dpll: zl3073x: Include current frequency in supported frequencies list

Ensure the current pin frequency is always present in the list of
supported frequencies reported to userspace. Previously, if the
firmware node was missing or didn't include the current operating
frequency in the supported-frequencies-hz property, the pin would
report a frequency that wasn't in its supported list.

Get the current frequency early in zl3073x_pin_props_get():
- For input pins: use zl3073x_dev_ref_freq_get()
- For output pins: use zl3073x_dev_output_pin_freq_get()

Place the current frequency at index 0 of the supported frequencies
array, then append frequencies from the firmware node (if present),
skipping any duplicate of the current frequency.

Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Link: https://patch.msgid.link/20260205154350.3180465-3-ivecera@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: ivecera

drivers/dpll/zl3073x/prop.c

@@ -193,9 +193,10 @@ struct zl3073x_pin_props *zl3073x_pin_props_get(struct zl3073x_dev *zldev,
 {
 	struct dpll_pin_frequency *ranges;
 	struct zl3073x_pin_props *props;
-	int i, j, num_freqs, rc;
+	int i, j, num_freqs = 0, rc;
+	u64 *freqs = NULL;
 	const char *type;
-	u64 *freqs;
+	u32 curr_freq;
 
 	props = kzalloc(sizeof(*props), GFP_KERNEL);
 	if (!props)
@@ -207,6 +208,7 @@ struct zl3073x_pin_props *zl3073x_pin_props_get(struct zl3073x_dev *zldev,
 		props->dpll_props.capabilities =
 			DPLL_PIN_CAPABILITIES_PRIORITY_CAN_CHANGE |
 			DPLL_PIN_CAPABILITIES_STATE_CAN_CHANGE;
+		curr_freq = zl3073x_dev_ref_freq_get(zldev, index);
 	} else {
 		u8 out, synth;
 		u32 f;
@@ -220,6 +222,7 @@ struct zl3073x_pin_props *zl3073x_pin_props_get(struct zl3073x_dev *zldev,
 		synth = zl3073x_dev_out_synth_get(zldev, out);
 		f = 2 * zl3073x_dev_synth_freq_get(zldev, synth);
 		props->dpll_props.phase_gran = f ? div_u64(PSEC_PER_SEC, f) : 1;
+		curr_freq = zl3073x_dev_output_pin_freq_get(zldev, index);
 	}
 
 	props->dpll_props.phase_range.min = S32_MIN;
@@ -230,7 +233,7 @@ struct zl3073x_pin_props *zl3073x_pin_props_get(struct zl3073x_dev *zldev,
 	/* Get firmware node for the given pin */
 	rc = zl3073x_prop_pin_fwnode_get(zldev, props, dir, index);
 	if (rc)
-		return props; /* Return if it does not exist */
+		goto skip_fwnode_props;
 
 	/* Look for label property and store the value as board label */
 	fwnode_property_read_string(props->fwnode, "label",
@@ -264,9 +267,10 @@ struct zl3073x_pin_props *zl3073x_pin_props_get(struct zl3073x_dev *zldev,
 	/* Read supported frequencies property if it is specified */
 	num_freqs = fwnode_property_count_u64(props->fwnode,
 					      "supported-frequencies-hz");
-	if (num_freqs <= 0)
-		/* Return if the property does not exist or number is 0 */
-		return props;
+	if (num_freqs <= 0) {
+		num_freqs = 0;
+		goto skip_fwnode_props;
+	}
 
 	/* The firmware node specifies list of supported frequencies while
 	 * DPLL core pin properties requires list of frequency ranges.
@@ -283,19 +287,25 @@ struct zl3073x_pin_props *zl3073x_pin_props_get(struct zl3073x_dev *zldev,
 				       "supported-frequencies-hz", freqs,
 				       num_freqs);
 
-	/* Allocate frequency ranges list and fill it */
-	ranges = kcalloc(num_freqs, sizeof(*ranges), GFP_KERNEL);
+skip_fwnode_props:
+	/* Allocate frequency ranges list - extra slot for current frequency */
+	ranges = kcalloc(num_freqs + 1, sizeof(*ranges), GFP_KERNEL);
 	if (!ranges) {
 		rc = -ENOMEM;
 		goto err_alloc_ranges;
 	}
 
-	/* Convert list of frequencies to list of frequency ranges but
-	 * filter-out frequencies that are not representable by device
+	/* Start with current frequency at index 0 */
+	ranges[0] = (struct dpll_pin_frequency)DPLL_PIN_FREQUENCY(curr_freq);
+
+	/* Add frequencies from firmware node, skipping current frequency
+	 * and filtering out frequencies not representable by device
 	 */
-	for (i = 0, j = 0; i < num_freqs; i++) {
+	for (i = 0, j = 1; i < num_freqs; i++) {
 		struct dpll_pin_frequency freq = DPLL_PIN_FREQUENCY(freqs[i]);
 
+		if (freqs[i] == curr_freq)
+			continue;
 		if (zl3073x_pin_check_freq(zldev, dir, index, freqs[i])) {
 			ranges[j] = freq;
 			j++;