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Diffstat (limited to 'Documentation/driver-api/gpio/legacy.rst')
| -rw-r--r-- | Documentation/driver-api/gpio/legacy.rst | 17 |
1 files changed, 0 insertions, 17 deletions
diff --git a/Documentation/driver-api/gpio/legacy.rst b/Documentation/driver-api/gpio/legacy.rst index e17910cc3271..a0559d93efd1 100644 --- a/Documentation/driver-api/gpio/legacy.rst +++ b/Documentation/driver-api/gpio/legacy.rst @@ -387,9 +387,6 @@ map between them using calls like:: /* map GPIO numbers to IRQ numbers */ int gpio_to_irq(unsigned gpio); - /* map IRQ numbers to GPIO numbers (avoid using this) */ - int irq_to_gpio(unsigned irq); - Those return either the corresponding number in the other namespace, or else a negative errno code if the mapping can't be done. (For example, some GPIOs can't be used as IRQs.) It is an unchecked error to use a GPIO @@ -405,11 +402,6 @@ devices, by the board-specific initialization code. Note that IRQ trigger options are part of the IRQ interface, e.g. IRQF_TRIGGER_FALLING, as are system wakeup capabilities. -Non-error values returned from irq_to_gpio() would most commonly be used -with gpio_get_value(), for example to initialize or update driver state -when the IRQ is edge-triggered. Note that some platforms don't support -this reverse mapping, so you should avoid using it. - Emulating Open Drain Signals ---------------------------- @@ -735,10 +727,6 @@ requested using gpio_request():: /* reverse gpio_export() */ void gpio_unexport(); - /* create a sysfs link to an exported GPIO node */ - int gpio_export_link(struct device *dev, const char *name, - unsigned gpio) - After a kernel driver requests a GPIO, it may only be made available in the sysfs interface by gpio_export(). The driver can control whether the signal direction may change. This helps drivers prevent userspace code @@ -748,11 +736,6 @@ This explicit exporting can help with debugging (by making some kinds of experiments easier), or can provide an always-there interface that's suitable for documenting as part of a board support package. -After the GPIO has been exported, gpio_export_link() allows creating -symlinks from elsewhere in sysfs to the GPIO sysfs node. Drivers can -use this to provide the interface under their own device in sysfs with -a descriptive name. - API Reference ============= |