Messages in this thread | | | Date | Thu, 17 Apr 2014 11:47:54 -0500 | From | Timur Tabi <> | Subject | Re: [PATCH v3 1/1] pinctrl: add Intel BayTrail GPIO/pinctrl support |
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On 04/15/2014 05:01 AM, Mathias Nyman wrote: >> >> This device will only be used on an ACPI system, right? And isn't ACPI >> supposed to hide all the pinctrl programming from the OS? I thought >> that was the whole point behind ACPI and the reason why ARM64 isn't >> going to use device trees. >> > > This was my starting point as well, and the driver was initially > submitted as a GPIO driver. But Linus W. suggested pinctrl instead, and > as he's the maintainer of both those subsystem I trust his judgment.
Do you think, for an ACPI pinctrl driver, that we will need to specify any function groups? When I look at the ASL that configures GPIOs, I see only lines like this:
GpioIo (Exclusive, PullDefault, , , , "\\GIO0") {0x1D, 0x1E}
This tells me that ACPI will never use any of the names that are defined. I see that .get_function_name is called on my ACPI system, but I don't see where it is used.
The reason I ask is because I would like to make a "generic" ACPI pinctrl/gpio driver that doesn't specify any pin groups. So if we use the same pinctrl/gpio hardware on multiple SOCs, the only thing that the driver needs from ACPI is the number of pins.
-- Sent by an employee of the Qualcomm Innovation Center, Inc. The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, hosted by the Linux Foundation.
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