[PATCH 2/2] hwmon: pmbus: adm1275: add adm1281 support

[Jose Ramon San Buenaventura <jose.sanbuenaventura@analog.com>]

Adding support for adm1281 which is similar to adm1275

ADM1281 has STATUS_CML read support which is also being added.

Signed-off-by: Jose Ramon San Buenaventura <jose.sanbuenaventura@analog.com>
---
 Documentation/hwmon/adm1275.rst | 14 +++++++++++---
 drivers/hwmon/pmbus/Kconfig     |  4 ++--
 drivers/hwmon/pmbus/adm1275.c   | 27 +++++++++++++++++++++++++--
 3 files changed, 38 insertions(+), 7 deletions(-)

diff --git a/Documentation/hwmon/adm1275.rst b/Documentation/hwmon/adm1275.rst
index 804590eea..467daf8ce 100644
--- a/Documentation/hwmon/adm1275.rst
+++ b/Documentation/hwmon/adm1275.rst
@@ -43,6 +43,14 @@ Supported chips:
 
     Datasheet: www.analog.com/static/imported-files/data_sheets/ADM1278.pdf
 
+  * Analog Devices ADM1281
+
+    Prefix: 'adm1281'
+
+    Addresses scanned: -
+
+    Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/adm1281.pdf
+
   * Analog Devices ADM1293/ADM1294
 
     Prefix: 'adm1293', 'adm1294'
@@ -58,10 +66,10 @@ Description
 -----------
 
 This driver supports hardware monitoring for Analog Devices ADM1075, ADM1272,
-ADM1275, ADM1276, ADM1278, ADM1293, and ADM1294 Hot-Swap Controller and
+ADM1275, ADM1276, ADM1278, ADM1281, ADM1293, and ADM1294 Hot-Swap Controller and
 Digital Power Monitors.
 
-ADM1075, ADM1272, ADM1275, ADM1276, ADM1278, ADM1293, and ADM1294 are hot-swap
+ADM1075, ADM1272, ADM1275, ADM1276, ADM1278, ADM1281, ADM1293, and ADM1294 are hot-swap
 controllers that allow a circuit board to be removed from or inserted into
 a live backplane. They also feature current and voltage readback via an
 integrated 12 bit analog-to-digital converter (ADC), accessed using a
@@ -144,5 +152,5 @@ temp1_highest		Highest observed temperature.
 temp1_reset_history	Write any value to reset history.
 
 			Temperature attributes are supported on ADM1272 and
-			ADM1278.
+			ADM1278, and ADM1281.
 ======================= =======================================================
diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
index 557ae0c41..9c1d0d7d5 100644
--- a/drivers/hwmon/pmbus/Kconfig
+++ b/drivers/hwmon/pmbus/Kconfig
@@ -51,8 +51,8 @@ config SENSORS_ADM1275
 	tristate "Analog Devices ADM1275 and compatibles"
 	help
 	  If you say yes here you get hardware monitoring support for Analog
-	  Devices ADM1075, ADM1272, ADM1275, ADM1276, ADM1278, ADM1293,
-	  and ADM1294 Hot-Swap Controller and Digital Power Monitors.
+	  Devices ADM1075, ADM1272, ADM1275, ADM1276, ADM1278, ADM1281,
+	  ADM1293, and ADM1294 Hot-Swap Controller and Digital Power Monitors.
 
 	  This driver can also be built as a module. If so, the module will
 	  be called adm1275.
diff --git a/drivers/hwmon/pmbus/adm1275.c b/drivers/hwmon/pmbus/adm1275.c
index e2c61d6fa..6c3e8840f 100644
--- a/drivers/hwmon/pmbus/adm1275.c
+++ b/drivers/hwmon/pmbus/adm1275.c
@@ -18,7 +18,7 @@
 #include <linux/log2.h>
 #include "pmbus.h"
 
-enum chips { adm1075, adm1272, adm1275, adm1276, adm1278, adm1293, adm1294 };
+enum chips { adm1075, adm1272, adm1275, adm1276, adm1278, adm1281, adm1293, adm1294 };
 
 #define ADM1275_MFR_STATUS_IOUT_WARN2	BIT(0)
 #define ADM1293_MFR_STATUS_VAUX_UV_WARN	BIT(5)
@@ -101,6 +101,7 @@ struct adm1275_data {
 	bool have_pin_max;
 	bool have_temp_max;
 	bool have_power_sampling;
+	bool have_status_cml;
 	struct pmbus_driver_info info;
 };
 
@@ -469,6 +470,22 @@ static int adm1275_read_byte_data(struct i2c_client *client, int page, int reg)
 				ret |= PB_VOLTAGE_UV_WARNING;
 		}
 		break;
+	case PMBUS_STATUS_CML:
+		if (!data->have_status_cml)
+			return -ENXIO;
+
+		ret = pmbus_read_byte_data(client, page, PMBUS_STATUS_BYTE);
+		if (ret < 0)
+			break;
+
+		if (ret & PB_STATUS_CML) {
+			ret = pmbus_read_byte_data(client, page, PMBUS_STATUS_CML);
+			if (ret < 0)
+				break;
+		} else {
+			ret = 0;
+		}
+		break;
 	default:
 		ret = -ENODATA;
 		break;
@@ -482,6 +499,7 @@ static const struct i2c_device_id adm1275_id[] = {
 	{ "adm1275", adm1275 },
 	{ "adm1276", adm1276 },
 	{ "adm1278", adm1278 },
+	{ "adm1281", adm1281 },
 	{ "adm1293", adm1293 },
 	{ "adm1294", adm1294 },
 	{ }
@@ -555,7 +573,8 @@ static int adm1275_probe(struct i2c_client *client)
 			   client->name, mid->name);
 
 	if (mid->driver_data == adm1272 || mid->driver_data == adm1278 ||
-	    mid->driver_data == adm1293 || mid->driver_data == adm1294)
+	    mid->driver_data == adm1281 || mid->driver_data == adm1293 ||
+	    mid->driver_data == adm1294)
 		config_read_fn = i2c_smbus_read_word_data;
 	else
 		config_read_fn = i2c_smbus_read_byte_data;
@@ -703,6 +722,10 @@ static int adm1275_probe(struct i2c_client *client)
 			  PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT;
 		break;
 	case adm1278:
+	case adm1281:
+		if (data->id == adm1281)
+			data->have_status_cml = true;
+
 		data->have_vout = true;
 		data->have_pin_max = true;
 		data->have_temp_max = true;
-- 
2.39.2