Add pmbus support for Sony APS-379 power supplies. There are a few PMBUS
commands that return data that is undocumented/invalid so these need to
be rejected with -ENXIO. The READ_VOUT command returns data in linear11
format instead of linear16 so we need to workaround this.
Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
---
Notes:
Changes in v2:
- Simplify code per recommendations from Guenter
- Add driver documentation
Documentation/hwmon/aps-379.rst | 58 +++++++++++
Documentation/hwmon/index.rst | 1 +
drivers/hwmon/pmbus/Kconfig | 6 ++
drivers/hwmon/pmbus/Makefile | 1 +
drivers/hwmon/pmbus/aps-379.c | 168 ++++++++++++++++++++++++++++++++
5 files changed, 234 insertions(+)
create mode 100644 Documentation/hwmon/aps-379.rst
create mode 100644 drivers/hwmon/pmbus/aps-379.c
diff --git a/Documentation/hwmon/aps-379.rst b/Documentation/hwmon/aps-379.rst
new file mode 100644
index 000000000000..468ec5a98fd6
--- /dev/null
+++ b/Documentation/hwmon/aps-379.rst
@@ -0,0 +1,58 @@
+Kernel driver aps-379
+=====================
+
+Supported chips:
+
+ * Sony APS-379
+
+ Prefix: 'aps-379'
+
+ Addresses scanned: -
+
+ Authors:
+ - Chris Packham
+
+Description
+-----------
+
+This driver implements support for the PMBus monitor on the Sony APS-379
+modular power supply. The APS-379 deviates from the PMBus standard for the
+READ_VOUT command by using the linear11 format instead of linear16.
+
+The known supported PMBus commands are:
+
+=== ============================= ========= ======= =====
+Cmd Function Protocol Scaling Bytes
+=== ============================= ========= ======= =====
+01 On / Off Command (OPERATION) Byte R/W -- 1
+10 WRITE_PROTECT Byte R/W -- 1
+3B FAN_COMMAND_1 Word R/W -- 2
+46 Current Limit (in percent) Word R/W 2^0 2
+47 Current Limit Fault Response Byte R/W -- 1
+79 Alarm Data Bits (STATUS_WORD) Word Rd -- 2
+8B Output Voltage (READ_VOUT) Word Rd 2^-4 2
+8C Output Current (READ_IOUT) Word Rd 2^-2 2
+8D Power Supply Ambient Temp Word Rd 2^0 2
+90 READ_FAN_SPEED_1 Word Rd 2^6 2
+91 READ_FAN_SPEED_2 Word Rd 2^6 2
+96 Output Wattage (READ_POUT) Word Rd 2^1 2
+97 Input Wattage (READ_PIN) Word Rd 2^1 2
+9A Unit Model Number (MFR_MODEL) Block R/W -- 10
+9B Unit Revision Number Block R/W -- 10
+9E Unit Serial Number Block R/W -- 8
+99 Unit Manufacturer ID (MFR_ID) Block R/W -- 8
+D0 Unit Run Time Information Block Rd -- 4
+D5 Firmware Version Rd cust -- 8
+B0 User Data 1 (USER_DATA_00) Block R/W -- 4
+B1 User Data 2 (USER_DATA_01) Block R/W -- 4
+B2 User Data 3 (USER_DATA_02) Block R/W -- 4
+B3 User Data 4 (USER_DATA_03) Block R/W -- 4
+B4 User Data 5 (USER_DATA_04) Block R/W -- 4
+B5 User Data 6 (USER_DATA_05) Block R/W -- 4
+B6 User Data 7 (USER_DATA_06) Block R/W -- 4
+B7 User Data 8 (USER_DATA_07) Block R/W -- 4
+F0 Calibration command Byte R/W -- 1
+F1 Calibration data Word Wr 2^9 2
+F2 Unlock Calibration Byte Wr -- 1
+=== ============================= ========= ======= =====
+
diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst
index b2ca8513cfcd..2bc8d88b5724 100644
--- a/Documentation/hwmon/index.rst
+++ b/Documentation/hwmon/index.rst
@@ -41,6 +41,7 @@ Hardware Monitoring Kernel Drivers
adt7475
aht10
amc6821
+ aps-379
aquacomputer_d5next
asb100
asc7621
diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
index fc1273abe357..29076921e330 100644
--- a/drivers/hwmon/pmbus/Kconfig
+++ b/drivers/hwmon/pmbus/Kconfig
@@ -77,6 +77,12 @@ config SENSORS_ADP1050_REGULATOR
µModule regulators that can provide microprocessor power from 54V
power distribution architecture.
+config SENSORS_APS_379
+ tristate "Sony APS-379 Power Supplies"
+ help
+ If you say yes here you get hardware monitoring support for Sony
+ APS-379 Power Supplies.
+
config SENSORS_BEL_PFE
tristate "Bel PFE Compatible Power Supplies"
help
diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
index d6c86924f887..94f36c7069ec 100644
--- a/drivers/hwmon/pmbus/Makefile
+++ b/drivers/hwmon/pmbus/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_SENSORS_ACBEL_FSG032) += acbel-fsg032.o
obj-$(CONFIG_SENSORS_ADM1266) += adm1266.o
obj-$(CONFIG_SENSORS_ADM1275) += adm1275.o
obj-$(CONFIG_SENSORS_ADP1050) += adp1050.o
+obj-$(CONFIG_SENSORS_APS_379) += aps-379.o
obj-$(CONFIG_SENSORS_BEL_PFE) += bel-pfe.o
obj-$(CONFIG_SENSORS_BPA_RS600) += bpa-rs600.o
obj-$(CONFIG_SENSORS_DELTA_AHE50DC_FAN) += delta-ahe50dc-fan.o
diff --git a/drivers/hwmon/pmbus/aps-379.c b/drivers/hwmon/pmbus/aps-379.c
new file mode 100644
index 000000000000..edc489558437
--- /dev/null
+++ b/drivers/hwmon/pmbus/aps-379.c
@@ -0,0 +1,168 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Hardware monitoring driver for Sony APS-379 Power Supplies
+ *
+ * Copyright 2026 Allied Telesis Labs
+ */
+
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pmbus.h>
+#include "pmbus.h"
+
+struct aps_379_data {
+ struct pmbus_driver_info info;
+ u8 vout_linear_exponent;
+};
+
+#define to_aps_379_data(x) container_of(x, struct aps_379_data, info)
+
+static const struct i2c_device_id aps_379_id[] = {
+ { "aps-379", 0 },
+ {},
+};
+
+static int aps_379_read_byte_data(struct i2c_client *client, int page, int reg)
+{
+ const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
+ struct aps_379_data *data = to_aps_379_data(info);
+
+ switch (reg) {
+ case PMBUS_VOUT_MODE:
+ /*
+ * The VOUT format used by the chip is linear11,
+ * not linear16. Report that VOUT is in linear mode
+ * and return exponent value extracted while probing
+ * the chip.
+ */
+ return data->vout_linear_exponent;
+ default:
+ return -ENODATA;
+ }
+}
+
+/*
+ * The APS-379 uses linear11 format instead of linear16. We've reported the exponent
+ * via the PMBUS_VOUT_MODE so we just return the mantissa here.
+ */
+static int aps_379_read_vout(struct i2c_client *client)
+{
+ int ret;
+
+ ret = pmbus_read_word_data(client, 0, 0xff, PMBUS_READ_VOUT);
+ if (ret < 0)
+ return ret;
+
+ return sign_extend32(ret & 0x7ff, 11);
+}
+
+static int aps_379_read_word_data(struct i2c_client *client, int page, int phase, int reg)
+{
+ switch (reg) {
+ case PMBUS_VOUT_UV_WARN_LIMIT:
+ case PMBUS_VOUT_OV_WARN_LIMIT:
+ case PMBUS_VOUT_UV_FAULT_LIMIT:
+ case PMBUS_VOUT_OV_FAULT_LIMIT:
+ case PMBUS_PIN_OP_WARN_LIMIT:
+ case PMBUS_POUT_OP_WARN_LIMIT:
+ case PMBUS_MFR_IIN_MAX:
+ case PMBUS_MFR_PIN_MAX:
+ case PMBUS_MFR_VOUT_MIN:
+ case PMBUS_MFR_VOUT_MAX:
+ case PMBUS_MFR_IOUT_MAX:
+ case PMBUS_MFR_POUT_MAX:
+ case PMBUS_MFR_MAX_TEMP_1:
+ /* These commands return data but it is invalid/un-documented */
+ return -ENXIO;
+ case PMBUS_READ_VOUT:
+ return aps_379_read_vout(client);
+ default:
+ if (reg >= PMBUS_VIRT_BASE)
+ return -ENXIO;
+ else
+ return -ENODATA;
+ }
+}
+
+static struct pmbus_driver_info aps_379_info = {
+ .pages = 1,
+ .format[PSC_VOLTAGE_OUT] = linear,
+ .format[PSC_CURRENT_OUT] = linear,
+ .format[PSC_POWER] = linear,
+ .format[PSC_TEMPERATURE] = linear,
+ .format[PSC_FAN] = linear,
+ .func[0] = PMBUS_HAVE_VOUT |
+ PMBUS_HAVE_IOUT |
+ PMBUS_HAVE_PIN | PMBUS_HAVE_POUT |
+ PMBUS_HAVE_TEMP |
+ PMBUS_HAVE_FAN12,
+ .read_byte_data = aps_379_read_byte_data,
+ .read_word_data = aps_379_read_word_data,
+};
+
+static int aps_379_probe(struct i2c_client *client)
+{
+ struct device *dev = &client->dev;
+ struct pmbus_driver_info *info;
+ struct aps_379_data *data;
+ u8 buf[I2C_SMBUS_BLOCK_MAX + 1];
+ int ret;
+
+ data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ memcpy(&data->info, &aps_379_info, sizeof(*info));
+ info = &data->info;
+
+ if (!i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_READ_BYTE_DATA
+ | I2C_FUNC_SMBUS_READ_WORD_DATA
+ | I2C_FUNC_SMBUS_READ_BLOCK_DATA))
+ return -ENODEV;
+
+ ret = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, buf);
+ if (ret < 0) {
+ dev_err(dev, "Failed to read Manufacturer Model\n");
+ return ret;
+ }
+
+ if (strncasecmp(buf, aps_379_id[0].name, strlen(aps_379_id[0].name)) != 0) {
+ buf[ret] = '\0';
+ dev_err(dev, "Unsupported Manufacturer Model '%s'\n", buf);
+ return -ENODEV;
+ }
+
+ ret = i2c_smbus_read_word_data(client, PMBUS_READ_VOUT);
+ if (ret < 0) {
+ dev_err(dev, "Can't get vout exponent.\n");
+ return ret;
+ }
+ data->vout_linear_exponent = (u8)((ret >> 11) & 0x1f);
+
+ return pmbus_do_probe(client, info);
+}
+
+static const struct of_device_id __maybe_unused aps_379_of_match[] = {
+ { .compatible = "sony,aps-379" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, aps_379_of_match);
+
+static struct i2c_driver aps_379_driver = {
+ .driver = {
+ .name = "aps-379",
+ .of_match_table = of_match_ptr(aps_379_of_match),
+ },
+ .probe = aps_379_probe,
+ .id_table = aps_379_id,
+};
+
+module_i2c_driver(aps_379_driver);
+
+MODULE_AUTHOR("Chris Packham");
+MODULE_DESCRIPTION("PMBus driver for Sony APS-379");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS("PMBUS");
--
2.53.0On 3/31/26 19:42, Chris Packham wrote:
> Add pmbus support for Sony APS-379 power supplies. There are a few PMBUS
> commands that return data that is undocumented/invalid so these need to
> be rejected with -ENXIO. The READ_VOUT command returns data in linear11
> format instead of linear16 so we need to workaround this.
>
> Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
> ---
>
Here is the AI feedback:
https://sashiko.dev/#/patchset/20260401024214.804237-1-chris.packham%40alliedtelesis.co.nz
All good points ...
Guenter
> Notes:
> Changes in v2:
> - Simplify code per recommendations from Guenter
> - Add driver documentation
>
> Documentation/hwmon/aps-379.rst | 58 +++++++++++
> Documentation/hwmon/index.rst | 1 +
> drivers/hwmon/pmbus/Kconfig | 6 ++
> drivers/hwmon/pmbus/Makefile | 1 +
> drivers/hwmon/pmbus/aps-379.c | 168 ++++++++++++++++++++++++++++++++
> 5 files changed, 234 insertions(+)
> create mode 100644 Documentation/hwmon/aps-379.rst
> create mode 100644 drivers/hwmon/pmbus/aps-379.c
>
> diff --git a/Documentation/hwmon/aps-379.rst b/Documentation/hwmon/aps-379.rst
> new file mode 100644
> index 000000000000..468ec5a98fd6
> --- /dev/null
> +++ b/Documentation/hwmon/aps-379.rst
> @@ -0,0 +1,58 @@
> +Kernel driver aps-379
> +=====================
> +
> +Supported chips:
> +
> + * Sony APS-379
> +
> + Prefix: 'aps-379'
> +
> + Addresses scanned: -
> +
> + Authors:
> + - Chris Packham
> +
> +Description
> +-----------
> +
> +This driver implements support for the PMBus monitor on the Sony APS-379
> +modular power supply. The APS-379 deviates from the PMBus standard for the
> +READ_VOUT command by using the linear11 format instead of linear16.
> +
> +The known supported PMBus commands are:
> +
> +=== ============================= ========= ======= =====
> +Cmd Function Protocol Scaling Bytes
> +=== ============================= ========= ======= =====
> +01 On / Off Command (OPERATION) Byte R/W -- 1
> +10 WRITE_PROTECT Byte R/W -- 1
> +3B FAN_COMMAND_1 Word R/W -- 2
> +46 Current Limit (in percent) Word R/W 2^0 2
> +47 Current Limit Fault Response Byte R/W -- 1
> +79 Alarm Data Bits (STATUS_WORD) Word Rd -- 2
> +8B Output Voltage (READ_VOUT) Word Rd 2^-4 2
> +8C Output Current (READ_IOUT) Word Rd 2^-2 2
> +8D Power Supply Ambient Temp Word Rd 2^0 2
> +90 READ_FAN_SPEED_1 Word Rd 2^6 2
> +91 READ_FAN_SPEED_2 Word Rd 2^6 2
> +96 Output Wattage (READ_POUT) Word Rd 2^1 2
> +97 Input Wattage (READ_PIN) Word Rd 2^1 2
> +9A Unit Model Number (MFR_MODEL) Block R/W -- 10
> +9B Unit Revision Number Block R/W -- 10
> +9E Unit Serial Number Block R/W -- 8
> +99 Unit Manufacturer ID (MFR_ID) Block R/W -- 8
> +D0 Unit Run Time Information Block Rd -- 4
> +D5 Firmware Version Rd cust -- 8
> +B0 User Data 1 (USER_DATA_00) Block R/W -- 4
> +B1 User Data 2 (USER_DATA_01) Block R/W -- 4
> +B2 User Data 3 (USER_DATA_02) Block R/W -- 4
> +B3 User Data 4 (USER_DATA_03) Block R/W -- 4
> +B4 User Data 5 (USER_DATA_04) Block R/W -- 4
> +B5 User Data 6 (USER_DATA_05) Block R/W -- 4
> +B6 User Data 7 (USER_DATA_06) Block R/W -- 4
> +B7 User Data 8 (USER_DATA_07) Block R/W -- 4
> +F0 Calibration command Byte R/W -- 1
> +F1 Calibration data Word Wr 2^9 2
> +F2 Unlock Calibration Byte Wr -- 1
> +=== ============================= ========= ======= =====
> +
> diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst
> index b2ca8513cfcd..2bc8d88b5724 100644
> --- a/Documentation/hwmon/index.rst
> +++ b/Documentation/hwmon/index.rst
> @@ -41,6 +41,7 @@ Hardware Monitoring Kernel Drivers
> adt7475
> aht10
> amc6821
> + aps-379
> aquacomputer_d5next
> asb100
> asc7621
> diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
> index fc1273abe357..29076921e330 100644
> --- a/drivers/hwmon/pmbus/Kconfig
> +++ b/drivers/hwmon/pmbus/Kconfig
> @@ -77,6 +77,12 @@ config SENSORS_ADP1050_REGULATOR
> µModule regulators that can provide microprocessor power from 54V
> power distribution architecture.
>
> +config SENSORS_APS_379
> + tristate "Sony APS-379 Power Supplies"
> + help
> + If you say yes here you get hardware monitoring support for Sony
> + APS-379 Power Supplies.
> +
> config SENSORS_BEL_PFE
> tristate "Bel PFE Compatible Power Supplies"
> help
> diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
> index d6c86924f887..94f36c7069ec 100644
> --- a/drivers/hwmon/pmbus/Makefile
> +++ b/drivers/hwmon/pmbus/Makefile
> @@ -9,6 +9,7 @@ obj-$(CONFIG_SENSORS_ACBEL_FSG032) += acbel-fsg032.o
> obj-$(CONFIG_SENSORS_ADM1266) += adm1266.o
> obj-$(CONFIG_SENSORS_ADM1275) += adm1275.o
> obj-$(CONFIG_SENSORS_ADP1050) += adp1050.o
> +obj-$(CONFIG_SENSORS_APS_379) += aps-379.o
> obj-$(CONFIG_SENSORS_BEL_PFE) += bel-pfe.o
> obj-$(CONFIG_SENSORS_BPA_RS600) += bpa-rs600.o
> obj-$(CONFIG_SENSORS_DELTA_AHE50DC_FAN) += delta-ahe50dc-fan.o
> diff --git a/drivers/hwmon/pmbus/aps-379.c b/drivers/hwmon/pmbus/aps-379.c
> new file mode 100644
> index 000000000000..edc489558437
> --- /dev/null
> +++ b/drivers/hwmon/pmbus/aps-379.c
> @@ -0,0 +1,168 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Hardware monitoring driver for Sony APS-379 Power Supplies
> + *
> + * Copyright 2026 Allied Telesis Labs
> + */
> +
> +#include <linux/i2c.h>
> +#include <linux/init.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/pmbus.h>
> +#include "pmbus.h"
> +
> +struct aps_379_data {
> + struct pmbus_driver_info info;
> + u8 vout_linear_exponent;
> +};
> +
> +#define to_aps_379_data(x) container_of(x, struct aps_379_data, info)
> +
> +static const struct i2c_device_id aps_379_id[] = {
> + { "aps-379", 0 },
> + {},
> +};
> +
> +static int aps_379_read_byte_data(struct i2c_client *client, int page, int reg)
> +{
> + const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
> + struct aps_379_data *data = to_aps_379_data(info);
> +
> + switch (reg) {
> + case PMBUS_VOUT_MODE:
> + /*
> + * The VOUT format used by the chip is linear11,
> + * not linear16. Report that VOUT is in linear mode
> + * and return exponent value extracted while probing
> + * the chip.
> + */
> + return data->vout_linear_exponent;
> + default:
> + return -ENODATA;
> + }
> +}
> +
> +/*
> + * The APS-379 uses linear11 format instead of linear16. We've reported the exponent
> + * via the PMBUS_VOUT_MODE so we just return the mantissa here.
> + */
> +static int aps_379_read_vout(struct i2c_client *client)
> +{
> + int ret;
> +
> + ret = pmbus_read_word_data(client, 0, 0xff, PMBUS_READ_VOUT);
> + if (ret < 0)
> + return ret;
> +
> + return sign_extend32(ret & 0x7ff, 11);
> +}
> +
> +static int aps_379_read_word_data(struct i2c_client *client, int page, int phase, int reg)
> +{
> + switch (reg) {
> + case PMBUS_VOUT_UV_WARN_LIMIT:
> + case PMBUS_VOUT_OV_WARN_LIMIT:
> + case PMBUS_VOUT_UV_FAULT_LIMIT:
> + case PMBUS_VOUT_OV_FAULT_LIMIT:
> + case PMBUS_PIN_OP_WARN_LIMIT:
> + case PMBUS_POUT_OP_WARN_LIMIT:
> + case PMBUS_MFR_IIN_MAX:
> + case PMBUS_MFR_PIN_MAX:
> + case PMBUS_MFR_VOUT_MIN:
> + case PMBUS_MFR_VOUT_MAX:
> + case PMBUS_MFR_IOUT_MAX:
> + case PMBUS_MFR_POUT_MAX:
> + case PMBUS_MFR_MAX_TEMP_1:
> + /* These commands return data but it is invalid/un-documented */
> + return -ENXIO;
> + case PMBUS_READ_VOUT:
> + return aps_379_read_vout(client);
> + default:
> + if (reg >= PMBUS_VIRT_BASE)
> + return -ENXIO;
> + else
> + return -ENODATA;
> + }
> +}
> +
> +static struct pmbus_driver_info aps_379_info = {
> + .pages = 1,
> + .format[PSC_VOLTAGE_OUT] = linear,
> + .format[PSC_CURRENT_OUT] = linear,
> + .format[PSC_POWER] = linear,
> + .format[PSC_TEMPERATURE] = linear,
> + .format[PSC_FAN] = linear,
> + .func[0] = PMBUS_HAVE_VOUT |
> + PMBUS_HAVE_IOUT |
> + PMBUS_HAVE_PIN | PMBUS_HAVE_POUT |
> + PMBUS_HAVE_TEMP |
> + PMBUS_HAVE_FAN12,
> + .read_byte_data = aps_379_read_byte_data,
> + .read_word_data = aps_379_read_word_data,
> +};
> +
> +static int aps_379_probe(struct i2c_client *client)
> +{
> + struct device *dev = &client->dev;
> + struct pmbus_driver_info *info;
> + struct aps_379_data *data;
> + u8 buf[I2C_SMBUS_BLOCK_MAX + 1];
> + int ret;
> +
> + data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
> + if (!data)
> + return -ENOMEM;
> +
> + memcpy(&data->info, &aps_379_info, sizeof(*info));
> + info = &data->info;
> +
> + if (!i2c_check_functionality(client->adapter,
> + I2C_FUNC_SMBUS_READ_BYTE_DATA
> + | I2C_FUNC_SMBUS_READ_WORD_DATA
> + | I2C_FUNC_SMBUS_READ_BLOCK_DATA))
> + return -ENODEV;
> +
> + ret = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, buf);
> + if (ret < 0) {
> + dev_err(dev, "Failed to read Manufacturer Model\n");
> + return ret;
> + }
> +
> + if (strncasecmp(buf, aps_379_id[0].name, strlen(aps_379_id[0].name)) != 0) {
> + buf[ret] = '\0';
> + dev_err(dev, "Unsupported Manufacturer Model '%s'\n", buf);
> + return -ENODEV;
> + }
> +
> + ret = i2c_smbus_read_word_data(client, PMBUS_READ_VOUT);
> + if (ret < 0) {
> + dev_err(dev, "Can't get vout exponent.\n");
> + return ret;
> + }
> + data->vout_linear_exponent = (u8)((ret >> 11) & 0x1f);
> +
> + return pmbus_do_probe(client, info);
> +}
> +
> +static const struct of_device_id __maybe_unused aps_379_of_match[] = {
> + { .compatible = "sony,aps-379" },
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, aps_379_of_match);
> +
> +static struct i2c_driver aps_379_driver = {
> + .driver = {
> + .name = "aps-379",
> + .of_match_table = of_match_ptr(aps_379_of_match),
> + },
> + .probe = aps_379_probe,
> + .id_table = aps_379_id,
> +};
> +
> +module_i2c_driver(aps_379_driver);
> +
> +MODULE_AUTHOR("Chris Packham");
> +MODULE_DESCRIPTION("PMBus driver for Sony APS-379");
> +MODULE_LICENSE("GPL");
> +MODULE_IMPORT_NS("PMBUS");
On 01/04/2026 16:58, Guenter Roeck wrote:
> On 3/31/26 19:42, Chris Packham wrote:
>> Add pmbus support for Sony APS-379 power supplies. There are a few PMBUS
>> commands that return data that is undocumented/invalid so these need to
>> be rejected with -ENXIO. The READ_VOUT command returns data in linear11
>> format instead of linear16 so we need to workaround this.
>>
>> Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
>> ---
>>
>
> Here is the AI feedback:
>
> https://scanmail.trustwave.com/?c=20988&d=-5fM6Qyi3kX42boReXvp_F06nhM1_AVskUmlQ71c3g&u=https%3a%2f%2fsashiko%2edev%2f%23%2fpatchset%2f20260401024214%2e804237-1-chris%2epackham%2540alliedtelesis%2eco%2enz
>
>
> All good points ...
Yep agreed. The lack of MODULE_DEVICE_TABLE() is an omission on my part.
The other two are arguably style but I find myself agreeing with both
suggestions. I'll wait to send a v3.
>
>
> Guenter
>
>> Notes:
>> Changes in v2:
>> - Simplify code per recommendations from Guenter
>> - Add driver documentation
>>
>> Documentation/hwmon/aps-379.rst | 58 +++++++++++
>> Documentation/hwmon/index.rst | 1 +
>> drivers/hwmon/pmbus/Kconfig | 6 ++
>> drivers/hwmon/pmbus/Makefile | 1 +
>> drivers/hwmon/pmbus/aps-379.c | 168 ++++++++++++++++++++++++++++++++
>> 5 files changed, 234 insertions(+)
>> create mode 100644 Documentation/hwmon/aps-379.rst
>> create mode 100644 drivers/hwmon/pmbus/aps-379.c
>>
>> diff --git a/Documentation/hwmon/aps-379.rst
>> b/Documentation/hwmon/aps-379.rst
>> new file mode 100644
>> index 000000000000..468ec5a98fd6
>> --- /dev/null
>> +++ b/Documentation/hwmon/aps-379.rst
>> @@ -0,0 +1,58 @@
>> +Kernel driver aps-379
>> +=====================
>> +
>> +Supported chips:
>> +
>> + * Sony APS-379
>> +
>> + Prefix: 'aps-379'
>> +
>> + Addresses scanned: -
>> +
>> + Authors:
>> + - Chris Packham
>> +
>> +Description
>> +-----------
>> +
>> +This driver implements support for the PMBus monitor on the Sony
>> APS-379
>> +modular power supply. The APS-379 deviates from the PMBus standard
>> for the
>> +READ_VOUT command by using the linear11 format instead of linear16.
>> +
>> +The known supported PMBus commands are:
>> +
>> +=== ============================= ========= ======= =====
>> +Cmd Function Protocol Scaling Bytes
>> +=== ============================= ========= ======= =====
>> +01 On / Off Command (OPERATION) Byte R/W -- 1
>> +10 WRITE_PROTECT Byte R/W -- 1
>> +3B FAN_COMMAND_1 Word R/W -- 2
>> +46 Current Limit (in percent) Word R/W 2^0 2
>> +47 Current Limit Fault Response Byte R/W -- 1
>> +79 Alarm Data Bits (STATUS_WORD) Word Rd -- 2
>> +8B Output Voltage (READ_VOUT) Word Rd 2^-4 2
>> +8C Output Current (READ_IOUT) Word Rd 2^-2 2
>> +8D Power Supply Ambient Temp Word Rd 2^0 2
>> +90 READ_FAN_SPEED_1 Word Rd 2^6 2
>> +91 READ_FAN_SPEED_2 Word Rd 2^6 2
>> +96 Output Wattage (READ_POUT) Word Rd 2^1 2
>> +97 Input Wattage (READ_PIN) Word Rd 2^1 2
>> +9A Unit Model Number (MFR_MODEL) Block R/W -- 10
>> +9B Unit Revision Number Block R/W -- 10
>> +9E Unit Serial Number Block R/W -- 8
>> +99 Unit Manufacturer ID (MFR_ID) Block R/W -- 8
>> +D0 Unit Run Time Information Block Rd -- 4
>> +D5 Firmware Version Rd cust -- 8
>> +B0 User Data 1 (USER_DATA_00) Block R/W -- 4
>> +B1 User Data 2 (USER_DATA_01) Block R/W -- 4
>> +B2 User Data 3 (USER_DATA_02) Block R/W -- 4
>> +B3 User Data 4 (USER_DATA_03) Block R/W -- 4
>> +B4 User Data 5 (USER_DATA_04) Block R/W -- 4
>> +B5 User Data 6 (USER_DATA_05) Block R/W -- 4
>> +B6 User Data 7 (USER_DATA_06) Block R/W -- 4
>> +B7 User Data 8 (USER_DATA_07) Block R/W -- 4
>> +F0 Calibration command Byte R/W -- 1
>> +F1 Calibration data Word Wr 2^9 2
>> +F2 Unlock Calibration Byte Wr -- 1
>> +=== ============================= ========= ======= =====
>> +
>> diff --git a/Documentation/hwmon/index.rst
>> b/Documentation/hwmon/index.rst
>> index b2ca8513cfcd..2bc8d88b5724 100644
>> --- a/Documentation/hwmon/index.rst
>> +++ b/Documentation/hwmon/index.rst
>> @@ -41,6 +41,7 @@ Hardware Monitoring Kernel Drivers
>> adt7475
>> aht10
>> amc6821
>> + aps-379
>> aquacomputer_d5next
>> asb100
>> asc7621
>> diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
>> index fc1273abe357..29076921e330 100644
>> --- a/drivers/hwmon/pmbus/Kconfig
>> +++ b/drivers/hwmon/pmbus/Kconfig
>> @@ -77,6 +77,12 @@ config SENSORS_ADP1050_REGULATOR
>> µModule regulators that can provide microprocessor power from
>> 54V
>> power distribution architecture.
>> +config SENSORS_APS_379
>> + tristate "Sony APS-379 Power Supplies"
>> + help
>> + If you say yes here you get hardware monitoring support for Sony
>> + APS-379 Power Supplies.
>> +
>> config SENSORS_BEL_PFE
>> tristate "Bel PFE Compatible Power Supplies"
>> help
>> diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
>> index d6c86924f887..94f36c7069ec 100644
>> --- a/drivers/hwmon/pmbus/Makefile
>> +++ b/drivers/hwmon/pmbus/Makefile
>> @@ -9,6 +9,7 @@ obj-$(CONFIG_SENSORS_ACBEL_FSG032) += acbel-fsg032.o
>> obj-$(CONFIG_SENSORS_ADM1266) += adm1266.o
>> obj-$(CONFIG_SENSORS_ADM1275) += adm1275.o
>> obj-$(CONFIG_SENSORS_ADP1050) += adp1050.o
>> +obj-$(CONFIG_SENSORS_APS_379) += aps-379.o
>> obj-$(CONFIG_SENSORS_BEL_PFE) += bel-pfe.o
>> obj-$(CONFIG_SENSORS_BPA_RS600) += bpa-rs600.o
>> obj-$(CONFIG_SENSORS_DELTA_AHE50DC_FAN) += delta-ahe50dc-fan.o
>> diff --git a/drivers/hwmon/pmbus/aps-379.c
>> b/drivers/hwmon/pmbus/aps-379.c
>> new file mode 100644
>> index 000000000000..edc489558437
>> --- /dev/null
>> +++ b/drivers/hwmon/pmbus/aps-379.c
>> @@ -0,0 +1,168 @@
>> +// SPDX-License-Identifier: GPL-2.0-or-later
>> +/*
>> + * Hardware monitoring driver for Sony APS-379 Power Supplies
>> + *
>> + * Copyright 2026 Allied Telesis Labs
>> + */
>> +
>> +#include <linux/i2c.h>
>> +#include <linux/init.h>
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/pmbus.h>
>> +#include "pmbus.h"
>> +
>> +struct aps_379_data {
>> + struct pmbus_driver_info info;
>> + u8 vout_linear_exponent;
>> +};
>> +
>> +#define to_aps_379_data(x) container_of(x, struct aps_379_data, info)
>> +
>> +static const struct i2c_device_id aps_379_id[] = {
>> + { "aps-379", 0 },
>> + {},
>> +};
>> +
>> +static int aps_379_read_byte_data(struct i2c_client *client, int
>> page, int reg)
>> +{
>> + const struct pmbus_driver_info *info =
>> pmbus_get_driver_info(client);
>> + struct aps_379_data *data = to_aps_379_data(info);
>> +
>> + switch (reg) {
>> + case PMBUS_VOUT_MODE:
>> + /*
>> + * The VOUT format used by the chip is linear11,
>> + * not linear16. Report that VOUT is in linear mode
>> + * and return exponent value extracted while probing
>> + * the chip.
>> + */
>> + return data->vout_linear_exponent;
>> + default:
>> + return -ENODATA;
>> + }
>> +}
>> +
>> +/*
>> + * The APS-379 uses linear11 format instead of linear16. We've
>> reported the exponent
>> + * via the PMBUS_VOUT_MODE so we just return the mantissa here.
>> + */
>> +static int aps_379_read_vout(struct i2c_client *client)
>> +{
>> + int ret;
>> +
>> + ret = pmbus_read_word_data(client, 0, 0xff, PMBUS_READ_VOUT);
>> + if (ret < 0)
>> + return ret;
>> +
>> + return sign_extend32(ret & 0x7ff, 11);
>> +}
>> +
>> +static int aps_379_read_word_data(struct i2c_client *client, int
>> page, int phase, int reg)
>> +{
>> + switch (reg) {
>> + case PMBUS_VOUT_UV_WARN_LIMIT:
>> + case PMBUS_VOUT_OV_WARN_LIMIT:
>> + case PMBUS_VOUT_UV_FAULT_LIMIT:
>> + case PMBUS_VOUT_OV_FAULT_LIMIT:
>> + case PMBUS_PIN_OP_WARN_LIMIT:
>> + case PMBUS_POUT_OP_WARN_LIMIT:
>> + case PMBUS_MFR_IIN_MAX:
>> + case PMBUS_MFR_PIN_MAX:
>> + case PMBUS_MFR_VOUT_MIN:
>> + case PMBUS_MFR_VOUT_MAX:
>> + case PMBUS_MFR_IOUT_MAX:
>> + case PMBUS_MFR_POUT_MAX:
>> + case PMBUS_MFR_MAX_TEMP_1:
>> + /* These commands return data but it is
>> invalid/un-documented */
>> + return -ENXIO;
>> + case PMBUS_READ_VOUT:
>> + return aps_379_read_vout(client);
>> + default:
>> + if (reg >= PMBUS_VIRT_BASE)
>> + return -ENXIO;
>> + else
>> + return -ENODATA;
>> + }
>> +}
>> +
>> +static struct pmbus_driver_info aps_379_info = {
>> + .pages = 1,
>> + .format[PSC_VOLTAGE_OUT] = linear,
>> + .format[PSC_CURRENT_OUT] = linear,
>> + .format[PSC_POWER] = linear,
>> + .format[PSC_TEMPERATURE] = linear,
>> + .format[PSC_FAN] = linear,
>> + .func[0] = PMBUS_HAVE_VOUT |
>> + PMBUS_HAVE_IOUT |
>> + PMBUS_HAVE_PIN | PMBUS_HAVE_POUT |
>> + PMBUS_HAVE_TEMP |
>> + PMBUS_HAVE_FAN12,
>> + .read_byte_data = aps_379_read_byte_data,
>> + .read_word_data = aps_379_read_word_data,
>> +};
>> +
>> +static int aps_379_probe(struct i2c_client *client)
>> +{
>> + struct device *dev = &client->dev;
>> + struct pmbus_driver_info *info;
>> + struct aps_379_data *data;
>> + u8 buf[I2C_SMBUS_BLOCK_MAX + 1];
>> + int ret;
>> +
>> + data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
>> + if (!data)
>> + return -ENOMEM;
>> +
>> + memcpy(&data->info, &aps_379_info, sizeof(*info));
>> + info = &data->info;
>> +
>> + if (!i2c_check_functionality(client->adapter,
>> + I2C_FUNC_SMBUS_READ_BYTE_DATA
>> + | I2C_FUNC_SMBUS_READ_WORD_DATA
>> + | I2C_FUNC_SMBUS_READ_BLOCK_DATA))
>> + return -ENODEV;
>> +
>> + ret = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, buf);
>> + if (ret < 0) {
>> + dev_err(dev, "Failed to read Manufacturer Model\n");
>> + return ret;
>> + }
>> +
>> + if (strncasecmp(buf,
>> http://scanmail.trustwave.com/?c=20988&d=-5fM6Qyi3kX42boReXvp_F06nhM1_AVskRzwE-YPiQ&u=http%3a%2f%2faps%5f379%5fid%5b0%5d%2ename
>> strlen(aps_379_id[0].name)) != 0) {
>> + buf[ret] = '\0';
>> + dev_err(dev, "Unsupported Manufacturer Model '%s'\n", buf);
>> + return -ENODEV;
>> + }
>> +
>> + ret = i2c_smbus_read_word_data(client, PMBUS_READ_VOUT);
>> + if (ret < 0) {
>> + dev_err(dev, "Can't get vout exponent.\n");
>> + return ret;
>> + }
>> + data->vout_linear_exponent = (u8)((ret >> 11) & 0x1f);
>> +
>> + return pmbus_do_probe(client, info);
>> +}
>> +
>> +static const struct of_device_id __maybe_unused aps_379_of_match[] = {
>> + { .compatible = "sony,aps-379" },
>> + {},
>> +};
>> +MODULE_DEVICE_TABLE(of, aps_379_of_match);
>> +
>> +static struct i2c_driver aps_379_driver = {
>> + .driver = {
>> + .name = "aps-379",
>> + .of_match_table = of_match_ptr(aps_379_of_match),
>> + },
>> + .probe = aps_379_probe,
>> + .id_table = aps_379_id,
>> +};
>> +
>> +module_i2c_driver(aps_379_driver);
>> +
>> +MODULE_AUTHOR("Chris Packham");
>> +MODULE_DESCRIPTION("PMBus driver for Sony APS-379");
>> +MODULE_LICENSE("GPL");
>> +MODULE_IMPORT_NS("PMBUS");
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