i2c: Bus drivers return -Errno not -1

Tighten error paths used by various i2c adapters (mostly x86) so
they return real fault/errno codes instead of a "-1" (which is
most often interpreted as "-EPERM").  Build tested, with eyeball
review.

One minor initial goal is to have adapters consistently return
the code "-ENXIO" when addressing a device doesn't get an ACK
response, at least in the probe paths where they are already
good at stifling related logspam.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/i2c/busses/i2c-amd756-s4882.c b/drivers/i2c/busses/i2c-amd756-s4882.c
index c38a0a112208..2f150e33c74c 100644
--- a/drivers/i2c/busses/i2c-amd756-s4882.c
+++ b/drivers/i2c/busses/i2c-amd756-s4882.c
@@ -58,7 +58,7 @@ static s32 amd756_access_virt0(struct i2c_adapter * adap, u16 addr,
         /* We exclude the multiplexed addresses */
         if (addr == 0x4c || (addr & 0xfc) == 0x50 || (addr & 0xfc) == 0x30
          || addr == 0x18)
-                return -1;
+                return -ENXIO;
 
         mutex_lock(&amd756_lock);
 
@@ -86,7 +86,7 @@ static inline s32 amd756_access_channel(struct i2c_adapter * adap, u16 addr,
 
         /* We exclude the non-multiplexed addresses */
         if (addr != 0x4c && (addr & 0xfc) != 0x50 && (addr & 0xfc) != 0x30)
-                return -1;
+                return -ENXIO;
 
         mutex_lock(&amd756_lock);