Commit 1b888b3c authored by Sakari Ailus's avatar Sakari Ailus Committed by Mauro Carvalho Chehab
Browse files

media: v4l: Add a helper for obtaining the link frequency 



Add a helper for obtaining the link frequency from transmitter drivers.

Signed-off-by: default avatarSakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+huawei@kernel.org>
parent 9d0a79e5

drivers/media/v4l2-core/v4l2-common.c

+33 −0
Original line number Diff line number Diff line
@@ -441,3 +441,36 @@ int v4l2_fill_pixfmt(struct v4l2_pix_format *pixfmt, u32 pixelformat, 
	return 0;

}

EXPORT_SYMBOL_GPL(v4l2_fill_pixfmt);



s64 v4l2_get_link_rate(struct v4l2_ctrl_handler *handler, unsigned int mul,

		       unsigned int div)

{

	struct v4l2_ctrl *ctrl;

	s64 freq;



	ctrl = v4l2_ctrl_find(handler, V4L2_CID_LINK_FREQ);

	if (ctrl) {

		struct v4l2_querymenu qm = { .id = V4L2_CID_LINK_FREQ };

		int ret;



		qm.index = v4l2_ctrl_g_ctrl(ctrl);



		ret = v4l2_querymenu(handler, &qm);

		if (ret)

			return -ENOENT;



		freq = qm.value;

	} else {

		if (!mul || !div)

			return -ENOENT;



		ctrl = v4l2_ctrl_find(handler, V4L2_CID_PIXEL_RATE);

		if (!ctrl)

			return -ENOENT;



		freq = div_u64(v4l2_ctrl_g_ctrl_int64(ctrl) * mul, div);

	}



	return freq > 0 ? freq : -EINVAL;

}

EXPORT_SYMBOL_GPL(v4l2_get_link_rate);

include/media/v4l2-common.h

+21 −0
Original line number Diff line number Diff line
@@ -519,6 +519,27 @@ int v4l2_fill_pixfmt(struct v4l2_pix_format *pixfmt, u32 pixelformat, 
int v4l2_fill_pixfmt_mp(struct v4l2_pix_format_mplane *pixfmt, u32 pixelformat,

			u32 width, u32 height);



/**

 * v4l2_get_link_rate - Get link rate from transmitter

 *

 * @handler: The transmitter's control handler

 * @mul: The multiplier between pixel rate and link frequency. Bits per pixel on

 *	 D-PHY, samples per clock on parallel. 0 otherwise.

 * @div: The divisor between pixel rate and link frequency. Number of data lanes

 *	 times two on D-PHY, 1 on parallel. 0 otherwise.

 *

 * This function is intended for obtaining the link frequency from the

 * transmitter sub-devices. It returns the link rate, either from the

 * V4L2_CID_LINK_FREQ control implemented by the transmitter, or value

 * calculated based on the V4L2_CID_PIXEL_RATE implemented by the transmitter.

 *

 * Returns link frequency on success, otherwise a negative error code:

 *	-ENOENT: Link frequency or pixel rate control not found

 *	-EINVAL: Invalid link frequency value

 */

s64 v4l2_get_link_rate(struct v4l2_ctrl_handler *handler, unsigned int mul,

		       unsigned int div);



static inline u64 v4l2_buffer_get_timestamp(const struct v4l2_buffer *buf)

{

	/*