From 883086c7a059c3391b4573f63e1a54d1f58e949e Mon Sep 17 00:00:00 2001
From: Kyle Keen <keenerd@gmail.com>
Date: Mon, 11 Aug 2014 15:54:48 -0400
Subject: [PATCH] lib: retry i2c on failure

---
 src/librtlsdr.c | 28 ++++++++++++++++++++++------
 1 file changed, 22 insertions(+), 6 deletions(-)

diff --git a/src/librtlsdr.c b/src/librtlsdr.c
index 1a2573e..a3b5359 100644
--- a/src/librtlsdr.c
+++ b/src/librtlsdr.c
@@ -1950,16 +1950,32 @@ uint32_t rtlsdr_get_tuner_clock(void *dev)
 
 int rtlsdr_i2c_write_fn(void *dev, uint8_t addr, uint8_t *buf, int len)
 {
-	if (dev)
-		return rtlsdr_i2c_write(((rtlsdr_dev_t *)dev), addr, buf, len);
-
+	int r;
+	int retries = 2;
+	if (!dev)
+		return -1;
+	do {
+		r = rtlsdr_i2c_write(((rtlsdr_dev_t *)dev), addr, buf, len);
+		if (r >= 0)
+		    return r;
+		rtlsdr_set_i2c_repeater(dev, 2);
+		retries--;
+	} while (retries > 0);
 	return -1;
 }
 
 int rtlsdr_i2c_read_fn(void *dev, uint8_t addr, uint8_t *buf, int len)
 {
-	if (dev)
-		return rtlsdr_i2c_read(((rtlsdr_dev_t *)dev), addr, buf, len);
-
+	int r;
+	int retries = 2;
+	if (!dev)
+		return -1;
+	do {
+		r = rtlsdr_i2c_read(((rtlsdr_dev_t *)dev), addr, buf, len);
+		if (r >= 0)
+		    return r;
+		rtlsdr_set_i2c_repeater(dev, 2);
+		retries--;
+	} while (retries > 0);
 	return -1;
 }