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From 3c9862ba40f621a5922e755ba36f817ed1be2f5a Mon Sep 17 00:00:00 2001
From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Sat, 3 Jul 2021 12:44:57 +0300
Subject: drm/amdgpu: Fix signedness bug in __amdgpu_eeprom_xfer()
Git-commit: 1d864f1088bbcf7f6ffa83053dcc8684a1a436cb
Patch-mainline: v5.15-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225

The i2c_transfer() function returns negatives or else the number of
messages transferred.  This code does not work because ARRAY_SIZE()
is type size_t and so that means negative values of "r" are type
promoted to high positive values which are greater than the ARRAY_SIZE().

Fix this by changing the < to != which works regardless of type
promotion.

Fixes: 746b584762e452 ("drm/amdgpu: Fixes to the AMDGPU EEPROM driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Luben Tuikov <luben.tuikov@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_eeprom.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_eeprom.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_eeprom.c
index 4c3c65a5acae..4d9eb0137f8c 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_eeprom.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_eeprom.c
@@ -147,7 +147,7 @@ static int __amdgpu_eeprom_xfer(struct i2c_adapter *i2c_adap, u32 eeprom_addr,
 		/* This constitutes a START-STOP transaction.
 		 */
 		r = i2c_transfer(i2c_adap, msgs, ARRAY_SIZE(msgs));
-		if (r < ARRAY_SIZE(msgs))
+		if (r != ARRAY_SIZE(msgs))
 			break;
 
 		if (!read) {
-- 
2.38.1