[PATCH 3/4] [v6] pinctrl: qcom: disable GPIO groups with no pins
Stephen Boyd
sboyd at codeaurora.org
Thu Nov 16 18:43:32 PST 2017
On 11/07, Timur Tabi wrote:
> pinctrl-msm only accepts an array of GPIOs from 0 to n-1, and it expects
> each group to support have only one pin (npins == 1).
>
> We can support "sparse" GPIO maps if we allow for some groups to have zero
> pins (npins == 0). These pins are "hidden" from the rest of the driver
> and gpiolib.
>
> A new boolean 'sparse' indicates whether the GPIO map is sparse. If any
> GPIO has an 'npins' value of 0, then 'sparse' must be set to True.
>
> Most access to unavailable GPIOs can be blocked via the gpio_chip.request
> function. The one exception is when gpiochip_add_data() scans all of
If patch 1 is applied is this statement still true?
> the GPIOs without "requesting" them. To cover this case,
s/GPIOs/GPIOs for their direction/ perhaps?
> msm_gpio_get_direction() separately checks if the GPIO is available.
>
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