[PATCH v2 2/2] hwmon: (pmbus/tda38740) Add driver for Infineon TDA38740/TDA38725

[Colin Huang]

From: Colin Huang <u8813345@xxxxxxxxx>

Add a PMBus driver for Infineon TDA38740 and TDA38725
single-voltage synchronous buck regulators.

Signed-off-by: Colin Huang <u8813345@xxxxxxxxx>
---
 drivers/hwmon/pmbus/Kconfig    |  9 ++++
 drivers/hwmon/pmbus/Makefile   |  1 +
 drivers/hwmon/pmbus/tda38740.c | 98 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 108 insertions(+)

diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
index bcfdc4ce4c10..e4ca80dd0574 100644
--- a/drivers/hwmon/pmbus/Kconfig
+++ b/drivers/hwmon/pmbus/Kconfig
@@ -763,6 +763,15 @@ config SENSORS_TDA38640_REGULATOR
 	  If you say yes here you get regulator support for Infineon
 	  TDA38640 as regulator.
 
+config SENSORS_TDA38740
+	tristate "Infineon TDA38725/TDA38740"
+	help
+	  If you say yes here you get hardware monitoring support for Infineon
+	  TDA38725 and TDA38740.
+
+	  This driver can also be built as a module. If so, the module will
+	  be called tda38740.
+
 config SENSORS_TPS25990
 	tristate "TI TPS25990"
 	help
diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
index e288fe72a437..eb06d47816fd 100644
--- a/drivers/hwmon/pmbus/Makefile
+++ b/drivers/hwmon/pmbus/Makefile
@@ -70,6 +70,7 @@ obj-$(CONFIG_SENSORS_STEF48H28)	+= stef48h28.o
 obj-$(CONFIG_SENSORS_SQ24860)	+= sq24860.o
 obj-$(CONFIG_SENSORS_STPDDC60)	+= stpddc60.o
 obj-$(CONFIG_SENSORS_TDA38640)	+= tda38640.o
+obj-$(CONFIG_SENSORS_TDA38740)	+= tda38740.o
 obj-$(CONFIG_SENSORS_TPS25990)	+= tps25990.o
 obj-$(CONFIG_SENSORS_TPS40422)	+= tps40422.o
 obj-$(CONFIG_SENSORS_TPS53679)	+= tps53679.o
diff --git a/drivers/hwmon/pmbus/tda38740.c b/drivers/hwmon/pmbus/tda38740.c
new file mode 100644
index 000000000000..4cf9a81b276c
--- /dev/null
+++ b/drivers/hwmon/pmbus/tda38740.c
@@ -0,0 +1,98 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Hardware monitoring driver for Infineon TDA38725/TDA38740
+ *
+ * Copyright (c) 2023 9elements GmbH
+ *
+ */
+
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include "pmbus.h"
+
+struct tda38740_data {
+	struct pmbus_driver_info info;
+};
+
+/*
+ * TDA38725/TDA38740 only support Linear format for VOUT related commands,
+ * with exponents in the range of -8 to -12 (see datasheet VOUT_MODE
+ * description). Direct format is not supported by this device.
+ */
+static int tda38740_identify(struct i2c_client *client,
+			     struct pmbus_driver_info *info)
+{
+	int vout_mode;
+
+	vout_mode = pmbus_read_byte_data(client, 0, PMBUS_VOUT_MODE);
+	if (vout_mode < 0 || vout_mode == 0xff)
+		return vout_mode < 0 ? vout_mode : -ENODEV;
+
+	if ((vout_mode >> 5) != 0)
+		return -ENODEV;
+
+	info->format[PSC_VOLTAGE_OUT] = linear;
+
+	return 0;
+}
+
+static struct pmbus_driver_info tda38740_info = {
+	.pages = 1,
+	.format[PSC_VOLTAGE_IN] = linear,
+	.format[PSC_CURRENT_OUT] = linear,
+	.format[PSC_CURRENT_IN] = linear,
+	.format[PSC_POWER] = linear,
+	.format[PSC_TEMPERATURE] = linear,
+	.func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT
+	    | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP
+	    | PMBUS_HAVE_IIN
+	    | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
+	    | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
+	    | PMBUS_HAVE_POUT | PMBUS_HAVE_PIN,
+	.identify = tda38740_identify,
+};
+
+static int tda38740_probe(struct i2c_client *client)
+{
+	struct tda38740_data *data;
+
+	data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+	memcpy(&data->info, &tda38740_info, sizeof(tda38740_info));
+
+	return pmbus_do_probe(client, &data->info);
+}
+
+static const struct i2c_device_id tda38740_id[] = {
+	{ .name = "tda38725"},
+	{ .name = "tda38740"},
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, tda38740_id);
+
+static const struct of_device_id __maybe_unused tda38740_of_match[] = {
+	{ .compatible = "infineon,tda38725"},
+	{ .compatible = "infineon,tda38740"},
+	{ },
+};
+MODULE_DEVICE_TABLE(of, tda38740_of_match);
+
+/* This is the driver that will be inserted */
+static struct i2c_driver tda38740_driver = {
+	.driver = {
+		.name = "tda38740",
+		.of_match_table = of_match_ptr(tda38740_of_match),
+	},
+	.probe = tda38740_probe,
+	.id_table = tda38740_id,
+};
+
+module_i2c_driver(tda38740_driver);
+
+MODULE_DESCRIPTION("PMBus driver for Infineon TDA38725/TDA38740");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS("PMBUS");

-- 
2.34.1