827df0571f
Until now the "channel" number is identical to how the channel is identified inside the (FIFO) registers. In our case we have eight channels and the hardware also has eight inputs. However, there are two special inputs: - channel 6 can select between the SAR_ADC_CH6 pad and the chip's internal temperature sensor - channel 7 can select between SAR_ADC_CH7 and VSS, VDD / 4, VDD / 2, VDD * 3 / 4 and VDD. When programming the registers to read for example the temperature sensor we have to select FIFO channel 6, set the correct bit which muxes channel 6 to the temperature sensor and then start the ADC measurement for channel 6 as usual. When we add support for the temperature sensor the driver has to know about that it has to use FIFO channel 6 to measure using the chip's internal temperature sensor. However, in that case the iio_chan_spec channel will not be 6 because this is already used for the SAR_ADC_CH6 pad input. Thus we use iio_chan_spec's address field to store the FIFO channel number for each channel. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> |
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| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.