diff mbox series

[1/4] media: v4l: Add a helper for setting up link-frequencies control

Message ID 20231211140658.366268-2-sakari.ailus@linux.intel.com
State Accepted
Commit a68e88e2cf9e4f3bec1783d686beb2439f4a26e0
Headers show
Series [1/4] media: v4l: Add a helper for setting up link-frequencies control | expand

Commit Message

Sakari Ailus Dec. 11, 2023, 2:06 p.m. UTC
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: Sakari Ailus <sakari.ailus@linux.intel.com>
---
 drivers/media/v4l2-core/v4l2-common.c | 48 +++++++++++++++++++++++++++
 include/media/v4l2-common.h           | 27 +++++++++++++++
 2 files changed, 75 insertions(+)

Comments

kernel test robot Dec. 12, 2023, 4:07 p.m. UTC | #1
Hi Sakari,

kernel test robot noticed the following build warnings:

[auto build test WARNING on media-tree/master]
[also build test WARNING on linuxtv-media-stage/master sailus-media-tree/streams linus/master v6.7-rc5 next-20231212]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Sakari-Ailus/media-v4l-Add-a-helper-for-setting-up-link-frequencies-control/20231211-220844
base:   git://linuxtv.org/media_tree.git master
patch link:    https://lore.kernel.org/r/20231211140658.366268-2-sakari.ailus%40linux.intel.com
patch subject: [PATCH 1/4] media: v4l: Add a helper for setting up link-frequencies control
reproduce: (https://download.01.org/0day-ci/archive/20231212/202312122344.1l0j6bV6-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202312122344.1l0j6bV6-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> Documentation/driver-api/media/v4l2-common:6: ./include/media/v4l2-common.h:567: WARNING: Unexpected indentation.
>> Documentation/driver-api/media/v4l2-common:6: ./include/media/v4l2-common.h:568: WARNING: Block quote ends without a blank line; unexpected unindent.
diff mbox series

Patch

diff --git a/drivers/media/v4l2-core/v4l2-common.c b/drivers/media/v4l2-core/v4l2-common.c
index e9e7e70fa24e..63302009db5f 100644
--- a/drivers/media/v4l2-core/v4l2-common.c
+++ b/drivers/media/v4l2-core/v4l2-common.c
@@ -585,3 +585,51 @@  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_frequencies_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_frequencies_to_bitmap);
diff --git a/include/media/v4l2-common.h b/include/media/v4l2-common.h
index d278836fd9cb..adf997baf659 100644
--- a/include/media/v4l2-common.h
+++ b/include/media/v4l2-common.h
@@ -547,6 +547,33 @@  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_frequencies_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_frequencies_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)
 {
 	/*