[2/3] iio: gts: split table-building function

Commit Message

Matti Vaittinen Nov. 28, 2024, 4:50 p.m. UTC

The function which builds the available scales tables for the GTS
helpers is hard to follow. Split it up so it is more obvious for
occasional reader to see what is done and why.

Signed-off-by: Matti Vaittinen <[e-mail]>
---
 drivers/iio/industrialio-gts-helper.c | 66 +++++++++++++++++----------
 1 file changed, 42 insertions(+), 24 deletions(-)

Patch

diff --git a/drivers/iio/industrialio-gts-helper.c b/drivers/iio/industrialio-gts-helper.c
index e15d0112e9e3..7f900f578f1d 100644
--- a/drivers/iio/industrialio-gts-helper.c
+++ b/drivers/iio/industrialio-gts-helper.c
@@ -191,14 +191,10 @@  static int fill_and_sort_scaletables(struct iio_gts *gts, int **gains, int **sca
 	return 0;
 }
 
-static int build_combined_table(struct iio_gts *gts, int **gains, size_t gain_bytes)
+static int combine_gain_tables(struct iio_gts *gts, int **gains,
+			       int *all_gains, size_t gain_bytes)
 {
-	int ret, i, j, new_idx, time_idx;
-	int *all_gains __free(kfree) = kcalloc(gts->num_itime, gain_bytes,
-					       GFP_KERNEL);
-
-	if (!all_gains)
-		return -ENOMEM;
+	int i, new_idx, time_idx;
 
 	/*
 	 * We assume all the gains for same integration time were unique.
@@ -212,8 +208,8 @@  static int build_combined_table(struct iio_gts *gts, int **gains, size_t gain_by
 	new_idx = gts->num_hwgain;
 
 	while (time_idx-- > 0) {
-		for (j = 0; j < gts->num_hwgain; j++) {
-			int candidate = gains[time_idx][j];
+		for (i = 0; i < gts->num_hwgain; i++) {
+			int candidate = gains[time_idx][i];
 			int chk;
 
 			if (candidate > all_gains[new_idx - 1]) {
@@ -236,25 +232,47 @@  static int build_combined_table(struct iio_gts *gts, int **gains, size_t gain_by
 		}
 	}
 
-	gts->avail_all_scales_table = kcalloc(new_idx, 2 * sizeof(int),
-					      GFP_KERNEL);
-	if (!gts->avail_all_scales_table)
-		return -ENOMEM;
+	return new_idx;
+}
 
-	gts->num_avail_all_scales = new_idx;
+static int *build_all_scales_table(struct iio_gts *gts, int *all_gains, int num_scales)
+{
+	int i, ret;
+	int *all_scales __free(kfree) = kcalloc(num_scales, 2 * sizeof(int),
+						GFP_KERNEL);
 
-	for (i = 0; i < gts->num_avail_all_scales; i++) {
-		ret = iio_gts_total_gain_to_scale(gts, all_gains[i],
-					&gts->avail_all_scales_table[i * 2],
-					&gts->avail_all_scales_table[i * 2 + 1]);
+	if (!all_scales)
+		return ERR_PTR(-ENOMEM);
 
-		if (ret) {
-			kfree(gts->avail_all_scales_table);
-			gts->num_avail_all_scales = 0;
-			return ret;
-		}
+	for (i = 0; i < num_scales; i++) {
+		ret = iio_gts_total_gain_to_scale(gts, all_gains[i], &all_scales[i * 2],
+						  &all_scales[i * 2 + 1]);
+		if (ret)
+			return ERR_PTR(ret);
 	}
 
+	return_ptr(all_scales);
+}
+
+static int build_combined_tables(struct iio_gts *gts,
+				 int **gains, size_t gain_bytes)
+{
+	int *all_scales, num_gains;
+	int *all_gains __free(kfree) = kcalloc(gts->num_itime, gain_bytes,
+					       GFP_KERNEL);
+
+	if (!all_gains)
+		return -ENOMEM;
+
+	num_gains = combine_gain_tables(gts, gains, all_gains, gain_bytes);
+
+	all_scales = build_all_scales_table(gts, all_gains, num_gains);
+	if (IS_ERR(all_scales))
+		return PTR_ERR(all_scales);
+
+	gts->num_avail_all_scales = num_gains;
+	gts->avail_all_scales_table = all_scales;
+
 	return 0;
 }
 
@@ -269,7 +287,7 @@  static int gain_to_scaletables(struct iio_gts *gts, int **gains, int **scales)
 
 	gain_bytes = array_size(gts->num_hwgain, sizeof(int));
 
-	return build_combined_table(gts, gains, gain_bytes);
+	return build_combined_tables(gts, gains, gain_bytes);
 }
 
 /**