iio: proximity: isl29501: Fix return type of isl29501_register_writegrafted

isl29501_register_write() was returning a u32 instead of an int.
Since the function returns negative error codes (such as -ERANGE or
return values from i2c_smbus_write_byte_data()), returning an unsigned
integer type prevents callers from correctly checking for negative error
conditions.

Fix this by changing the function return type from u32 to int.

This was found through manual code review.

Fixes: 1c28799257bc ("iio: light: isl29501: Add support for the ISL29501 ToF sensor.")
Signed-off-by: Salah Triki <salah.triki@gmail.com>
Reviewed-by: Joshua Crofts <joshua.crofts1@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jonathan Cameron <jonathan.cameron@oss.qualcomm.com>

1 files changed, 157 insertions, 0 deletions

diff --git a/lib/raid/raid6/mktables.c b/lib/raid/raid6/mktables.c
new file mode 100644
index 000000000..b6327b562
--- /dev/null
+++ b/lib/raid/raid6/mktables.c
@@ -0,0 +1,157 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright 2002-2007 H. Peter Anvin - All Rights Reserved
+ *
+ * Make RAID-6 tables.  This is a host user space program to be run at compile
+ * time.
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <inttypes.h>
+#include <stdlib.h>
+#include <time.h>
+
+static uint8_t gfmul(uint8_t a, uint8_t b)
+{
+	uint8_t v = 0;
+
+	while (b) {
+		if (b & 1)
+			v ^= a;
+		a = (a << 1) ^ (a & 0x80 ? 0x1d : 0);
+		b >>= 1;
+	}
+
+	return v;
+}
+
+static uint8_t gfpow(uint8_t a, int b)
+{
+	uint8_t v = 1;
+
+	b %= 255;
+	if (b < 0)
+		b += 255;
+
+	while (b) {
+		if (b & 1)
+			v = gfmul(v, a);
+		a = gfmul(a, a);
+		b >>= 1;
+	}
+
+	return v;
+}
+
+int main(int argc, char *argv[])
+{
+	int i, j, k;
+	uint8_t v;
+	uint8_t exptbl[256], invtbl[256];
+
+	printf("#include <linux/export.h>\n");
+	printf("#include \"algos.h\"\n");
+
+	/* Compute multiplication table */
+	printf("\nconst u8  __attribute__((aligned(256)))\n"
+		"raid6_gfmul[256][256] =\n"
+		"{\n");
+	for (i = 0; i < 256; i++) {
+		printf("\t{\n");
+		for (j = 0; j < 256; j += 8) {
+			printf("\t\t");
+			for (k = 0; k < 8; k++)
+				printf("0x%02x,%c", gfmul(i, j + k),
+				       (k == 7) ? '\n' : ' ');
+		}
+		printf("\t},\n");
+	}
+	printf("};\n");
+	printf("EXPORT_SYMBOL(raid6_gfmul);\n");
+
+	/* Compute vector multiplication table */
+	printf("\nconst u8  __attribute__((aligned(256)))\n"
+		"raid6_vgfmul[256][32] =\n"
+		"{\n");
+	for (i = 0; i < 256; i++) {
+		printf("\t{\n");
+		for (j = 0; j < 16; j += 8) {
+			printf("\t\t");
+			for (k = 0; k < 8; k++)
+				printf("0x%02x,%c", gfmul(i, j + k),
+				       (k == 7) ? '\n' : ' ');
+		}
+		for (j = 0; j < 16; j += 8) {
+			printf("\t\t");
+			for (k = 0; k < 8; k++)
+				printf("0x%02x,%c", gfmul(i, (j + k) << 4),
+				       (k == 7) ? '\n' : ' ');
+		}
+		printf("\t},\n");
+	}
+	printf("};\n");
+	printf("EXPORT_SYMBOL(raid6_vgfmul);\n");
+
+	/* Compute power-of-2 table (exponent) */
+	v = 1;
+	printf("\nconst u8 __attribute__((aligned(256)))\n"
+	       "raid6_gfexp[256] =\n" "{\n");
+	for (i = 0; i < 256; i += 8) {
+		printf("\t");
+		for (j = 0; j < 8; j++) {
+			exptbl[i + j] = v;
+			printf("0x%02x,%c", v, (j == 7) ? '\n' : ' ');
+			v = gfmul(v, 2);
+			if (v == 1)
+				v = 0;	/* For entry 255, not a real entry */
+		}
+	}
+	printf("};\n");
+	printf("EXPORT_SYMBOL(raid6_gfexp);\n");
+
+	/* Compute log-of-2 table */
+	printf("\nconst u8 __attribute__((aligned(256)))\n"
+	       "raid6_gflog[256] =\n" "{\n");
+	for (i = 0; i < 256; i += 8) {
+		printf("\t");
+		for (j = 0; j < 8; j++) {
+			v = 255;
+			for (k = 0; k < 256; k++)
+				if (exptbl[k] == (i + j)) {
+					v = k;
+					break;
+				}
+			printf("0x%02x,%c", v, (j == 7) ? '\n' : ' ');
+		}
+	}
+	printf("};\n");
+	printf("EXPORT_SYMBOL(raid6_gflog);\n");
+
+	/* Compute inverse table x^-1 == x^254 */
+	printf("\nconst u8 __attribute__((aligned(256)))\n"
+	       "raid6_gfinv[256] =\n" "{\n");
+	for (i = 0; i < 256; i += 8) {
+		printf("\t");
+		for (j = 0; j < 8; j++) {
+			invtbl[i + j] = v = gfpow(i + j, 254);
+			printf("0x%02x,%c", v, (j == 7) ? '\n' : ' ');
+		}
+	}
+	printf("};\n");
+	printf("EXPORT_SYMBOL(raid6_gfinv);\n");
+
+	/* Compute inv(2^x + 1) (exponent-xor-inverse) table */
+	printf("\nconst u8 __attribute__((aligned(256)))\n"
+	       "raid6_gfexi[256] =\n" "{\n");
+	for (i = 0; i < 256; i += 8) {
+		printf("\t");
+		for (j = 0; j < 8; j++)
+			printf("0x%02x,%c", invtbl[exptbl[i + j] ^ 1],
+			       (j == 7) ? '\n' : ' ');
+	}
+	printf("};\n");
+	printf("EXPORT_SYMBOL(raid6_gfexi);\n");
+
+	return 0;
+}