[PATCH 5.4 42/47] hwmom: (lm90) Fix citical alarm status for MAX6680/MAX6681 - Greg Kroah-Hartman

From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	stable@vger.kernel.org, Guenter Roeck <linux@roeck-us.net>
Subject: [PATCH 5.4 42/47] hwmom: (lm90) Fix citical alarm status for MAX6680/MAX6681
Date: Mon, 27 Dec 2021 16:31:18 +0100	[thread overview]
Message-ID: <20211227151322.259734116@linuxfoundation.org> (raw)
In-Reply-To: <20211227151320.801714429@linuxfoundation.org>

From: Guenter Roeck <linux@roeck-us.net>

commit da7dc0568491104c7acb632e9d41ddce9aaabbb1 upstream.

Tests with a real chip and a closer look into the datasheet reveals
that the local and remote critical alarm status bits are swapped for
MAX6680/MAX6681.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/hwmon/lm90.c |   10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

--- a/drivers/hwmon/lm90.c
+++ b/drivers/hwmon/lm90.c
@@ -190,6 +190,7 @@ enum chips { lm90, adm1032, lm99, lm86,
 #define LM90_HAVE_EXTENDED_TEMP	(1 << 8) /* extended temperature support*/
 #define LM90_PAUSE_FOR_CONFIG	(1 << 9) /* Pause conversion for config	*/
 #define LM90_HAVE_CRIT		(1 << 10)/* Chip supports CRIT/OVERT register	*/
+#define LM90_HAVE_CRIT_ALRM_SWP	(1 << 11)/* critical alarm bits swapped	*/
 
 /* LM90 status */
 #define LM90_STATUS_LTHRM	(1 << 0) /* local THERM limit tripped */
@@ -415,7 +416,8 @@ static const struct lm90_params lm90_par
 		.reg_local_ext = MAX6657_REG_R_LOCAL_TEMPL,
 	},
 	[max6680] = {
-		.flags = LM90_HAVE_OFFSET | LM90_HAVE_CRIT,
+		.flags = LM90_HAVE_OFFSET | LM90_HAVE_CRIT
+		  | LM90_HAVE_CRIT_ALRM_SWP,
 		.alert_alarms = 0x7c,
 		.max_convrate = 7,
 	},
@@ -1191,6 +1193,7 @@ static const u8 lm90_temp_emerg_index[3]
 static const u8 lm90_min_alarm_bits[3] = { 5, 3, 11 };
 static const u8 lm90_max_alarm_bits[3] = { 6, 4, 12 };
 static const u8 lm90_crit_alarm_bits[3] = { 0, 1, 9 };
+static const u8 lm90_crit_alarm_bits_swapped[3] = { 1, 0, 9 };
 static const u8 lm90_emergency_alarm_bits[3] = { 15, 13, 14 };
 static const u8 lm90_fault_bits[3] = { 0, 2, 10 };
 
@@ -1216,7 +1219,10 @@ static int lm90_temp_read(struct device
 		*val = (data->alarms >> lm90_max_alarm_bits[channel]) & 1;
 		break;
 	case hwmon_temp_crit_alarm:
-		*val = (data->alarms >> lm90_crit_alarm_bits[channel]) & 1;
+		if (data->flags & LM90_HAVE_CRIT_ALRM_SWP)
+			*val = (data->alarms >> lm90_crit_alarm_bits_swapped[channel]) & 1;
+		else
+			*val = (data->alarms >> lm90_crit_alarm_bits[channel]) & 1;
 		break;
 	case hwmon_temp_emergency_alarm:
 		*val = (data->alarms >> lm90_emergency_alarm_bits[channel]) & 1;


