From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
To: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Cc: linux-media@vger.kernel.org,
Dave Stevenson <dave.stevenson@raspberrypi.com>,
David Plowman <david.plowman@raspberrypi.com>,
Jean-Michel Hautbois <jeanmichel.hautbois@ideasonboard.com>,
Hans Verkuil <hverkuil-cisco@xs4all.nl>,
Naushir Patuck <naush@raspberrypi.com>,
Sakari Ailus <sakari.ailus@linux.intel.com>,
kernel-list@raspberrypi.com,
linux-rpi-kernel@lists.infradead.org,
Florian Fainelli <florian.fainelli@broadcom.com>,
Ray Jui <rjui@broadcom.com>,
Scott Branden <sbranden@broadcom.com>,
bcm-kernel-feedback-list@broadcom.com
Subject: Re: [PATCH v6 02/15] media: i2c: imx219: Add internal image sink pad
Date: Mon, 4 Mar 2024 17:14:26 +0200 [thread overview]
Message-ID: <20240304151426.GB21608@pendragon.ideasonboard.com> (raw)
In-Reply-To: <275z3nycmioo737b2phuy4swhzziqyes4f3hgh5r6w2blvv5wc@ml3acqn6anzt>
Hi Jacopo,
On Mon, Mar 04, 2024 at 10:38:12AM +0100, Jacopo Mondi wrote:
> On Mon, Mar 04, 2024 at 10:13:47AM +0100, Jacopo Mondi wrote:
> > On Fri, Mar 01, 2024 at 11:32:17PM +0200, Laurent Pinchart wrote:
> > > Use the newly added internal pad API to expose the internal
> > > configuration of the sensor to userspace in a standard manner. This also
> > > paves the way for adding support for embedded data with an additional
> > > internal pad.
> > >
> > > To maintain compatibility with existing userspace that may operate on
> > > pad 0 unconditionally, keep the source pad numbered 0 and number the
> > > internal image pad 1.
> > >
> > > Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> > > ---
> > > drivers/media/i2c/imx219.c | 169 +++++++++++++++++++++++++++++--------
> > > 1 file changed, 133 insertions(+), 36 deletions(-)
> > >
> > > diff --git a/drivers/media/i2c/imx219.c b/drivers/media/i2c/imx219.c
> > > index 3878da50860e..817bf192e4d9 100644
> > > --- a/drivers/media/i2c/imx219.c
> > > +++ b/drivers/media/i2c/imx219.c
> > > @@ -140,6 +140,7 @@
> > > #define IMX219_DEFAULT_LINK_FREQ_4LANE 363000000
> > >
> > > /* IMX219 native and active pixel array size. */
> > > +#define IMX219_NATIVE_FORMAT MEDIA_BUS_FMT_SRGGB10_1X10
> > > #define IMX219_NATIVE_WIDTH 3296U
> > > #define IMX219_NATIVE_HEIGHT 2480U
> > > #define IMX219_PIXEL_ARRAY_LEFT 8U
> > > @@ -312,9 +313,15 @@ static const struct imx219_mode supported_modes[] = {
> > > },
> > > };
> > >
> > > +enum imx219_pad_ids {
> > > + IMX219_PAD_SOURCE,
> > > + IMX219_PAD_IMAGE,
> >
> > Feels a bit weird for the internal source pad to be named "Image" as
> > it will (if I understand correctly) host both the image and metadata
> > streams.
> >
> > However, I have an hard time proposing a different name, but we should
> > find something that should be used in all drivers ported to this new
> > API.
> >
> > Enough with bikeshedding anyway, this is a tiny detail.
>
> Now that I've read 5/15 I now understand why this is called "IMAGE" :)
:-)
> > > + IMX219_NUM_PADS,
> > > +};
> > > +
> > > struct imx219 {
> > > struct v4l2_subdev sd;
> > > - struct media_pad pad;
> > > + struct media_pad pads[IMX219_NUM_PADS];
> > >
> > > struct regmap *regmap;
> > > struct clk *xclk; /* system clock to IMX219 */
> > > @@ -374,7 +381,7 @@ static int imx219_set_ctrl(struct v4l2_ctrl *ctrl)
> > > int ret = 0;
> > >
> > > state = v4l2_subdev_get_locked_active_state(&imx219->sd);
> > > - format = v4l2_subdev_state_get_format(state, 0);
> > > + format = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE);
> > >
> > > if (ctrl->id == V4L2_CID_VBLANK) {
> > > int exposure_max, exposure_def;
> > > @@ -593,8 +600,8 @@ static int imx219_set_framefmt(struct imx219 *imx219,
> > > u64 bin_h, bin_v;
> > > int ret = 0;
> > >
> > > - format = v4l2_subdev_state_get_format(state, 0);
> > > - crop = v4l2_subdev_state_get_crop(state, 0);
> > > + format = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE);
> > > + crop = v4l2_subdev_state_get_crop(state, IMX219_PAD_IMAGE);
> > >
> > > switch (format->code) {
> > > case MEDIA_BUS_FMT_SRGGB8_1X8:
> > > @@ -764,10 +771,25 @@ static int imx219_enum_mbus_code(struct v4l2_subdev *sd,
> > > {
> > > struct imx219 *imx219 = to_imx219(sd);
> > >
> > > - if (code->index >= (ARRAY_SIZE(imx219_mbus_formats) / 4))
> > > - return -EINVAL;
> > > + if (code->pad == IMX219_PAD_IMAGE) {
> > > + /* The internal image pad is hardwired to the native format. */
> > > + if (code->index)
> > > + return -EINVAL;
> > >
> > > - code->code = imx219_get_format_code(imx219, imx219_mbus_formats[code->index * 4]);
> > > + code->code = IMX219_NATIVE_FORMAT;
> >
> > If you return 0 here you can spare the else {} branch. Same in the
> > function below.
> >
>
> You're reworking this in 5/15, so no need to change this and cause
> rebase conflicts.
It's true that I'm reworking it further in 05/15, but I think the change
here still makes sense, as it updates the driver to support the internal
pad properly. Beside, if I were to drop this change, then I would get a
rebase conflict :-)
> > > + } else {
> > > + /*
> > > + * On the source pad, the sensor supports multiple raw formats
> > > + * with different bit depths.
> > > + */
> > > + u32 format;
> > > +
> > > + if (code->index >= (ARRAY_SIZE(imx219_mbus_formats) / 4))
> > > + return -EINVAL;
> > > +
> > > + format = imx219_mbus_formats[code->index * 4];
> > > + code->code = imx219_get_format_code(imx219, format);
> > > + }
> > >
> > > return 0;
> > > }
> > > @@ -777,19 +799,25 @@ static int imx219_enum_frame_size(struct v4l2_subdev *sd,
> > > struct v4l2_subdev_frame_size_enum *fse)
> > > {
> > > struct imx219 *imx219 = to_imx219(sd);
> > > - u32 code;
> > >
> > > - if (fse->index >= ARRAY_SIZE(supported_modes))
> > > - return -EINVAL;
> > > + if (fse->pad == IMX219_PAD_IMAGE) {
> > > + if (fse->code != IMX219_NATIVE_FORMAT || fse->index > 0)
> > > + return -EINVAL;
> > >
> > > - code = imx219_get_format_code(imx219, fse->code);
> > > - if (fse->code != code)
> > > - return -EINVAL;
> > > + fse->min_width = IMX219_NATIVE_WIDTH;
> > > + fse->max_width = IMX219_NATIVE_WIDTH;
> > > + fse->min_height = IMX219_NATIVE_HEIGHT;
> > > + fse->max_height = IMX219_NATIVE_HEIGHT;
> > > + } else {
> > > + if (fse->code != imx219_get_format_code(imx219, fse->code) ||
> > > + fse->index >= ARRAY_SIZE(supported_modes))
> > > + return -EINVAL;
> > >
> > > - fse->min_width = supported_modes[fse->index].width;
> > > - fse->max_width = fse->min_width;
> > > - fse->min_height = supported_modes[fse->index].height;
> > > - fse->max_height = fse->min_height;
> > > + fse->min_width = supported_modes[fse->index].width;
> > > + fse->max_width = fse->min_width;
> > > + fse->min_height = supported_modes[fse->index].height;
> > > + fse->max_height = fse->min_height;
> > > + }
> > >
> > > return 0;
> > > }
> > > @@ -801,9 +829,17 @@ static int imx219_set_pad_format(struct v4l2_subdev *sd,
> > > struct imx219 *imx219 = to_imx219(sd);
> > > const struct imx219_mode *mode;
> > > struct v4l2_mbus_framefmt *format;
> > > + struct v4l2_rect *compose;
> > > struct v4l2_rect *crop;
> > > unsigned int bin_h, bin_v;
> > >
> > > + /*
> > > + * The driver is mode-based, the format can be set on the source pad
> > > + * only.
> > > + */
> > > + if (fmt->pad != IMX219_PAD_SOURCE)
> > > + return v4l2_subdev_get_fmt(sd, state, fmt);
> > > +
> > > /*
> > > * Adjust the requested format to match the closest mode. The Bayer
> > > * order varies with flips.
> > > @@ -822,22 +858,51 @@ static int imx219_set_pad_format(struct v4l2_subdev *sd,
> > > fmt->format.quantization = V4L2_QUANTIZATION_FULL_RANGE;
> > > fmt->format.xfer_func = V4L2_XFER_FUNC_NONE;
> > >
> > > - format = v4l2_subdev_state_get_format(state, 0);
> > > + /* Propagate the format through the sensor. */
> > > +
> > > + /* The image pad models the pixel array, and thus has a fixed size. */
> > > + format = v4l2_subdev_state_get_format(state, IMX219_PAD_IMAGE);
> > > *format = fmt->format;
> >
> > Is this assignment needed ?
> >
> > Isn't 'fmt' meant to be applied at pad #0 ? Also, you overwrite the
> > code and size below, do the rest of the 'struct v4l2_mbus_framefmt'
> > fields apply to pad #1 (field, colorspace, quantization etc ? If pad
> > #1 represents the pixel array, I don't think they do).
It's a shortcut to avoid setting field, colorspace, ycbcr_enc,
quantization and xfer_func manually, as there's set a few lines above in
fmt. I can set the fields manually if you prefer.
> > Also, can't the pad #1 format be initialized by .init_state() and never
> > touched again ?
They could, but then .init_state() couldn't be implemented by simply
calling imx219_set_pad_format(). I think it is clearer to store all the
format setting logic in one place, especially when adding support for
the embedded data stream.
> > > + format->code = IMX219_NATIVE_FORMAT;
> > > + format->width = IMX219_NATIVE_WIDTH;
> > > + format->height = IMX219_NATIVE_HEIGHT;
> > >
> > > /*
> > > * Use binning to maximize the crop rectangle size, and centre it in the
> > > * sensor.
> > > */
> > > - bin_h = min(IMX219_PIXEL_ARRAY_WIDTH / format->width, 2U);
> > > - bin_v = min(IMX219_PIXEL_ARRAY_HEIGHT / format->height, 2U);
> > > + bin_h = min(IMX219_PIXEL_ARRAY_WIDTH / fmt->format.width, 2U);
> > > + bin_v = min(IMX219_PIXEL_ARRAY_HEIGHT / fmt->format.height, 2U);
> > >
> > > - crop = v4l2_subdev_state_get_crop(state, 0);
> > > - crop->width = format->width * bin_h;
> > > - crop->height = format->height * bin_v;
> > > + crop = v4l2_subdev_state_get_crop(state, IMX219_PAD_IMAGE);
> > > + crop->width = fmt->format.width * bin_h;
> > > + crop->height = fmt->format.height * bin_v;
> > > crop->left = (IMX219_NATIVE_WIDTH - crop->width) / 2;
> > > crop->top = (IMX219_NATIVE_HEIGHT - crop->height) / 2;
> >
> > This is no different than before, but I now wonder if VGA is actually
> > obtained by cropping down to 1280x960 and then by a 2x2 binning, or is
> > there a 4x4 binning mode. I presume this is correct though, as this has been
> > validated by many people.
It would be worth experimenting with the /4 binning mode.
> > > + /*
> > > + * The compose rectangle models binning, its size is the sensor output
> > > + * size.
> > > + */
> > > + compose = v4l2_subdev_state_get_compose(state, IMX219_PAD_IMAGE);
> > > + compose->left = 0;
> > > + compose->top = 0;
> > > + compose->width = fmt->format.width;
> > > + compose->height = fmt->format.height;
> > > +
> > > + /*
> > > + * No mode use digital crop, the source pad crop rectangle size and
> > > + * format are thus identical to the image pad compose rectangle.
> > > + */
> > > + crop = v4l2_subdev_state_get_crop(state, IMX219_PAD_SOURCE);
> > > + crop->left = 0;
> > > + crop->top = 0;
> > > + crop->width = fmt->format.width;
> > > + crop->height = fmt->format.height;
> > > +
> > > + format = v4l2_subdev_state_get_format(state, IMX219_PAD_SOURCE);
> > > + *format = fmt->format;
> > > +
> > > if (fmt->which == V4L2_SUBDEV_FORMAT_ACTIVE) {
> > > int exposure_max;
> > > int exposure_def;
> > > @@ -874,13 +939,13 @@ static int imx219_get_selection(struct v4l2_subdev *sd,
> > > struct v4l2_subdev_state *state,
> > > struct v4l2_subdev_selection *sel)
> > > {
> > > - switch (sel->target) {
> > > - case V4L2_SEL_TGT_CROP: {
> > > - sel->r = *v4l2_subdev_state_get_crop(state, 0);
> > > - return 0;
> > > - }
> > > + struct v4l2_rect *compose;
> > >
> > > + switch (sel->target) {
> > > case V4L2_SEL_TGT_NATIVE_SIZE:
> > > + if (sel->pad != IMX219_PAD_IMAGE)
> > > + return -EINVAL;
> > > +
> > > sel->r.top = 0;
> > > sel->r.left = 0;
> > > sel->r.width = IMX219_NATIVE_WIDTH;
> > > @@ -890,11 +955,35 @@ static int imx219_get_selection(struct v4l2_subdev *sd,
> > >
> > > case V4L2_SEL_TGT_CROP_DEFAULT:
> > > case V4L2_SEL_TGT_CROP_BOUNDS:
> > > - sel->r.top = IMX219_PIXEL_ARRAY_TOP;
> > > - sel->r.left = IMX219_PIXEL_ARRAY_LEFT;
> > > - sel->r.width = IMX219_PIXEL_ARRAY_WIDTH;
> > > - sel->r.height = IMX219_PIXEL_ARRAY_HEIGHT;
> > > + switch (sel->pad) {
> > > + case IMX219_PAD_IMAGE:
> > > + sel->r.top = IMX219_PIXEL_ARRAY_TOP;
> > > + sel->r.left = IMX219_PIXEL_ARRAY_LEFT;
> > > + sel->r.width = IMX219_PIXEL_ARRAY_WIDTH;
> > > + sel->r.height = IMX219_PIXEL_ARRAY_HEIGHT;
> > > + return 0;
> > >
> > > + case IMX219_PAD_SOURCE:
> > > + compose = v4l2_subdev_state_get_compose(state,
> > > + IMX219_PAD_IMAGE);
> > > + sel->r.top = 0;
> > > + sel->r.left = 0;
> > > + sel->r.width = compose->width;
> > > + sel->r.height = compose->height;
> > > + return 0;
> > > + }
> > > +
> > > + break;
> > > +
> > > + case V4L2_SEL_TGT_CROP:
> > > + sel->r = *v4l2_subdev_state_get_crop(state, sel->pad);
> > > + return 0;
> > > +
> > > + case V4L2_SEL_TGT_COMPOSE:
> > > + if (sel->pad != IMX219_PAD_IMAGE)
> > > + return -EINVAL;
> > > +
> > > + sel->r = *v4l2_subdev_state_get_compose(state, sel->pad);
> > > return 0;
> >
> > Do we need to support TGT_COMPOSE_BOUNDS for PAD_IMAGE ? I would have
> > suggested V4L2_SEL_TGT_COMPOSE_DEFAULT too, but according to the spec
> > it does not apply to subdevices.
Good question. V4L2_SEL_TGT_COMPOSE_BOUNDS is a bit under-documented for
V4L2 subdevs. I wonder if it wouldn't be simpler for drivers to not
implement it when the compose bounds are identical to the crop rectangle
size, as that could be considered a default ?
> > > }
> > >
> > > @@ -906,7 +995,7 @@ static int imx219_init_state(struct v4l2_subdev *sd,
> > > {
> > > struct v4l2_subdev_format fmt = {
> > > .which = V4L2_SUBDEV_FORMAT_TRY,
> > > - .pad = 0,
> > > + .pad = IMX219_PAD_SOURCE,
> > > .format = {
> > > .code = MEDIA_BUS_FMT_SRGGB10_1X10,
> > > .width = supported_modes[0].width,
> >
> > Why not intialize pad#1 format here an never touch it again ? Should
> > also the pad#1 crop and compose rectangles and pad#0 crop be
> > initialized here ?
As written above, I think it's cleaner to have all the format-related
constraints in one place, especially with support for embedded data. It
may be a style preference, I'm not sure.
> > > @@ -1174,10 +1263,18 @@ static int imx219_probe(struct i2c_client *client)
> > > V4L2_SUBDEV_FL_HAS_EVENTS;
> > > imx219->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
> > >
> > > - /* Initialize source pad */
> > > - imx219->pad.flags = MEDIA_PAD_FL_SOURCE;
> > > + /*
> > > + * Initialize the pads. To preserve backward compatibility with
> > > + * userspace that used the sensor before the introduction of the
> > > + * internal image pad, the external source pad is numbered 0 and the
> > > + * internal image pad numbered 1.
> > > + */
> > > + imx219->pads[IMX219_PAD_SOURCE].flags = MEDIA_PAD_FL_SOURCE;
> > > + imx219->pads[IMX219_PAD_IMAGE].flags = MEDIA_PAD_FL_SINK
> > > + | MEDIA_PAD_FL_INTERNAL;
> > >
> > > - ret = media_entity_pads_init(&imx219->sd.entity, 1, &imx219->pad);
> > > + ret = media_entity_pads_init(&imx219->sd.entity,
> > > + ARRAY_SIZE(imx219->pads), imx219->pads);
> > > if (ret) {
> > > dev_err(dev, "failed to init entity pads: %d\n", ret);
> > > goto error_handler_free;
--
Regards,
Laurent Pinchart
next prev parent reply other threads:[~2024-03-04 15:14 UTC|newest]
Thread overview: 56+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-03-01 21:32 [PATCH 00/15] media: Add driver for the Raspberry Pi <5 CSI-2 receiver Laurent Pinchart
2024-03-01 21:32 ` [PATCH v6 01/15] media: i2c: imx219: Inline imx219_update_pad_format() in its caller Laurent Pinchart
2024-03-04 8:45 ` Jacopo Mondi
2024-03-05 16:01 ` Dave Stevenson
2024-03-01 21:32 ` [PATCH v6 02/15] media: i2c: imx219: Add internal image sink pad Laurent Pinchart
2024-03-04 9:13 ` Jacopo Mondi
2024-03-04 9:38 ` Jacopo Mondi
2024-03-04 15:14 ` Laurent Pinchart [this message]
2024-03-04 15:57 ` Jacopo Mondi
2024-03-01 21:32 ` [PATCH v6 03/15] media: i2c: imx219: Report internal routes to userspace Laurent Pinchart
2024-03-04 9:30 ` Jacopo Mondi
2024-03-04 12:22 ` Laurent Pinchart
2024-03-01 21:32 ` [PATCH v6 04/15] media: i2c: imx219: Report streams using frame descriptors Laurent Pinchart
2024-03-04 9:33 ` Jacopo Mondi
2024-03-04 15:16 ` Laurent Pinchart
2024-03-01 21:32 ` [PATCH v6 05/15] media: i2c: imx219: Add embedded data support Laurent Pinchart
2024-03-04 9:47 ` Jacopo Mondi
2024-03-04 17:22 ` Laurent Pinchart
2024-03-01 21:32 ` [PATCH v6 06/15] media: v4l: Add V4L2-PIX-FMT-Y12P format Laurent Pinchart
2024-03-04 11:11 ` Jacopo Mondi
2024-03-04 19:08 ` Laurent Pinchart
2024-03-01 21:32 ` [PATCH v6 07/15] media: v4l: Add V4L2-PIX-FMT-Y14P format Laurent Pinchart
2024-03-01 21:32 ` [PATCH v6 08/15] dt-bindings: media: Add bindings for bcm2835-unicam Laurent Pinchart
2024-03-25 18:28 ` Sakari Ailus
2024-03-25 23:02 ` Laurent Pinchart
2024-03-26 22:11 ` Sakari Ailus
2024-03-01 21:32 ` [PATCH v6 09/15] media: bcm2835-unicam: Add support for CCP2/CSI2 camera interface Laurent Pinchart
2024-03-04 17:12 ` Jacopo Mondi
2024-03-04 19:51 ` Laurent Pinchart
2024-03-05 14:56 ` Dave Stevenson
2024-03-16 23:54 ` Laurent Pinchart
2024-03-05 14:15 ` Dave Stevenson
2024-03-16 22:36 ` Laurent Pinchart
2024-03-20 12:30 ` Naushir Patuck
2024-03-21 19:57 ` Laurent Pinchart
2024-03-22 8:40 ` Jean-Michel Hautbois
2024-03-25 18:36 ` Sakari Ailus
2024-03-26 1:37 ` Laurent Pinchart
2024-03-26 1:50 ` Laurent Pinchart
2024-03-26 22:23 ` Sakari Ailus
2024-03-26 15:23 ` Dave Stevenson
2024-03-26 16:42 ` Laurent Pinchart
2024-03-26 17:01 ` Dave Stevenson
2024-03-01 21:32 ` [PATCH v6 10/15] ARM: dts: bcm2835-rpi: Move firmware-clocks from bcm2711 to bcm2835 Laurent Pinchart
2024-03-01 21:32 ` [PATCH v6 11/15] ARM: dts: bcm2835: Add Unicam CSI nodes Laurent Pinchart
2024-03-01 21:32 ` [PATCH v6 12/15] ARM: dts: bcm2711-rpi: Add pinctrl-based multiplexing for I2C0 Laurent Pinchart
2024-03-18 14:56 ` Dave Stevenson
2024-03-18 19:25 ` Laurent Pinchart
2024-03-01 21:32 ` [PATCH v6 13/15] ARM: dts: bcm2711-rpi-cm4-io: Add RTC on I2C0 Laurent Pinchart
2024-03-18 14:56 ` Dave Stevenson
2024-03-18 19:24 ` Laurent Pinchart
2024-03-01 21:32 ` [PATCH v6 14/15] ARM: dts: bcm2711-rpi-4-b: Add CAM1 regulator Laurent Pinchart
2024-03-01 21:32 ` [PATCH v6 15/15] [DNI] arm64: dts: broadcom: Add overlay for Raspberry Pi 4B IMX219 camera Laurent Pinchart
2024-03-01 21:38 ` [PATCH 00/15] media: Add driver for the Raspberry Pi <5 CSI-2 receiver Laurent Pinchart
2024-03-15 14:02 ` Florian Fainelli
2024-03-16 20:06 ` Laurent Pinchart
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