From be8a1f7cd4501c3b4b32543577a33aee6d2193ac Mon Sep 17 00:00:00 2001 From: Olof Johansson Date: Thu, 15 Nov 2007 19:24:02 +0100 Subject: [PATCH] i2c-pasemi: Fix NACK detection Turns out we don't actually check the status to see if there was a device out there to talk to, just if we had a timeout when doing so. Add the proper check, so we don't falsly think there are devices on the bus that are not there, etc. Signed-off-by: Olof Johansson Signed-off-by: Jean Delvare --- drivers/i2c/busses/i2c-pasemi.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/i2c/busses/i2c-pasemi.c b/drivers/i2c/busses/i2c-pasemi.c index 79c72dfa63b..ca18e0be490 100644 --- a/drivers/i2c/busses/i2c-pasemi.c +++ b/drivers/i2c/busses/i2c-pasemi.c @@ -51,6 +51,7 @@ struct pasemi_smbus { #define MRXFIFO_DATA_M 0x000000ff #define SMSTA_XEN 0x08000000 +#define SMSTA_MTN 0x00200000 #define CTL_MRR 0x00000400 #define CTL_MTR 0x00000200 @@ -98,6 +99,10 @@ static unsigned int pasemi_smb_waitready(struct pasemi_smbus *smbus) status = reg_read(smbus, REG_SMSTA); } + /* Got NACK? */ + if (status & SMSTA_MTN) + return -ENXIO; + if (timeout < 0) { dev_warn(&smbus->dev->dev, "Timeout, status 0x%08x\n", status); reg_write(smbus, REG_SMSTA, status); -- 2.41.0