Re: [PATCH v4 5/5] hwmon: pmbus driver documentation

[Jonathan Cameron <jic23@cam.ac.uk>]

Looks fine to me. Do you want to mention the fan stuff somewhere?


On 02/17/11 19:00, Guenter Roeck wrote:
> Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
> ---
>  Documentation/hwmon/pmbus |  213 +++++++++++++++++++++++++++++++++++++++++++++
>  1 files changed, 213 insertions(+), 0 deletions(-)
>  create mode 100644 Documentation/hwmon/pmbus
> 
> diff --git a/Documentation/hwmon/pmbus b/Documentation/hwmon/pmbus
> new file mode 100644
> index 0000000..00ed7d4
> --- /dev/null
> +++ b/Documentation/hwmon/pmbus
> @@ -0,0 +1,213 @@
> +Kernel driver pmbus
> +====================
> +
> +Supported chips:
> +  * Ericsson BMR45X series
> +    DC/DC Converter
> +    Prefixes: 'bmr450', 'bmr451', 'bmr453', 'bmr454'
> +    Addresses scanned: -
> +    Datasheet:
> + http://archive.ericsson.net/service/internet/picov/get?DocNo=28701-EN/LZT146395
> +  * Linear Technology LTC2978
> +    Octal PMBus Power Supply Monitor and Controller
> +    Prefix: 'ltc2978'
> +    Addresses scanned: -
> +    Datasheet: http://cds.linear.com/docs/Datasheet/2978fa.pdf
> +  * Maxim MAX16064
> +    Quad Power-Supply Controller
> +    Prefix: 'max16064'
> +    Addresses scanned: -
> +    Datasheet: http://datasheets.maxim-ic.com/en/ds/MAX16064.pdf
> +  * Maxim MAX34440
> +    PMBus 6-Channel Power-Supply Manager
> +    Prefixes: 'max34440'
> +    Addresses scanned: -
> +    Datasheet: http://datasheets.maxim-ic.com/en/ds/MAX34440.pdf
> +  * Maxim MAX34441
> +    PMBus 5-Channel Power-Supply Manager and Intelligent Fan Controller
> +    Prefixes: 'max34441'
> +    Addresses scanned: -
> +    Datasheet: http://datasheets.maxim-ic.com/en/ds/MAX34441.pdf
> +  * Maxim MAX8688
> +    Digital Power-Supply Controller/Monitor
> +    Prefix: 'max8688'
> +    Addresses scanned: -
> +    Datasheet: http://datasheets.maxim-ic.com/en/ds/MAX8688.pdf
> +  * Generic PMBus devices
> +    Prefix: 'pmbus'
> +    Addresses scanned: -
> +    Datasheet: n.a.
> +
> +Author: Guenter Roeck <guenter.roeck@ericsson.com>
> +
> +
> +Description
> +-----------
> +
> +This driver supports hardware montoring for various PMBus compliant devices.
> +It supports voltage, current, power, and temperature sensors as supported
> +by the device.
Mention fan stuff?
> +
> +Each monitored channel has its own high and low limits, plus a critical
> +limit.
> +
> +
> +Usage Notes
> +-----------
> +
> +This driver does not probe for PMBus devices, since there is no register
> +which can be safely used to identify the chip (The MFG_ID register is not
> +supported by all chips), and since there is no well defined address range for
> +PMBus devices. You will have to instantiate the devices explicitly.
> +
> +Example: the following will load the driver for an LTC2978 at address 0x60
> +on I2C bus #1:
> +$ modprobe pmbus
> +$ echo ltc2978 0x60 > /sys/bus/i2c/devices/i2c-1/new_device
> +
> +
> +Platform data support
> +---------------------
> +
> +Support for additional PMBus chips can be added by defining chip parameters in
> +a new chip specific driver file. For example, (untested) code to add support for
> +Emerson DS1200 power modules might look as follows.
> +
> +static struct pmbus_driver_info ds1200_info = {
> +	.pages = 1,
> +	/* Note: All other sensors are in linear mode */
> +	.direct[PSC_VOLTAGE_OUT] = true,
> +	.direct[PSC_TEMPERATURE] = true,
> +	.direct[PSC_CURRENT_OUT] = true,
> +	.m[PSC_VOLTAGE_IN] = 1,
> +	.b[PSC_VOLTAGE_IN] = 0,
> +	.R[PSC_VOLTAGE_IN] = 3,
> +	.m[PSC_VOLTAGE_OUT] = 1,
> +	.b[PSC_VOLTAGE_OUT] = 0,
> +	.R[PSC_VOLTAGE_OUT] = 3,
> +	.m[PSC_TEMPERATURE] = 1,
> +	.b[PSC_TEMPERATURE] = 0,
> +	.R[PSC_TEMPERATURE] = 3,
> +	.func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN | PMBUS_HAVE_STATUS_INPUT
> +		   | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
> +		   | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
> +		   | PMBUS_HAVE_PIN | PMBUS_HAVE_POUT
> +		   | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP
> +		   | PMBUS_HAVE_FAN12 | PMBUS_HAVE_STATUS_FAN12,
> +};
> +
> +static int ds1200_probe(struct i2c_client *client,
> +			const struct i2c_device_id *id)
> +{
> +	return pmbus_do_probe(client, id, &ds1200_info);
> +}
> +
> +static int ds1200_remove(struct i2c_client *client)
> +{
> +	return pmbus_do_remove(client);
> +}
> +
> +static const struct i2c_device_id ds1200_id[] = {
> +	{"ds1200", 0},
> +	{}
> +};
> +
> +MODULE_DEVICE_TABLE(i2c, ds1200_id);
> +
> +/* This is the driver that will be inserted */
> +static struct i2c_driver ds1200_driver = {
> +	.driver = {
> +		   .name = "ds1200",
> +		   },
> +	.probe = ds1200_probe,
> +	.remove = ds1200_remove,
> +	.id_table = ds1200_id,
> +};
> +
> +static int __init ds1200_init(void)
> +{
> +	return i2c_add_driver(&ds1200_driver);
> +}
> +
> +static void __exit ds1200_exit(void)
> +{
> +	i2c_del_driver(&ds1200_driver);
> +}
> +
> +
> +Sysfs entries
> +-------------
> +
> +When probing the chip, the driver identifies which PMBus registers are
> +supported, and determines available sensors from this information.
> +Attribute files only exist if respective sensors are suported by the chip.
> +Labels are provided to inform the user about the sensor associated with
> +a given sysfs entry.
> +
> +The following attributes are supported. Limits are read-write; all other
> +attributes are read-only.
> +
> +inX_input		Measured voltage. From READ_VIN or READ_VOUT register.
> +inX_min			Minumum Voltage.
> +			From VIN_UV_WARN_LIMIT or VOUT_UV_WARN_LIMIT register.
> +inX_max			Maximum voltage.
> +			From VIN_OV_WARN_LIMIT or VOUT_OV_WARN_LIMIT register.
> +inX_lcrit		Critical minumum Voltage.
> +			From VIN_UV_FAULT_LIMIT or VOUT_UV_FAULT_LIMIT register.
> +inX_crit		Critical maximum voltage.
> +			From VIN_OV_FAULT_LIMIT or VOUT_OV_FAULT_LIMIT register.
> +inX_min_alarm		Voltage low alarm. From VOLTAGE_UV_WARNING status.
> +inX_max_alarm		Voltage high alarm. From VOLTAGE_OV_WARNING status.
> +inX_lcrit_alarm		Voltage critical low alarm.
> +			From VOLTAGE_UV_FAULT status.
> +inX_crit_alarm		Voltage critical high alarm.
> +			From VOLTAGE_OV_FAULT status.
> +inX_label		"vin", "vcap", or "voutY"
> +
> +currX_input		Measured current. From READ_IIN or READ_IOUT register.
> +currX_max		Maximum current.
> +			From IIN_OC_WARN_LIMIT or IOUT_OC_WARN_LIMIT register.
> +currX_lcrit		Critical minumum output current.
> +			From IOUT_UC_FAULT_LIMIT register.
> +currX_crit		Critical maximum current.
> +			From IIN_OC_FAULT_LIMIT or IOUT_OC_FAULT_LIMIT register.
> +currX_alarm		Current high alarm.
> +			From IIN_OC_WARNING or IOUT_OC_WARNING status.
> +currX_lcrit_alarm	Output current critical low alarm.
> +			From IOUT_UC_FAULT status.
> +currX_crit_alarm	Current critical high alarm.
> +			From IIN_OC_FAULT or IOUT_OC_FAULT status.
> +currX_label		"iin" or "vinY"
> +
> +powerX_input		Measured power. From READ_PIN or READ_POUT register.
> +powerX_cap		Output power cap. From POUT_MAX register.
> +powerX_max		Power limit. From PIN_OP_WARN_LIMIT or
> +			POUT_OP_WARN_LIMIT register.
> +powerX_crit		Critical output power limit.
> +			From POUT_OP_FAULT_LIMIT register.
> +powerX_alarm		Power high alarm.
> +			From PIN_OP_WARNING or POUT_OP_WARNING status.
> +powerX_crit_alarm	Output power critical high alarm.
> +			From POUT_OP_FAULT status.
> +powerX_label		"pin" or "poutY"
> +
> +tempX_input		Measured tempererature.
> +			From READ_TEMPERATURE_X register.
> +tempX_min		Mimimum tempererature. From UT_WARN_LIMIT register.
> +tempX_max		Maximum tempererature. From OT_WARN_LIMIT register.
> +tempX_lcrit		Critical low tempererature.
> +			From UT_FAULT_LIMIT register.
> +tempX_crit		Critical high tempererature.
> +			From OT_FAULT_LIMIT register.
> +tempX_min_alarm		Chip temperature low alarm. Set by comparing
> +			READ_TEMPERATURE_X with UT_WARN_LIMIT if
> +			TEMP_UT_WARNING status is set.
> +tempX_max_alarm		Chip temperature high alarm. Set by comparing
> +			READ_TEMPERATURE_X with OT_WARN_LIMIT if
> +			TEMP_OT_WARNING status is set.
> +tempX_lcrit_alarm	Chip temperature critical low alarm. Set by comparing
> +			READ_TEMPERATURE_X with UT_FAULT_LIMIT if
> +			TEMP_UT_FAULT status is set.
> +tempX_crit_alarm	Chip temperature critical high alarm. Set by comparing
> +			READ_TEMPERATURE_X with OT_FAULT_LIMIT if
> +			TEMP_OT_FAULT status is set.