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* pinctrl: Add the concept of peripheral IDsSimon Glass2015-09-021-9/+31
| | | | | | | | | | | | | | | | | | | | | | | | | My original pinctrl patch operating using a peripheral ID enum. This was shared between pinmux and clock and provides an easy way to specify a device that needs to be controlled, even it is does not (yet) have a driver within driver model. Masahiro's new simple pinctrl gets around this by providing a set_state_simple() pinctrl method. By passing a device to that call the peripheral ID becomes unnecessary. If the driver needs it, it can calculate it itself and use it internally. However this does not solve the problem for peripheral clocks. The 'pure' solution would be to pass a driver to the clock uclass also. But this requires that all devices should have a driver, and a struct udevide. Also a key optimisation of the clock uclass is allowing a peripheral clock to be set even when there is no device for that clock. There may be a better way to achive the same goal, but for now it seems expedient to add in peripheral ID to the pinctrl uclass. Two methods are added - one to get the peripheral ID and one to select it. The existing set_state_simple() is effectively the union of these. Signed-off-by: Simon Glass <sjg@chromium.org>
* pinctrl: add pin control uclass supportMasahiro Yamada2015-08-311-0/+240
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>
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