ...
-    struct v4l2_subdev_pad_config *config;
+    struct v4l2_subdev_state *config;
    ...
};

@@
symbol entity;
@@
vsp1_entity_init(...)
{
    ...
    entity->config =
-    v4l2_subdev_alloc_pad_config
+    v4l2_subdev_alloc_state
    (&entity->subdev);
    ...
}

@@
symbol entity;
@@
vsp1_entity_destroy(...)
{
    ...
-   v4l2_subdev_free_pad_config
+   v4l2_subdev_free_state
    (entity->config);
    ...
}

@exists@
identifier func =~ "(^vsp1.*)|(hsit_set_format)|(sru_enum_frame_size)|(sru_set_format)|(uif_get_selection)|(uif_set_selection)|(uds_enum_frame_size)|(uds_set_format)|(brx_set_format)|(brx_get_selection)|(histo_get_selection)|(histo_set_selection)|(brx_set_selection)";
symbol config;
@@
func(...) {
    ...
-    struct v4l2_subdev_pad_config *config;
+    struct v4l2_subdev_state *config;
    ...
}

// End of vsp1 specific

// Start of rcar specific

@@
identifier sd;
identifier pad_cfg;
@@
 rvin_try_format(...)
 {
    ...
-   struct v4l2_subdev_pad_config *pad_cfg;
+   struct v4l2_subdev_state *sd_state;
    ...
-   pad_cfg = v4l2_subdev_alloc_pad_config(sd);
+   sd_state = v4l2_subdev_alloc_state(sd);
    <...
-   pad_cfg
+   sd_state
    ...>
-   v4l2_subdev_free_pad_config(pad_cfg);
+   v4l2_subdev_free_state(sd_state);
    ...
 }

// End of rcar specific

// Start of rockchip specific

@@
identifier func =~ "(rkisp1_rsz_get_pad_fmt)|(rkisp1_rsz_get_pad_crop)|(rkisp1_rsz_register)";
symbol rsz;
symbol pad_cfg;
@@

 func(...)
 {
+   struct v4l2_subdev_state state = { .pads = rsz->pad_cfg };
    ...
-   rsz->pad_cfg
+   &state
    ...
 }

@@
identifier func =~ "(rkisp1_isp_get_pad_fmt)|(rkisp1_isp_get_pad_crop)";
symbol isp;
symbol pad_cfg;
@@

 func(...)
 {
+   struct v4l2_subdev_state state = { .pads = isp->pad_cfg };
    ...
-   isp->pad_cfg
+   &state
    ...
 }

@@
symbol rkisp1;
symbol isp;
symbol pad_cfg;
@@

 rkisp1_isp_register(...)
 {
+   struct v4l2_subdev_state state = { .pads = rkisp1->isp.pad_cfg };
    ...
-   rkisp1->isp.pad_cfg
+   &state
    ...
 }

// End of rockchip specific

// Start of tegra-video specific

@@
identifier sd;
identifier pad_cfg;
@@
 __tegra_channel_try_format(...)
 {
    ...
-   struct v4l2_subdev_pad_config *pad_cfg;
+   struct v4l2_subdev_state *sd_state;
    ...
-   pad_cfg = v4l2_subdev_alloc_pad_config(sd);
+   sd_state = v4l2_subdev_alloc_state(sd);
    <...
-   pad_cfg
+   sd_state
    ...>
-   v4l2_subdev_free_pad_config(pad_cfg);
+   v4l2_subdev_free_state(sd_state);
    ...
 }

@@
identifier sd_state;
@@
 __tegra_channel_try_format(...)
 {
    ...
    struct v4l2_subdev_state *sd_state;
    <...
-   sd_state->try_crop
+   sd_state->pads->try_crop
    ...>
 }

// End of tegra-video specific

// </smpl>

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

1 files changed, 80 insertions, 62 deletions

diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
index 956dafab43d4..6d3e03036519 100644
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -26,19 +26,21 @@
 #if defined(CONFIG_VIDEO_V4L2_SUBDEV_API)
 static int subdev_fh_init(struct v4l2_subdev_fh *fh, struct v4l2_subdev *sd)
 {
-	if (sd->entity.num_pads) {
-		fh->pad = v4l2_subdev_alloc_pad_config(sd);
-		if (fh->pad == NULL)
-			return -ENOMEM;
-	}
+	struct v4l2_subdev_state *state;
+
+	state = v4l2_subdev_alloc_state(sd);
+	if (IS_ERR(state))
+		return PTR_ERR(state);
+
+	fh->state = state;
 
 	return 0;
 }
 
 static void subdev_fh_free(struct v4l2_subdev_fh *fh)
 {
-	v4l2_subdev_free_pad_config(fh->pad);
-	fh->pad = NULL;
+	v4l2_subdev_free_state(fh->state);
+	fh->state = NULL;
 }
 
 static int subdev_open(struct file *file)
@@ -146,63 +148,63 @@ static inline int check_pad(struct v4l2_subdev *sd, u32 pad)
 	return 0;
 }
 
-static int check_cfg(u32 which, struct v4l2_subdev_pad_config *cfg)
+static int check_state_pads(u32 which, struct v4l2_subdev_state *state)
 {
-	if (which == V4L2_SUBDEV_FORMAT_TRY && !cfg)
+	if (which == V4L2_SUBDEV_FORMAT_TRY && (!state || !state->pads))
 		return -EINVAL;
 
 	return 0;
 }
 
 static inline int check_format(struct v4l2_subdev *sd,
-			       struct v4l2_subdev_pad_config *cfg,
+			       struct v4l2_subdev_state *state,
 			       struct v4l2_subdev_format *format)
 {
 	if (!format)
 		return -EINVAL;
 
 	return check_which(format->which) ? : check_pad(sd, format->pad) ? :
-	       check_cfg(format->which, cfg);
+	       check_state_pads(format->which, state);
 }
 
 static int call_get_fmt(struct v4l2_subdev *sd,
-			struct v4l2_subdev_pad_config *cfg,
+			struct v4l2_subdev_state *state,
 			struct v4l2_subdev_format *format)
 {
-	return check_format(sd, cfg, format) ? :
-	       sd->ops->pad->get_fmt(sd, cfg, format);
+	return check_format(sd, state, format) ? :
+	       sd->ops->pad->get_fmt(sd, state, format);
 }
 
 static int call_set_fmt(struct v4l2_subdev *sd,
-			struct v4l2_subdev_pad_config *cfg,
+			struct v4l2_subdev_state *state,
 			struct v4l2_subdev_format *format)
 {
-	return check_format(sd, cfg, format) ? :
-	       sd->ops->pad->set_fmt(sd, cfg, format);
+	return check_format(sd, state, format) ? :
+	       sd->ops->pad->set_fmt(sd, state, format);
 }
 
 static int call_enum_mbus_code(struct v4l2_subdev *sd,
-			       struct v4l2_subdev_pad_config *cfg,
+			       struct v4l2_subdev_state *state,
 			       struct v4l2_subdev_mbus_code_enum *code)
 {
 	if (!code)
 		return -EINVAL;
 
 	return check_which(code->which) ? : check_pad(sd, code->pad) ? :
-	       check_cfg(code->which, cfg) ? :
-	       sd->ops->pad->enum_mbus_code(sd, cfg, code);
+	       check_state_pads(code->which, state) ? :
+	       sd->ops->pad->enum_mbus_code(sd, state, code);
 }
 
 static int call_enum_frame_size(struct v4l2_subdev *sd,
-				struct v4l2_subdev_pad_config *cfg,
+				struct v4l2_subdev_state *state,
 				struct v4l2_subdev_frame_size_enum *fse)
 {
 	if (!fse)
 		return -EINVAL;
 
 	return check_which(fse->which) ? : check_pad(sd, fse->pad) ? :
-	       check_cfg(fse->which, cfg) ? :
-	       sd->ops->pad->enum_frame_size(sd, cfg, fse);
+	       check_state_pads(fse->which, state) ? :
+	       sd->ops->pad->enum_frame_size(sd, state, fse);
 }
 
 static inline int check_frame_interval(struct v4l2_subdev *sd,
@@ -229,42 +231,42 @@ static int call_s_frame_interval(struct v4l2_subdev *sd,
 }
 
 static int call_enum_frame_interval(struct v4l2_subdev *sd,
-				    struct v4l2_subdev_pad_config *cfg,
+				    struct v4l2_subdev_state *state,
 				    struct v4l2_subdev_frame_interval_enum *fie)
 {
 	if (!fie)
 		return -EINVAL;
 
 	return check_which(fie->which) ? : check_pad(sd, fie->pad) ? :
-	       check_cfg(fie->which, cfg) ? :
-	       sd->ops->pad->enum_frame_interval(sd, cfg, fie);
+	       check_state_pads(fie->which, state) ? :
+	       sd->ops->pad->enum_frame_interval(sd, state, fie);
 }
 
 static inline int check_selection(struct v4l2_subdev *sd,
-				  struct v4l2_subdev_pad_config *cfg,
+				  struct v4l2_subdev_state *state,
 				  struct v4l2_subdev_selection *sel)
 {
 	if (!sel)
 		return -EINVAL;
 
 	return check_which(sel->which) ? : check_pad(sd, sel->pad) ? :
-	       check_cfg(sel->which, cfg);
+	       check_state_pads(sel->which, state);
 }
 
 static int call_get_selection(struct v4l2_subdev *sd,
-			      struct v4l2_subdev_pad_config *cfg,
+			      struct v4l2_subdev_state *state,
 			      struct v4l2_subdev_selection *sel)
 {
-	return check_selection(sd, cfg, sel) ? :
-	       sd->ops->pad->get_selection(sd, cfg, sel);
+	return check_selection(sd, state, sel) ? :
+	       sd->ops->pad->get_selection(sd, state, sel);
 }
 
 static int call_set_selection(struct v4l2_subdev *sd,
-			      struct v4l2_subdev_pad_config *cfg,
+			      struct v4l2_subdev_state *state,
 			      struct v4l2_subdev_selection *sel)
 {
-	return check_selection(sd, cfg, sel) ? :
-	       sd->ops->pad->set_selection(sd, cfg, sel);
+	return check_selection(sd, state, sel) ? :
+	       sd->ops->pad->set_selection(sd, state, sel);
 }
 
 static inline int check_edid(struct v4l2_subdev *sd,
@@ -506,7 +508,7 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 
 		memset(format->reserved, 0, sizeof(format->reserved));
 		memset(format->format.reserved, 0, sizeof(format->format.reserved));
-		return v4l2_subdev_call(sd, pad, get_fmt, subdev_fh->pad, format);
+		return v4l2_subdev_call(sd, pad, get_fmt, subdev_fh->state, format);
 	}
 
 	case VIDIOC_SUBDEV_S_FMT: {
@@ -517,7 +519,7 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 
 		memset(format->reserved, 0, sizeof(format->reserved));
 		memset(format->format.reserved, 0, sizeof(format->format.reserved));
-		return v4l2_subdev_call(sd, pad, set_fmt, subdev_fh->pad, format);
+		return v4l2_subdev_call(sd, pad, set_fmt, subdev_fh->state, format);
 	}
 
 	case VIDIOC_SUBDEV_G_CROP: {
@@ -531,7 +533,7 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 		sel.target = V4L2_SEL_TGT_CROP;
 
 		rval = v4l2_subdev_call(
-			sd, pad, get_selection, subdev_fh->pad, &sel);
+			sd, pad, get_selection, subdev_fh->state, &sel);
 
 		crop->rect = sel.r;
 
@@ -553,7 +555,7 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 		sel.r = crop->rect;
 
 		rval = v4l2_subdev_call(
-			sd, pad, set_selection, subdev_fh->pad, &sel);
+			sd, pad, set_selection, subdev_fh->state, &sel);
 
 		crop->rect = sel.r;
 
@@ -564,7 +566,7 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 		struct v4l2_subdev_mbus_code_enum *code = arg;
 
 		memset(code->reserved, 0, sizeof(code->reserved));
-		return v4l2_subdev_call(sd, pad, enum_mbus_code, subdev_fh->pad,
+		return v4l2_subdev_call(sd, pad, enum_mbus_code, subdev_fh->state,
 					code);
 	}
 
@@ -572,7 +574,7 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 		struct v4l2_subdev_frame_size_enum *fse = arg;
 
 		memset(fse->reserved, 0, sizeof(fse->reserved));
-		return v4l2_subdev_call(sd, pad, enum_frame_size, subdev_fh->pad,
+		return v4l2_subdev_call(sd, pad, enum_frame_size, subdev_fh->state,
 					fse);
 	}
 
@@ -597,7 +599,7 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 		struct v4l2_subdev_frame_interval_enum *fie = arg;
 
 		memset(fie->reserved, 0, sizeof(fie->reserved));
-		return v4l2_subdev_call(sd, pad, enum_frame_interval, subdev_fh->pad,
+		return v4l2_subdev_call(sd, pad, enum_frame_interval, subdev_fh->state,
 					fie);
 	}
 
@@ -606,7 +608,7 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 
 		memset(sel->reserved, 0, sizeof(sel->reserved));
 		return v4l2_subdev_call(
-			sd, pad, get_selection, subdev_fh->pad, sel);
+			sd, pad, get_selection, subdev_fh->state, sel);
 	}
 
 	case VIDIOC_SUBDEV_S_SELECTION: {
@@ -617,7 +619,7 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 
 		memset(sel->reserved, 0, sizeof(sel->reserved));
 		return v4l2_subdev_call(
-			sd, pad, set_selection, subdev_fh->pad, sel);
+			sd, pad, set_selection, subdev_fh->state, sel);
 	}
 
 	case VIDIOC_G_EDID: {
@@ -892,35 +894,51 @@ int v4l2_subdev_link_validate(struct media_link *link)
 }
 EXPORT_SYMBOL_GPL(v4l2_subdev_link_validate);
 
-struct v4l2_subdev_pad_config *
-v4l2_subdev_alloc_pad_config(struct v4l2_subdev *sd)
+struct v4l2_subdev_state *v4l2_subdev_alloc_state(struct v4l2_subdev *sd)
 {
-	struct v4l2_subdev_pad_config *cfg;
+	struct v4l2_subdev_state *state;
 	int ret;
 
-	if (!sd->entity.num_pads)
-		return NULL;
+	state = kzalloc(sizeof(*state), GFP_KERNEL);
+	if (!state)
+		return ERR_PTR(-ENOMEM);
 
-	cfg = kvmalloc_array(sd->entity.num_pads, sizeof(*cfg),
-			     GFP_KERNEL | __GFP_ZERO);
-	if (!cfg)
-		return NULL;
-
-	ret = v4l2_subdev_call(sd, pad, init_cfg, cfg);
-	if (ret < 0 && ret != -ENOIOCTLCMD) {
-		kvfree(cfg);
-		return NULL;
+	if (sd->entity.num_pads) {
+		state->pads = kvmalloc_array(sd->entity.num_pads,
+					     sizeof(*state->pads),
+					     GFP_KERNEL | __GFP_ZERO);
+		if (!state->pads) {
+			ret = -ENOMEM;
+			goto err;
+		}
 	}
 
-	return cfg;
+	ret = v4l2_subdev_call(sd, pad, init_cfg, state);
+	if (ret < 0 && ret != -ENOIOCTLCMD)
+		goto err;
+
+	return state;
+
+err:
+	if (state && state->pads)
+		kvfree(state->pads);
+
+	kfree(state);
+
+	return ERR_PTR(ret);
 }
-EXPORT_SYMBOL_GPL(v4l2_subdev_alloc_pad_config);
+EXPORT_SYMBOL_GPL(v4l2_subdev_alloc_state);
 
-void v4l2_subdev_free_pad_config(struct v4l2_subdev_pad_config *cfg)
+void v4l2_subdev_free_state(struct v4l2_subdev_state *state)
 {
-	kvfree(cfg);
+	if (!state)
+		return;
+
+	kvfree(state->pads);
+	kfree(state);
 }
-EXPORT_SYMBOL_GPL(v4l2_subdev_free_pad_config);
+EXPORT_SYMBOL_GPL(v4l2_subdev_free_state);
+
 #endif /* CONFIG_MEDIA_CONTROLLER */
 
 void v4l2_subdev_init(struct v4l2_subdev *sd, const struct v4l2_subdev_ops *ops)