b3689e1441
This makes use of the regmap API to read and write the configuration registers. This simplifies code quite a bit and makes it safer (previously, it was easy to write a bad value to the config registers which causes the chip to lock up and need to be reset). This chip has multiple modes of operation. In normal mode, we do not use regmap since there is no addressing - data is just bitshifted out during the SPI read. In config mode, we use regmap since it requires writing the address (with read/write flag) before reading and writing. We don't use the lock provided by the regmap because we need to also synchronize with the normal mode SPI reads and with the various GPIOs. There is also a quirk when reading registers (other than the fault register). If the address/data bit is set in the value read, then it indicates there is a configuration parity error and the data is not valid. Previously, this was checked in a few places, but not consistently. Now, we always check it in the regmap read function. Signed-off-by: David Lechner <dlechner@baylibre.com> Link: https://lore.kernel.org/r/20230929-ad2s1210-mainline-v3-10-fa4364281745@baylibre.com Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
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.
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.