| // Copyright 2020 The Fuchsia Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| @available(added=HEAD) |
| library fuchsia.hardware.gpio; |
| |
| using zx; |
| |
| /// Maximum length of the GPIO name. |
| const MAX_GPIO_NAME_LEN uint32 = 256; |
| |
| /// Flags for `ConfigIn`. |
| type GpioFlags = strict enum : uint32 { |
| PULL_DOWN = 0x0; |
| PULL_UP = 0x1; |
| NO_PULL = 0x2; |
| }; |
| |
| /// Values for `SetPolarity`. |
| type GpioPolarity = strict enum : uint32 { |
| LOW = 0x0; |
| HIGH = 0x1; |
| }; |
| |
| closed protocol Gpio { |
| /// Get the pin of a GPIO |
| strict GetPin() -> (struct { |
| pin uint32; |
| }) error zx.Status; |
| |
| /// Get the name of a GPIO. |
| strict GetName() -> (struct { |
| name string:MAX_GPIO_NAME_LEN; |
| }) error zx.Status; |
| |
| /// Configures a GPIO for input. |
| strict ConfigIn(struct { |
| flags GpioFlags; |
| }) -> () error zx.Status; |
| |
| /// Configures a GPIO for output. |
| strict ConfigOut(struct { |
| initial_value uint8; |
| }) -> () error zx.Status; |
| |
| /// Configures the GPIO pin for an alternate function (I2C, SPI, etc) |
| /// the interpretation of "function" is platform dependent. |
| strict SetAltFunction(struct { |
| function uint64; |
| }) -> () error zx.Status; |
| |
| /// Reads the current value of a GPIO (0 or 1). |
| strict Read() -> (struct { |
| value uint8; |
| }) error zx.Status; |
| |
| /// Sets the current value of the GPIO (any non-zero value maps to 1). |
| strict Write(struct { |
| value uint8; |
| }) -> () error zx.Status; |
| |
| /// Set GPIO polarity. |
| strict SetPolarity(struct { |
| polarity GpioPolarity; |
| }) -> () error zx.Status; |
| |
| /// Sets the drive strength of the GPIO. |
| /// actual_ds_ua is always >= ds_ua. If ds_ua is larger than max value, the drive strength will be set to the max value. |
| /// Return error if unable to set drive strength. actual_ds_ua is not set in this case. |
| strict SetDriveStrength(struct { |
| ds_ua uint64; |
| }) -> (struct { |
| actual_ds_ua uint64; |
| }) error zx.Status; |
| |
| /// Gets the configured drive strength of the GPIO in microamps (ua). |
| strict GetDriveStrength() -> (struct { |
| result_ua uint64; |
| }) error zx.Status; |
| |
| /// Gets an interrupt object pertaining to a particular GPIO pin. `flags` |
| /// is passed as the `options` parameter when |
| /// [creating the interrupt](https://fuchsia.dev/fuchsia-src/reference/syscalls/interrupt_create). |
| strict GetInterrupt(struct { |
| flags uint32; |
| }) -> (resource struct { |
| irq zx.Handle:INTERRUPT; |
| }) error zx.Status; |
| |
| /// Release the interrupt. |
| strict ReleaseInterrupt() -> () error zx.Status; |
| }; |
| |
| closed protocol Device { |
| /// Opens a new session on the device. |
| /// |
| /// At most one session is permitted at one time; the server end will be |
| /// closed with `ZX_ERR_ALREADY_BOUND` if a session already exists. |
| strict OpenSession(resource struct { |
| session server_end:Gpio; |
| }); |
| }; |
| |
| service Service { |
| device client_end:Gpio; |
| }; |