[libcamera-devel] [PATCH v8 2/6] libcamera: V4L2Device: Support v4l2 menu control

Jacopo Mondi jacopo at jmondi.org
Thu Jun 10 18:05:44 CEST 2021


Hi Hiro,

On Thu, Jun 10, 2021 at 05:25:35PM +0900, Hirokazu Honda wrote:
> This adds a support of v4l2 menu. The control info for v4l2 menu
> contains indices without names and 64bit values of querymenu.
>
> Signed-off-by: Hirokazu Honda <hiroh at chromium.org>
> Reviewed-by: Jacopo Mondi <jacopo at jmondi.org>
> Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> ---
>  include/libcamera/internal/v4l2_device.h |   5 +
>  src/libcamera/v4l2_device.cpp            | 186 +++++++++++++++--------
>  2 files changed, 127 insertions(+), 64 deletions(-)
>
> diff --git a/include/libcamera/internal/v4l2_device.h b/include/libcamera/internal/v4l2_device.h
> index b82e2a14..c318e976 100644
> --- a/include/libcamera/internal/v4l2_device.h
> +++ b/include/libcamera/internal/v4l2_device.h
> @@ -56,6 +56,11 @@ protected:
>  	int fd() const { return fd_; }
>
>  private:
> +	static ControlType v4l2CtrlType(uint32_t ctrlType);
> +	static std::unique_ptr<ControlId> v4l2ControlId(const v4l2_query_ext_ctrl &ctrl);
> +	ControlInfo v4l2ControlInfo(const v4l2_query_ext_ctrl &ctrl);
> +	ControlInfo v4l2MenuControlInfo(const v4l2_query_ext_ctrl &ctrl);
> +
>  	void listControls();
>  	void updateControls(ControlList *ctrls,
>  			    Span<const v4l2_ext_control> v4l2Ctrls);
> diff --git a/src/libcamera/v4l2_device.cpp b/src/libcamera/v4l2_device.cpp
> index b39c6266..cda3769a 100644
> --- a/src/libcamera/v4l2_device.cpp
> +++ b/src/libcamera/v4l2_device.cpp
> @@ -32,69 +32,6 @@ LOG_DEFINE_CATEGORY(V4L2)
>
>  namespace {
>
> -ControlType v4l2CtrlType(uint32_t ctrlType)
> -{
> -	switch (ctrlType) {
> -	case V4L2_CTRL_TYPE_U8:
> -		return ControlTypeByte;
> -
> -	case V4L2_CTRL_TYPE_BOOLEAN:
> -		return ControlTypeBool;
> -
> -	case V4L2_CTRL_TYPE_INTEGER:
> -		return ControlTypeInteger32;
> -
> -	case V4L2_CTRL_TYPE_INTEGER64:
> -		return ControlTypeInteger64;
> -
> -	case V4L2_CTRL_TYPE_MENU:
> -	case V4L2_CTRL_TYPE_BUTTON:
> -	case V4L2_CTRL_TYPE_BITMASK:
> -	case V4L2_CTRL_TYPE_INTEGER_MENU:
> -		/*
> -		 * More precise types may be needed, for now use a 32-bit
> -		 * integer type.
> -		 */
> -		return ControlTypeInteger32;
> -
> -	default:
> -		return ControlTypeNone;
> -	}
> -}
> -
> -std::unique_ptr<ControlId> v4l2ControlId(const v4l2_query_ext_ctrl &ctrl)
> -{
> -	const size_t len = strnlen(ctrl.name, sizeof(ctrl.name));
> -	const std::string name(static_cast<const char *>(ctrl.name), len);
> -	const ControlType type = v4l2CtrlType(ctrl.type);
> -
> -	return std::make_unique<ControlId>(ctrl.id, name, type);
> -}
> -
> -ControlInfo v4l2ControlInfo(const v4l2_query_ext_ctrl &ctrl)
> -{
> -	switch (ctrl.type) {
> -	case V4L2_CTRL_TYPE_U8:
> -		return ControlInfo(static_cast<uint8_t>(ctrl.minimum),
> -				   static_cast<uint8_t>(ctrl.maximum),
> -				   static_cast<uint8_t>(ctrl.default_value));
> -
> -	case V4L2_CTRL_TYPE_BOOLEAN:
> -		return ControlInfo(static_cast<bool>(ctrl.minimum),
> -				   static_cast<bool>(ctrl.maximum),
> -				   static_cast<bool>(ctrl.default_value));
> -
> -	case V4L2_CTRL_TYPE_INTEGER64:
> -		return ControlInfo(static_cast<int64_t>(ctrl.minimum),
> -				   static_cast<int64_t>(ctrl.maximum),
> -				   static_cast<int64_t>(ctrl.default_value));
> -
> -	default:
> -		return ControlInfo(static_cast<int32_t>(ctrl.minimum),
> -				   static_cast<int32_t>(ctrl.maximum),
> -				   static_cast<int32_t>(ctrl.default_value));
> -	}
> -}
>   } /* namespace */

Thanks for addressing my request, but now we have an empty namespace
which could be dropped.

I have a few more picky comments on the newly added documentation.
With your ack they can be applied when merging.

>
>  /**
> @@ -524,6 +461,121 @@ int V4L2Device::ioctl(unsigned long request, void *argp)
>   * \return The V4L2 device file descriptor, -1 if the device node is not open
>   */
>
> +/**
> + * \brief Retrieve ControlType for V4L2 control type

Retrieve the libcamera control type associated with the V4L2 control type

> + * \param[in] ctrlType V4L2 control type
> + *
> + * \return ControlType for \a ctrlType

The ControlType corresponding to \a ctrlType

> + */
> +ControlType V4L2Device::v4l2CtrlType(uint32_t ctrlType)
> +{
> +	switch (ctrlType) {
> +	case V4L2_CTRL_TYPE_U8:
> +		return ControlTypeByte;
> +
> +	case V4L2_CTRL_TYPE_BOOLEAN:
> +		return ControlTypeBool;
> +
> +	case V4L2_CTRL_TYPE_INTEGER:
> +		return ControlTypeInteger32;
> +
> +	case V4L2_CTRL_TYPE_INTEGER64:
> +		return ControlTypeInteger64;
> +
> +	case V4L2_CTRL_TYPE_MENU:
> +	case V4L2_CTRL_TYPE_BUTTON:
> +	case V4L2_CTRL_TYPE_BITMASK:
> +	case V4L2_CTRL_TYPE_INTEGER_MENU:
> +		/*
> +		 * More precise types may be needed, for now use a 32-bit
> +		 * integer type.
> +		 */
> +		return ControlTypeInteger32;
> +
> +	default:
> +		return ControlTypeNone;
> +	}
> +}
> +
> +/**
> + * \brief Create ControlId for v4l2_query_ext_ctrl

\brief Create a ControlId for a V4L2 control

> + * \param[in] ctrl v4l2_query_ext_ctrl

Your below description sound better:

\param[in] ctrl The v4l2_query_ext_ctrl that represents a V4L2 control

> + *
> + * \return ControlId for \a ctrl
> + */
> +std::unique_ptr<ControlId> V4L2Device::v4l2ControlId(const v4l2_query_ext_ctrl &ctrl)
> +{
> +	const size_t len = strnlen(ctrl.name, sizeof(ctrl.name));
> +	const std::string name(static_cast<const char *>(ctrl.name), len);
> +	const ControlType type = v4l2CtrlType(ctrl.type);
> +
> +	return std::make_unique<ControlId>(ctrl.id, name, type);
> +}
> +
> +/**
> + * \brief Create ControlInfo from v4l2_query_ext_ctrl
> + * \param[in] ctrl v4l2_query_ext_ctrl

Your below description sound better:

\param[in] ctrl The v4l2_query_ext_ctrl that represents a V4L2 control


> + *
> + * \return ControlInfo from \a v4l2_query_ext_ctrl

A ControlInfo created from \a ctrl

> + */
> +ControlInfo V4L2Device::v4l2ControlInfo(const v4l2_query_ext_ctrl &ctrl)
> +{
> +	switch (ctrl.type) {
> +	case V4L2_CTRL_TYPE_U8:
> +		return ControlInfo(static_cast<uint8_t>(ctrl.minimum),
> +				   static_cast<uint8_t>(ctrl.maximum),
> +				   static_cast<uint8_t>(ctrl.default_value));
> +
> +	case V4L2_CTRL_TYPE_BOOLEAN:
> +		return ControlInfo(static_cast<bool>(ctrl.minimum),
> +				   static_cast<bool>(ctrl.maximum),
> +				   static_cast<bool>(ctrl.default_value));
> +
> +	case V4L2_CTRL_TYPE_INTEGER64:
> +		return ControlInfo(static_cast<int64_t>(ctrl.minimum),
> +				   static_cast<int64_t>(ctrl.maximum),
> +				   static_cast<int64_t>(ctrl.default_value));
> +
> +	case V4L2_CTRL_TYPE_INTEGER_MENU:
> +	case V4L2_CTRL_TYPE_MENU:
> +		return v4l2MenuControlInfo(ctrl);
> +
> +	default:
> +		return ControlInfo(static_cast<int32_t>(ctrl.minimum),
> +				   static_cast<int32_t>(ctrl.maximum),
> +				   static_cast<int32_t>(ctrl.default_value));
> +	}
> +}
> +
> +/**
> + * \brief Create ControlInfo for a V4L2 menu control
> + * \param[in] ctrl The v4l2_query_ext_ctrl that represents a menu

.. a V4L2 menu control

> + *
> + * The created ControlInfo contains indices acquired by VIDIOC_QUERYMENU.
> + *
> + * \return ControlInfo for a V4L2 menu control

I would apply the same suggestion given above

> + */
> +ControlInfo V4L2Device::v4l2MenuControlInfo(const struct v4l2_query_ext_ctrl &ctrl)
> +{
> +	std::vector<ControlValue> indices;
> +	struct v4l2_querymenu menu = {};
> +	menu.id = ctrl.id;
> +
> +	if (ctrl.minimum < 0)
> +		return ControlInfo();
> +
> +	for (int32_t index = ctrl.minimum; index <= ctrl.maximum; ++index) {
> +		menu.index = index;
> +		if (ioctl(VIDIOC_QUERYMENU, &menu) != 0)
> +			continue;
> +
> +		indices.push_back(index);
> +	}
> +
> +	return ControlInfo(indices,
> +			   ControlValue(static_cast<int32_t>(ctrl.default_value)));
> +}
> +
>  /*
>   * \brief List and store information about all controls supported by the
>   * V4L2 device
> @@ -533,7 +585,6 @@ void V4L2Device::listControls()
>  	ControlInfoMap::Map ctrls;
>  	struct v4l2_query_ext_ctrl ctrl = {};
>
> -	/* \todo Add support for menu controls. */
>  	while (1) {
>  		ctrl.id |= V4L2_CTRL_FLAG_NEXT_CTRL |
>  			   V4L2_CTRL_FLAG_NEXT_COMPOUND;
> @@ -562,6 +613,9 @@ void V4L2Device::listControls()
>  			continue;
>  		}
>
> +		LOG(V4L2, Debug) << "Control: " << ctrl.name
> +				 << " (" << utils::hex(ctrl.id) << ")";
> +
>  		controlIds_.emplace_back(v4l2ControlId(ctrl));
>  		controlInfo_.emplace(ctrl.id, ctrl);
>
> @@ -630,6 +684,10 @@ void V4L2Device::updateControls(ControlList *ctrls,
>  			value.set<int64_t>(v4l2Ctrl.value64);
>  			break;
>
> +		case ControlTypeInteger32:
> +			value.set<int32_t>(v4l2Ctrl.value);
> +			break;
> +
>  		case ControlTypeByte:
>  			/*
>  			 * No action required, the VIDIOC_[GS]_EXT_CTRLS ioctl
> --
> 2.32.0.rc1.229.g3e70b5a671-goog
>


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