diff options
Diffstat (limited to 'Documentation/driver-api/gpio')
| -rw-r--r-- | Documentation/driver-api/gpio/consumer.rst | 5 | ||||
| -rw-r--r-- | Documentation/driver-api/gpio/driver.rst | 4 | ||||
| -rw-r--r-- | Documentation/driver-api/gpio/intro.rst | 8 |
3 files changed, 9 insertions, 8 deletions
diff --git a/Documentation/driver-api/gpio/consumer.rst b/Documentation/driver-api/gpio/consumer.rst index 173e4c7b037d..22271c342d92 100644 --- a/Documentation/driver-api/gpio/consumer.rst +++ b/Documentation/driver-api/gpio/consumer.rst @@ -361,12 +361,13 @@ corresponding chip driver. In that case a significantly improved performance can be expected. If simultaneous access is not possible the GPIOs will be accessed sequentially. -The functions take three arguments: +The functions take four arguments: + * array_size - the number of array elements * desc_array - an array of GPIO descriptors * array_info - optional information obtained from gpiod_get_array() * value_bitmap - a bitmap to store the GPIOs' values (get) or - a bitmap of values to assign to the GPIOs (set) + a bitmap of values to assign to the GPIOs (set) The descriptor array can be obtained using the gpiod_get_array() function or one of its variants. If the group of descriptors returned by that function diff --git a/Documentation/driver-api/gpio/driver.rst b/Documentation/driver-api/gpio/driver.rst index 0fb57e298b41..d6b0d779859b 100644 --- a/Documentation/driver-api/gpio/driver.rst +++ b/Documentation/driver-api/gpio/driver.rst @@ -640,8 +640,8 @@ compliance: level and edge IRQs * [1] http://www.spinics.net/lists/linux-omap/msg120425.html -* [2] https://lkml.org/lkml/2015/9/25/494 -* [3] https://lkml.org/lkml/2015/9/25/495 +* [2] https://lore.kernel.org/r/1443209283-20781-2-git-send-email-grygorii.strashko@ti.com +* [3] https://lore.kernel.org/r/1443209283-20781-3-git-send-email-grygorii.strashko@ti.com Requesting self-owned GPIO pins diff --git a/Documentation/driver-api/gpio/intro.rst b/Documentation/driver-api/gpio/intro.rst index 74591489d0b5..94dd7185e76e 100644 --- a/Documentation/driver-api/gpio/intro.rst +++ b/Documentation/driver-api/gpio/intro.rst @@ -106,11 +106,11 @@ don't. When you need open drain signaling but your hardware doesn't directly support it, there's a common idiom you can use to emulate it with any GPIO pin that can be used as either an input or an output: - LOW: gpiod_direction_output(gpio, 0) ... this drives the signal and overrides - the pullup. + **LOW**: ``gpiod_direction_output(gpio, 0)`` ... this drives the signal and + overrides the pullup. - HIGH: gpiod_direction_input(gpio) ... this turns off the output, so the pullup - (or some other device) controls the signal. + **HIGH**: ``gpiod_direction_input(gpio)`` ... this turns off the output, so + the pullup (or some other device) controls the signal. The same logic can be applied to emulate open source signaling, by driving the high signal and configuring the GPIO as input for low. This open drain/open |