[RESEND PATCH v4 00/21] Add Tegra20 parallel video input capture

[RESEND PATCH v4 00/21] Add Tegra20 parallel video input capture

[Luca Ceresoli]

TL;DR: Resending this series with Rob's review tag added. Now all DT
patches have at least a reviewed-by tag from Rob or Krzysztof, all the
driver patches have one from Dmitry.

Full details follow.

Tegra20 and other Tegra SoCs have a video input (VI) peripheral that can
receive from either MIPI CSI-2 or parallel video (called respectively "CSI"
and "VIP" in the documentation). The kernel currently has a staging driver
for Tegra210 CSI capture. This patch set adds support for Tegra20 VIP
capture.

Unfortunately I had no real documentation available to base this work on.
I only had a working downstream 3.1 kernel, so I started with the driver
found there and heavily reworked it to fit into the mainline tegra-video
driver structure. The existing code appears written with the intent of
being modular and allow adding new input mechanisms and new SoCs while
keeping a unique VI core module. However its modularity and extensibility
was not enough to add Tegra20 VIP support, so I added some hooks to turn
hard-coded behaviour into per-SoC or per-bus customizable code. There are
also a fix, some generic cleanups and DT bindings.

Quick tour of the patches:

 * Device tree bindings

   01. dt-bindings: display: tegra: add Tegra20 VIP
   02. dt-bindings: display: tegra: vi: add 'vip' property and example

 * A fix

   03. staging: media: tegra-video: fix .vidioc_enum_fmt_vid_cap to return all formats

 * Minor improvements to logging, comments, cleanups

   04. staging: media: tegra-video: improve documentation of tegra_video_format fields
   05. staging: media: tegra-video: document tegra_channel_get_remote_source_subdev
   06. staging: media: tegra-video: fix typos in comment
   07. staging: media: tegra-video: improve error messages
   08. staging: media: tegra-video: slightly simplify cleanup on errors
   09. staging: media: tegra-video: move private struct declaration to C file
   10. staging: media: tegra-video: move tegra210_csi_soc to C file
   11. staging: media: tegra-video: remove unneeded include

 * Preparation to make the VI module generic enough to host Tegra20 and VIP

   12. staging: media: tegra-video: Kconfig: allow TPG only on Tegra210
   13. staging: media: tegra-video: move tegra_channel_fmt_align to a per-soc op
   14. staging: media: tegra-video: move default format to soc-specific data
   15. staging: media: tegra-video: move MIPI calibration calls from VI to CSI
   16. staging: media: tegra-video: add a per-soc enable/disable op
   17. staging: media: tegra-video: move syncpt init/free to a per-soc op
   18. staging: media: tegra-video: add syncpts for Tegra20 to struct tegra_vi
   19. staging: media: tegra-video: add hooks for planar YUV and H/V flip
   20. staging: media: tegra-video: add H/V flip controls

 * Implementation of VIP and Tegra20

   21. staging: media: tegra-video: add support for Tegra20 parallel input

Enjoy!

Changed in RESEND,v4:
- add Rob's review tag on patch 2

Changed in v4:
- fixed the leftovers after the removal of 'channel@0' in DT
- added review tags by Dimtry

Changed in v3:
- removed the 'channel@0' node from the device tree representation of vip
- squashed the last two patches (VIP + T20) into one
- small cleanups
- rebase on v6.2-rc1

Changed in v2:
- improved dt-bindings patches based on reviews
- removed patches 3 and 4 adding DT labels without a mainline user
- two small fixes to the last patch

[v4] https://lore.kernel.org/linux-tegra/20230130141603.323221-1-luca.ceresoli@bootlin.com/
[v3] https://lore.kernel.org/linux-media/20221229133205.981397-1-luca.ceresoli@bootlin.com/
[v2] https://lore.kernel.org/linux-tegra/20221222100328.6e341874@booty/T/#t
[v1] https://lore.kernel.org/linux-tegra/20221124155634.5bc2a423@booty/T/#t

Luca

Luca Ceresoli (21):
  dt-bindings: display: tegra: add Tegra20 VIP
  dt-bindings: display: tegra: vi: add 'vip' property and example
  staging: media: tegra-video: fix .vidioc_enum_fmt_vid_cap to return
    all formats
  staging: media: tegra-video: improve documentation of
    tegra_video_format fields
  staging: media: tegra-video: document
    tegra_channel_get_remote_source_subdev
  staging: media: tegra-video: fix typos in comment
  staging: media: tegra-video: improve error messages
  staging: media: tegra-video: slightly simplify cleanup on errors
  staging: media: tegra-video: move private struct declaration to C file
  staging: media: tegra-video: move tegra210_csi_soc to C file
  staging: media: tegra-video: remove unneeded include
  staging: media: tegra-video: Kconfig: allow TPG only on Tegra210
  staging: media: tegra-video: move tegra_channel_fmt_align to a per-soc
    op
  staging: media: tegra-video: move default format to soc-specific data
  staging: media: tegra-video: move MIPI calibration calls from VI to
    CSI
  staging: media: tegra-video: add a per-soc enable/disable op
  staging: media: tegra-video: move syncpt init/free to a per-soc op
  staging: media: tegra-video: add syncpts for Tegra20 to struct
    tegra_vi
  staging: media: tegra-video: add hooks for planar YUV and H/V flip
  staging: media: tegra-video: add H/V flip controls
  staging: media: tegra-video: add support for Tegra20 parallel input

 .../display/tegra/nvidia,tegra20-vi.yaml      |  59 ++
 .../display/tegra/nvidia,tegra20-vip.yaml     |  41 ++
 MAINTAINERS                                   |   3 +
 drivers/staging/media/tegra-video/Kconfig     |   1 +
 drivers/staging/media/tegra-video/Makefile    |   2 +
 drivers/staging/media/tegra-video/csi.c       |  48 ++
 drivers/staging/media/tegra-video/csi.h       |   4 -
 drivers/staging/media/tegra-video/tegra20.c   | 661 ++++++++++++++++++
 drivers/staging/media/tegra-video/tegra210.c  |  97 ++-
 drivers/staging/media/tegra-video/vi.c        | 321 ++-------
 drivers/staging/media/tegra-video/vi.h        |  75 +-
 drivers/staging/media/tegra-video/video.c     |   5 +
 drivers/staging/media/tegra-video/video.h     |   2 +-
 drivers/staging/media/tegra-video/vip.c       | 290 ++++++++
 drivers/staging/media/tegra-video/vip.h       |  68 ++
 15 files changed, 1387 insertions(+), 290 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-vip.yaml
 create mode 100644 drivers/staging/media/tegra-video/tegra20.c
 create mode 100644 drivers/staging/media/tegra-video/vip.c
 create mode 100644 drivers/staging/media/tegra-video/vip.h

-- 
2.34.1

[RESEND PATCH v4 01/21] dt-bindings: display: tegra: add Tegra20 VIP

[Luca Ceresoli]

VIP is the parallel video capture component within the video input
subsystem of Tegra20 (and other Tegra chips, apparently).

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>

---

Changed in v4:
 - Added review tags
 - remove leftover lines after removal of 'channel@0'

Changed in v3:
 - remove channel@0 node (Krzysztof, Rob, Dmitry)
 - add myself as a maintainer of the whole Tegra video driver (Dmitry)

Changed in v2 (suggested by Krzysztof Kozlowski):
 - remove redundant "bindings" from subject line
 - remove $nodename
 - add channel@0 description
 - add reg: const: 0
---
 .../display/tegra/nvidia,tegra20-vip.yaml     | 41 +++++++++++++++++++
 MAINTAINERS                                   |  2 +
 2 files changed, 43 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-vip.yaml

diff --git a/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-vip.yaml b/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-vip.yaml
new file mode 100644
index 000000000000..14294edb8d8c
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-vip.yaml
@@ -0,0 +1,41 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/tegra/nvidia,tegra20-vip.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: NVIDIA Tegra VIP (parallel video capture) controller
+
+maintainers:
+  - Luca Ceresoli <luca.ceresoli@bootlin.com>
+
+properties:
+  compatible:
+    enum:
+      - nvidia,tegra20-vip
+
+  ports:
+    $ref: /schemas/graph.yaml#/properties/ports
+
+    properties:
+      port@0:
+        $ref: /schemas/graph.yaml#/properties/port
+        description:
+          Port receiving the video stream from the sensor
+
+      port@1:
+        $ref: /schemas/graph.yaml#/properties/port
+        description:
+          Port sending the video stream to the VI
+
+    required:
+      - port@0
+      - port@1
+
+unevaluatedProperties: false
+
+required:
+  - compatible
+  - ports
+
+# see nvidia,tegra20-vi.yaml for an example
diff --git a/MAINTAINERS b/MAINTAINERS
index 8d5bc223f305..40c069c23d61 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -20621,10 +20621,12 @@ TEGRA VIDEO DRIVER
 M:	Thierry Reding <thierry.reding@gmail.com>
 M:	Jonathan Hunter <jonathanh@nvidia.com>
 M:	Sowjanya Komatineni <skomatineni@nvidia.com>
+M:	Luca Ceresoli <luca.ceresoli@bootlin.com>
 L:	linux-media@vger.kernel.org
 L:	linux-tegra@vger.kernel.org
 S:	Maintained
 F:	Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-host1x.yaml
+F:	Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-vip.yaml
 F:	drivers/staging/media/tegra-video/
 
 TEGRA XUSB PADCTL DRIVER
-- 
2.34.1

[RESEND PATCH v4 02/21] dt-bindings: display: tegra: vi: add 'vip' property and example

[Luca Ceresoli]

The Tegra20 VI peripheral can receive parallel input from the VIP parallel
input module. Add it to the allowed properties and augment the existing
nvidia,tegra20-vi example to show a 'vip' property.

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>

---

Changed in RESEND,v4:
 - Add Reviewed-by: Rob Herring <robh@kernel.org>

Changed in v4:
 - complete the removal of 'channel@0'

Changed in v3 (suggested by Rob Herring):
 - drop 'endpoint', unneeded as there's no extra properties in the
   endpoints

Changed in v2 (suggested by Krzysztof Kozlowski):
 - rename "i2c3" -> "ic2"
 - add review tag
---
 .../display/tegra/nvidia,tegra20-vi.yaml      | 59 +++++++++++++++++++
 MAINTAINERS                                   |  1 +
 2 files changed, 60 insertions(+)

diff --git a/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-vi.yaml b/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-vi.yaml
index a42bf33d1e7d..2181855a0920 100644
--- a/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-vi.yaml
+++ b/Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-vi.yaml
@@ -73,6 +73,18 @@ properties:
   avdd-dsi-csi-supply:
     description: DSI/CSI power supply. Must supply 1.2 V.
 
+  vip:
+    $ref: /schemas/display/tegra/nvidia,tegra20-vip.yaml
+
+  ports:
+    $ref: /schemas/graph.yaml#/properties/ports
+
+    properties:
+      port@0:
+        $ref: /schemas/graph.yaml#/properties/port
+        description:
+          Input from the VIP (parallel input capture) module
+
 patternProperties:
   "^csi@[0-9a-f]+$":
     type: object
@@ -108,6 +120,22 @@ examples:
     #include <dt-bindings/clock/tegra20-car.h>
     #include <dt-bindings/interrupt-controller/arm-gic.h>
 
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+        camera@48 {
+            compatible = "aptina,mt9v111";
+            reg = <0x48>;
+            clocks = <&camera_clk>;
+
+            port {
+                mt9v111_out: endpoint {
+                    remote-endpoint = <&vi_vip_in>;
+                };
+            };
+        };
+    };
+
     vi@54080000 {
         compatible = "nvidia,tegra20-vi";
         reg = <0x54080000 0x00040000>;
@@ -115,6 +143,37 @@ examples:
         clocks = <&tegra_car TEGRA20_CLK_VI>;
         resets = <&tegra_car 100>;
         reset-names = "vi";
+
+        vip {
+            compatible = "nvidia,tegra20-vip";
+            ports {
+                #address-cells = <1>;
+                #size-cells = <0>;
+                port@0 {
+                    reg = <0>;
+                    vi_vip_in: endpoint {
+                        remote-endpoint = <&mt9v111_out>;
+                    };
+                };
+                port@1 {
+                    reg = <1>;
+                    vi_vip_out: endpoint {
+                        remote-endpoint = <&vi_in>;
+                    };
+                };
+            };
+        };
+
+        ports {
+            #address-cells = <1>;
+            #size-cells = <0>;
+            port@0 {
+                reg = <0>;
+                vi_in: endpoint {
+                    remote-endpoint = <&vi_vip_out>;
+                };
+            };
+        };
     };
 
   - |
diff --git a/MAINTAINERS b/MAINTAINERS
index 40c069c23d61..9442f3458924 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -20626,6 +20626,7 @@ L:	linux-media@vger.kernel.org
 L:	linux-tegra@vger.kernel.org
 S:	Maintained
 F:	Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-host1x.yaml
+F:	Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-vi.yaml
 F:	Documentation/devicetree/bindings/display/tegra/nvidia,tegra20-vip.yaml
 F:	drivers/staging/media/tegra-video/
 
-- 
2.34.1

[RESEND PATCH v4 03/21] staging: media: tegra-video: fix .vidioc_enum_fmt_vid_cap to return all formats

[Luca Ceresoli]

The .vidioc_enum_fmt_vid_cap (called tegra_channel_enum_format() here)
should return all the supported formats. Instead the current implementation
computes the intersection between the formats it supports and those
supported by the first subdev in the stream (typically the image sensor).

Remove all the unnecessary logic that supports such algorithm. In order to
do this, also change the Tegra210 CSI TPG formats from the current
open-coded implementation in vi_tpg_fmts_bitmap_init() to a const array in
tegra210.c, just like the one that describes the regular formats.

Fixes: 3d8a97eabef0 ("media: tegra-video: Add Tegra210 Video input driver")
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>

---

Changed in v4:
 - Added review tags

No changes in v3
No changes in v2
---
 drivers/staging/media/tegra-video/tegra210.c |   7 +-
 drivers/staging/media/tegra-video/vi.c       | 103 +------------------
 drivers/staging/media/tegra-video/vi.h       |   4 -
 3 files changed, 9 insertions(+), 105 deletions(-)

diff --git a/drivers/staging/media/tegra-video/tegra210.c b/drivers/staging/media/tegra-video/tegra210.c
index d58370a84737..eb19dd5107ce 100644
--- a/drivers/staging/media/tegra-video/tegra210.c
+++ b/drivers/staging/media/tegra-video/tegra210.c
@@ -683,8 +683,12 @@ enum tegra210_image_format {
 	V4L2_PIX_FMT_##FOURCC,						\
 }
 
-/* Tegra210 supported video formats */
 static const struct tegra_video_format tegra210_video_formats[] = {
+#if IS_ENABLED(CONFIG_VIDEO_TEGRA_TPG)
+	/* VI only support 2 formats in TPG mode */
+	TEGRA210_VIDEO_FMT(RAW10,  10, SRGGB10_1X10,      2, T_R16_I,    SRGGB10),
+	TEGRA210_VIDEO_FMT(RGB888, 24, RGB888_1X32_PADHI, 4, T_A8B8G8R8, RGBX32),
+#else
 	/* RAW 8 */
 	TEGRA210_VIDEO_FMT(RAW8, 8, SRGGB8_1X8, 1, T_L8, SRGGB8),
 	TEGRA210_VIDEO_FMT(RAW8, 8, SGRBG8_1X8, 1, T_L8, SGRBG8),
@@ -714,6 +718,7 @@ static const struct tegra_video_format tegra210_video_formats[] = {
 	TEGRA210_VIDEO_FMT(YUV422_8, 16, VYUY8_2X8, 2, T_V8_Y8__U8_Y8, YUYV),
 	TEGRA210_VIDEO_FMT(YUV422_8, 16, YUYV8_2X8, 2, T_Y8_U8__Y8_V8, VYUY),
 	TEGRA210_VIDEO_FMT(YUV422_8, 16, YVYU8_2X8, 2, T_Y8_V8__Y8_U8, UYVY),
+#endif
 };
 
 /* Tegra210 VI operations */
diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index 11dd142c98c5..9dba6e97ebdd 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -3,7 +3,6 @@
  * Copyright (C) 2020 NVIDIA CORPORATION.  All rights reserved.
  */
 
-#include <linux/bitmap.h>
 #include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/host1x.h>
@@ -73,15 +72,6 @@ static int tegra_get_format_idx_by_code(struct tegra_vi *vi,
 	return -1;
 }
 
-static u32 tegra_get_format_fourcc_by_idx(struct tegra_vi *vi,
-					  unsigned int index)
-{
-	if (index >= vi->soc->nformats)
-		return -EINVAL;
-
-	return vi->soc->video_formats[index].fourcc;
-}
-
 static const struct tegra_video_format *
 tegra_get_format_by_fourcc(struct tegra_vi *vi, u32 fourcc)
 {
@@ -430,19 +420,12 @@ static int tegra_channel_enum_format(struct file *file, void *fh,
 				     struct v4l2_fmtdesc *f)
 {
 	struct tegra_vi_channel *chan = video_drvdata(file);
-	unsigned int index = 0, i;
-	unsigned long *fmts_bitmap = chan->tpg_fmts_bitmap;
-
-	if (!IS_ENABLED(CONFIG_VIDEO_TEGRA_TPG))
-		fmts_bitmap = chan->fmts_bitmap;
+	const struct tegra_vi_soc *soc = chan->vi->soc;
 
-	if (f->index >= bitmap_weight(fmts_bitmap, MAX_FORMAT_NUM))
+	if (f->index >= soc->nformats)
 		return -EINVAL;
 
-	for (i = 0; i < f->index + 1; i++, index++)
-		index = find_next_bit(fmts_bitmap, MAX_FORMAT_NUM, index);
-
-	f->pixelformat = tegra_get_format_fourcc_by_idx(chan->vi, index - 1);
+	f->pixelformat = soc->video_formats[f->index].fourcc;
 
 	return 0;
 }
@@ -1059,78 +1042,6 @@ static int tegra_channel_setup_ctrl_handler(struct tegra_vi_channel *chan)
 	return 0;
 }
 
-/* VI only support 2 formats in TPG mode */
-static void vi_tpg_fmts_bitmap_init(struct tegra_vi_channel *chan)
-{
-	int index;
-
-	bitmap_zero(chan->tpg_fmts_bitmap, MAX_FORMAT_NUM);
-
-	index = tegra_get_format_idx_by_code(chan->vi,
-					     MEDIA_BUS_FMT_SRGGB10_1X10, 0);
-	bitmap_set(chan->tpg_fmts_bitmap, index, 1);
-
-	index = tegra_get_format_idx_by_code(chan->vi,
-					     MEDIA_BUS_FMT_RGB888_1X32_PADHI,
-					     0);
-	bitmap_set(chan->tpg_fmts_bitmap, index, 1);
-}
-
-static int vi_fmts_bitmap_init(struct tegra_vi_channel *chan)
-{
-	int index, ret, match_code = 0;
-	struct v4l2_subdev *subdev;
-	struct v4l2_subdev_mbus_code_enum code = {
-		.which = V4L2_SUBDEV_FORMAT_ACTIVE,
-	};
-
-	bitmap_zero(chan->fmts_bitmap, MAX_FORMAT_NUM);
-
-	/*
-	 * Set the bitmap bits based on all the matched formats between the
-	 * available media bus formats of sub-device and the pre-defined Tegra
-	 * supported video formats.
-	 */
-	subdev = tegra_channel_get_remote_source_subdev(chan);
-	while (1) {
-		ret = v4l2_subdev_call(subdev, pad, enum_mbus_code,
-				       NULL, &code);
-		if (ret < 0)
-			break;
-
-		index = tegra_get_format_idx_by_code(chan->vi, code.code, 0);
-		while (index >= 0) {
-			bitmap_set(chan->fmts_bitmap, index, 1);
-			if (!match_code)
-				match_code = code.code;
-			/* look for other formats with same mbus code */
-			index = tegra_get_format_idx_by_code(chan->vi,
-							     code.code,
-							     index + 1);
-		}
-
-		code.index++;
-	}
-
-	/*
-	 * Set the bitmap bit corresponding to default tegra video format if
-	 * there are no matched formats.
-	 */
-	if (!match_code) {
-		match_code = tegra_default_format.code;
-		index = tegra_get_format_idx_by_code(chan->vi, match_code, 0);
-		if (WARN_ON(index < 0))
-			return -EINVAL;
-
-		bitmap_set(chan->fmts_bitmap, index, 1);
-	}
-
-	/* initialize channel format to the sub-device active format */
-	tegra_channel_set_subdev_active_fmt(chan);
-
-	return 0;
-}
-
 static void tegra_channel_host1x_syncpts_free(struct tegra_vi_channel *chan)
 {
 	int i;
@@ -1501,7 +1412,6 @@ int tegra_v4l2_nodes_setup_tpg(struct tegra_video_device *vid)
 			goto cleanup;
 
 		v4l2_set_subdev_hostdata(&csi_chan->subdev, vi_chan);
-		vi_tpg_fmts_bitmap_init(vi_chan);
 		csi_chan = list_next_entry(csi_chan, list);
 	}
 
@@ -1721,13 +1631,6 @@ static int tegra_vi_graph_notify_complete(struct v4l2_async_notifier *notifier)
 		goto unregister_video;
 	}
 
-	ret = vi_fmts_bitmap_init(chan);
-	if (ret < 0) {
-		dev_err(vi->dev,
-			"failed to initialize formats bitmap: %d\n", ret);
-		goto unregister_video;
-	}
-
 	subdev = tegra_channel_get_remote_csi_subdev(chan);
 	if (!subdev) {
 		ret = -ENODEV;
diff --git a/drivers/staging/media/tegra-video/vi.h b/drivers/staging/media/tegra-video/vi.h
index a68e2c02c7b0..183796c8a46a 100644
--- a/drivers/staging/media/tegra-video/vi.h
+++ b/drivers/staging/media/tegra-video/vi.h
@@ -163,8 +163,6 @@ struct tegra_vi_graph_entity {
  *
  * @ctrl_handler: V4L2 control handler of this video channel
  * @syncpt_timeout_retry: syncpt timeout retry count for the capture
- * @fmts_bitmap: a bitmap for supported formats matching v4l2 subdev formats
- * @tpg_fmts_bitmap: a bitmap for supported TPG formats
  * @pg_mode: test pattern generator mode (disabled/direct/patch)
  * @notifier: V4L2 asynchronous subdevs notifier
  */
@@ -205,8 +203,6 @@ struct tegra_vi_channel {
 
 	struct v4l2_ctrl_handler ctrl_handler;
 	unsigned int syncpt_timeout_retry;
-	DECLARE_BITMAP(fmts_bitmap, MAX_FORMAT_NUM);
-	DECLARE_BITMAP(tpg_fmts_bitmap, MAX_FORMAT_NUM);
 	enum tegra_vi_pg_mode pg_mode;
 
 	struct v4l2_async_notifier notifier;
-- 
2.34.1

Re: [RESEND PATCH v4 03/21] staging: media: tegra-video: fix .vidioc_enum_fmt_vid_cap to return all formats

[Hans Verkuil]

Hi Luca,

I finally found the time to test this series. It looks OK, except for this patch.
The list of supported formats really has to be the intersection of what the tegra
supports and what the sensor supports.

Otherwise you would advertise pixelformats that cannot be used, and the application
would have no way of knowing that.

This patch needs to be dropped.

I'll run this series through my other checks, and I will let you know today if
anything else needs to be changed.

Regards,

	Hans

On 09/03/2023 15:43, Luca Ceresoli wrote:
> The .vidioc_enum_fmt_vid_cap (called tegra_channel_enum_format() here)
> should return all the supported formats. Instead the current implementation
> computes the intersection between the formats it supports and those
> supported by the first subdev in the stream (typically the image sensor).
> 
> Remove all the unnecessary logic that supports such algorithm. In order to
> do this, also change the Tegra210 CSI TPG formats from the current
> open-coded implementation in vi_tpg_fmts_bitmap_init() to a const array in
> tegra210.c, just like the one that describes the regular formats.
> 
> Fixes: 3d8a97eabef0 ("media: tegra-video: Add Tegra210 Video input driver")
> Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
> Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
> 
> ---
> 
> Changed in v4:
>  - Added review tags
> 
> No changes in v3
> No changes in v2
> ---
>  drivers/staging/media/tegra-video/tegra210.c |   7 +-
>  drivers/staging/media/tegra-video/vi.c       | 103 +------------------
>  drivers/staging/media/tegra-video/vi.h       |   4 -
>  3 files changed, 9 insertions(+), 105 deletions(-)
> 
> diff --git a/drivers/staging/media/tegra-video/tegra210.c b/drivers/staging/media/tegra-video/tegra210.c
> index d58370a84737..eb19dd5107ce 100644
> --- a/drivers/staging/media/tegra-video/tegra210.c
> +++ b/drivers/staging/media/tegra-video/tegra210.c
> @@ -683,8 +683,12 @@ enum tegra210_image_format {
>  	V4L2_PIX_FMT_##FOURCC,						\
>  }
>  
> -/* Tegra210 supported video formats */
>  static const struct tegra_video_format tegra210_video_formats[] = {
> +#if IS_ENABLED(CONFIG_VIDEO_TEGRA_TPG)
> +	/* VI only support 2 formats in TPG mode */
> +	TEGRA210_VIDEO_FMT(RAW10,  10, SRGGB10_1X10,      2, T_R16_I,    SRGGB10),
> +	TEGRA210_VIDEO_FMT(RGB888, 24, RGB888_1X32_PADHI, 4, T_A8B8G8R8, RGBX32),
> +#else
>  	/* RAW 8 */
>  	TEGRA210_VIDEO_FMT(RAW8, 8, SRGGB8_1X8, 1, T_L8, SRGGB8),
>  	TEGRA210_VIDEO_FMT(RAW8, 8, SGRBG8_1X8, 1, T_L8, SGRBG8),
> @@ -714,6 +718,7 @@ static const struct tegra_video_format tegra210_video_formats[] = {
>  	TEGRA210_VIDEO_FMT(YUV422_8, 16, VYUY8_2X8, 2, T_V8_Y8__U8_Y8, YUYV),
>  	TEGRA210_VIDEO_FMT(YUV422_8, 16, YUYV8_2X8, 2, T_Y8_U8__Y8_V8, VYUY),
>  	TEGRA210_VIDEO_FMT(YUV422_8, 16, YVYU8_2X8, 2, T_Y8_V8__Y8_U8, UYVY),
> +#endif
>  };
>  
>  /* Tegra210 VI operations */
> diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
> index 11dd142c98c5..9dba6e97ebdd 100644
> --- a/drivers/staging/media/tegra-video/vi.c
> +++ b/drivers/staging/media/tegra-video/vi.c
> @@ -3,7 +3,6 @@
>   * Copyright (C) 2020 NVIDIA CORPORATION.  All rights reserved.
>   */
>  
> -#include <linux/bitmap.h>
>  #include <linux/clk.h>
>  #include <linux/delay.h>
>  #include <linux/host1x.h>
> @@ -73,15 +72,6 @@ static int tegra_get_format_idx_by_code(struct tegra_vi *vi,
>  	return -1;
>  }
>  
> -static u32 tegra_get_format_fourcc_by_idx(struct tegra_vi *vi,
> -					  unsigned int index)
> -{
> -	if (index >= vi->soc->nformats)
> -		return -EINVAL;
> -
> -	return vi->soc->video_formats[index].fourcc;
> -}
> -
>  static const struct tegra_video_format *
>  tegra_get_format_by_fourcc(struct tegra_vi *vi, u32 fourcc)
>  {
> @@ -430,19 +420,12 @@ static int tegra_channel_enum_format(struct file *file, void *fh,
>  				     struct v4l2_fmtdesc *f)
>  {
>  	struct tegra_vi_channel *chan = video_drvdata(file);
> -	unsigned int index = 0, i;
> -	unsigned long *fmts_bitmap = chan->tpg_fmts_bitmap;
> -
> -	if (!IS_ENABLED(CONFIG_VIDEO_TEGRA_TPG))
> -		fmts_bitmap = chan->fmts_bitmap;
> +	const struct tegra_vi_soc *soc = chan->vi->soc;
>  
> -	if (f->index >= bitmap_weight(fmts_bitmap, MAX_FORMAT_NUM))
> +	if (f->index >= soc->nformats)
>  		return -EINVAL;
>  
> -	for (i = 0; i < f->index + 1; i++, index++)
> -		index = find_next_bit(fmts_bitmap, MAX_FORMAT_NUM, index);
> -
> -	f->pixelformat = tegra_get_format_fourcc_by_idx(chan->vi, index - 1);
> +	f->pixelformat = soc->video_formats[f->index].fourcc;
>  
>  	return 0;
>  }
> @@ -1059,78 +1042,6 @@ static int tegra_channel_setup_ctrl_handler(struct tegra_vi_channel *chan)
>  	return 0;
>  }
>  
> -/* VI only support 2 formats in TPG mode */
> -static void vi_tpg_fmts_bitmap_init(struct tegra_vi_channel *chan)
> -{
> -	int index;
> -
> -	bitmap_zero(chan->tpg_fmts_bitmap, MAX_FORMAT_NUM);
> -
> -	index = tegra_get_format_idx_by_code(chan->vi,
> -					     MEDIA_BUS_FMT_SRGGB10_1X10, 0);
> -	bitmap_set(chan->tpg_fmts_bitmap, index, 1);
> -
> -	index = tegra_get_format_idx_by_code(chan->vi,
> -					     MEDIA_BUS_FMT_RGB888_1X32_PADHI,
> -					     0);
> -	bitmap_set(chan->tpg_fmts_bitmap, index, 1);
> -}
> -
> -static int vi_fmts_bitmap_init(struct tegra_vi_channel *chan)
> -{
> -	int index, ret, match_code = 0;
> -	struct v4l2_subdev *subdev;
> -	struct v4l2_subdev_mbus_code_enum code = {
> -		.which = V4L2_SUBDEV_FORMAT_ACTIVE,
> -	};
> -
> -	bitmap_zero(chan->fmts_bitmap, MAX_FORMAT_NUM);
> -
> -	/*
> -	 * Set the bitmap bits based on all the matched formats between the
> -	 * available media bus formats of sub-device and the pre-defined Tegra
> -	 * supported video formats.
> -	 */
> -	subdev = tegra_channel_get_remote_source_subdev(chan);
> -	while (1) {
> -		ret = v4l2_subdev_call(subdev, pad, enum_mbus_code,
> -				       NULL, &code);
> -		if (ret < 0)
> -			break;
> -
> -		index = tegra_get_format_idx_by_code(chan->vi, code.code, 0);
> -		while (index >= 0) {
> -			bitmap_set(chan->fmts_bitmap, index, 1);
> -			if (!match_code)
> -				match_code = code.code;
> -			/* look for other formats with same mbus code */
> -			index = tegra_get_format_idx_by_code(chan->vi,
> -							     code.code,
> -							     index + 1);
> -		}
> -
> -		code.index++;
> -	}
> -
> -	/*
> -	 * Set the bitmap bit corresponding to default tegra video format if
> -	 * there are no matched formats.
> -	 */
> -	if (!match_code) {
> -		match_code = tegra_default_format.code;
> -		index = tegra_get_format_idx_by_code(chan->vi, match_code, 0);
> -		if (WARN_ON(index < 0))
> -			return -EINVAL;
> -
> -		bitmap_set(chan->fmts_bitmap, index, 1);
> -	}
> -
> -	/* initialize channel format to the sub-device active format */
> -	tegra_channel_set_subdev_active_fmt(chan);
> -
> -	return 0;
> -}
> -
>  static void tegra_channel_host1x_syncpts_free(struct tegra_vi_channel *chan)
>  {
>  	int i;
> @@ -1501,7 +1412,6 @@ int tegra_v4l2_nodes_setup_tpg(struct tegra_video_device *vid)
>  			goto cleanup;
>  
>  		v4l2_set_subdev_hostdata(&csi_chan->subdev, vi_chan);
> -		vi_tpg_fmts_bitmap_init(vi_chan);
>  		csi_chan = list_next_entry(csi_chan, list);
>  	}
>  
> @@ -1721,13 +1631,6 @@ static int tegra_vi_graph_notify_complete(struct v4l2_async_notifier *notifier)
>  		goto unregister_video;
>  	}
>  
> -	ret = vi_fmts_bitmap_init(chan);
> -	if (ret < 0) {
> -		dev_err(vi->dev,
> -			"failed to initialize formats bitmap: %d\n", ret);
> -		goto unregister_video;
> -	}
> -
>  	subdev = tegra_channel_get_remote_csi_subdev(chan);
>  	if (!subdev) {
>  		ret = -ENODEV;
> diff --git a/drivers/staging/media/tegra-video/vi.h b/drivers/staging/media/tegra-video/vi.h
> index a68e2c02c7b0..183796c8a46a 100644
> --- a/drivers/staging/media/tegra-video/vi.h
> +++ b/drivers/staging/media/tegra-video/vi.h
> @@ -163,8 +163,6 @@ struct tegra_vi_graph_entity {
>   *
>   * @ctrl_handler: V4L2 control handler of this video channel
>   * @syncpt_timeout_retry: syncpt timeout retry count for the capture
> - * @fmts_bitmap: a bitmap for supported formats matching v4l2 subdev formats
> - * @tpg_fmts_bitmap: a bitmap for supported TPG formats
>   * @pg_mode: test pattern generator mode (disabled/direct/patch)
>   * @notifier: V4L2 asynchronous subdevs notifier
>   */
> @@ -205,8 +203,6 @@ struct tegra_vi_channel {
>  
>  	struct v4l2_ctrl_handler ctrl_handler;
>  	unsigned int syncpt_timeout_retry;
> -	DECLARE_BITMAP(fmts_bitmap, MAX_FORMAT_NUM);
> -	DECLARE_BITMAP(tpg_fmts_bitmap, MAX_FORMAT_NUM);
>  	enum tegra_vi_pg_mode pg_mode;
>  
>  	struct v4l2_async_notifier notifier;

Re: [RESEND PATCH v4 03/21] staging: media: tegra-video: fix .vidioc_enum_fmt_vid_cap to return all formats

[Hans Verkuil]

Hi Luca,

On 29/03/2023 13:16, Hans Verkuil wrote:
> Hi Luca,
> 
> I finally found the time to test this series. It looks OK, except for this patch.
> The list of supported formats really has to be the intersection of what the tegra
> supports and what the sensor supports.
> 
> Otherwise you would advertise pixelformats that cannot be used, and the application
> would have no way of knowing that.
> 
> This patch needs to be dropped.
> 
> I'll run this series through my other checks, and I will let you know today if
> anything else needs to be changed.

All other checks passed, so this is the only issue blocking this series from being
merged.

Regards,

	Hans

> 
> Regards,
> 
> 	Hans
> 
> On 09/03/2023 15:43, Luca Ceresoli wrote:
>> The .vidioc_enum_fmt_vid_cap (called tegra_channel_enum_format() here)
>> should return all the supported formats. Instead the current implementation
>> computes the intersection between the formats it supports and those
>> supported by the first subdev in the stream (typically the image sensor).
>>
>> Remove all the unnecessary logic that supports such algorithm. In order to
>> do this, also change the Tegra210 CSI TPG formats from the current
>> open-coded implementation in vi_tpg_fmts_bitmap_init() to a const array in
>> tegra210.c, just like the one that describes the regular formats.
>>
>> Fixes: 3d8a97eabef0 ("media: tegra-video: Add Tegra210 Video input driver")
>> Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
>> Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
>>
>> ---
>>
>> Changed in v4:
>>  - Added review tags
>>
>> No changes in v3
>> No changes in v2
>> ---
>>  drivers/staging/media/tegra-video/tegra210.c |   7 +-
>>  drivers/staging/media/tegra-video/vi.c       | 103 +------------------
>>  drivers/staging/media/tegra-video/vi.h       |   4 -
>>  3 files changed, 9 insertions(+), 105 deletions(-)
>>
>> diff --git a/drivers/staging/media/tegra-video/tegra210.c b/drivers/staging/media/tegra-video/tegra210.c
>> index d58370a84737..eb19dd5107ce 100644
>> --- a/drivers/staging/media/tegra-video/tegra210.c
>> +++ b/drivers/staging/media/tegra-video/tegra210.c
>> @@ -683,8 +683,12 @@ enum tegra210_image_format {
>>  	V4L2_PIX_FMT_##FOURCC,						\
>>  }
>>  
>> -/* Tegra210 supported video formats */
>>  static const struct tegra_video_format tegra210_video_formats[] = {
>> +#if IS_ENABLED(CONFIG_VIDEO_TEGRA_TPG)
>> +	/* VI only support 2 formats in TPG mode */
>> +	TEGRA210_VIDEO_FMT(RAW10,  10, SRGGB10_1X10,      2, T_R16_I,    SRGGB10),
>> +	TEGRA210_VIDEO_FMT(RGB888, 24, RGB888_1X32_PADHI, 4, T_A8B8G8R8, RGBX32),
>> +#else
>>  	/* RAW 8 */
>>  	TEGRA210_VIDEO_FMT(RAW8, 8, SRGGB8_1X8, 1, T_L8, SRGGB8),
>>  	TEGRA210_VIDEO_FMT(RAW8, 8, SGRBG8_1X8, 1, T_L8, SGRBG8),
>> @@ -714,6 +718,7 @@ static const struct tegra_video_format tegra210_video_formats[] = {
>>  	TEGRA210_VIDEO_FMT(YUV422_8, 16, VYUY8_2X8, 2, T_V8_Y8__U8_Y8, YUYV),
>>  	TEGRA210_VIDEO_FMT(YUV422_8, 16, YUYV8_2X8, 2, T_Y8_U8__Y8_V8, VYUY),
>>  	TEGRA210_VIDEO_FMT(YUV422_8, 16, YVYU8_2X8, 2, T_Y8_V8__Y8_U8, UYVY),
>> +#endif
>>  };
>>  
>>  /* Tegra210 VI operations */
>> diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
>> index 11dd142c98c5..9dba6e97ebdd 100644
>> --- a/drivers/staging/media/tegra-video/vi.c
>> +++ b/drivers/staging/media/tegra-video/vi.c
>> @@ -3,7 +3,6 @@
>>   * Copyright (C) 2020 NVIDIA CORPORATION.  All rights reserved.
>>   */
>>  
>> -#include <linux/bitmap.h>
>>  #include <linux/clk.h>
>>  #include <linux/delay.h>
>>  #include <linux/host1x.h>
>> @@ -73,15 +72,6 @@ static int tegra_get_format_idx_by_code(struct tegra_vi *vi,
>>  	return -1;
>>  }
>>  
>> -static u32 tegra_get_format_fourcc_by_idx(struct tegra_vi *vi,
>> -					  unsigned int index)
>> -{
>> -	if (index >= vi->soc->nformats)
>> -		return -EINVAL;
>> -
>> -	return vi->soc->video_formats[index].fourcc;
>> -}
>> -
>>  static const struct tegra_video_format *
>>  tegra_get_format_by_fourcc(struct tegra_vi *vi, u32 fourcc)
>>  {
>> @@ -430,19 +420,12 @@ static int tegra_channel_enum_format(struct file *file, void *fh,
>>  				     struct v4l2_fmtdesc *f)
>>  {
>>  	struct tegra_vi_channel *chan = video_drvdata(file);
>> -	unsigned int index = 0, i;
>> -	unsigned long *fmts_bitmap = chan->tpg_fmts_bitmap;
>> -
>> -	if (!IS_ENABLED(CONFIG_VIDEO_TEGRA_TPG))
>> -		fmts_bitmap = chan->fmts_bitmap;
>> +	const struct tegra_vi_soc *soc = chan->vi->soc;
>>  
>> -	if (f->index >= bitmap_weight(fmts_bitmap, MAX_FORMAT_NUM))
>> +	if (f->index >= soc->nformats)
>>  		return -EINVAL;
>>  
>> -	for (i = 0; i < f->index + 1; i++, index++)
>> -		index = find_next_bit(fmts_bitmap, MAX_FORMAT_NUM, index);
>> -
>> -	f->pixelformat = tegra_get_format_fourcc_by_idx(chan->vi, index - 1);
>> +	f->pixelformat = soc->video_formats[f->index].fourcc;
>>  
>>  	return 0;
>>  }
>> @@ -1059,78 +1042,6 @@ static int tegra_channel_setup_ctrl_handler(struct tegra_vi_channel *chan)
>>  	return 0;
>>  }
>>  
>> -/* VI only support 2 formats in TPG mode */
>> -static void vi_tpg_fmts_bitmap_init(struct tegra_vi_channel *chan)
>> -{
>> -	int index;
>> -
>> -	bitmap_zero(chan->tpg_fmts_bitmap, MAX_FORMAT_NUM);
>> -
>> -	index = tegra_get_format_idx_by_code(chan->vi,
>> -					     MEDIA_BUS_FMT_SRGGB10_1X10, 0);
>> -	bitmap_set(chan->tpg_fmts_bitmap, index, 1);
>> -
>> -	index = tegra_get_format_idx_by_code(chan->vi,
>> -					     MEDIA_BUS_FMT_RGB888_1X32_PADHI,
>> -					     0);
>> -	bitmap_set(chan->tpg_fmts_bitmap, index, 1);
>> -}
>> -
>> -static int vi_fmts_bitmap_init(struct tegra_vi_channel *chan)
>> -{
>> -	int index, ret, match_code = 0;
>> -	struct v4l2_subdev *subdev;
>> -	struct v4l2_subdev_mbus_code_enum code = {
>> -		.which = V4L2_SUBDEV_FORMAT_ACTIVE,
>> -	};
>> -
>> -	bitmap_zero(chan->fmts_bitmap, MAX_FORMAT_NUM);
>> -
>> -	/*
>> -	 * Set the bitmap bits based on all the matched formats between the
>> -	 * available media bus formats of sub-device and the pre-defined Tegra
>> -	 * supported video formats.
>> -	 */
>> -	subdev = tegra_channel_get_remote_source_subdev(chan);
>> -	while (1) {
>> -		ret = v4l2_subdev_call(subdev, pad, enum_mbus_code,
>> -				       NULL, &code);
>> -		if (ret < 0)
>> -			break;
>> -
>> -		index = tegra_get_format_idx_by_code(chan->vi, code.code, 0);
>> -		while (index >= 0) {
>> -			bitmap_set(chan->fmts_bitmap, index, 1);
>> -			if (!match_code)
>> -				match_code = code.code;
>> -			/* look for other formats with same mbus code */
>> -			index = tegra_get_format_idx_by_code(chan->vi,
>> -							     code.code,
>> -							     index + 1);
>> -		}
>> -
>> -		code.index++;
>> -	}
>> -
>> -	/*
>> -	 * Set the bitmap bit corresponding to default tegra video format if
>> -	 * there are no matched formats.
>> -	 */
>> -	if (!match_code) {
>> -		match_code = tegra_default_format.code;
>> -		index = tegra_get_format_idx_by_code(chan->vi, match_code, 0);
>> -		if (WARN_ON(index < 0))
>> -			return -EINVAL;
>> -
>> -		bitmap_set(chan->fmts_bitmap, index, 1);
>> -	}
>> -
>> -	/* initialize channel format to the sub-device active format */
>> -	tegra_channel_set_subdev_active_fmt(chan);
>> -
>> -	return 0;
>> -}
>> -
>>  static void tegra_channel_host1x_syncpts_free(struct tegra_vi_channel *chan)
>>  {
>>  	int i;
>> @@ -1501,7 +1412,6 @@ int tegra_v4l2_nodes_setup_tpg(struct tegra_video_device *vid)
>>  			goto cleanup;
>>  
>>  		v4l2_set_subdev_hostdata(&csi_chan->subdev, vi_chan);
>> -		vi_tpg_fmts_bitmap_init(vi_chan);
>>  		csi_chan = list_next_entry(csi_chan, list);
>>  	}
>>  
>> @@ -1721,13 +1631,6 @@ static int tegra_vi_graph_notify_complete(struct v4l2_async_notifier *notifier)
>>  		goto unregister_video;
>>  	}
>>  
>> -	ret = vi_fmts_bitmap_init(chan);
>> -	if (ret < 0) {
>> -		dev_err(vi->dev,
>> -			"failed to initialize formats bitmap: %d\n", ret);
>> -		goto unregister_video;
>> -	}
>> -
>>  	subdev = tegra_channel_get_remote_csi_subdev(chan);
>>  	if (!subdev) {
>>  		ret = -ENODEV;
>> diff --git a/drivers/staging/media/tegra-video/vi.h b/drivers/staging/media/tegra-video/vi.h
>> index a68e2c02c7b0..183796c8a46a 100644
>> --- a/drivers/staging/media/tegra-video/vi.h
>> +++ b/drivers/staging/media/tegra-video/vi.h
>> @@ -163,8 +163,6 @@ struct tegra_vi_graph_entity {
>>   *
>>   * @ctrl_handler: V4L2 control handler of this video channel
>>   * @syncpt_timeout_retry: syncpt timeout retry count for the capture
>> - * @fmts_bitmap: a bitmap for supported formats matching v4l2 subdev formats
>> - * @tpg_fmts_bitmap: a bitmap for supported TPG formats
>>   * @pg_mode: test pattern generator mode (disabled/direct/patch)
>>   * @notifier: V4L2 asynchronous subdevs notifier
>>   */
>> @@ -205,8 +203,6 @@ struct tegra_vi_channel {
>>  
>>  	struct v4l2_ctrl_handler ctrl_handler;
>>  	unsigned int syncpt_timeout_retry;
>> -	DECLARE_BITMAP(fmts_bitmap, MAX_FORMAT_NUM);
>> -	DECLARE_BITMAP(tpg_fmts_bitmap, MAX_FORMAT_NUM);
>>  	enum tegra_vi_pg_mode pg_mode;
>>  
>>  	struct v4l2_async_notifier notifier;
> 

Re: [RESEND PATCH v4 03/21] staging: media: tegra-video: fix .vidioc_enum_fmt_vid_cap to return all formats

[Luca Ceresoli]

Hello Hans,

On Wed, 29 Mar 2023 13:16:22 +0200
Hans Verkuil <hverkuil-cisco@xs4all.nl> wrote:

> Hi Luca,
> 
> I finally found the time to test this series. It looks OK, except for this patch.

Thank you very much for taking the time!

> The list of supported formats really has to be the intersection of what the tegra
> supports and what the sensor supports.
> 
> Otherwise you would advertise pixelformats that cannot be used, and the application
> would have no way of knowing that.

As far as I understand, I think we should rather make this driver fully
behave as an MC-centric device. It is already using MC quite
successfully after all.

Do you think this is correct?

If you do, then I think the plan would be:

 - Add the V4L2_CAP_IO_MC flag
 - As the mbus_code in get_format appropriately
 - Leave the changes in this patch unmodified otherwise

Best regards,
Luca

-- 
Luca Ceresoli, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

Re: [RESEND PATCH v4 03/21] staging: media: tegra-video: fix .vidioc_enum_fmt_vid_cap to return all formats

[Laurent Pinchart]

Hi Luca,

On Tue, Apr 04, 2023 at 04:12:51PM +0200, Luca Ceresoli wrote:
> On Wed, 29 Mar 2023 13:16:22 +0200 Hans Verkuil wrote:
> 
> > Hi Luca,
> > 
> > I finally found the time to test this series. It looks OK, except for this patch.
> 
> Thank you very much for taking the time!
> 
> > The list of supported formats really has to be the intersection of what the tegra
> > supports and what the sensor supports.
> > 
> > Otherwise you would advertise pixelformats that cannot be used, and the application
> > would have no way of knowing that.
> 
> As far as I understand, I think we should rather make this driver fully
> behave as an MC-centric device. It is already using MC quite
> successfully after all.
> 
> Do you think this is correct?

Given the use cases for this driver, I agree.

> If you do, then I think the plan would be:
> 
>  - Add the V4L2_CAP_IO_MC flag
>  - As the mbus_code in get_format appropriately
>  - Leave the changes in this patch unmodified otherwise

-- 
Regards,

Laurent Pinchart

Re: [RESEND PATCH v4 03/21] staging: media: tegra-video: fix .vidioc_enum_fmt_vid_cap to return all formats

[Luca Ceresoli]

Hi Laurent,

On Wed, 5 Apr 2023 05:30:48 +0300
Laurent Pinchart <laurent.pinchart@ideasonboard.com> wrote:

> Hi Luca,
> 
> On Tue, Apr 04, 2023 at 04:12:51PM +0200, Luca Ceresoli wrote:
> > On Wed, 29 Mar 2023 13:16:22 +0200 Hans Verkuil wrote:
> >   
> > > Hi Luca,
> > > 
> > > I finally found the time to test this series. It looks OK, except for this patch.  
> > 
> > Thank you very much for taking the time!
> >   
> > > The list of supported formats really has to be the intersection of what the tegra
> > > supports and what the sensor supports.
> > > 
> > > Otherwise you would advertise pixelformats that cannot be used, and the application
> > > would have no way of knowing that.  
> > 
> > As far as I understand, I think we should rather make this driver fully
> > behave as an MC-centric device. It is already using MC quite
> > successfully after all.
> > 
> > Do you think this is correct?  
> 
> Given the use cases for this driver, I agree.

Ok, thanks for the feedback. I will send a v5 with this change.

Best regards,
Luca

-- 
Luca Ceresoli, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

Re: [RESEND PATCH v4 03/21] staging: media: tegra-video: fix .vidioc_enum_fmt_vid_cap to return all formats

[Hans Verkuil]

On 05/04/2023 10:31, Luca Ceresoli wrote:
> Hi Laurent,
> 
> On Wed, 5 Apr 2023 05:30:48 +0300
> Laurent Pinchart <laurent.pinchart@ideasonboard.com> wrote:
> 
>> Hi Luca,
>>
>> On Tue, Apr 04, 2023 at 04:12:51PM +0200, Luca Ceresoli wrote:
>>> On Wed, 29 Mar 2023 13:16:22 +0200 Hans Verkuil wrote:
>>>   
>>>> Hi Luca,
>>>>
>>>> I finally found the time to test this series. It looks OK, except for this patch.  
>>>
>>> Thank you very much for taking the time!
>>>   
>>>> The list of supported formats really has to be the intersection of what the tegra
>>>> supports and what the sensor supports.
>>>>
>>>> Otherwise you would advertise pixelformats that cannot be used, and the application
>>>> would have no way of knowing that.  
>>>
>>> As far as I understand, I think we should rather make this driver fully
>>> behave as an MC-centric device. It is already using MC quite
>>> successfully after all.
>>>
>>> Do you think this is correct?  
>>
>> Given the use cases for this driver, I agree.

I disagree.

This driver doesn't use the media controller for anything at the moment. The
/dev/mediaX device just shows the internal topology (i.e. connected sensors),
but otherwise it does nothing.

While it would be great if we could unlock the ISP on the Tegra, the reality
is that it is entirely closed source and can't be used in a linux driver, and
that's not going to change, sadly.

That leaves us with just a basic CSI capture driver. Rather than trying to
change this driver to a full MC device with no benefits, just drop this change
and get your code in.

Note that this driver will stay in staging since it still fails when I try to
capture from two sensors at the same time: syncpoint errors start appearing
in that case. I think there are locking issues. I think I have someone to take
a look at that, but first I want your series to get merged.

In the very unlikely event that the ISP can be implemented in a linux driver,
it will probably become a new driver.

Regards,

	Hans

> 
> Ok, thanks for the feedback. I will send a v5 with this change.
> 
> Best regards,
> Luca
> 

Re: [RESEND PATCH v4 03/21] staging: media: tegra-video: fix .vidioc_enum_fmt_vid_cap to return all formats

[Thierry Reding]

[-- Attachment #1: Type: text/plain, Size: 748 bytes --]

On Wed, Apr 05, 2023 at 10:50:37AM +0200, Hans Verkuil wrote:
[...]
> Note that this driver will stay in staging since it still fails when I try to
> capture from two sensors at the same time: syncpoint errors start appearing
> in that case. I think there are locking issues. I think I have someone to take
> a look at that, but first I want your series to get merged.

Mikko (added) is familiar with syncpoints, so he may be able to help
with. Can you provide steps to reproduce these issues? That may make
it easier for us to help figure this out.

Unfortunately I don't have any device with an actual sensor on it, so
I can only test with the test pattern generator, but syncpoint errors
sound like they would happen with either setup.

Thierry

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

Re: [RESEND PATCH v4 03/21] staging: media: tegra-video: fix .vidioc_enum_fmt_vid_cap to return all formats

[Laurent Pinchart]

Hi Hans,

On Wed, Apr 05, 2023 at 10:50:37AM +0200, Hans Verkuil wrote:
> On 05/04/2023 10:31, Luca Ceresoli wrote:
> > On Wed, 5 Apr 2023 05:30:48 +0300 Laurent Pinchart wrote:
> >> On Tue, Apr 04, 2023 at 04:12:51PM +0200, Luca Ceresoli wrote:
> >>> On Wed, 29 Mar 2023 13:16:22 +0200 Hans Verkuil wrote:
> >>>   
> >>>> Hi Luca,
> >>>>
> >>>> I finally found the time to test this series. It looks OK, except for this patch.  
> >>>
> >>> Thank you very much for taking the time!
> >>>   
> >>>> The list of supported formats really has to be the intersection of what the tegra
> >>>> supports and what the sensor supports.
> >>>>
> >>>> Otherwise you would advertise pixelformats that cannot be used, and the application
> >>>> would have no way of knowing that.  
> >>>
> >>> As far as I understand, I think we should rather make this driver fully
> >>> behave as an MC-centric device. It is already using MC quite
> >>> successfully after all.
> >>>
> >>> Do you think this is correct?  
> >>
> >> Given the use cases for this driver, I agree.
> 
> I disagree.
> 
> This driver doesn't use the media controller for anything at the moment. The
> /dev/mediaX device just shows the internal topology (i.e. connected sensors),
> but otherwise it does nothing.
> 
> While it would be great if we could unlock the ISP on the Tegra, the reality
> is that it is entirely closed source and can't be used in a linux driver, and
> that's not going to change, sadly.

Never say never :-)

> That leaves us with just a basic CSI capture driver. Rather than trying to
> change this driver to a full MC device with no benefits, just drop this change
> and get your code in.

Can't the hardware support capturing different virtual channels or data
types from the same CSI-2 source ? That would require MC support, the
stream API requires subdev device nodes.

> Note that this driver will stay in staging since it still fails when I try to
> capture from two sensors at the same time: syncpoint errors start appearing
> in that case. I think there are locking issues. I think I have someone to take
> a look at that, but first I want your series to get merged.
> 
> In the very unlikely event that the ISP can be implemented in a linux driver,
> it will probably become a new driver.
> 
> Regards,
> 
> > Ok, thanks for the feedback. I will send a v5 with this change.

-- 
Regards,

Laurent Pinchart

[RESEND PATCH v4 04/21] staging: media: tegra-video: improve documentation of tegra_video_format fields

[Luca Ceresoli]

Some fields are irrelevant for Tegra20/VIP. Add a note to clarify that.

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>

---

Changed in v4:
 - Added review tags

No changes in v3
No changes in v2
---
 drivers/staging/media/tegra-video/vi.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/media/tegra-video/vi.h b/drivers/staging/media/tegra-video/vi.h
index 183796c8a46a..dd35c3ac992b 100644
--- a/drivers/staging/media/tegra-video/vi.h
+++ b/drivers/staging/media/tegra-video/vi.h
@@ -256,11 +256,11 @@ enum tegra_image_dt {
 /**
  * struct tegra_video_format - Tegra video format description
  *
- * @img_dt: image data type
- * @bit_width: format width in bits per component
+ * @img_dt: MIPI CSI-2 data type (for CSI-2 only)
+ * @bit_width: format width in bits per component (for CSI/Tegra210 only)
  * @code: media bus format code
  * @bpp: bytes per pixel (when stored in memory)
- * @img_fmt: image format
+ * @img_fmt: image format (for CSI/Tegra210 only)
  * @fourcc: V4L2 pixel format FCC identifier
  */
 struct tegra_video_format {
-- 
2.34.1

[RESEND PATCH v4 05/21] staging: media: tegra-video: document tegra_channel_get_remote_source_subdev

[Luca Ceresoli]

Clarify what this function does.

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>

---

Changed in v4:
 - Added review tags

No changes in v3
No changes in v2
---
 drivers/staging/media/tegra-video/vi.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index 9dba6e97ebdd..6aecdd28bd82 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -154,6 +154,9 @@ tegra_channel_get_remote_csi_subdev(struct tegra_vi_channel *chan)
 	return media_entity_to_v4l2_subdev(pad->entity);
 }
 
+/*
+ * Walk up the chain until the initial source (e.g. image sensor)
+ */
 struct v4l2_subdev *
 tegra_channel_get_remote_source_subdev(struct tegra_vi_channel *chan)
 {
-- 
2.34.1

[RESEND PATCH v4 06/21] staging: media: tegra-video: fix typos in comment

[Luca Ceresoli]

Add "skip" in "so we can *skip* the current channel" or it doesn't make
sense.

Also add articles where appropriate to fix English grammar.

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>

---

Changed in v4:
 - Added review tags

No changes in v3
No changes in v2
---
 drivers/staging/media/tegra-video/vi.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index 6aecdd28bd82..ae7adf640e76 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -1762,10 +1762,10 @@ static int tegra_vi_graph_init(struct tegra_vi *vi)
 	 * Walk the links to parse the full graph. Each channel will have
 	 * one endpoint of the composite node. Start by parsing the
 	 * composite node and parse the remote entities in turn.
-	 * Each channel will register v4l2 async notifier to make the graph
-	 * independent between the channels so we can the current channel
+	 * Each channel will register a v4l2 async notifier to make the graph
+	 * independent between the channels so we can skip the current channel
 	 * in case of something wrong during graph parsing and continue with
-	 * next channels.
+	 * the next channels.
 	 */
 	list_for_each_entry(chan, &vi->vi_chans, list) {
 		struct fwnode_handle *ep, *remote;
-- 
2.34.1

[RESEND PATCH v4 07/21] staging: media: tegra-video: improve error messages

[Luca Ceresoli]

tegra_vi_channels_alloc() can primarily fail for two reasons:

 1. "ports" node not found
 2. port_num > vi->soc->vi_max_channels

Case 1 prints nothing, case 2 has a dev_err(). The caller [tegra_vi_init()]
has a generic dev_err() on any failure. This mean that in case 2 we print
two messages, and in case 1 we only print a generic message.

Remove the generic message and add a specific message when case 1 happens,
so that we always have one specific message without even increasing the
number of dev_dbg*() calls.

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>

---

Changed in v4:
 - Added review tags

No changes in v3
No changes in v2
---
 drivers/staging/media/tegra-video/vi.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index ae7adf640e76..0e5067a7986a 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -1272,7 +1272,7 @@ static int tegra_vi_channels_alloc(struct tegra_vi *vi)
 
 	ports = of_get_child_by_name(node, "ports");
 	if (!ports)
-		return -ENODEV;
+		return dev_err_probe(vi->dev, -ENODEV, "%pOF: missing 'ports' node\n", node);
 
 	for_each_child_of_node(ports, port) {
 		if (!of_node_name_eq(port, "port"))
@@ -1824,11 +1824,8 @@ static int tegra_vi_init(struct host1x_client *client)
 		ret = tegra_vi_tpg_channels_alloc(vi);
 	else
 		ret = tegra_vi_channels_alloc(vi);
-	if (ret < 0) {
-		dev_err(vi->dev,
-			"failed to allocate vi channels: %d\n", ret);
+	if (ret < 0)
 		goto free_chans;
-	}
 
 	ret = tegra_vi_channels_init(vi);
 	if (ret < 0)
-- 
2.34.1

[RESEND PATCH v4 08/21] staging: media: tegra-video: slightly simplify cleanup on errors

[Luca Ceresoli]

of_node_put(node) does nothing if node == NULL, so it can be moved to the
cleanup section at the bottom.

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>

---

Changed in v4:
 - Added review tags

No changes in v3
No changes in v2
---
 drivers/staging/media/tegra-video/vi.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index 0e5067a7986a..c2724e1ecafb 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -1263,7 +1263,7 @@ static int tegra_vi_channels_alloc(struct tegra_vi *vi)
 	struct device_node *node = vi->dev->of_node;
 	struct device_node *ep = NULL;
 	struct device_node *ports;
-	struct device_node *port;
+	struct device_node *port = NULL;
 	unsigned int port_num;
 	struct device_node *parent;
 	struct v4l2_fwnode_endpoint v4l2_ep = { .bus_type = 0 };
@@ -1286,7 +1286,6 @@ static int tegra_vi_channels_alloc(struct tegra_vi *vi)
 			dev_err(vi->dev, "invalid port num %d for %pOF\n",
 				port_num, port);
 			ret = -EINVAL;
-			of_node_put(port);
 			goto cleanup;
 		}
 
@@ -1309,13 +1308,12 @@ static int tegra_vi_channels_alloc(struct tegra_vi *vi)
 
 		lanes = v4l2_ep.bus.mipi_csi2.num_data_lanes;
 		ret = tegra_vi_channel_alloc(vi, port_num, port, lanes);
-		if (ret < 0) {
-			of_node_put(port);
+		if (ret < 0)
 			goto cleanup;
-		}
 	}
 
 cleanup:
+	of_node_put(port);
 	of_node_put(ports);
 	return ret;
 }
-- 
2.34.1

[RESEND PATCH v4 09/21] staging: media: tegra-video: move private struct declaration to C file

[Luca Ceresoli]

struct tegra_vi_graph_entity is an internal implementation detail of the VI
module. Move its declaration from vi.h to vi.c.

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>

---

Changed in v4:
 - Added review tags

No changes in v3
No changes in v2
---
 drivers/staging/media/tegra-video/vi.c | 13 +++++++++++++
 drivers/staging/media/tegra-video/vi.h | 13 -------------
 2 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index c2724e1ecafb..4e48eaa0fbdc 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -31,6 +31,19 @@
 
 #define MAX_CID_CONTROLS		1
 
+/**
+ * struct tegra_vi_graph_entity - Entity in the video graph
+ *
+ * @asd: subdev asynchronous registration information
+ * @entity: media entity from the corresponding V4L2 subdev
+ * @subdev: V4L2 subdev
+ */
+struct tegra_vi_graph_entity {
+	struct v4l2_async_subdev asd;
+	struct media_entity *entity;
+	struct v4l2_subdev *subdev;
+};
+
 static const struct tegra_video_format tegra_default_format = {
 	.img_dt = TEGRA_IMAGE_DT_RAW10,
 	.bit_width = 10,
diff --git a/drivers/staging/media/tegra-video/vi.h b/drivers/staging/media/tegra-video/vi.h
index dd35c3ac992b..dfd834a69848 100644
--- a/drivers/staging/media/tegra-video/vi.h
+++ b/drivers/staging/media/tegra-video/vi.h
@@ -98,19 +98,6 @@ struct tegra_vi {
 	struct list_head vi_chans;
 };
 
-/**
- * struct tegra_vi_graph_entity - Entity in the video graph
- *
- * @asd: subdev asynchronous registration information
- * @entity: media entity from the corresponding V4L2 subdev
- * @subdev: V4L2 subdev
- */
-struct tegra_vi_graph_entity {
-	struct v4l2_async_subdev asd;
-	struct media_entity *entity;
-	struct v4l2_subdev *subdev;
-};
-
 /**
  * struct tegra_vi_channel - Tegra video channel
  *
-- 
2.34.1

[RESEND PATCH v4 10/21] staging: media: tegra-video: move tegra210_csi_soc to C file

[Luca Ceresoli]

This declaration is used only in csi.c, no need to export it elsewhere.

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>

---

Changed in v4:
 - Added review tags

This patch was added in v3.
---
 drivers/staging/media/tegra-video/csi.c | 4 ++++
 drivers/staging/media/tegra-video/csi.h | 4 ----
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/staging/media/tegra-video/csi.c b/drivers/staging/media/tegra-video/csi.c
index 426e653bd55d..9a03d5ccdf3c 100644
--- a/drivers/staging/media/tegra-video/csi.c
+++ b/drivers/staging/media/tegra-video/csi.c
@@ -792,6 +792,10 @@ static int tegra_csi_remove(struct platform_device *pdev)
 	return 0;
 }
 
+#if defined(CONFIG_ARCH_TEGRA_210_SOC)
+extern const struct tegra_csi_soc tegra210_csi_soc;
+#endif
+
 static const struct of_device_id tegra_csi_of_id_table[] = {
 #if defined(CONFIG_ARCH_TEGRA_210_SOC)
 	{ .compatible = "nvidia,tegra210-csi", .data = &tegra210_csi_soc },
diff --git a/drivers/staging/media/tegra-video/csi.h b/drivers/staging/media/tegra-video/csi.h
index 6960ea2e3d36..3e6e5ee1bb1e 100644
--- a/drivers/staging/media/tegra-video/csi.h
+++ b/drivers/staging/media/tegra-video/csi.h
@@ -151,10 +151,6 @@ struct tegra_csi {
 	struct list_head csi_chans;
 };
 
-#if defined(CONFIG_ARCH_TEGRA_210_SOC)
-extern const struct tegra_csi_soc tegra210_csi_soc;
-#endif
-
 void tegra_csi_error_recover(struct v4l2_subdev *subdev);
 void tegra_csi_calc_settle_time(struct tegra_csi_channel *csi_chan,
 				u8 csi_port_num,
-- 
2.34.1

[RESEND PATCH v4 11/21] staging: media: tegra-video: remove unneeded include

[Luca Ceresoli]

There is only a pointer reference to struct tegra_vi in video.h, thus vi.h
is not needed.

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>

---

Changed in v4:
 - Added review tags

No changes in v3
No changes in v2
---
 drivers/staging/media/tegra-video/video.h | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/staging/media/tegra-video/video.h b/drivers/staging/media/tegra-video/video.h
index fadaf2189dc9..1e9be1474a9c 100644
--- a/drivers/staging/media/tegra-video/video.h
+++ b/drivers/staging/media/tegra-video/video.h
@@ -12,7 +12,6 @@
 #include <media/v4l2-device.h>
 
 #include "vi.h"
-#include "csi.h"
 
 struct tegra_video_device {
 	struct v4l2_device v4l2_dev;
-- 
2.34.1

[RESEND PATCH v4 12/21] staging: media: tegra-video: Kconfig: allow TPG only on Tegra210

[Luca Ceresoli]

We are about to add support for the Tegra20 parallel video capture, which
has no TPG. In preparation for that, limit the VIDEO_TEGRA_TPG option to
Tegra210 which is the only implementation currently provided by this
driver.

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>

---

Changed in v4:
 - Added review tags

No changes in v3
No changes in v2
---
 drivers/staging/media/tegra-video/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/staging/media/tegra-video/Kconfig b/drivers/staging/media/tegra-video/Kconfig
index df1b2cff2417..c53441822fdf 100644
--- a/drivers/staging/media/tegra-video/Kconfig
+++ b/drivers/staging/media/tegra-video/Kconfig
@@ -15,5 +15,6 @@ config VIDEO_TEGRA
 config VIDEO_TEGRA_TPG
 	bool "NVIDIA Tegra VI driver TPG mode"
 	depends on VIDEO_TEGRA
+	depends on ARCH_TEGRA_210_SOC
 	help
 	  Say yes here to enable Tegra internal TPG mode
-- 
2.34.1

[RESEND PATCH v4 13/21] staging: media: tegra-video: move tegra_channel_fmt_align to a per-soc op

[Luca Ceresoli]

tegra_channel_fmt_align() takes care of the size constraints, alignment and
rounding requirements of the Tegra210 VI peripheral. Tegra20 has different
constraints.

In preparation for adding Tegra20 support, move this function to a new op
in the soc-specific `struct tegra_vi_ops` .

Also move to tegra210.c the T210-specific defines used in the moved code.

No functional changes.

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>

---

Changed in v4:
 - Added review tags

No changes in v3
No changes in v2
---
 drivers/staging/media/tegra-video/tegra210.c | 36 ++++++++++++++++++
 drivers/staging/media/tegra-video/vi.c       | 40 +++-----------------
 drivers/staging/media/tegra-video/vi.h       |  9 ++---
 3 files changed, 44 insertions(+), 41 deletions(-)

diff --git a/drivers/staging/media/tegra-video/tegra210.c b/drivers/staging/media/tegra-video/tegra210.c
index eb19dd5107ce..71483d0c19bf 100644
--- a/drivers/staging/media/tegra-video/tegra210.c
+++ b/drivers/staging/media/tegra-video/tegra210.c
@@ -17,6 +17,13 @@
 #include "csi.h"
 #include "vi.h"
 
+#define TEGRA210_MIN_WIDTH	32U
+#define TEGRA210_MAX_WIDTH	32768U
+#define TEGRA210_MIN_HEIGHT	32U
+#define TEGRA210_MAX_HEIGHT	32768U
+
+#define SURFACE_ALIGN_BYTES	64
+
 #define TEGRA_VI_SYNCPT_WAIT_TIMEOUT			msecs_to_jiffies(200)
 
 /* Tegra210 VI registers */
@@ -172,6 +179,34 @@ static u32 vi_csi_read(struct tegra_vi_channel *chan, u8 portno,
 /*
  * Tegra210 VI channel capture operations
  */
+static void tegra210_fmt_align(struct v4l2_pix_format *pix, unsigned int bpp)
+{
+	unsigned int min_bpl;
+	unsigned int max_bpl;
+	unsigned int bpl;
+
+	/*
+	 * The transfer alignment requirements are expressed in bytes.
+	 * Clamp the requested width and height to the limits.
+	 */
+	pix->width = clamp(pix->width, TEGRA210_MIN_WIDTH, TEGRA210_MAX_WIDTH);
+	pix->height = clamp(pix->height, TEGRA210_MIN_HEIGHT, TEGRA210_MAX_HEIGHT);
+
+	/* Clamp the requested bytes per line value. If the maximum bytes per
+	 * line value is zero, the module doesn't support user configurable
+	 * line sizes. Override the requested value with the minimum in that
+	 * case.
+	 */
+	min_bpl = pix->width * bpp;
+	max_bpl = rounddown(TEGRA210_MAX_WIDTH, SURFACE_ALIGN_BYTES);
+	bpl = roundup(pix->bytesperline, SURFACE_ALIGN_BYTES);
+
+	pix->bytesperline = clamp(bpl, min_bpl, max_bpl);
+	pix->sizeimage = pix->bytesperline * pix->height;
+	if (pix->pixelformat == V4L2_PIX_FMT_NV16)
+		pix->sizeimage *= 2;
+}
+
 static int tegra_channel_capture_setup(struct tegra_vi_channel *chan,
 				       u8 portno)
 {
@@ -723,6 +758,7 @@ static const struct tegra_video_format tegra210_video_formats[] = {
 
 /* Tegra210 VI operations */
 static const struct tegra_vi_ops tegra210_vi_ops = {
+	.vi_fmt_align = tegra210_fmt_align,
 	.vi_start_streaming = tegra210_vi_start_streaming,
 	.vi_stop_streaming = tegra210_vi_stop_streaming,
 };
diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index 4e48eaa0fbdc..a76cad0e3026 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -456,36 +456,6 @@ static int tegra_channel_get_format(struct file *file, void *fh,
 	return 0;
 }
 
-static void tegra_channel_fmt_align(struct tegra_vi_channel *chan,
-				    struct v4l2_pix_format *pix,
-				    unsigned int bpp)
-{
-	unsigned int min_bpl;
-	unsigned int max_bpl;
-	unsigned int bpl;
-
-	/*
-	 * The transfer alignment requirements are expressed in bytes.
-	 * Clamp the requested width and height to the limits.
-	 */
-	pix->width = clamp(pix->width, TEGRA_MIN_WIDTH, TEGRA_MAX_WIDTH);
-	pix->height = clamp(pix->height, TEGRA_MIN_HEIGHT, TEGRA_MAX_HEIGHT);
-
-	/* Clamp the requested bytes per line value. If the maximum bytes per
-	 * line value is zero, the module doesn't support user configurable
-	 * line sizes. Override the requested value with the minimum in that
-	 * case.
-	 */
-	min_bpl = pix->width * bpp;
-	max_bpl = rounddown(TEGRA_MAX_WIDTH, SURFACE_ALIGN_BYTES);
-	bpl = roundup(pix->bytesperline, SURFACE_ALIGN_BYTES);
-
-	pix->bytesperline = clamp(bpl, min_bpl, max_bpl);
-	pix->sizeimage = pix->bytesperline * pix->height;
-	if (pix->pixelformat == V4L2_PIX_FMT_NV16)
-		pix->sizeimage *= 2;
-}
-
 static int __tegra_channel_try_format(struct tegra_vi_channel *chan,
 				      struct v4l2_pix_format *pix)
 {
@@ -561,7 +531,7 @@ static int __tegra_channel_try_format(struct tegra_vi_channel *chan,
 		return ret;
 
 	v4l2_fill_pix_format(pix, &fmt.format);
-	tegra_channel_fmt_align(chan, pix, fmtinfo->bpp);
+	chan->vi->ops->vi_fmt_align(pix, fmtinfo->bpp);
 
 	__v4l2_subdev_state_free(sd_state);
 
@@ -613,7 +583,7 @@ static int tegra_channel_set_format(struct file *file, void *fh,
 		return ret;
 
 	v4l2_fill_pix_format(pix, &fmt.format);
-	tegra_channel_fmt_align(chan, pix, fmtinfo->bpp);
+	chan->vi->ops->vi_fmt_align(pix, fmtinfo->bpp);
 
 	chan->format = *pix;
 	chan->fmtinfo = fmtinfo;
@@ -649,7 +619,7 @@ static int tegra_channel_set_subdev_active_fmt(struct tegra_vi_channel *chan)
 	chan->format.bytesperline = chan->format.width * chan->fmtinfo->bpp;
 	chan->format.sizeimage = chan->format.bytesperline *
 				 chan->format.height;
-	tegra_channel_fmt_align(chan, &chan->format, chan->fmtinfo->bpp);
+	chan->vi->ops->vi_fmt_align(&chan->format, chan->fmtinfo->bpp);
 	tegra_channel_update_gangports(chan);
 
 	return 0;
@@ -818,7 +788,7 @@ static int tegra_channel_s_dv_timings(struct file *file, void *fh,
 	chan->format.height = bt->height;
 	chan->format.bytesperline = bt->width * chan->fmtinfo->bpp;
 	chan->format.sizeimage = chan->format.bytesperline * bt->height;
-	tegra_channel_fmt_align(chan, &chan->format, chan->fmtinfo->bpp);
+	chan->vi->ops->vi_fmt_align(&chan->format, chan->fmtinfo->bpp);
 	tegra_channel_update_gangports(chan);
 
 	return 0;
@@ -1149,7 +1119,7 @@ static int tegra_channel_init(struct tegra_vi_channel *chan)
 	chan->format.height = TEGRA_DEF_HEIGHT;
 	chan->format.bytesperline = TEGRA_DEF_WIDTH * chan->fmtinfo->bpp;
 	chan->format.sizeimage = chan->format.bytesperline * TEGRA_DEF_HEIGHT;
-	tegra_channel_fmt_align(chan, &chan->format, chan->fmtinfo->bpp);
+	vi->ops->vi_fmt_align(&chan->format, chan->fmtinfo->bpp);
 
 	ret = tegra_channel_host1x_syncpt_init(chan);
 	if (ret)
diff --git a/drivers/staging/media/tegra-video/vi.h b/drivers/staging/media/tegra-video/vi.h
index dfd834a69848..1021c730b595 100644
--- a/drivers/staging/media/tegra-video/vi.h
+++ b/drivers/staging/media/tegra-video/vi.h
@@ -25,17 +25,11 @@
 
 #define V4L2_CID_TEGRA_SYNCPT_TIMEOUT_RETRY	(V4L2_CTRL_CLASS_CAMERA | 0x1001)
 
-#define TEGRA_MIN_WIDTH		32U
-#define TEGRA_MAX_WIDTH		32768U
-#define TEGRA_MIN_HEIGHT	32U
-#define TEGRA_MAX_HEIGHT	32768U
-
 #define TEGRA_DEF_WIDTH		1920
 #define TEGRA_DEF_HEIGHT	1080
 #define TEGRA_IMAGE_FORMAT_DEF	32
 
 #define MAX_FORMAT_NUM		64
-#define SURFACE_ALIGN_BYTES	64
 
 enum tegra_vi_pg_mode {
 	TEGRA_VI_PG_DISABLED = 0,
@@ -45,6 +39,8 @@ enum tegra_vi_pg_mode {
 
 /**
  * struct tegra_vi_ops - Tegra VI operations
+ * @vi_fmt_align: modify `pix` to fit the hardware alignment
+ *		requirements and fill image geometry
  * @vi_start_streaming: starts media pipeline, subdevice streaming, sets up
  *		VI for capture and runs capture start and capture finish
  *		kthreads for capturing frames to buffer and returns them back.
@@ -52,6 +48,7 @@ enum tegra_vi_pg_mode {
  *		back any queued buffers.
  */
 struct tegra_vi_ops {
+	void (*vi_fmt_align)(struct v4l2_pix_format *pix, unsigned int bpp);
 	int (*vi_start_streaming)(struct vb2_queue *vq, u32 count);
 	void (*vi_stop_streaming)(struct vb2_queue *vq);
 };
-- 
2.34.1

[RESEND PATCH v4 14/21] staging: media: tegra-video: move default format to soc-specific data

[Luca Ceresoli]

The tegra_default_format in vi.c is specific to Tegra210 CSI.

In preparation for adding Tegra20 VIP support, move the default format to a
new field in the soc-specific `struct tegra_vi_soc`. Instead of an entire
format struct, only store a pointer to an item in the existing format
array.

No functional changes. The format pointed to is the same that used to be in
vi.c.

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>

---

Changed in v4:
 - Added review tags

No changes in v3
No changes in v2
---
 drivers/staging/media/tegra-video/tegra210.c |  2 ++
 drivers/staging/media/tegra-video/vi.c       | 11 +----------
 drivers/staging/media/tegra-video/vi.h       |  2 ++
 3 files changed, 5 insertions(+), 10 deletions(-)

diff --git a/drivers/staging/media/tegra-video/tegra210.c b/drivers/staging/media/tegra-video/tegra210.c
index 71483d0c19bf..28d3d05c12c4 100644
--- a/drivers/staging/media/tegra-video/tegra210.c
+++ b/drivers/staging/media/tegra-video/tegra210.c
@@ -771,8 +771,10 @@ const struct tegra_vi_soc tegra210_vi_soc = {
 	.hw_revision = 3,
 	.vi_max_channels = 6,
 #if IS_ENABLED(CONFIG_VIDEO_TEGRA_TPG)
+	.default_video_format = &tegra210_video_formats[0],
 	.vi_max_clk_hz = 499200000,
 #else
+	.default_video_format = &tegra210_video_formats[4],
 	.vi_max_clk_hz = 998400000,
 #endif
 };
diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index a76cad0e3026..3762fd273514 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -44,15 +44,6 @@ struct tegra_vi_graph_entity {
 	struct v4l2_subdev *subdev;
 };
 
-static const struct tegra_video_format tegra_default_format = {
-	.img_dt = TEGRA_IMAGE_DT_RAW10,
-	.bit_width = 10,
-	.code = MEDIA_BUS_FMT_SRGGB10_1X10,
-	.bpp = 2,
-	.img_fmt = TEGRA_IMAGE_FORMAT_DEF,
-	.fourcc = V4L2_PIX_FMT_SRGGB10,
-};
-
 static inline struct tegra_vi *
 host1x_client_to_vi(struct host1x_client *client)
 {
@@ -1111,7 +1102,7 @@ static int tegra_channel_init(struct tegra_vi_channel *chan)
 	init_waitqueue_head(&chan->done_wait);
 
 	/* initialize the video format */
-	chan->fmtinfo = &tegra_default_format;
+	chan->fmtinfo = chan->vi->soc->default_video_format;
 	chan->format.pixelformat = chan->fmtinfo->fourcc;
 	chan->format.colorspace = V4L2_COLORSPACE_SRGB;
 	chan->format.field = V4L2_FIELD_NONE;
diff --git a/drivers/staging/media/tegra-video/vi.h b/drivers/staging/media/tegra-video/vi.h
index 1021c730b595..879547073371 100644
--- a/drivers/staging/media/tegra-video/vi.h
+++ b/drivers/staging/media/tegra-video/vi.h
@@ -58,6 +58,7 @@ struct tegra_vi_ops {
  *
  * @video_formats: supported video formats
  * @nformats: total video formats
+ * @default_video_format: default video format (pointer to a @video_formats item)
  * @ops: vi operations
  * @hw_revision: VI hw_revision
  * @vi_max_channels: supported max streaming channels
@@ -66,6 +67,7 @@ struct tegra_vi_ops {
 struct tegra_vi_soc {
 	const struct tegra_video_format *video_formats;
 	const unsigned int nformats;
+	const struct tegra_video_format *default_video_format;
 	const struct tegra_vi_ops *ops;
 	u32 hw_revision;
 	unsigned int vi_max_channels;
-- 
2.34.1

[RESEND PATCH v4 15/21] staging: media: tegra-video: move MIPI calibration calls from VI to CSI

[Luca Ceresoli]

The CSI module does not handle all the MIPI lane calibration procedure,
leaving a small part of it to the VI module. In doing this,
tegra_channel_enable_stream() (vi.c) manipulates the private data of the
upstream subdev casting it to struct 'tegra_csi_channel', which will be
wrong after introducing a VIP (parallel video input) channel.

This prevents adding support for the VIP module.  It also breaks the
logical isolation between modules.

Since the lane calibration requirement does not exist in the parallel input
module, moving the calibration function to a per-module op is not
optimal. Instead move the calibration procedure in the CSI module, together
with the rest of the calibration procedures. After this change,
tegra_channel_enable_stream() just calls v4l2_subdev_call() to ask for a
stream start/stop to the CSI module, which in turn knows all the
CSI-specific details to implement it.

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>

---

Changed in v4:
 - Added review tags

No changes in v3
No changes in v2
---
 drivers/staging/media/tegra-video/csi.c | 44 ++++++++++++++++++++
 drivers/staging/media/tegra-video/vi.c  | 54 ++-----------------------
 2 files changed, 48 insertions(+), 50 deletions(-)

diff --git a/drivers/staging/media/tegra-video/csi.c b/drivers/staging/media/tegra-video/csi.c
index 9a03d5ccdf3c..b93fc879ef3a 100644
--- a/drivers/staging/media/tegra-video/csi.c
+++ b/drivers/staging/media/tegra-video/csi.c
@@ -328,12 +328,42 @@ static int tegra_csi_enable_stream(struct v4l2_subdev *subdev)
 	}
 
 	csi_chan->pg_mode = chan->pg_mode;
+
+	/*
+	 * Tegra CSI receiver can detect the first LP to HS transition.
+	 * So, start the CSI stream-on prior to sensor stream-on and
+	 * vice-versa for stream-off.
+	 */
 	ret = csi->ops->csi_start_streaming(csi_chan);
 	if (ret < 0)
 		goto finish_calibration;
 
+	if (csi_chan->mipi) {
+		struct v4l2_subdev *src_subdev;
+		/*
+		 * TRM has incorrectly documented to wait for done status from
+		 * calibration logic after CSI interface power on.
+		 * As per the design, calibration results are latched and applied
+		 * to the pads only when the link is in LP11 state which will happen
+		 * during the sensor stream-on.
+		 * CSI subdev stream-on triggers start of MIPI pads calibration.
+		 * Wait for calibration to finish here after sensor subdev stream-on.
+		 */
+		src_subdev = tegra_channel_get_remote_source_subdev(chan);
+		ret = v4l2_subdev_call(src_subdev, video, s_stream, true);
+		err = tegra_mipi_finish_calibration(csi_chan->mipi);
+
+		if (ret < 0 && ret != -ENOIOCTLCMD)
+			goto disable_csi_stream;
+
+		if (err < 0)
+			dev_warn(csi->dev, "MIPI calibration failed: %d\n", err);
+	}
+
 	return 0;
 
+disable_csi_stream:
+	csi->ops->csi_stop_streaming(csi_chan);
 finish_calibration:
 	if (csi_chan->mipi)
 		tegra_mipi_finish_calibration(csi_chan->mipi);
@@ -352,10 +382,24 @@ static int tegra_csi_enable_stream(struct v4l2_subdev *subdev)
 
 static int tegra_csi_disable_stream(struct v4l2_subdev *subdev)
 {
+	struct tegra_vi_channel *chan = v4l2_get_subdev_hostdata(subdev);
 	struct tegra_csi_channel *csi_chan = to_csi_chan(subdev);
 	struct tegra_csi *csi = csi_chan->csi;
 	int err;
 
+	/*
+	 * Stream-off subdevices in reverse order to stream-on.
+	 * Remote source subdev in TPG mode is same as CSI subdev.
+	 */
+	if (csi_chan->mipi) {
+		struct v4l2_subdev *src_subdev;
+
+		src_subdev = tegra_channel_get_remote_source_subdev(chan);
+		err = v4l2_subdev_call(src_subdev, video, s_stream, false);
+		if (err < 0 && err != -ENOIOCTLCMD)
+			dev_err_probe(csi->dev, err, "source subdev stream off failed\n");
+	}
+
 	csi->ops->csi_stop_streaming(csi_chan);
 
 	if (csi_chan->mipi) {
diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index 3762fd273514..a26eb1ca869f 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -187,49 +187,15 @@ tegra_channel_get_remote_source_subdev(struct tegra_vi_channel *chan)
 
 static int tegra_channel_enable_stream(struct tegra_vi_channel *chan)
 {
-	struct v4l2_subdev *csi_subdev, *src_subdev;
-	struct tegra_csi_channel *csi_chan;
-	int ret, err;
+	struct v4l2_subdev *subdev;
+	int ret;
 
-	/*
-	 * Tegra CSI receiver can detect the first LP to HS transition.
-	 * So, start the CSI stream-on prior to sensor stream-on and
-	 * vice-versa for stream-off.
-	 */
-	csi_subdev = tegra_channel_get_remote_csi_subdev(chan);
-	ret = v4l2_subdev_call(csi_subdev, video, s_stream, true);
+	subdev = tegra_channel_get_remote_csi_subdev(chan);
+	ret = v4l2_subdev_call(subdev, video, s_stream, true);
 	if (ret < 0 && ret != -ENOIOCTLCMD)
 		return ret;
 
-	if (IS_ENABLED(CONFIG_VIDEO_TEGRA_TPG))
-		return 0;
-
-	csi_chan = v4l2_get_subdevdata(csi_subdev);
-	/*
-	 * TRM has incorrectly documented to wait for done status from
-	 * calibration logic after CSI interface power on.
-	 * As per the design, calibration results are latched and applied
-	 * to the pads only when the link is in LP11 state which will happen
-	 * during the sensor stream-on.
-	 * CSI subdev stream-on triggers start of MIPI pads calibration.
-	 * Wait for calibration to finish here after sensor subdev stream-on.
-	 */
-	src_subdev = tegra_channel_get_remote_source_subdev(chan);
-	ret = v4l2_subdev_call(src_subdev, video, s_stream, true);
-	err = tegra_mipi_finish_calibration(csi_chan->mipi);
-
-	if (ret < 0 && ret != -ENOIOCTLCMD)
-		goto err_disable_csi_stream;
-
-	if (err < 0)
-		dev_warn(csi_chan->csi->dev,
-			 "MIPI calibration failed: %d\n", err);
-
 	return 0;
-
-err_disable_csi_stream:
-	v4l2_subdev_call(csi_subdev, video, s_stream, false);
-	return ret;
 }
 
 static int tegra_channel_disable_stream(struct tegra_vi_channel *chan)
@@ -237,18 +203,6 @@ static int tegra_channel_disable_stream(struct tegra_vi_channel *chan)
 	struct v4l2_subdev *subdev;
 	int ret;
 
-	/*
-	 * Stream-off subdevices in reverse order to stream-on.
-	 * Remote source subdev in TPG mode is same as CSI subdev.
-	 */
-	subdev = tegra_channel_get_remote_source_subdev(chan);
-	ret = v4l2_subdev_call(subdev, video, s_stream, false);
-	if (ret < 0 && ret != -ENOIOCTLCMD)
-		return ret;
-
-	if (IS_ENABLED(CONFIG_VIDEO_TEGRA_TPG))
-		return 0;
-
 	subdev = tegra_channel_get_remote_csi_subdev(chan);
 	ret = v4l2_subdev_call(subdev, video, s_stream, false);
 	if (ret < 0 && ret != -ENOIOCTLCMD)
-- 
2.34.1

[RESEND PATCH v4 16/21] staging: media: tegra-video: add a per-soc enable/disable op

[Luca Ceresoli]

The Tegra20 VI needs an additional operation to enable the VI, add an
operation for that.

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>

---

Changed in v4:
 - Added review tags

No changes in v3
No changes in v2
---
 drivers/staging/media/tegra-video/vi.c | 7 +++++++
 drivers/staging/media/tegra-video/vi.h | 4 ++++
 2 files changed, 11 insertions(+)

diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index a26eb1ca869f..22f6d6478d3e 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -1853,6 +1853,9 @@ static int tegra_vi_probe(struct platform_device *pdev)
 	vi->client.ops = &vi_client_ops;
 	vi->client.dev = &pdev->dev;
 
+	if (vi->ops->vi_enable)
+		vi->ops->vi_enable(vi, true);
+
 	ret = host1x_client_register(&vi->client);
 	if (ret < 0) {
 		dev_err(&pdev->dev,
@@ -1863,6 +1866,8 @@ static int tegra_vi_probe(struct platform_device *pdev)
 	return 0;
 
 rpm_disable:
+	if (vi->ops->vi_enable)
+		vi->ops->vi_enable(vi, false);
 	pm_runtime_disable(&pdev->dev);
 	return ret;
 }
@@ -1879,6 +1884,8 @@ static int tegra_vi_remove(struct platform_device *pdev)
 		return err;
 	}
 
+	if (vi->ops->vi_enable)
+		vi->ops->vi_enable(vi, false);
 	pm_runtime_disable(&pdev->dev);
 
 	return 0;
diff --git a/drivers/staging/media/tegra-video/vi.h b/drivers/staging/media/tegra-video/vi.h
index 879547073371..851c4f3fcb91 100644
--- a/drivers/staging/media/tegra-video/vi.h
+++ b/drivers/staging/media/tegra-video/vi.h
@@ -37,8 +37,11 @@ enum tegra_vi_pg_mode {
 	TEGRA_VI_PG_PATCH,
 };
 
+struct tegra_vi;
+
 /**
  * struct tegra_vi_ops - Tegra VI operations
+ * @vi_enable: soc-specific operations needed to enable/disable the VI peripheral
  * @vi_fmt_align: modify `pix` to fit the hardware alignment
  *		requirements and fill image geometry
  * @vi_start_streaming: starts media pipeline, subdevice streaming, sets up
@@ -48,6 +51,7 @@ enum tegra_vi_pg_mode {
  *		back any queued buffers.
  */
 struct tegra_vi_ops {
+	int (*vi_enable)(struct tegra_vi *vi, bool on);
 	void (*vi_fmt_align)(struct v4l2_pix_format *pix, unsigned int bpp);
 	int (*vi_start_streaming)(struct vb2_queue *vq, u32 count);
 	void (*vi_stop_streaming)(struct vb2_queue *vq);
-- 
2.34.1

[RESEND PATCH v4 17/21] staging: media: tegra-video: move syncpt init/free to a per-soc op

[Luca Ceresoli]

tegra_channel_host1x_syncpt_init() gets the host1x syncpts needed for the
Tegra210 implementation, and tegra_channel_host1x_syncpts_free() puts
them.

Tegra20 needs to get and put a different syncpt. In preparation for adding
Tegra20 support, move these functions to new ops in the soc-specific
`struct tegra_vi_ops` .

No functional changes.

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>

---

Changed in v4:
 - Added review tags

No changes in v3
No changes in v2
---
 drivers/staging/media/tegra-video/tegra210.c | 52 ++++++++++++++++++++
 drivers/staging/media/tegra-video/vi.c       | 52 ++------------------
 drivers/staging/media/tegra-video/vi.h       |  5 ++
 3 files changed, 60 insertions(+), 49 deletions(-)

diff --git a/drivers/staging/media/tegra-video/tegra210.c b/drivers/staging/media/tegra-video/tegra210.c
index 28d3d05c12c4..d47ba79bac75 100644
--- a/drivers/staging/media/tegra-video/tegra210.c
+++ b/drivers/staging/media/tegra-video/tegra210.c
@@ -179,6 +179,56 @@ static u32 vi_csi_read(struct tegra_vi_channel *chan, u8 portno,
 /*
  * Tegra210 VI channel capture operations
  */
+
+static int tegra210_channel_host1x_syncpt_init(struct tegra_vi_channel *chan)
+{
+	struct tegra_vi *vi = chan->vi;
+	unsigned long flags = HOST1X_SYNCPT_CLIENT_MANAGED;
+	struct host1x_syncpt *fs_sp;
+	struct host1x_syncpt *mw_sp;
+	int ret, i;
+
+	for (i = 0; i < chan->numgangports; i++) {
+		fs_sp = host1x_syncpt_request(&vi->client, flags);
+		if (!fs_sp) {
+			dev_err(vi->dev, "failed to request frame start syncpoint\n");
+			ret = -ENOMEM;
+			goto free_syncpts;
+		}
+
+		mw_sp = host1x_syncpt_request(&vi->client, flags);
+		if (!mw_sp) {
+			dev_err(vi->dev, "failed to request memory ack syncpoint\n");
+			host1x_syncpt_put(fs_sp);
+			ret = -ENOMEM;
+			goto free_syncpts;
+		}
+
+		chan->frame_start_sp[i] = fs_sp;
+		chan->mw_ack_sp[i] = mw_sp;
+		spin_lock_init(&chan->sp_incr_lock[i]);
+	}
+
+	return 0;
+
+free_syncpts:
+	for (i = 0; i < chan->numgangports; i++) {
+		host1x_syncpt_put(chan->mw_ack_sp[i]);
+		host1x_syncpt_put(chan->frame_start_sp[i]);
+	}
+	return ret;
+}
+
+static void tegra210_channel_host1x_syncpt_free(struct tegra_vi_channel *chan)
+{
+	int i;
+
+	for (i = 0; i < chan->numgangports; i++) {
+		host1x_syncpt_put(chan->mw_ack_sp[i]);
+		host1x_syncpt_put(chan->frame_start_sp[i]);
+	}
+}
+
 static void tegra210_fmt_align(struct v4l2_pix_format *pix, unsigned int bpp)
 {
 	unsigned int min_bpl;
@@ -758,6 +808,8 @@ static const struct tegra_video_format tegra210_video_formats[] = {
 
 /* Tegra210 VI operations */
 static const struct tegra_vi_ops tegra210_vi_ops = {
+	.channel_host1x_syncpt_init = tegra210_channel_host1x_syncpt_init,
+	.channel_host1x_syncpt_free = tegra210_channel_host1x_syncpt_free,
 	.vi_fmt_align = tegra210_fmt_align,
 	.vi_start_streaming = tegra210_vi_start_streaming,
 	.vi_stop_streaming = tegra210_vi_stop_streaming,
diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index 22f6d6478d3e..760606c65a97 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -973,21 +973,11 @@ static int tegra_channel_setup_ctrl_handler(struct tegra_vi_channel *chan)
 	return 0;
 }
 
-static void tegra_channel_host1x_syncpts_free(struct tegra_vi_channel *chan)
-{
-	int i;
-
-	for (i = 0; i < chan->numgangports; i++) {
-		host1x_syncpt_put(chan->mw_ack_sp[i]);
-		host1x_syncpt_put(chan->frame_start_sp[i]);
-	}
-}
-
 static void tegra_channel_cleanup(struct tegra_vi_channel *chan)
 {
 	v4l2_ctrl_handler_free(&chan->ctrl_handler);
 	media_entity_cleanup(&chan->video.entity);
-	tegra_channel_host1x_syncpts_free(chan);
+	chan->vi->ops->channel_host1x_syncpt_free(chan);
 	mutex_destroy(&chan->video_lock);
 }
 
@@ -1005,42 +995,6 @@ void tegra_channels_cleanup(struct tegra_vi *vi)
 	}
 }
 
-static int tegra_channel_host1x_syncpt_init(struct tegra_vi_channel *chan)
-{
-	struct tegra_vi *vi = chan->vi;
-	unsigned long flags = HOST1X_SYNCPT_CLIENT_MANAGED;
-	struct host1x_syncpt *fs_sp;
-	struct host1x_syncpt *mw_sp;
-	int ret, i;
-
-	for (i = 0; i < chan->numgangports; i++) {
-		fs_sp = host1x_syncpt_request(&vi->client, flags);
-		if (!fs_sp) {
-			dev_err(vi->dev, "failed to request frame start syncpoint\n");
-			ret = -ENOMEM;
-			goto free_syncpts;
-		}
-
-		mw_sp = host1x_syncpt_request(&vi->client, flags);
-		if (!mw_sp) {
-			dev_err(vi->dev, "failed to request memory ack syncpoint\n");
-			host1x_syncpt_put(fs_sp);
-			ret = -ENOMEM;
-			goto free_syncpts;
-		}
-
-		chan->frame_start_sp[i] = fs_sp;
-		chan->mw_ack_sp[i] = mw_sp;
-		spin_lock_init(&chan->sp_incr_lock[i]);
-	}
-
-	return 0;
-
-free_syncpts:
-	tegra_channel_host1x_syncpts_free(chan);
-	return ret;
-}
-
 static int tegra_channel_init(struct tegra_vi_channel *chan)
 {
 	struct tegra_vi *vi = chan->vi;
@@ -1066,7 +1020,7 @@ static int tegra_channel_init(struct tegra_vi_channel *chan)
 	chan->format.sizeimage = chan->format.bytesperline * TEGRA_DEF_HEIGHT;
 	vi->ops->vi_fmt_align(&chan->format, chan->fmtinfo->bpp);
 
-	ret = tegra_channel_host1x_syncpt_init(chan);
+	ret = vi->ops->channel_host1x_syncpt_init(chan);
 	if (ret)
 		return ret;
 
@@ -1129,7 +1083,7 @@ static int tegra_channel_init(struct tegra_vi_channel *chan)
 cleanup_media:
 	media_entity_cleanup(&chan->video.entity);
 free_syncpts:
-	tegra_channel_host1x_syncpts_free(chan);
+	vi->ops->channel_host1x_syncpt_free(chan);
 	return ret;
 }
 
diff --git a/drivers/staging/media/tegra-video/vi.h b/drivers/staging/media/tegra-video/vi.h
index 851c4f3fcb91..8fadca33bcc9 100644
--- a/drivers/staging/media/tegra-video/vi.h
+++ b/drivers/staging/media/tegra-video/vi.h
@@ -38,10 +38,13 @@ enum tegra_vi_pg_mode {
 };
 
 struct tegra_vi;
+struct tegra_vi_channel;
 
 /**
  * struct tegra_vi_ops - Tegra VI operations
  * @vi_enable: soc-specific operations needed to enable/disable the VI peripheral
+ * @channel_host1x_syncpt_init: initialize synchronization points
+ * @channel_host1x_syncpt_free: free all synchronization points
  * @vi_fmt_align: modify `pix` to fit the hardware alignment
  *		requirements and fill image geometry
  * @vi_start_streaming: starts media pipeline, subdevice streaming, sets up
@@ -52,6 +55,8 @@ struct tegra_vi;
  */
 struct tegra_vi_ops {
 	int (*vi_enable)(struct tegra_vi *vi, bool on);
+	int (*channel_host1x_syncpt_init)(struct tegra_vi_channel *chan);
+	void (*channel_host1x_syncpt_free)(struct tegra_vi_channel *chan);
 	void (*vi_fmt_align)(struct v4l2_pix_format *pix, unsigned int bpp);
 	int (*vi_start_streaming)(struct vb2_queue *vq, u32 count);
 	void (*vi_stop_streaming)(struct vb2_queue *vq);
-- 
2.34.1

[RESEND PATCH v4 18/21] staging: media: tegra-video: add syncpts for Tegra20 to struct tegra_vi

[Luca Ceresoli]

In preparation to implement Tegra20 parallel video capture, add a variable
to hold the required syncpt and document all the syncpt variables.

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>

---

Changed in v4:
 - Added review tags

Changed in v3:
 - recycle mw_ack_sp[0] instead of adding out_sp

No changes in v2
---
 drivers/staging/media/tegra-video/vi.h | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/media/tegra-video/vi.h b/drivers/staging/media/tegra-video/vi.h
index 8fadca33bcc9..d5e1ed4217e0 100644
--- a/drivers/staging/media/tegra-video/vi.h
+++ b/drivers/staging/media/tegra-video/vi.h
@@ -117,11 +117,13 @@ struct tegra_vi {
  * @vi: Tegra video input device structure
  * @frame_start_sp: host1x syncpoint pointer to synchronize programmed capture
  *		start condition with hardware frame start events through host1x
- *		syncpoint counters.
+ *		syncpoint counters. (Tegra210)
  * @mw_ack_sp: host1x syncpoint pointer to synchronize programmed memory write
  *		ack trigger condition with hardware memory write done at end of
- *		frame through host1x syncpoint counters.
+ *		frame through host1x syncpoint counters (On Tegra20 used for the
+ *              OUT_1 syncpt)
  * @sp_incr_lock: protects cpu syncpoint increment.
+ * @next_out_sp_idx: next expected value for mw_ack_sp[0], i.e. OUT_1 (Tegra20)
  *
  * @kthread_start_capture: kthread to start capture of single frame when
  *		vb buffer is available. This thread programs VI CSI hardware
@@ -173,6 +175,7 @@ struct tegra_vi_channel {
 	struct host1x_syncpt *mw_ack_sp[GANG_PORTS_MAX];
 	/* protects the cpu syncpoint increment */
 	spinlock_t sp_incr_lock[GANG_PORTS_MAX];
+	u32 next_out_sp_idx;
 
 	struct task_struct *kthread_start_capture;
 	wait_queue_head_t start_wait;
-- 
2.34.1

[RESEND PATCH v4 19/21] staging: media: tegra-video: add hooks for planar YUV and H/V flip

[Luca Ceresoli]

Tegra20 supports planar YUV422 capture, which can be implemented by writing
U and V base address registers in addition to the "main" base buffer
address register.

It also supports H and V flip, which among others requires to write the
start address (i.e. the 1st offset to write, at the end of the buffer or
line) in more registers for Y and, for planar formats, U and V.

Add minimal hooks in VI to allow per-SoC optional support to those
features:

 - variables in struct tegra_vi for the U and V buffer base offsets
 - variables in struct tegra_vi for the Y, U and V buffer start offsets
 - an optional per-soc VI operation to compute those values on queue setup

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>

---

Changed in v4:
 - Added review tags

No changes in v3
No changes in v2
---
 drivers/staging/media/tegra-video/vi.c |  4 ++++
 drivers/staging/media/tegra-video/vi.h | 14 ++++++++++++++
 2 files changed, 18 insertions(+)

diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index 760606c65a97..4a066b61ab8e 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -92,6 +92,7 @@ tegra_get_format_by_fourcc(struct tegra_vi *vi, u32 fourcc)
 /*
  * videobuf2 queue operations
  */
+
 static int tegra_channel_queue_setup(struct vb2_queue *vq,
 				     unsigned int *nbuffers,
 				     unsigned int *nplanes,
@@ -107,6 +108,9 @@ static int tegra_channel_queue_setup(struct vb2_queue *vq,
 	sizes[0] = chan->format.sizeimage;
 	alloc_devs[0] = chan->vi->dev;
 
+	if (chan->vi->ops->channel_queue_setup)
+		chan->vi->ops->channel_queue_setup(chan);
+
 	return 0;
 }
 
diff --git a/drivers/staging/media/tegra-video/vi.h b/drivers/staging/media/tegra-video/vi.h
index d5e1ed4217e0..0503eb678556 100644
--- a/drivers/staging/media/tegra-video/vi.h
+++ b/drivers/staging/media/tegra-video/vi.h
@@ -47,6 +47,7 @@ struct tegra_vi_channel;
  * @channel_host1x_syncpt_free: free all synchronization points
  * @vi_fmt_align: modify `pix` to fit the hardware alignment
  *		requirements and fill image geometry
+ * @channel_queue_setup: additional operations at the end of vb2_ops::queue_setup
  * @vi_start_streaming: starts media pipeline, subdevice streaming, sets up
  *		VI for capture and runs capture start and capture finish
  *		kthreads for capturing frames to buffer and returns them back.
@@ -58,6 +59,7 @@ struct tegra_vi_ops {
 	int (*channel_host1x_syncpt_init)(struct tegra_vi_channel *chan);
 	void (*channel_host1x_syncpt_free)(struct tegra_vi_channel *chan);
 	void (*vi_fmt_align)(struct v4l2_pix_format *pix, unsigned int bpp);
+	void (*channel_queue_setup)(struct tegra_vi_channel *chan);
 	int (*vi_start_streaming)(struct vb2_queue *vq, u32 count);
 	void (*vi_stop_streaming)(struct vb2_queue *vq);
 };
@@ -148,6 +150,12 @@ struct tegra_vi {
  * @queue: vb2 buffers queue
  * @sequence: V4L2 buffers sequence number
  *
+ * @addr_offset_u: U plane base address, relative to buffer base address (only for planar)
+ * @addr_offset_v: V plane base address, relative to buffer base address (only for planar)
+ * @start_offset:   1st Y byte to write, relative to buffer base address (for H/V flip)
+ * @start_offset_u: 1st U byte to write, relative to buffer base address (for H/V flip)
+ * @start_offset_v: 1st V byte to write, relative to buffer base address (for H/V flip)
+ *
  * @capture: list of queued buffers for capture
  * @start_lock: protects the capture queued list
  * @done: list of capture done queued buffers
@@ -187,6 +195,12 @@ struct tegra_vi_channel {
 	struct vb2_queue queue;
 	u32 sequence;
 
+	unsigned int addr_offset_u;
+	unsigned int addr_offset_v;
+	unsigned int start_offset;
+	unsigned int start_offset_u;
+	unsigned int start_offset_v;
+
 	struct list_head capture;
 	/* protects the capture queued list */
 	spinlock_t start_lock;
-- 
2.34.1

[RESEND PATCH v4 20/21] staging: media: tegra-video: add H/V flip controls

[Luca Ceresoli]

Tegra20 can do horizontal and vertical image flip, but Tegra210 cannot
(either the hardware, or this driver).

In preparation to adding Tegra20 support, add a flag in struct tegra_vi_soc
so the generic vi.c code knows whether the flip controls should be added or
not.

Also provide a generic implementation that simply sets two flags in the
channel struct. The Tegra20 implementation will enable flipping at stream
start based on those flags.

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>

---

Changed in v4:
 - Added review tags

No changes in v3
No changes in v2
---
 drivers/staging/media/tegra-video/vi.c | 14 +++++++++++++-
 drivers/staging/media/tegra-video/vi.h |  8 ++++++++
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index 4a066b61ab8e..d1c6877163c2 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -29,7 +29,7 @@
 #include "vi.h"
 #include "video.h"
 
-#define MAX_CID_CONTROLS		1
+#define MAX_CID_CONTROLS		3
 
 /**
  * struct tegra_vi_graph_entity - Entity in the video graph
@@ -893,6 +893,12 @@ static int vi_s_ctrl(struct v4l2_ctrl *ctrl)
 	case V4L2_CID_TEGRA_SYNCPT_TIMEOUT_RETRY:
 		chan->syncpt_timeout_retry = ctrl->val;
 		break;
+	case V4L2_CID_HFLIP:
+		chan->hflip = ctrl->val;
+		break;
+	case V4L2_CID_VFLIP:
+		chan->vflip = ctrl->val;
+		break;
 	default:
 		return -EINVAL;
 	}
@@ -964,6 +970,12 @@ static int tegra_channel_setup_ctrl_handler(struct tegra_vi_channel *chan)
 		v4l2_ctrl_handler_free(&chan->ctrl_handler);
 		return ret;
 	}
+
+	if (chan->vi->soc->has_h_v_flip) {
+		v4l2_ctrl_new_std(&chan->ctrl_handler, &vi_ctrl_ops, V4L2_CID_HFLIP, 0, 1, 1, 0);
+		v4l2_ctrl_new_std(&chan->ctrl_handler, &vi_ctrl_ops, V4L2_CID_VFLIP, 0, 1, 1, 0);
+	}
+
 #endif
 
 	/* setup the controls */
diff --git a/drivers/staging/media/tegra-video/vi.h b/drivers/staging/media/tegra-video/vi.h
index 0503eb678556..8fa817757059 100644
--- a/drivers/staging/media/tegra-video/vi.h
+++ b/drivers/staging/media/tegra-video/vi.h
@@ -74,6 +74,7 @@ struct tegra_vi_ops {
  * @hw_revision: VI hw_revision
  * @vi_max_channels: supported max streaming channels
  * @vi_max_clk_hz: VI clock max frequency
+ * @has_h_v_flip: the chip can do H adn V flip, and the driver implements it
  */
 struct tegra_vi_soc {
 	const struct tegra_video_format *video_formats;
@@ -83,6 +84,7 @@ struct tegra_vi_soc {
 	u32 hw_revision;
 	unsigned int vi_max_channels;
 	unsigned int vi_max_clk_hz;
+	bool has_h_v_flip:1;
 };
 
 /**
@@ -170,6 +172,9 @@ struct tegra_vi {
  * @syncpt_timeout_retry: syncpt timeout retry count for the capture
  * @pg_mode: test pattern generator mode (disabled/direct/patch)
  * @notifier: V4L2 asynchronous subdevs notifier
+ *
+ * @hflip: Horizontal flip is enabled
+ * @vflip: Vertical flip is enabled
  */
 struct tegra_vi_channel {
 	struct list_head list;
@@ -218,6 +223,9 @@ struct tegra_vi_channel {
 	enum tegra_vi_pg_mode pg_mode;
 
 	struct v4l2_async_notifier notifier;
+
+	bool hflip:1;
+	bool vflip:1;
 };
 
 /**
-- 
2.34.1

[RESEND PATCH v4 21/21] staging: media: tegra-video: add support for Tegra20 parallel input

[Luca Ceresoli]

The VI peripheral of Tegra supports capturing from MIPI CSI-2 or parallel
video (called VIP in the docs).

The staging tegra-video driver currently implements MIPI CSI-2 video
capture for Tegra210. Add support for parallel video capture (VIP) on
Tegra20. With the generalizations added to the VI driver in previous
commits, this is only a matter of adding the vip.c and tegra20.c
implementations and registering them.

Unfortunately there was no documentation available for the VI or VIP
peripherals of Tegra20 (or any other Tegra chips). This implementation has
been based entirely on the code from a vendor kernel based on Linux 3.1 and
massively adapted to fit into the tegra-video driver. Parts of this code is
definitely non-optimal to say the least (especially tegra20_vi_enable() and
the single-frame capture logic), but it was impossible to improve it.

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>

---

Changed in v4:
 - Added review tags

Changed in v3 (suggested by Dmitry Osipenko):
 - merged the VIP patch and the Tegra20 patch to avoid chicken-egg problem
   due to the two modules depending on each other at build time
 - move tegra20_vip_soc to vip.c
 - remove channel@0 node from device tree parsing
 - remove unused variable

Changed in v2:
 - fix tegra20_vi_enable() to clear bit when on==false
 - clamp width/height from set/try_fmt to avoid returning sizeimage=0
   (fixes v4l2-compliance)
---
 drivers/staging/media/tegra-video/Makefile  |   2 +
 drivers/staging/media/tegra-video/tegra20.c | 661 ++++++++++++++++++++
 drivers/staging/media/tegra-video/vi.c      |   3 +
 drivers/staging/media/tegra-video/vi.h      |   3 +
 drivers/staging/media/tegra-video/video.c   |   5 +
 drivers/staging/media/tegra-video/video.h   |   1 +
 drivers/staging/media/tegra-video/vip.c     | 290 +++++++++
 drivers/staging/media/tegra-video/vip.h     |  68 ++
 8 files changed, 1033 insertions(+)
 create mode 100644 drivers/staging/media/tegra-video/tegra20.c
 create mode 100644 drivers/staging/media/tegra-video/vip.c
 create mode 100644 drivers/staging/media/tegra-video/vip.h

diff --git a/drivers/staging/media/tegra-video/Makefile b/drivers/staging/media/tegra-video/Makefile
index dfa2ef8f99ef..6c7552e05109 100644
--- a/drivers/staging/media/tegra-video/Makefile
+++ b/drivers/staging/media/tegra-video/Makefile
@@ -2,7 +2,9 @@
 tegra-video-objs := \
 		video.o \
 		vi.o \
+		vip.o \
 		csi.o
 
+tegra-video-$(CONFIG_ARCH_TEGRA_2x_SOC)  += tegra20.o
 tegra-video-$(CONFIG_ARCH_TEGRA_210_SOC) += tegra210.o
 obj-$(CONFIG_VIDEO_TEGRA) += tegra-video.o
diff --git a/drivers/staging/media/tegra-video/tegra20.c b/drivers/staging/media/tegra-video/tegra20.c
new file mode 100644
index 000000000000..ac048bbd58f0
--- /dev/null
+++ b/drivers/staging/media/tegra-video/tegra20.c
@@ -0,0 +1,661 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Tegra20-specific VI implementation
+ *
+ * Copyright (C) 2022 SKIDATA GmbH
+ * Author: Luca Ceresoli <luca.ceresoli@bootlin.com>
+ */
+
+/*
+ * This source file contains Tegra20 supported video formats,
+ * VI and VIP SoC specific data, operations and registers accessors.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/delay.h>
+#include <linux/host1x.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/v4l2-mediabus.h>
+
+#include "vip.h"
+#include "vi.h"
+
+#define TEGRA_VI_SYNCPT_WAIT_TIMEOUT			msecs_to_jiffies(200)
+
+/* This are just good-sense numbers. The actual min/max is not documented. */
+#define TEGRA20_MIN_WIDTH	32U
+#define TEGRA20_MIN_HEIGHT	32U
+#define TEGRA20_MAX_WIDTH	2048U
+#define TEGRA20_MAX_HEIGHT	2048U
+
+/* --------------------------------------------------------------------------
+ * Registers
+ */
+
+#define TEGRA_VI_CONT_SYNCPT_OUT_1			0x0060
+#define       VI_CONT_SYNCPT_OUT_1_CONTINUOUS_SYNCPT	BIT(8)
+#define       VI_CONT_SYNCPT_OUT_1_SYNCPT_IDX_SFT	0
+
+#define TEGRA_VI_VI_INPUT_CONTROL			0x0088
+#define       VI_INPUT_FIELD_DETECT			BIT(27)
+#define       VI_INPUT_BT656				BIT(25)
+#define       VI_INPUT_YUV_INPUT_FORMAT_SFT		8  /* bits [9:8] */
+#define       VI_INPUT_YUV_INPUT_FORMAT_UYVY		(0 << VI_INPUT_YUV_INPUT_FORMAT_SFT)
+#define       VI_INPUT_YUV_INPUT_FORMAT_VYUY		(1 << VI_INPUT_YUV_INPUT_FORMAT_SFT)
+#define       VI_INPUT_YUV_INPUT_FORMAT_YUYV		(2 << VI_INPUT_YUV_INPUT_FORMAT_SFT)
+#define       VI_INPUT_YUV_INPUT_FORMAT_YVYU		(3 << VI_INPUT_YUV_INPUT_FORMAT_SFT)
+#define       VI_INPUT_INPUT_FORMAT_SFT			2  /* bits [5:2] */
+#define       VI_INPUT_INPUT_FORMAT_YUV422		(0 << VI_INPUT_INPUT_FORMAT_SFT)
+#define       VI_INPUT_VIP_INPUT_ENABLE			BIT(1)
+
+#define TEGRA_VI_VI_CORE_CONTROL			0x008c
+#define       VI_VI_CORE_CONTROL_PLANAR_CONV_IN_SEL_EXT	BIT(31)
+#define       VI_VI_CORE_CONTROL_CSC_INPUT_SEL_EXT	BIT(30)
+#define       VI_VI_CORE_CONTROL_INPUT_TO_ALT_MUX_SFT	27
+#define       VI_VI_CORE_CONTROL_INPUT_TO_CORE_EXT_SFT	24
+#define       VI_VI_CORE_CONTROL_OUTPUT_TO_ISP_EXT_SFT	21
+#define       VI_VI_CORE_CONTROL_ISP_HOST_STALL_OFF	BIT(20)
+#define       VI_VI_CORE_CONTROL_V_DOWNSCALING		BIT(19)
+#define       VI_VI_CORE_CONTROL_V_AVERAGING		BIT(18)
+#define       VI_VI_CORE_CONTROL_H_DOWNSCALING		BIT(17)
+#define       VI_VI_CORE_CONTROL_H_AVERAGING		BIT(16)
+#define       VI_VI_CORE_CONTROL_CSC_INPUT_SEL		BIT(11)
+#define       VI_VI_CORE_CONTROL_PLANAR_CONV_INPUT_SEL	BIT(10)
+#define       VI_VI_CORE_CONTROL_INPUT_TO_CORE_SFT	8
+#define       VI_VI_CORE_CONTROL_ISP_DOWNSAMPLE_SFT	5
+#define       VI_VI_CORE_CONTROL_OUTPUT_TO_EPP_SFT	2
+#define       VI_VI_CORE_CONTROL_OUTPUT_TO_ISP_SFT	0
+
+#define TEGRA_VI_VI_FIRST_OUTPUT_CONTROL		0x0090
+#define       VI_OUTPUT_FORMAT_EXT			BIT(22)
+#define       VI_OUTPUT_V_DIRECTION			BIT(20)
+#define       VI_OUTPUT_H_DIRECTION			BIT(19)
+#define       VI_OUTPUT_YUV_OUTPUT_FORMAT_SFT		17
+#define       VI_OUTPUT_YUV_OUTPUT_FORMAT_UYVY		(0 << VI_OUTPUT_YUV_OUTPUT_FORMAT_SFT)
+#define       VI_OUTPUT_YUV_OUTPUT_FORMAT_VYUY		(1 << VI_OUTPUT_YUV_OUTPUT_FORMAT_SFT)
+#define       VI_OUTPUT_YUV_OUTPUT_FORMAT_YUYV		(2 << VI_OUTPUT_YUV_OUTPUT_FORMAT_SFT)
+#define       VI_OUTPUT_YUV_OUTPUT_FORMAT_YVYU		(3 << VI_OUTPUT_YUV_OUTPUT_FORMAT_SFT)
+#define       VI_OUTPUT_OUTPUT_BYTE_SWAP		BIT(16)
+#define       VI_OUTPUT_LAST_PIXEL_DUPLICATION		BIT(8)
+#define       VI_OUTPUT_OUTPUT_FORMAT_SFT		0
+#define       VI_OUTPUT_OUTPUT_FORMAT_YUV422POST	(3 << VI_OUTPUT_OUTPUT_FORMAT_SFT)
+#define       VI_OUTPUT_OUTPUT_FORMAT_YUV420PLANAR	(6 << VI_OUTPUT_OUTPUT_FORMAT_SFT)
+
+#define TEGRA_VI_VIP_H_ACTIVE				0x00a4
+#define       VI_VIP_H_ACTIVE_PERIOD_SFT		16 /* active pixels/line, must be even */
+#define       VI_VIP_H_ACTIVE_START_SFT			0
+
+#define TEGRA_VI_VIP_V_ACTIVE				0x00a8
+#define       VI_VIP_V_ACTIVE_PERIOD_SFT		16 /* active lines */
+#define       VI_VIP_V_ACTIVE_START_SFT			0
+
+#define TEGRA_VI_VB0_START_ADDRESS_FIRST		0x00c4
+#define TEGRA_VI_VB0_BASE_ADDRESS_FIRST			0x00c8
+#define TEGRA_VI_VB0_START_ADDRESS_U			0x00cc
+#define TEGRA_VI_VB0_BASE_ADDRESS_U			0x00d0
+#define TEGRA_VI_VB0_START_ADDRESS_V			0x00d4
+#define TEGRA_VI_VB0_BASE_ADDRESS_V			0x00d8
+
+#define TEGRA_VI_FIRST_OUTPUT_FRAME_SIZE		0x00e0
+#define       VI_FIRST_OUTPUT_FRAME_HEIGHT_SFT		16
+#define       VI_FIRST_OUTPUT_FRAME_WIDTH_SFT		0
+
+#define TEGRA_VI_VB0_COUNT_FIRST			0x00e4
+
+#define TEGRA_VI_VB0_SIZE_FIRST				0x00e8
+#define       VI_VB0_SIZE_FIRST_V_SFT			16
+#define       VI_VB0_SIZE_FIRST_H_SFT			0
+
+#define TEGRA_VI_VB0_BUFFER_STRIDE_FIRST		0x00ec
+#define       VI_VB0_BUFFER_STRIDE_FIRST_CHROMA_SFT	30
+#define       VI_VB0_BUFFER_STRIDE_FIRST_LUMA_SFT	0
+
+#define TEGRA_VI_H_LPF_CONTROL				0x0108
+#define       VI_H_LPF_CONTROL_CHROMA_SFT		16
+#define       VI_H_LPF_CONTROL_LUMA_SFT			0
+
+#define TEGRA_VI_H_DOWNSCALE_CONTROL			0x010c
+#define TEGRA_VI_V_DOWNSCALE_CONTROL			0x0110
+
+#define TEGRA_VI_VIP_INPUT_STATUS			0x0144
+
+#define TEGRA_VI_VI_DATA_INPUT_CONTROL			0x0168
+#define       VI_DATA_INPUT_SFT				0 /* [11:0] = mask pin inputs to VI core */
+
+#define TEGRA_VI_PIN_INPUT_ENABLE			0x016c
+#define       VI_PIN_INPUT_VSYNC			BIT(14)
+#define       VI_PIN_INPUT_HSYNC			BIT(13)
+#define       VI_PIN_INPUT_VD_SFT			0 /* [11:0] = data bin N input enable */
+
+#define TEGRA_VI_PIN_INVERSION				0x0174
+#define       VI_PIN_INVERSION_VSYNC_ACTIVE_HIGH	BIT(1)
+#define       VI_PIN_INVERSION_HSYNC_ACTIVE_HIGH	BIT(0)
+
+#define TEGRA_VI_CAMERA_CONTROL				0x01a0
+#define       VI_CAMERA_CONTROL_STOP_CAPTURE		BIT(2)
+#define       VI_CAMERA_CONTROL_TEST_MODE		BIT(1)
+#define       VI_CAMERA_CONTROL_VIP_ENABLE		BIT(0)
+
+#define TEGRA_VI_VI_ENABLE				0x01a4
+#define       VI_VI_ENABLE_SW_FLOW_CONTROL_OUT1		BIT(1)
+#define       VI_VI_ENABLE_FIRST_OUTPUT_TO_MEM_DISABLE	BIT(0)
+
+#define TEGRA_VI_VI_RAISE				0x01ac
+#define       VI_VI_RAISE_ON_EDGE			BIT(0)
+
+/* --------------------------------------------------------------------------
+ * VI
+ */
+
+static void tegra20_vi_write(struct tegra_vi_channel *chan, unsigned int addr, u32 val)
+{
+	writel(val, chan->vi->iomem + addr);
+}
+
+/*
+ * Get the main input format (YUV/RGB...) and the YUV variant as values to
+ * be written into registers for the current VI input mbus code.
+ */
+static void tegra20_vi_get_input_formats(struct tegra_vi_channel *chan,
+					 unsigned int *main_input_format,
+					 unsigned int *yuv_input_format)
+{
+	unsigned int input_mbus_code = chan->fmtinfo->code;
+
+	(*main_input_format) = VI_INPUT_INPUT_FORMAT_YUV422;
+
+	switch (input_mbus_code) {
+	case MEDIA_BUS_FMT_UYVY8_2X8:
+		(*yuv_input_format) = VI_INPUT_YUV_INPUT_FORMAT_UYVY;
+		break;
+	case MEDIA_BUS_FMT_VYUY8_2X8:
+		(*yuv_input_format) = VI_INPUT_YUV_INPUT_FORMAT_VYUY;
+		break;
+	case MEDIA_BUS_FMT_YUYV8_2X8:
+		(*yuv_input_format) = VI_INPUT_YUV_INPUT_FORMAT_YUYV;
+		break;
+	case MEDIA_BUS_FMT_YVYU8_2X8:
+		(*yuv_input_format) = VI_INPUT_YUV_INPUT_FORMAT_YVYU;
+		break;
+	}
+}
+
+/*
+ * Get the main output format (YUV/RGB...) and the YUV variant as values to
+ * be written into registers for the current VI output pixel format.
+ */
+static void tegra20_vi_get_output_formats(struct tegra_vi_channel *chan,
+					  unsigned int *main_output_format,
+					  unsigned int *yuv_output_format)
+{
+	u32 output_fourcc = chan->format.pixelformat;
+
+	/* Default to YUV422 non-planar (U8Y8V8Y8) after downscaling */
+	(*main_output_format) = VI_OUTPUT_OUTPUT_FORMAT_YUV422POST;
+	(*yuv_output_format) = VI_OUTPUT_YUV_OUTPUT_FORMAT_UYVY;
+
+	switch (output_fourcc) {
+	case V4L2_PIX_FMT_UYVY:
+		(*yuv_output_format) = VI_OUTPUT_YUV_OUTPUT_FORMAT_UYVY;
+		break;
+	case V4L2_PIX_FMT_VYUY:
+		(*yuv_output_format) = VI_OUTPUT_YUV_OUTPUT_FORMAT_VYUY;
+		break;
+	case V4L2_PIX_FMT_YUYV:
+		(*yuv_output_format) = VI_OUTPUT_YUV_OUTPUT_FORMAT_YUYV;
+		break;
+	case V4L2_PIX_FMT_YVYU:
+		(*yuv_output_format) = VI_OUTPUT_YUV_OUTPUT_FORMAT_YVYU;
+		break;
+	case V4L2_PIX_FMT_YUV420:
+	case V4L2_PIX_FMT_YVU420:
+		(*main_output_format) = VI_OUTPUT_OUTPUT_FORMAT_YUV420PLANAR;
+		break;
+	}
+}
+
+/*
+ * Make the VI to be accessible (needed on Tegra20).
+ *
+ * This function writes an unknown bit into an unknown register. The code
+ * comes from a downstream 3.1 kernel that has a working VIP driver for
+ * Tegra20, and removing it makes the VI completely unaccessible. It should
+ * be rewritten and possibly moved elsewhere, but the appropriate location
+ * and implementation is unknown due to a total lack of documentation.
+ */
+static int tegra20_vi_enable(struct tegra_vi *vi, bool on)
+{
+	/* from arch/arm/mach-tegra/iomap.h */
+	const phys_addr_t TEGRA_APB_MISC_BASE = 0x70000000;
+	const unsigned long reg_offset = 0x42c;
+	void __iomem *apb_misc;
+	u32 val;
+
+	apb_misc = ioremap(TEGRA_APB_MISC_BASE, PAGE_SIZE);
+	if (!apb_misc)
+		apb_misc = ERR_PTR(-ENOENT);
+	if (IS_ERR(apb_misc))
+		return dev_err_probe(vi->dev, PTR_ERR(apb_misc), "cannot access APB_MISC");
+
+	val = readl(apb_misc + reg_offset);
+	val &= ~BIT(0);
+	val |= on ? BIT(0) : 0;
+	writel(val, apb_misc + reg_offset);
+	iounmap(apb_misc);
+
+	return 0;
+}
+
+static int tegra20_channel_host1x_syncpt_init(struct tegra_vi_channel *chan)
+{
+	struct tegra_vi *vi = chan->vi;
+	struct host1x_syncpt *out_sp;
+
+	out_sp = host1x_syncpt_request(&vi->client, HOST1X_SYNCPT_CLIENT_MANAGED);
+	if (!out_sp)
+		return dev_err_probe(vi->dev, -ENOMEM, "failed to request syncpoint\n");
+
+	chan->mw_ack_sp[0] = out_sp;
+
+	return 0;
+}
+
+static void tegra20_channel_host1x_syncpt_free(struct tegra_vi_channel *chan)
+{
+	host1x_syncpt_put(chan->mw_ack_sp[0]);
+}
+
+static void tegra20_fmt_align(struct v4l2_pix_format *pix, unsigned int bpp)
+{
+	pix->width  = clamp(pix->width,  TEGRA20_MIN_WIDTH,  TEGRA20_MAX_WIDTH);
+	pix->height = clamp(pix->height, TEGRA20_MIN_HEIGHT, TEGRA20_MAX_HEIGHT);
+
+	switch (pix->pixelformat) {
+	case V4L2_PIX_FMT_UYVY:
+	case V4L2_PIX_FMT_VYUY:
+	case V4L2_PIX_FMT_YUYV:
+	case V4L2_PIX_FMT_YVYU:
+		pix->bytesperline = roundup(pix->width, 2) * 2;
+		pix->sizeimage = roundup(pix->width, 2) * 2 * pix->height;
+		break;
+	case V4L2_PIX_FMT_YUV420:
+	case V4L2_PIX_FMT_YVU420:
+		pix->bytesperline = roundup(pix->width, 8);
+		pix->sizeimage = roundup(pix->width, 8) * pix->height * 3 / 2;
+		break;
+	}
+}
+
+/*
+ * Compute buffer offsets once per stream so that
+ * tegra20_channel_vi_buffer_setup() only has to do very simple maths for
+ * each buffer.
+ */
+static void tegra20_channel_queue_setup(struct tegra_vi_channel *chan)
+{
+	unsigned int stride = chan->format.bytesperline;
+	unsigned int height = chan->format.height;
+
+	chan->start_offset = 0;
+
+	switch (chan->format.pixelformat) {
+	case V4L2_PIX_FMT_UYVY:
+	case V4L2_PIX_FMT_VYUY:
+	case V4L2_PIX_FMT_YUYV:
+	case V4L2_PIX_FMT_YVYU:
+		if (chan->vflip)
+			chan->start_offset += stride * (height - 1);
+		if (chan->hflip)
+			chan->start_offset += stride - 1;
+		break;
+
+	case V4L2_PIX_FMT_YUV420:
+	case V4L2_PIX_FMT_YVU420:
+		chan->addr_offset_u = stride * height;
+		chan->addr_offset_v = chan->addr_offset_u + stride * height / 4;
+
+		/* For YVU420, we swap the locations of the U and V planes. */
+		if (chan->format.pixelformat == V4L2_PIX_FMT_YVU420) {
+			unsigned long temp;
+
+			temp = chan->addr_offset_u;
+			chan->addr_offset_u = chan->addr_offset_v;
+			chan->addr_offset_v = temp;
+		}
+
+		chan->start_offset_u = chan->addr_offset_u;
+		chan->start_offset_v = chan->addr_offset_v;
+
+		if (chan->vflip) {
+			chan->start_offset   += stride * (height - 1);
+			chan->start_offset_u += (stride / 2) * ((height / 2) - 1);
+			chan->start_offset_v += (stride / 2) * ((height / 2) - 1);
+		}
+		if (chan->hflip) {
+			chan->start_offset   += stride - 1;
+			chan->start_offset_u += (stride / 2) - 1;
+			chan->start_offset_v += (stride / 2) - 1;
+		}
+		break;
+	}
+}
+
+static void release_buffer(struct tegra_vi_channel *chan,
+			   struct tegra_channel_buffer *buf,
+			   enum vb2_buffer_state state)
+{
+	struct vb2_v4l2_buffer *vb = &buf->buf;
+
+	vb->sequence = chan->sequence++;
+	vb->field = V4L2_FIELD_NONE;
+	vb->vb2_buf.timestamp = ktime_get_ns();
+	vb2_buffer_done(&vb->vb2_buf, state);
+}
+
+static void tegra20_channel_vi_buffer_setup(struct tegra_vi_channel *chan,
+					    struct tegra_channel_buffer *buf)
+{
+	dma_addr_t base = buf->addr;
+
+	switch (chan->fmtinfo->fourcc) {
+	case V4L2_PIX_FMT_YUV420:
+	case V4L2_PIX_FMT_YVU420:
+		tegra20_vi_write(chan, TEGRA_VI_VB0_BASE_ADDRESS_U,  base + chan->addr_offset_u);
+		tegra20_vi_write(chan, TEGRA_VI_VB0_START_ADDRESS_U, base + chan->start_offset_u);
+		tegra20_vi_write(chan, TEGRA_VI_VB0_BASE_ADDRESS_V,  base + chan->addr_offset_v);
+		tegra20_vi_write(chan, TEGRA_VI_VB0_START_ADDRESS_V, base + chan->start_offset_v);
+		fallthrough;
+
+	case V4L2_PIX_FMT_UYVY:
+	case V4L2_PIX_FMT_VYUY:
+	case V4L2_PIX_FMT_YUYV:
+	case V4L2_PIX_FMT_YVYU:
+		tegra20_vi_write(chan, TEGRA_VI_VB0_BASE_ADDRESS_FIRST,  base);
+		tegra20_vi_write(chan, TEGRA_VI_VB0_START_ADDRESS_FIRST, base + chan->start_offset);
+		break;
+	}
+}
+
+static int tegra20_channel_capture_frame(struct tegra_vi_channel *chan,
+					 struct tegra_channel_buffer *buf)
+{
+	int err;
+
+	chan->next_out_sp_idx++;
+
+	tegra20_channel_vi_buffer_setup(chan, buf);
+
+	tegra20_vi_write(chan, TEGRA_VI_CAMERA_CONTROL, VI_CAMERA_CONTROL_VIP_ENABLE);
+
+	/* Wait for syncpt counter to reach frame start event threshold */
+	err = host1x_syncpt_wait(chan->mw_ack_sp[0], chan->next_out_sp_idx,
+				 TEGRA_VI_SYNCPT_WAIT_TIMEOUT, NULL);
+	if (err) {
+		host1x_syncpt_incr(chan->mw_ack_sp[0]);
+		dev_err_ratelimited(&chan->video.dev, "frame start syncpt timeout: %d\n", err);
+		release_buffer(chan, buf, VB2_BUF_STATE_ERROR);
+		return err;
+	}
+
+	tegra20_vi_write(chan, TEGRA_VI_CAMERA_CONTROL,
+			 VI_CAMERA_CONTROL_STOP_CAPTURE | VI_CAMERA_CONTROL_VIP_ENABLE);
+
+	release_buffer(chan, buf, VB2_BUF_STATE_DONE);
+
+	return 0;
+}
+
+static int tegra20_chan_capture_kthread_start(void *data)
+{
+	struct tegra_vi_channel *chan = data;
+	struct tegra_channel_buffer *buf;
+	unsigned int retries = 0;
+	int err = 0;
+
+	while (1) {
+		/*
+		 * Source is not streaming if error is non-zero.
+		 * So, do not dequeue buffers on error and let the thread sleep
+		 * till kthread stop signal is received.
+		 */
+		wait_event_interruptible(chan->start_wait,
+					 kthread_should_stop() ||
+					 (!list_empty(&chan->capture) && !err));
+
+		if (kthread_should_stop())
+			break;
+
+		/* dequeue the buffer and start capture */
+		spin_lock(&chan->start_lock);
+		if (list_empty(&chan->capture)) {
+			spin_unlock(&chan->start_lock);
+			continue;
+		}
+
+		buf = list_first_entry(&chan->capture, struct tegra_channel_buffer, queue);
+		list_del_init(&buf->queue);
+		spin_unlock(&chan->start_lock);
+
+		err = tegra20_channel_capture_frame(chan, buf);
+		if (!err) {
+			retries = 0;
+			continue;
+		}
+
+		if (retries++ > chan->syncpt_timeout_retry)
+			vb2_queue_error(&chan->queue);
+		else
+			err = 0;
+	}
+
+	return 0;
+}
+
+static void tegra20_camera_capture_setup(struct tegra_vi_channel *chan)
+{
+	u32 output_fourcc = chan->format.pixelformat;
+	int width  = chan->format.width;
+	int height = chan->format.height;
+	int stride_l = chan->format.bytesperline;
+	int stride_c = (output_fourcc == V4L2_PIX_FMT_YUV420 ||
+			output_fourcc == V4L2_PIX_FMT_YVU420) ? 1 : 0;
+	int main_output_format;
+	int yuv_output_format;
+
+	tegra20_vi_get_output_formats(chan, &main_output_format, &yuv_output_format);
+
+	/*
+	 * Set up low pass filter.  Use 0x240 for chromaticity and 0x240
+	 * for luminance, which is the default and means not to touch
+	 * anything.
+	 */
+	tegra20_vi_write(chan, TEGRA_VI_H_LPF_CONTROL,
+			 0x0240 << VI_H_LPF_CONTROL_LUMA_SFT |
+			 0x0240 << VI_H_LPF_CONTROL_CHROMA_SFT);
+
+	/* Set up raise-on-edge, so we get an interrupt on end of frame. */
+	tegra20_vi_write(chan, TEGRA_VI_VI_RAISE, VI_VI_RAISE_ON_EDGE);
+
+	tegra20_vi_write(chan, TEGRA_VI_VI_FIRST_OUTPUT_CONTROL,
+			 (chan->vflip ? VI_OUTPUT_V_DIRECTION : 0) |
+			 (chan->hflip ? VI_OUTPUT_H_DIRECTION : 0) |
+			 yuv_output_format << VI_OUTPUT_YUV_OUTPUT_FORMAT_SFT |
+			 main_output_format << VI_OUTPUT_OUTPUT_FORMAT_SFT);
+
+	/* Set up frame size */
+	tegra20_vi_write(chan, TEGRA_VI_FIRST_OUTPUT_FRAME_SIZE,
+			 height << VI_FIRST_OUTPUT_FRAME_HEIGHT_SFT |
+			 width  << VI_FIRST_OUTPUT_FRAME_WIDTH_SFT);
+
+	/* First output memory enabled */
+	tegra20_vi_write(chan, TEGRA_VI_VI_ENABLE, 0);
+
+	/* Set the number of frames in the buffer */
+	tegra20_vi_write(chan, TEGRA_VI_VB0_COUNT_FIRST, 1);
+
+	/* Set up buffer frame size */
+	tegra20_vi_write(chan, TEGRA_VI_VB0_SIZE_FIRST,
+			 height << VI_VB0_SIZE_FIRST_V_SFT |
+			 width  << VI_VB0_SIZE_FIRST_H_SFT);
+
+	tegra20_vi_write(chan, TEGRA_VI_VB0_BUFFER_STRIDE_FIRST,
+			 stride_l << VI_VB0_BUFFER_STRIDE_FIRST_LUMA_SFT |
+			 stride_c << VI_VB0_BUFFER_STRIDE_FIRST_CHROMA_SFT);
+
+	tegra20_vi_write(chan, TEGRA_VI_VI_ENABLE, 0);
+}
+
+static int tegra20_vi_start_streaming(struct vb2_queue *vq, u32 count)
+{
+	struct tegra_vi_channel *chan = vb2_get_drv_priv(vq);
+	struct media_pipeline *pipe = &chan->video.pipe;
+	int err;
+
+	chan->next_out_sp_idx = host1x_syncpt_read(chan->mw_ack_sp[0]);
+
+	err = video_device_pipeline_start(&chan->video, pipe);
+	if (err)
+		goto error_pipeline_start;
+
+	tegra20_camera_capture_setup(chan);
+
+	err = tegra_channel_set_stream(chan, true);
+	if (err)
+		goto error_set_stream;
+
+	chan->sequence = 0;
+
+	chan->kthread_start_capture = kthread_run(tegra20_chan_capture_kthread_start,
+						  chan, "%s:0", chan->video.name);
+	if (IS_ERR(chan->kthread_start_capture)) {
+		err = PTR_ERR(chan->kthread_start_capture);
+		chan->kthread_start_capture = NULL;
+		dev_err_probe(&chan->video.dev, err, "failed to run capture kthread\n");
+		goto error_kthread_start;
+	}
+
+	return 0;
+
+error_kthread_start:
+	tegra_channel_set_stream(chan, false);
+error_set_stream:
+	video_device_pipeline_stop(&chan->video);
+error_pipeline_start:
+	tegra_channel_release_buffers(chan, VB2_BUF_STATE_QUEUED);
+
+	return err;
+}
+
+static void tegra20_vi_stop_streaming(struct vb2_queue *vq)
+{
+	struct tegra_vi_channel *chan = vb2_get_drv_priv(vq);
+
+	if (chan->kthread_start_capture) {
+		kthread_stop(chan->kthread_start_capture);
+		chan->kthread_start_capture = NULL;
+	}
+
+	tegra_channel_release_buffers(chan, VB2_BUF_STATE_ERROR);
+	tegra_channel_set_stream(chan, false);
+	video_device_pipeline_stop(&chan->video);
+}
+
+static const struct tegra_vi_ops tegra20_vi_ops = {
+	.vi_enable = tegra20_vi_enable,
+	.channel_host1x_syncpt_init = tegra20_channel_host1x_syncpt_init,
+	.channel_host1x_syncpt_free = tegra20_channel_host1x_syncpt_free,
+	.vi_fmt_align = tegra20_fmt_align,
+	.channel_queue_setup = tegra20_channel_queue_setup,
+	.vi_start_streaming = tegra20_vi_start_streaming,
+	.vi_stop_streaming = tegra20_vi_stop_streaming,
+};
+
+#define TEGRA20_VIDEO_FMT(MBUS_CODE, BPP, FOURCC)	\
+{							\
+	.code    = MEDIA_BUS_FMT_##MBUS_CODE,		\
+	.bpp     = BPP,					\
+	.fourcc  = V4L2_PIX_FMT_##FOURCC,		\
+}
+
+static const struct tegra_video_format tegra20_video_formats[] = {
+	TEGRA20_VIDEO_FMT(UYVY8_2X8, 2, UYVY),
+	TEGRA20_VIDEO_FMT(VYUY8_2X8, 2, VYUY),
+	TEGRA20_VIDEO_FMT(YUYV8_2X8, 2, YUYV),
+	TEGRA20_VIDEO_FMT(YVYU8_2X8, 2, YVYU),
+	TEGRA20_VIDEO_FMT(UYVY8_2X8, 1, YUV420),
+	TEGRA20_VIDEO_FMT(UYVY8_2X8, 1, YVU420),
+};
+
+const struct tegra_vi_soc tegra20_vi_soc = {
+	.video_formats = tegra20_video_formats,
+	.nformats = ARRAY_SIZE(tegra20_video_formats),
+	.default_video_format = &tegra20_video_formats[0],
+	.ops = &tegra20_vi_ops,
+	.vi_max_channels = 1, /* parallel input (VIP) */
+	.vi_max_clk_hz = 150000000,
+	.has_h_v_flip = true,
+};
+
+/* --------------------------------------------------------------------------
+ * VIP
+ */
+
+/*
+ * VIP-specific configuration for stream start.
+ *
+ * Whatever is common among VIP and CSI is done by the VI component (see
+ * tegra20_vi_start_streaming()). Here we do what is VIP-specific.
+ */
+static int tegra20_vip_start_streaming(struct tegra_vip_channel *vip_chan)
+{
+	struct tegra_vi_channel *vi_chan = v4l2_get_subdev_hostdata(&vip_chan->subdev);
+	int width  = vi_chan->format.width;
+	int height = vi_chan->format.height;
+
+	unsigned int main_input_format;
+	unsigned int yuv_input_format;
+
+	tegra20_vi_get_input_formats(vi_chan, &main_input_format, &yuv_input_format);
+
+	tegra20_vi_write(vi_chan, TEGRA_VI_VI_CORE_CONTROL, 0);
+
+	tegra20_vi_write(vi_chan, TEGRA_VI_VI_INPUT_CONTROL,
+			 VI_INPUT_VIP_INPUT_ENABLE | main_input_format | yuv_input_format);
+
+	tegra20_vi_write(vi_chan, TEGRA_VI_V_DOWNSCALE_CONTROL, 0);
+	tegra20_vi_write(vi_chan, TEGRA_VI_H_DOWNSCALE_CONTROL, 0);
+
+	tegra20_vi_write(vi_chan, TEGRA_VI_VIP_V_ACTIVE, height << VI_VIP_V_ACTIVE_PERIOD_SFT);
+	tegra20_vi_write(vi_chan, TEGRA_VI_VIP_H_ACTIVE,
+			 roundup(width, 2) << VI_VIP_H_ACTIVE_PERIOD_SFT);
+
+	/*
+	 * For VIP, D9..D2 is mapped to the video decoder's P7..P0.
+	 * Disable/mask out the other Dn wires. When not in BT656
+	 * mode we also need the V/H sync.
+	 */
+	tegra20_vi_write(vi_chan, TEGRA_VI_PIN_INPUT_ENABLE,
+			 GENMASK(9, 2) << VI_PIN_INPUT_VD_SFT |
+			 VI_PIN_INPUT_HSYNC | VI_PIN_INPUT_VSYNC);
+	tegra20_vi_write(vi_chan, TEGRA_VI_VI_DATA_INPUT_CONTROL,
+			 GENMASK(9, 2) << VI_DATA_INPUT_SFT);
+	tegra20_vi_write(vi_chan, TEGRA_VI_PIN_INVERSION, 0);
+
+	tegra20_vi_write(vi_chan, TEGRA_VI_CONT_SYNCPT_OUT_1,
+			 VI_CONT_SYNCPT_OUT_1_CONTINUOUS_SYNCPT |
+			 host1x_syncpt_id(vi_chan->mw_ack_sp[0])
+			 << VI_CONT_SYNCPT_OUT_1_SYNCPT_IDX_SFT);
+
+	tegra20_vi_write(vi_chan, TEGRA_VI_CAMERA_CONTROL, VI_CAMERA_CONTROL_STOP_CAPTURE);
+
+	return 0;
+}
+
+static const struct tegra_vip_ops tegra20_vip_ops = {
+	.vip_start_streaming = tegra20_vip_start_streaming,
+};
+
+const struct tegra_vip_soc tegra20_vip_soc = {
+	.ops = &tegra20_vip_ops,
+};
diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index d1c6877163c2..eae7b1b30b07 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -1862,6 +1862,9 @@ static int tegra_vi_remove(struct platform_device *pdev)
 }
 
 static const struct of_device_id tegra_vi_of_id_table[] = {
+#if defined(CONFIG_ARCH_TEGRA_2x_SOC)
+	{ .compatible = "nvidia,tegra20-vi",  .data = &tegra20_vi_soc },
+#endif
 #if defined(CONFIG_ARCH_TEGRA_210_SOC)
 	{ .compatible = "nvidia,tegra210-vi", .data = &tegra210_vi_soc },
 #endif
diff --git a/drivers/staging/media/tegra-video/vi.h b/drivers/staging/media/tegra-video/vi.h
index 8fa817757059..c864d4ef81a5 100644
--- a/drivers/staging/media/tegra-video/vi.h
+++ b/drivers/staging/media/tegra-video/vi.h
@@ -292,6 +292,9 @@ struct tegra_video_format {
 	u32 fourcc;
 };
 
+#if defined(CONFIG_ARCH_TEGRA_2x_SOC)
+extern const struct tegra_vi_soc tegra20_vi_soc;
+#endif
 #if defined(CONFIG_ARCH_TEGRA_210_SOC)
 extern const struct tegra_vi_soc tegra210_vi_soc;
 #endif
diff --git a/drivers/staging/media/tegra-video/video.c b/drivers/staging/media/tegra-video/video.c
index d966b319553f..074ad0dc56ca 100644
--- a/drivers/staging/media/tegra-video/video.c
+++ b/drivers/staging/media/tegra-video/video.c
@@ -123,6 +123,10 @@ static int host1x_video_remove(struct host1x_device *dev)
 }
 
 static const struct of_device_id host1x_video_subdevs[] = {
+#if defined(CONFIG_ARCH_TEGRA_2x_SOC)
+	{ .compatible = "nvidia,tegra20-vip", },
+	{ .compatible = "nvidia,tegra20-vi", },
+#endif
 #if defined(CONFIG_ARCH_TEGRA_210_SOC)
 	{ .compatible = "nvidia,tegra210-csi", },
 	{ .compatible = "nvidia,tegra210-vi", },
@@ -141,6 +145,7 @@ static struct host1x_driver host1x_video_driver = {
 
 static struct platform_driver * const drivers[] = {
 	&tegra_csi_driver,
+	&tegra_vip_driver,
 	&tegra_vi_driver,
 };
 
diff --git a/drivers/staging/media/tegra-video/video.h b/drivers/staging/media/tegra-video/video.h
index 1e9be1474a9c..7275affa6558 100644
--- a/drivers/staging/media/tegra-video/video.h
+++ b/drivers/staging/media/tegra-video/video.h
@@ -24,5 +24,6 @@ int tegra_v4l2_nodes_setup_tpg(struct tegra_video_device *vid);
 void tegra_v4l2_nodes_cleanup_tpg(struct tegra_video_device *vid);
 
 extern struct platform_driver tegra_vi_driver;
+extern struct platform_driver tegra_vip_driver;
 extern struct platform_driver tegra_csi_driver;
 #endif
diff --git a/drivers/staging/media/tegra-video/vip.c b/drivers/staging/media/tegra-video/vip.c
new file mode 100644
index 000000000000..a282e4b1a48e
--- /dev/null
+++ b/drivers/staging/media/tegra-video/vip.c
@@ -0,0 +1,290 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Parallel video capture module (VIP) for the Tegra VI.
+ *
+ * This file implements the VIP-specific infrastructure.
+ *
+ * Copyright (C) 2022 SKIDATA GmbH
+ * Author: Luca Ceresoli <luca.ceresoli@bootlin.com>
+ */
+
+#include <linux/device.h>
+#include <linux/host1x.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_graph.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+
+#include <media/v4l2-fwnode.h>
+
+#include "vip.h"
+
+static inline struct tegra_vip *host1x_client_to_vip(struct host1x_client *client)
+{
+	return container_of(client, struct tegra_vip, client);
+}
+
+static inline struct tegra_vip_channel *subdev_to_vip_channel(struct v4l2_subdev *subdev)
+{
+	return container_of(subdev, struct tegra_vip_channel, subdev);
+}
+
+static inline struct tegra_vip *vip_channel_to_vip(struct tegra_vip_channel *chan)
+{
+	return container_of(chan, struct tegra_vip, chan);
+}
+
+/* Find the previous subdev in the pipeline (i.e. the one connected to our sink pad) */
+static struct v4l2_subdev *tegra_vip_channel_get_prev_subdev(struct tegra_vip_channel *chan)
+{
+	struct media_pad *remote_pad;
+
+	remote_pad = media_pad_remote_pad_first(&chan->pads[TEGRA_VIP_PAD_SINK]);
+	if (!remote_pad)
+		return NULL;
+
+	return media_entity_to_v4l2_subdev(remote_pad->entity);
+}
+
+static int tegra_vip_enable_stream(struct v4l2_subdev *subdev)
+{
+	struct tegra_vip_channel *vip_chan = subdev_to_vip_channel(subdev);
+	struct tegra_vip *vip = vip_channel_to_vip(vip_chan);
+	struct v4l2_subdev *prev_subdev = tegra_vip_channel_get_prev_subdev(vip_chan);
+	int err;
+
+	err = pm_runtime_resume_and_get(vip->dev);
+	if (err)
+		return dev_err_probe(vip->dev, err, "failed to get runtime PM\n");
+
+	err = vip->soc->ops->vip_start_streaming(vip_chan);
+	if (err < 0)
+		goto err_start_streaming;
+
+	err = v4l2_subdev_call(prev_subdev, video, s_stream, true);
+	if (err < 0 && err != -ENOIOCTLCMD)
+		goto err_prev_subdev_start_stream;
+
+	return 0;
+
+err_prev_subdev_start_stream:
+err_start_streaming:
+	pm_runtime_put(vip->dev);
+	return err;
+}
+
+static int tegra_vip_disable_stream(struct v4l2_subdev *subdev)
+{
+	struct tegra_vip_channel *vip_chan = subdev_to_vip_channel(subdev);
+	struct tegra_vip *vip = vip_channel_to_vip(vip_chan);
+	struct v4l2_subdev *prev_subdev = tegra_vip_channel_get_prev_subdev(vip_chan);
+
+	v4l2_subdev_call(prev_subdev, video, s_stream, false);
+
+	pm_runtime_put(vip->dev);
+
+	return 0;
+}
+
+static int tegra_vip_s_stream(struct v4l2_subdev *subdev, int enable)
+{
+	int err;
+
+	if (enable)
+		err = tegra_vip_enable_stream(subdev);
+	else
+		err = tegra_vip_disable_stream(subdev);
+
+	return err;
+}
+
+static const struct v4l2_subdev_video_ops tegra_vip_video_ops = {
+	.s_stream = tegra_vip_s_stream,
+};
+
+static const struct v4l2_subdev_ops tegra_vip_ops = {
+	.video  = &tegra_vip_video_ops,
+};
+
+static int tegra_vip_channel_of_parse(struct tegra_vip *vip)
+{
+	struct device *dev = vip->dev;
+	struct device_node *np = dev->of_node;
+	struct v4l2_fwnode_endpoint v4l2_ep = {
+		.bus_type = V4L2_MBUS_PARALLEL
+	};
+	struct fwnode_handle *fwh;
+	struct device_node *ep;
+	unsigned int num_pads;
+	int err;
+
+	dev_dbg(dev, "Parsing %pOF", np);
+
+	ep = of_graph_get_endpoint_by_regs(np, 0, 0);
+	if (!ep) {
+		err = -EINVAL;
+		dev_err_probe(dev, err, "%pOF: error getting endpoint node\n", np);
+		goto err_node_put;
+	}
+
+	fwh = of_fwnode_handle(ep);
+	err = v4l2_fwnode_endpoint_parse(fwh, &v4l2_ep);
+	of_node_put(ep);
+	if (err) {
+		dev_err_probe(dev, err, "%pOF: failed to parse v4l2 endpoint\n", np);
+		goto err_node_put;
+	}
+
+	num_pads = of_graph_get_endpoint_count(np);
+	if (num_pads != TEGRA_VIP_PADS_NUM) {
+		err = -EINVAL;
+		dev_err_probe(dev, err, "%pOF: need 2 pads, got %d\n", np, num_pads);
+		goto err_node_put;
+	}
+
+	vip->chan.of_node = of_node_get(np);
+	vip->chan.pads[TEGRA_VIP_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
+	vip->chan.pads[TEGRA_VIP_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
+
+	return 0;
+
+err_node_put:
+	of_node_put(np);
+	return err;
+}
+
+static int tegra_vip_channel_init(struct tegra_vip *vip)
+{
+	struct v4l2_subdev *subdev;
+	int err;
+
+	subdev = &vip->chan.subdev;
+	v4l2_subdev_init(subdev, &tegra_vip_ops);
+	subdev->dev = vip->dev;
+	snprintf(subdev->name, V4L2_SUBDEV_NAME_SIZE, "%s",
+		 kbasename(vip->chan.of_node->full_name));
+
+	v4l2_set_subdevdata(subdev, &vip->chan);
+	subdev->fwnode = of_fwnode_handle(vip->chan.of_node);
+	subdev->entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
+
+	err = media_entity_pads_init(&subdev->entity, TEGRA_VIP_PADS_NUM, vip->chan.pads);
+	if (err)
+		return dev_err_probe(vip->dev, err, "failed to initialize media entity\n");
+
+	err = v4l2_async_register_subdev(subdev);
+	if (err) {
+		dev_err_probe(vip->dev, err, "failed to register subdev\n");
+		goto err_register_subdev;
+	}
+
+	return 0;
+
+err_register_subdev:
+	media_entity_cleanup(&subdev->entity);
+	return err;
+}
+
+static int tegra_vip_init(struct host1x_client *client)
+{
+	struct tegra_vip *vip = host1x_client_to_vip(client);
+	int err;
+
+	err = tegra_vip_channel_of_parse(vip);
+	if (err)
+		return err;
+
+	err = tegra_vip_channel_init(vip);
+	if (err)
+		goto err_init;
+
+	return 0;
+
+err_init:
+	of_node_put(vip->chan.of_node);
+	return err;
+}
+
+static int tegra_vip_exit(struct host1x_client *client)
+{
+	struct tegra_vip *vip = host1x_client_to_vip(client);
+	struct v4l2_subdev *subdev = &vip->chan.subdev;
+
+	v4l2_async_unregister_subdev(subdev);
+	media_entity_cleanup(&subdev->entity);
+	of_node_put(vip->chan.of_node);
+
+	return 0;
+}
+
+static const struct host1x_client_ops vip_client_ops = {
+	.init = tegra_vip_init,
+	.exit = tegra_vip_exit,
+};
+
+static int tegra_vip_probe(struct platform_device *pdev)
+{
+	struct tegra_vip *vip;
+	int err;
+
+	dev_dbg(&pdev->dev, "Probing VIP \"%s\" from %pOF\n", pdev->name, pdev->dev.of_node);
+
+	vip = devm_kzalloc(&pdev->dev, sizeof(*vip), GFP_KERNEL);
+	if (!vip)
+		return -ENOMEM;
+
+	vip->soc = of_device_get_match_data(&pdev->dev);
+
+	vip->dev = &pdev->dev;
+	platform_set_drvdata(pdev, vip);
+
+	/* initialize host1x interface */
+	INIT_LIST_HEAD(&vip->client.list);
+	vip->client.ops = &vip_client_ops;
+	vip->client.dev = &pdev->dev;
+
+	err = host1x_client_register(&vip->client);
+	if (err)
+		return dev_err_probe(&pdev->dev, err, "failed to register host1x client\n");
+
+	pm_runtime_enable(&pdev->dev);
+
+	return 0;
+}
+
+static int tegra_vip_remove(struct platform_device *pdev)
+{
+	struct tegra_vip *vip = platform_get_drvdata(pdev);
+	int err;
+
+	err = host1x_client_unregister(&vip->client);
+	if (err)
+		return dev_err_probe(&pdev->dev, err, "failed to unregister host1x client\n");
+
+	pm_runtime_disable(&pdev->dev);
+
+	return 0;
+}
+
+#if defined(CONFIG_ARCH_TEGRA_2x_SOC)
+extern const struct tegra_vip_soc tegra20_vip_soc;
+#endif
+
+static const struct of_device_id tegra_vip_of_id_table[] = {
+#if defined(CONFIG_ARCH_TEGRA_2x_SOC)
+	{ .compatible = "nvidia,tegra20-vip", .data = &tegra20_vip_soc },
+#endif
+	{ }
+};
+MODULE_DEVICE_TABLE(of, tegra_vip_of_id_table);
+
+struct platform_driver tegra_vip_driver = {
+	.driver = {
+		.name		= "tegra-vip",
+		.of_match_table	= tegra_vip_of_id_table,
+	},
+	.probe			= tegra_vip_probe,
+	.remove			= tegra_vip_remove,
+};
diff --git a/drivers/staging/media/tegra-video/vip.h b/drivers/staging/media/tegra-video/vip.h
new file mode 100644
index 000000000000..e192ede83f1f
--- /dev/null
+++ b/drivers/staging/media/tegra-video/vip.h
@@ -0,0 +1,68 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2022 SKIDATA GmbH
+ * Author: Luca Ceresoli <luca.ceresoli@bootlin.com>
+ */
+
+#ifndef __TEGRA_VIP_H__
+#define __TEGRA_VIP_H__
+
+#include <media/media-entity.h>
+#include <media/v4l2-async.h>
+#include <media/v4l2-subdev.h>
+
+enum {
+	TEGRA_VIP_PAD_SINK,
+	TEGRA_VIP_PAD_SOURCE,
+	TEGRA_VIP_PADS_NUM,
+};
+
+struct tegra_vip;
+
+/**
+ * struct tegra_vip_channel - Tegra VIP (parallel video capture) channel
+ *
+ * @subdev: V4L2 subdevice associated with this channel
+ * @pads: media pads for the subdevice entity
+ * @of_node: vip device tree node
+ */
+struct tegra_vip_channel {
+	struct v4l2_subdev subdev;
+	struct media_pad pads[TEGRA_VIP_PADS_NUM];
+	struct device_node *of_node;
+};
+
+/**
+ * struct tegra_vip_ops - Tegra VIP operations
+ *
+ * @vip_start_streaming: programs vip hardware to enable streaming.
+ */
+struct tegra_vip_ops {
+	int (*vip_start_streaming)(struct tegra_vip_channel *vip_chan);
+};
+
+/**
+ * struct tegra_vip_soc - NVIDIA Tegra VIP SoC structure
+ *
+ * @ops: vip hardware operations
+ */
+struct tegra_vip_soc {
+	const struct tegra_vip_ops *ops;
+};
+
+/**
+ * struct tegra_vip - NVIDIA Tegra VIP device structure
+ *
+ * @dev: device struct
+ * @client: host1x_client struct
+ * @soc: pointer to SoC data structure
+ * @chan: the VIP channel
+ */
+struct tegra_vip {
+	struct device *dev;
+	struct host1x_client client;
+	const struct tegra_vip_soc *soc;
+	struct tegra_vip_channel chan;
+};
+
+#endif
-- 
2.34.1

Re: [RESEND PATCH v4 00/21] Add Tegra20 parallel video input capture

[Luca Ceresoli]

Hello,

On Thu,  9 Mar 2023 15:42:59 +0100
Luca Ceresoli <luca.ceresoli@bootlin.com> wrote:

> TL;DR: Resending this series with Rob's review tag added. Now all DT
> patches have at least a reviewed-by tag from Rob or Krzysztof, all the
> driver patches have one from Dmitry.

This is a gentle ping about this series. All patches have a
reviewed-by, there are no major changes since v2, and it's touching a
staging driver anyway.

I don't think there is more I can do at the moment besides pinging, but
should there be anything, I'd be glad to know! :-)

Best regards,
Luca
-- 
Luca Ceresoli, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

Re: [RESEND PATCH v4 00/21] Add Tegra20 parallel video input capture

[Hans Verkuil]

On 22/03/2023 10:14, Luca Ceresoli wrote:
> Hello,
> 
> On Thu,  9 Mar 2023 15:42:59 +0100
> Luca Ceresoli <luca.ceresoli@bootlin.com> wrote:
> 
>> TL;DR: Resending this series with Rob's review tag added. Now all DT
>> patches have at least a reviewed-by tag from Rob or Krzysztof, all the
>> driver patches have one from Dmitry.
> 
> This is a gentle ping about this series. All patches have a
> reviewed-by, there are no major changes since v2, and it's touching a
> staging driver anyway.
> 
> I don't think there is more I can do at the moment besides pinging, but
> should there be anything, I'd be glad to know! :-)

I actually started on this last week, but now I am abroad again with no
hardware access.

I hope I can resume work on it next week, because after that I am again
abroad for 10 days or so.

It's currently very high on my todo list, so I really hope I will be able
to make progress on it next week.

Regards,

	Hans