iio: ABI: add ABI file for the LTC2688 DAC

Define the sysfs interface for toggle or dither capable channels. Dither
capable channels will have the extended interface:

 * out_voltageY_dither_en
 * out_voltageY_dither_raw
 * out_voltageY_dither_offset
 * out_voltageY_dither_raw_available
 * out_voltageY_dither_frequency
 * out_voltageY_dither_frequency_available
 * out_voltageY_dither_phase
 * out_voltageY_dither_phase_available

Toggle enabled channels will have:

 * out_voltageY_toggle_en
 * out_voltageY_raw0
 * out_voltageY_raw1
 * out_voltageY_symbol

The common interface present in all channels is:

 * out_voltageY_raw (not present in toggle enabled channels)
 * out_voltageY_raw_available
 * out_voltageY_powerdown
 * out_voltageY_scale
 * out_voltageY_offset
 * out_voltageY_calibbias
 * out_voltageY_calibscale

Signed-off-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20220225130129.69-3-nuno.sa@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
Nuno Sá 2022-02-25 14:01:28 +01:00 committed by Jonathan Cameron
parent 832cb9eeb9
commit 52302f87d0
2 changed files with 87 additions and 0 deletions

View File

@ -0,0 +1,86 @@
What: /sys/bus/iio/devices/iio:deviceX/out_voltageY_dither_en
KernelVersion: 5.18
Contact: linux-iio@vger.kernel.org
Description:
Dither enable. Write 1 to enable dither or 0 to disable it. This is useful
for changing the dither parameters. They way it should be done is:
- disable dither operation;
- change dither parameters (eg: frequency, phase...);
- enabled dither operation
What: /sys/bus/iio/devices/iio:deviceX/out_voltageY_dither_raw
KernelVersion: 5.18
Contact: linux-iio@vger.kernel.org
Description:
This raw, unscaled value refers to the dither signal amplitude.
The same scale as in out_voltageY_raw applies. However, the
offset might be different as it's always 0 for this attribute.
What: /sys/bus/iio/devices/iio:deviceX/out_voltageY_dither_raw_available
KernelVersion: 5.18
Contact: linux-iio@vger.kernel.org
Description:
Available range for dither raw amplitude values.
What: /sys/bus/iio/devices/iio:deviceX/out_voltageY_dither_offset
KernelVersion: 5.18
Contact: linux-iio@vger.kernel.org
Description:
Offset applied to out_voltageY_dither_raw. Read only attribute
always set to 0.
What: /sys/bus/iio/devices/iio:deviceX/out_voltageY_dither_frequency
KernelVersion: 5.18
Contact: linux-iio@vger.kernel.org
Description:
Sets the dither signal frequency. Units are in Hz.
What: /sys/bus/iio/devices/iio:deviceX/out_voltageY_dither_frequency_available
KernelVersion: 5.18
Contact: linux-iio@vger.kernel.org
Description:
Returns the available values for the dither frequency.
What: /sys/bus/iio/devices/iio:deviceX/out_voltageY_dither_phase
KernelVersion: 5.18
Contact: linux-iio@vger.kernel.org
Description:
Sets the dither signal phase. Units are in Radians.
What: /sys/bus/iio/devices/iio:deviceX/out_voltageY_dither_phase_available
KernelVersion: 5.18
Contact: linux-iio@vger.kernel.org
Description:
Returns the available values for the dither phase.
What: /sys/bus/iio/devices/iio:deviceX/out_voltageY_toggle_en
KernelVersion: 5.18
Contact: linux-iio@vger.kernel.org
Description:
Toggle enable. Write 1 to enable toggle or 0 to disable it. This is
useful when one wants to change the DAC output codes. The way it should
be done is:
- disable toggle operation;
- change out_voltageY_raw0 and out_voltageY_raw1;
- enable toggle operation.
What: /sys/bus/iio/devices/iio:deviceX/out_voltageY_raw0
What: /sys/bus/iio/devices/iio:deviceX/out_voltageY_raw1
KernelVersion: 5.18
Contact: linux-iio@vger.kernel.org
Description:
It has the same meaning as out_voltageY_raw. This attribute is
specific to toggle enabled channels and refers to the DAC output
code in INPUT_A (_raw0) and INPUT_B (_raw1). The same scale and offset
as in out_voltageY_raw applies.
What: /sys/bus/iio/devices/iio:deviceX/out_voltageY_symbol
KernelVersion: 5.18
Contact: linux-iio@vger.kernel.org
Description:
Performs a SW toggle. This attribute is specific to toggle
enabled channels and allows to toggle between out_voltageY_raw0
and out_voltageY_raw1 through software. Writing 0 will select
out_voltageY_raw0 while 1 selects out_voltageY_raw1.

View File

@ -11322,6 +11322,7 @@ M: Nuno Sá <nuno.sa@analog.com>
L: linux-iio@vger.kernel.org
S: Supported
W: http://ez.analog.com/community/linux-device-drivers
F: Documentation/ABI/testing/sysfs-bus-iio-dac-ltc2688
F: drivers/iio/dac/ltc2688.c
LTC2947 HARDWARE MONITOR DRIVER