This driver actually does nothing but test pinctrl uclass, and
demonstrate how things work.
To try this driver, uncomment /* #define DEBUG */ in the
drivers/pinctrl/pinctrl-sandbox.c, and debug messages will be
displayed.
DRAM: 128 MiB
sandbox pinmux: group = 1 (serial_a), function = 1 (serial)
Using default environment
In: cros-ec-keyb
Out: lcd
Err: lcd
Net: Net Initialization Skipped
eth0: eth@10002000, eth1: eth@80000000, eth5: eth@90000000
=> i2c dev 0
Setting bus to 0
sandbox pinmux: group = 0 (i2c), function = 0 (i2c)
sandbox pinconf: group = 0 (i2c), param = 3, arg = 1
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Simon Glass <sjg@chromium.org>
This creates a new framework for handling of pin control devices,
i.e. devices that control different aspects of package pins.
This uclass handles pinmuxing and pin configuration; pinmuxing
controls switching among silicon blocks that share certain physical
pins, pin configuration handles electronic properties such as pin-
biasing, load capacitance etc.
This framework can support the same device tree bindings, but if you
do not need full interface support, you can disable some features to
reduce memory foot print. Typically around 1.5KB is necessary to
include full-featured uclass support on ARM board (CONFIG_PINCTRL +
CONFIG_PINCTRL_FULL + CONFIG_PINCTRL_GENERIC + CONFIG_PINCTRL_PINMUX),
for example.
We are often limited on code size for SPL. Besides, we still have
many boards that do not support device tree configuration. The full
pinctrl, which requires OF_CONTROL, does not make sense for those
boards. So, this framework also has a Do-It-Yourself (let's say
simple pinctrl) interface. With CONFIG_PINCTRL_FULL disabled, the
uclass itself provides no systematic mechanism for identifying the
peripheral device, applying pinctrl settings, etc. They must be
done in each low-level driver. In return, you can save much memory
footprint and it might be useful especially for SPL.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Simon Glass <sjg@chromium.org>
