Commit a68e88e2 authored by Sakari Ailus's avatar Sakari Ailus Committed by Mauro Carvalho Chehab
Browse files

media: v4l: Add a helper for setting up link-frequencies control 



Add a helper for obtaining supported link frequencies in form most drivers
need them. The result is a bitmap of supported controls.

Signed-off-by: default avatarSakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@kernel.org>
parent 45db5c21

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

+47 −0
Original line number Diff line number Diff line
@@ -585,3 +585,50 @@ u32 v4l2_fraction_to_interval(u32 numerator, u32 denominator) 
	return denominator ? numerator * multiplier / denominator : 0;

}

EXPORT_SYMBOL_GPL(v4l2_fraction_to_interval);



int v4l2_link_freq_to_bitmap(struct device *dev, const u64 *fw_link_freqs,

			     unsigned int num_of_fw_link_freqs,

			     const s64 *driver_link_freqs,

			     unsigned int num_of_driver_link_freqs,

			     unsigned long *bitmap)

{

	unsigned int i;



	*bitmap = 0;



	if (!num_of_fw_link_freqs) {

		dev_err(dev, "no link frequencies in firmware\n");

		return -ENODATA;

	}



	for (i = 0; i < num_of_fw_link_freqs; i++) {

		unsigned int j;



		for (j = 0; j < num_of_driver_link_freqs; j++) {

			if (fw_link_freqs[i] != driver_link_freqs[j])

				continue;



			dev_dbg(dev, "enabling link frequency %lld Hz\n",

				driver_link_freqs[j]);

			*bitmap |= BIT(j);

			break;

		}

	}



	if (!*bitmap) {

		dev_err(dev, "no matching link frequencies found\n");



		dev_dbg(dev, "specified in firmware:\n");

		for (i = 0; i < num_of_fw_link_freqs; i++)

			dev_dbg(dev, "\t%llu Hz\n", fw_link_freqs[i]);



		dev_dbg(dev, "driver supported:\n");

		for (i = 0; i < num_of_driver_link_freqs; i++)

			dev_dbg(dev, "\t%lld Hz\n", driver_link_freqs[i]);



		return -ENOENT;

	}



	return 0;

}

EXPORT_SYMBOL_GPL(v4l2_link_freq_to_bitmap);

include/media/v4l2-common.h

+25 −0
Original line number Diff line number Diff line
@@ -547,6 +547,31 @@ void v4l2_simplify_fraction(u32 *numerator, u32 *denominator, 
		unsigned int n_terms, unsigned int threshold);

u32 v4l2_fraction_to_interval(u32 numerator, u32 denominator);



/**

 * v4l2_link_freq_to_bitmap - Figure out platform-supported link frequencies

 * @dev: The struct device

 * @fw_link_freqs: Array of link frequencies from firmware

 * @num_of_fw_link_freqs: Number of entries in @fw_link_freqs

 * @driver_link_freqs: Array of link frequencies supported by the driver

 * @num_of_driver_link_freqs: Number of entries in @driver_link_freqs

 * @bitmap: Bitmap of driver-supported link frequencies found in @fw_link_freqs

 *

 * This function checks which driver-supported link frequencies are enabled in

 * system firmware and sets the corresponding bits in @bitmap (after first

 * zeroing it).

 *

 * Return values:

 *	0: Success

 *	-ENOENT: No match found between driver-supported link frequencies and

 *		 those available in firmware.

 *	-ENODATA: No link frequencies were specified in firmware.

 */

int v4l2_link_freq_to_bitmap(struct device *dev, const u64 *fw_link_freqs,

			     unsigned int num_of_fw_link_freqs,

			     const s64 *driver_link_freqs,

			     unsigned int num_of_driver_link_freqs,

			     unsigned long *bitmap);



static inline u64 v4l2_buffer_get_timestamp(const struct v4l2_buffer *buf)

{

	/*