Add support for ltc4286 driver
Signed-off-by: Delphine CC Chiu <Delphine_CC_Chiu@xxxxxxxxxx>
---
drivers/hwmon/pmbus/Kconfig | 9 +++
drivers/hwmon/pmbus/Makefile | 1 +
drivers/hwmon/pmbus/ltc4286.c | 142 ++++++++++++++++++++++++++++++++++
3 files changed, 152 insertions(+)
create mode 100644 drivers/hwmon/pmbus/ltc4286.c
diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
index 59d9a7430499..1230d910d681 100644
--- a/drivers/hwmon/pmbus/Kconfig
+++ b/drivers/hwmon/pmbus/Kconfig
@@ -218,6 +218,15 @@ config SENSORS_LTC3815
This driver can also be built as a module. If so, the module will
be called ltc3815.
+config SENSORS_LTC4286
+ bool "Linear Technologies LTC4286"
+ help
+ If you say yes here you get hardware monitoring support for Linear
+ Technology LTC4286.
+
+ This driver can also be built as a module. If so, the module will
+ be called ltc4286.
+
config SENSORS_MAX15301
tristate "Maxim MAX15301"
help
diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
index 3ae019916267..540265539580 100644
--- a/drivers/hwmon/pmbus/Makefile
+++ b/drivers/hwmon/pmbus/Makefile
@@ -23,6 +23,7 @@ obj-$(CONFIG_SENSORS_LM25066) += lm25066.o
obj-$(CONFIG_SENSORS_LT7182S) += lt7182s.o
obj-$(CONFIG_SENSORS_LTC2978) += ltc2978.o
obj-$(CONFIG_SENSORS_LTC3815) += ltc3815.o
+obj-$(CONFIG_SENSORS_LTC4286) += ltc4286.o
obj-$(CONFIG_SENSORS_MAX15301) += max15301.o
obj-$(CONFIG_SENSORS_MAX16064) += max16064.o
obj-$(CONFIG_SENSORS_MAX16601) += max16601.o
diff --git a/drivers/hwmon/pmbus/ltc4286.c b/drivers/hwmon/pmbus/ltc4286.c
new file mode 100644
index 000000000000..474f4ec9107c
--- /dev/null
+++ b/drivers/hwmon/pmbus/ltc4286.c
@@ -0,0 +1,142 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Hardware monitoring driver for LTC4286 Hot-Swap Controller
+ *
+ * Copyright (c) 2023 Linear Technology
+ */
+
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pmbus.h>
+#include "pmbus.h"
+
+// LTC4286 register
+#define LTC4286_MFR_CONFIG1 (0xF2)
+
+// LTC4286 configuration
+#define VRANGE_SELECT (1 << 1)
+
+#define LTC4286_MFR_ID_SIZE 3
+
+enum chips { ltc4286, ltc4287 };
+
+static struct pmbus_driver_info ltc4286_info = {
+ .pages = 1,
+ .format[PSC_VOLTAGE_IN] = direct,
+ .format[PSC_VOLTAGE_OUT] = direct,
+ .format[PSC_CURRENT_OUT] = direct,
+ .format[PSC_POWER] = direct,
+ .format[PSC_TEMPERATURE] = direct,
+ .m[PSC_VOLTAGE_IN] = 32,
+ .b[PSC_VOLTAGE_IN] = 0,
+ .R[PSC_VOLTAGE_IN] = 1,
+ .m[PSC_VOLTAGE_OUT] = 32,
+ .b[PSC_VOLTAGE_OUT] = 0,
+ .R[PSC_VOLTAGE_OUT] = 1,
+ .m[PSC_CURRENT_OUT] = 1024,
+ .b[PSC_CURRENT_OUT] = 0,
+ .R[PSC_CURRENT_OUT] = 3 - 6,
+ .m[PSC_POWER] = 1,
+ .b[PSC_POWER] = 0,
+ .R[PSC_POWER] = 4 - 6,
+ .m[PSC_TEMPERATURE] = 1,
+ .b[PSC_TEMPERATURE] = 273.15,
+ .R[PSC_TEMPERATURE] = 0,
+ .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT |
+ PMBUS_HAVE_PIN | PMBUS_HAVE_TEMP,
+};
+
+static int ltc4286_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ int ret;
+ u8 block_buffer[I2C_SMBUS_BLOCK_MAX + 1];
+ struct device *dev = &client->dev;
+ struct pmbus_driver_info *info;
+ u32 rsense;
+
+ ret = i2c_smbus_read_block_data(client, PMBUS_MFR_ID, block_buffer);
+ if (ret < 0) {
+ dev_err(&client->dev, "failed to read manufacturer id\n");
+ return ret;
+ }
+
+ /* Refer to ltc4286 datasheet page 20
+ * the default manufacturer id is LTC
+ */
+ if (ret != LTC4286_MFR_ID_SIZE ||
+ strncmp(block_buffer, "LTC", LTC4286_MFR_ID_SIZE)) {
+ dev_err(&client->dev, "unsupported manufacturer id\n");
+ return -ENODEV;
+ }
+
+ ret = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, block_buffer);
+ if (ret < 0) {
+ dev_err(&client->dev, "failed to read manufacturer model\n");
+ return ret;
+ }
+
+ ret = of_property_read_u32(client->dev.of_node, "rsense-micro-ohms",
+ &rsense);
+ if (ret < 0)
+ return ret;
+
+ if (rsense == 0)
+ return -EINVAL;
+
+ info = <c4286_info;
+
+ /* Default of VRANGE_SELECT = 1 */
+ if (device_property_read_bool(dev, "vrange_select_25p6")) {
+ /* Setup MFR1 CONFIG register bit 1 VRANGE_SELECT */
+ ret = i2c_smbus_read_word_data(client, LTC4286_MFR_CONFIG1);
+ if (ret < 0) {
+ dev_err(&client->dev,
+ "failed to read manufacturer configuration one\n");
+ return ret;
+ }
+
+ ret &= ~VRANGE_SELECT; /* VRANGE_SELECT = 0, 25.6V */
+ i2c_smbus_write_word_data(client, LTC4286_MFR_CONFIG1, ret);
+
+ info->m[PSC_VOLTAGE_IN] = 128;
+ info->m[PSC_VOLTAGE_OUT] = 128;
+ info->m[PSC_POWER] = 4 * rsense;
+ } else {
+ info->m[PSC_POWER] = rsense;
+ }
+
+ info->m[PSC_CURRENT_OUT] = 1024 * rsense;
+
+ return pmbus_do_probe(client, info);
+}
+
+static const struct i2c_device_id ltc4286_id[] = { { "ltc4286", ltc4286 },
+ { "ltc4287", ltc4287 },
+ {} };
+MODULE_DEVICE_TABLE(i2c, ltc4286_id);
+
+static const struct of_device_id ltc4286_of_match[] = {
+ { .compatible = "lltc,ltc4286" },
+ { .compatible = "lltc,ltc4287" },
+ {}
+};
+
+/* This is the driver that will be inserted */
+static struct i2c_driver ltc4286_driver = {
+ .driver = {
+ .name = "ltc4286",
+ .of_match_table = ltc4286_of_match,
+ },
+ .probe = ltc4286_probe,
+ .id_table = ltc4286_id,
+};
+
+module_i2c_driver(ltc4286_driver);
+
+MODULE_AUTHOR("Delphine CC Chiu <Delphine_CC_Chiu@xxxxxxxxxx>");
+MODULE_DESCRIPTION("PMBUS driver for LTC4286 and compatibles");
+MODULE_LICENSE("GPL");
--
2.17.1
