diff options
author | Janusz Krzysztofik <jmkrzyszt@gmail.com> | 2018-09-06 00:50:06 +0300 |
---|---|---|
committer | Linus Walleij <linus.walleij@linaro.org> | 2018-09-13 12:16:12 +0300 |
commit | bf9346f5d47b4506aafbc384dfb5796b0adc3f8d (patch) | |
tree | 36059c2536ba006875029d5edbe9615d98dc3180 /include/linux/gpio/consumer.h | |
parent | b9762bebc6332b40c33e03dea03e30fa12d9e3ed (diff) | |
download | linux-bf9346f5d47b4506aafbc384dfb5796b0adc3f8d.tar.xz |
gpiolib: Identify arrays matching GPIO hardware
Certain GPIO array lookup results may map directly to GPIO pins of a
single GPIO chip in hardware order. If that condition is recognized
and handled efficiently, significant performance gain of get/set array
functions may be possible.
While processing a request for an array of GPIO descriptors, identify
those which represent corresponding pins of a single GPIO chip. Skip
over pins which require open source or open drain special processing.
Moreover, identify pins which require inversion. Pass a pointer to
that information with the array to the caller so it can benefit from
enhanced performance as soon as get/set array functions can accept and
make efficient use of it.
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'include/linux/gpio/consumer.h')
-rw-r--r-- | include/linux/gpio/consumer.h | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/include/linux/gpio/consumer.h b/include/linux/gpio/consumer.h index 2b0389f0bec4..0ffd71c0a77c 100644 --- a/include/linux/gpio/consumer.h +++ b/include/linux/gpio/consumer.h @@ -18,10 +18,19 @@ struct device; struct gpio_desc; /** + * Opaque descriptor for a structure of GPIO array attributes. This structure + * is attached to struct gpiod_descs obtained from gpiod_get_array() and can be + * passed back to get/set array functions in order to activate fast processing + * path if applicable. + */ +struct gpio_array; + +/** * Struct containing an array of descriptors that can be obtained using * gpiod_get_array(). */ struct gpio_descs { + struct gpio_array *info; unsigned int ndescs; struct gpio_desc *desc[]; }; |