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, 27 insertions, 0 deletions

diff --git a/include/net/pptp.h b/include/net/pptp.h
new file mode 100644
index 000000000..e63176bdd
--- /dev/null
+++ b/include/net/pptp.h
@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _NET_PPTP_H
+#define _NET_PPTP_H
+
+#include <linux/types.h>
+#include <net/gre.h>
+
+#define PPP_LCP_ECHOREQ 0x09
+#define PPP_LCP_ECHOREP 0x0A
+#define SC_RCV_BITS     (SC_RCV_B7_1|SC_RCV_B7_0|SC_RCV_ODDP|SC_RCV_EVNP)
+
+#define MISSING_WINDOW 20
+#define WRAPPED(curseq, lastseq)\
+	((((curseq) & 0xffffff00) == 0) &&\
+	(((lastseq) & 0xffffff00) == 0xffffff00))
+
+#define PPTP_HEADER_OVERHEAD (2+sizeof(struct pptp_gre_header))
+struct pptp_gre_header {
+	struct gre_base_hdr gre_hd;
+	__be16 payload_len;
+	__be16 call_id;
+	__be32 seq;
+	__be32 ack;
+} __packed;
+
+
+#endif