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Sender: Guenter Roeck <groeck7@gmail.com>
From:   Guenter Roeck <linux@roeck-us.net>
To:     linux-hwmon@vger.kernel.org
Cc:     linux-kernel@vger.kernel.org, Jean Delvare <jdelvare@suse.com>,
        Slawomir Stepien <sst@poczta.fm>,
        Guenter Roeck <linux@roeck-us.net>
Subject: [PATCH 09/40] hwmon: (lm90) Add partial PEC support for ADT7461
Date:   Wed, 25 May 2022 06:57:27 -0700
Message-Id: <20220525135758.2944744-10-linux@roeck-us.net>
In-Reply-To: <20220525135758.2944744-1-linux@roeck-us.net>
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Revision 0 of the ADT7461 datasheet suggests that the chip supports PEC
(packet error checking). This information is gone in later versions of the
datasheet. Experiments show that PEC support on ADT7461 is similar to PEC
support in ADM1032, ie it is only supported for read operations. Add
support for it to the driver.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
 Documentation/hwmon/lm90.rst | 1 +
 drivers/hwmon/lm90.c         | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/Documentation/hwmon/lm90.rst b/Documentation/hwmon/lm90.rst
index f107d4a159fa..9886a298797f 100644
--- a/Documentation/hwmon/lm90.rst
+++ b/Documentation/hwmon/lm90.rst
@@ -322,6 +322,7 @@ ADM1032:
 ADT7461, ADT7461A, NCT1008:
   * Extended temperature range (breaks compatibility)
   * Lower resolution for remote temperature
+  * SMBus PEC support for Write Byte and Receive Byte transactions.
 
 MAX6654:
   * Better local resolution
diff --git a/drivers/hwmon/lm90.c b/drivers/hwmon/lm90.c
index 8ba95ea06f0c..6c79422da420 100644
--- a/drivers/hwmon/lm90.c
+++ b/drivers/hwmon/lm90.c
@@ -356,7 +356,7 @@ static const struct lm90_params lm90_params[] = {
 	[adt7461] = {
 		.flags = LM90_HAVE_OFFSET | LM90_HAVE_REM_LIMIT_EXT
 		  | LM90_HAVE_BROKEN_ALERT | LM90_HAVE_EXTENDED_TEMP
-		  | LM90_HAVE_CRIT,
+		  | LM90_HAVE_CRIT | LM90_HAVE_PARTIAL_PEC,
 		.alert_alarms = 0x7c,
 		.max_convrate = 10,
 	},
-- 
2.35.1