Lines Matching +full:irq +full:- +full:active +full:- +full:high
6 it describes the new descriptor-based interface. For a description of the
7 deprecated integer-based GPIO interface please refer to legacy.rst.
23 - Simple compile coverage with e.g. COMPILE_TEST - it does not matter that
27 - Truly optional GPIOLIB support - where the driver does not really make use
28 of the GPIOs on certain compile-time configurations for certain systems, but
29 will use it under other compile-time configurations. In this case the
33 All the functions that work with the descriptor-based GPIO interface are
43 With the descriptor-based interface, GPIOs are identified with an opaque,
44 non-forgeable handler that must be obtained through a call to one of the
60 see Documentation/driver-api/gpio/board.rst
76 whether the line is configured active high or active low (see
85 with IS_ERR() (they will never return a NULL pointer). -ENOENT will be returned
92 instead of -ENOENT if no GPIO has been assigned to the requested function::
106 -ENOSYS return codes. System integrators should however be careful to enable
125 The following function returns NULL instead of -ENOENT if no GPIOs have been
132 Device-managed variants of these functions are also defined::
171 The device-managed variants are, unsurprisingly::
182 -----------------
184 direction-setting flags have been given to gpiod_get*(), this is done by
193 for spinlock-safe GPIOs it is OK to use them before tasking is enabled, as part
210 Spinlock-Safe GPIO Access
211 -------------------------
213 don't need to sleep, and can safely be done from inside hard (non-threaded) IRQ
221 The values are boolean, zero for low, nonzero for high. When reading the value
224 open-drain signaling and output latencies.
234 --------------------------
238 sleeping, which can't be done from inside IRQ handlers.
251 IRQ handler, and those accessors must be used instead of spinlock-safe
256 spinlock-safe calls.
261 The active low and open drain semantics
262 ---------------------------------------
265 the *logical* value. With this they take the active low property into account.
266 This means that they check whether the GPIO is configured to be active low,
271 actively drive their output high (open drain) or low (open source), they just
272 switch their output to a high impedance value. The consumer should not need to
276 parameter "value" as "asserted" ("1") or "de-asserted" ("0"). The physical line
279 As an example, if the active low property for a dedicated GPIO is set, and the
287 gpiod_set_raw_value(desc, 1); don't care high
288 gpiod_set_value(desc, 0); default (active high) low
289 gpiod_set_value(desc, 1); default (active high) high
290 gpiod_set_value(desc, 0); active low high
291 gpiod_set_value(desc, 1); active low low
293 gpiod_set_value(desc, 1); open drain high impedance
294 gpiod_set_value(desc, 0); open source high impedance
295 gpiod_set_value(desc, 1); open source high
298 but it should be avoided as much as possible, especially by system-agnostic drivers
304 -------------------------
309 The following set of calls ignore the active-low or open drain property of a GPIO and
318 The active low state of a GPIO can also be queried and toggled using the
329 -------------------------------------------------
374 * array_size - the number of array elements
375 * desc_array - an array of GPIO descriptors
376 * array_info - optional information obtained from gpiod_get_array()
377 * value_bitmap - a bitmap to store the GPIOs' values (get) or
386 gpiod_set_array_value(my_gpio_descs->ndescs, my_gpio_descs->desc,
387 my_gpio_descs->info, my_gpio_value_bitmap);
413 --------------------
414 GPIO lines can quite often be used as IRQs. You can get the IRQ number
419 It will return an IRQ number, or a negative errno code if the mapping can't be
420 done (most likely because that particular GPIO cannot be used as IRQ). It is an
422 gpiod_direction_input(), or to use an IRQ number that didn't originally come
425 Non-error values returned from gpiod_to_irq() can be passed to request_irq() or
426 free_irq(). They will often be stored into IRQ resources for platform devices,
427 by the board-specific initialization code. Note that IRQ trigger options are
428 part of the IRQ interface, e.g. IRQF_TRIGGER_FALLING, as are system wakeup
447 For details refer to Documentation/firmware-guide/acpi/gpio-properties.rst
453 integer-based interface. It is strongly recommended to update these to the new
456 and vice-versa::