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@xxxxxxxxxxxxxxx>
---
drivers/media/v4l2-core/v4l2-common.c | 47 +++++++++++++++++++++++++++
include/media/v4l2-common.h | 25 ++++++++++++++
2 files changed, 72 insertions(+)
diff --git a/drivers/media/v4l2-core/v4l2-common.c b/drivers/media/v4l2-core/v4l2-common.c
index 273d83de2a87..d34d210908d9 100644
--- a/drivers/media/v4l2-core/v4l2-common.c
+++ b/drivers/media/v4l2-core/v4l2-common.c
@@ -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);
diff --git a/include/media/v4l2-common.h b/include/media/v4l2-common.h
index acf5be24a5ca..cd2163f24f8a 100644
--- a/include/media/v4l2-common.h
+++ b/include/media/v4l2-common.h
@@ -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)
{
/*
--
2.39.2
