# GPIO Interrupt **URL:** \ **Category:** Jetson TX2\ **Created:** [November 6, 2017, 8:20am UTC](https://forums.developer.nvidia.com/t/gpio-interrupt/54897 "2017-11-06T08:20:35Z")\ **Posts on this page:** 13\ **Page:** 1
**Author:** ![spke12](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@spke12](https://forums.developer.nvidia.com/u/spke12)\ **Post date:** [November 6, 2017, 8:20am UTC](https://forums.developer.nvidia.com/t/gpio-interrupt/54897/1 "2017-11-06T08:20:35Z")
Hi, I’m a beginner to jetson tx2. I am reading signal from GPIO pin to detect edges in signal. I want to go with interrupts but I do not have any idea to lead it with c language. can any on e help me to go with interrupt in GPIO? ---
**Author:** ![JerryChang](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/jerrychang/32/14043_2.png) [@JerryChang](https://forums.developer.nvidia.com/u/JerryChang)\ **Post date:** [November 6, 2017, 8:57am UTC](https://forums.developer.nvidia.com/t/gpio-interrupt/54897/2 "2017-11-06T08:57:48Z")
hello sanjeewaapp, you’re able to access the kernel sources via Jetson Download Center. [url][https://developer.nvidia.com/embedded/dlc/l4t-sources-28-1[/url]](https://developer.nvidia.com/embedded/dlc/l4t-sources-28-1%5B/url%5D) please check the tegra\_gpio\_readl() functions for more details. thanks ---
**Author:** ![spke12](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@spke12](https://forums.developer.nvidia.com/u/spke12)\ **Post date:** [November 6, 2017, 9:31am UTC](https://forums.developer.nvidia.com/t/gpio-interrupt/54897/3 "2017-11-06T09:31:22Z")
Hi Jerry, Thanks for your reply. I’ll refer it. Where is it located? ---
**Author:** ![JerryChang](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/jerrychang/32/14043_2.png) [@JerryChang](https://forums.developer.nvidia.com/u/JerryChang)\ **Post date:** [November 6, 2017, 10:34am UTC](https://forums.developer.nvidia.com/t/gpio-interrupt/54897/4 "2017-11-06T10:34:51Z")
hello sanjeewaapp, you could check below for example, R28.1\_sources/kernel/kernel-4.4/drivers/gpio-tegra.c ---
**Author:** ![spke12](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@spke12](https://forums.developer.nvidia.com/u/spke12)\ **Post date:** [November 6, 2017, 10:36am UTC](https://forums.developer.nvidia.com/t/gpio-interrupt/54897/5 "2017-11-06T10:36:47Z")
Hi Jerry, I got. Can I use it directly? Thanks ---
**Author:** ![kayccc](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/kayccc/32/14043_2.png) [@kayccc](https://forums.developer.nvidia.com/u/kayccc)\ **Post date:** [November 8, 2017, 8:48am UTC](https://forums.developer.nvidia.com/t/gpio-interrupt/54897/6 "2017-11-08T08:48:53Z")
Hi sanjeewaapp, Have you tried the tegra\_gpio\_readl() function to get the result you want? Any further support required? Thanks ---
**Author:** ![spke12](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@spke12](https://forums.developer.nvidia.com/u/spke12)\ **Post date:** [November 8, 2017, 12:57pm UTC](https://forums.developer.nvidia.com/t/gpio-interrupt/54897/7 "2017-11-08T12:57:08Z")
Hi kayccc, I could not be able to figure it out. still I am searching a way to do it. Now I am looking to develop kernel module that can be used to interface GPIO. can you help me to figure it out readl() function? Thanks ---
**Author:** ![JerryChang](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/jerrychang/32/14043_2.png) [@JerryChang](https://forums.developer.nvidia.com/u/JerryChang)\ **Post date:** [November 23, 2017, 8:27am UTC](https://forums.developer.nvidia.com/t/gpio-interrupt/54897/8 "2017-11-23T08:27:39Z")
hello spke12, you can refer to the tegra\_gpio\_readl() function to read the pin status, and implement your own interrupt function to handle that. thanks ---
**Author:** ![spke12](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@spke12](https://forums.developer.nvidia.com/u/spke12)\ **Post date:** [November 24, 2017, 5:20am UTC](https://forums.developer.nvidia.com/t/gpio-interrupt/54897/9 "2017-11-24T05:20:58Z")
hello Jerry, You are saying that I have to implement my own kernel module aren’t you? Thanks ---
**Author:** ![JerryChang](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/jerrychang/32/14043_2.png) [@JerryChang](https://forums.developer.nvidia.com/u/JerryChang)\ **Post date:** [December 1, 2017, 3:13am UTC](https://forums.developer.nvidia.com/t/gpio-interrupt/54897/10 "2017-12-01T03:13:27Z")
hello spke12, yes, please refer to that function and implement your own interrupt function. thanks ---
**Author:** ![wuyankun1986](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@wuyankun1986](https://forums.developer.nvidia.com/u/wuyankun1986)\ **Post date:** [December 1, 2017, 12:35pm UTC](https://forums.developer.nvidia.com/t/gpio-interrupt/54897/11 "2017-12-01T12:35:57Z")
Hello JerryChang, we want to use the gpio pin as interrupt, just like spke12’s case. I had saw the source code: R28.1\_sources/kernel/kernel-4.4/drivers/goio/gpio-tegra.c And I also find some information in the /proc/interrupts. 256 tegra-gpio 125 Edge sdhci.cd I had read the sourcecode: R28.1\_sources/kernel/kernel-4.4/drivers/mmc/host/sdhci-tegra.c the cd detect pin is GPIO3\_PP.05 and the device tree is cd-gpios = \<&tegra\_main\_gpio TEGRA\_MAIN\_GPIO(P,5) 0\> but in the sourcecode of sdhci-tegra.c a.plat-\>cd\_gpio = of\_get\_named\_gpio(np, “cd-gpios”, 0); b.gpio\_is\_valid(plat-\>cd\_gpio) c.tegra\_host-\>cd\_irq = gpio\_to\_irq(plat-\>cd\_gpio); d.disable\_irq\_wake(tegra\_host-\>cd\_irq); e.enable\_irq\_wake(tegra\_host-\>cd\_irq); then I try to find something like “request\_irq or request\_gpio\_irq” there is nothing here. I don’t understand, how to bind the irq number to the interrupt respond server. thanks. ---
**Author:** ![JerryChang](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/jerrychang/32/14043_2.png) [@JerryChang](https://forums.developer.nvidia.com/u/JerryChang)\ **Post date:** [December 5, 2017, 8:52am UTC](https://forums.developer.nvidia.com/t/gpio-interrupt/54897/12 "2017-12-05T08:52:23Z")
hello wuyankun1986, > > _I don’t understand, how to bind the irq number to the interrupt respond server._ > > please refer to this function for more details, > > thanks r28.1\_sources/kernel/kernel-4.4/drivers/gpio/gpiolib.c ```auto int gpiod_to_irq(const struct gpio_desc *desc) { struct gpio_chip *chip; int offset; if (!desc) return -EINVAL; chip = desc->chip; offset = gpio_chip_hwgpio(desc); return chip->to_irq ? chip->to_irq(chip, offset) : -ENXIO; } EXPORT_SYMBOL_GPL(gpiod_to_irq); ``` ---
**Author:** ![nadeemm](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/nadeemm/32/367020_2.png) [@nadeemm](https://forums.developer.nvidia.com/u/nadeemm)\ **Post date:** [October 18, 2021, 6:27pm UTC](https://forums.developer.nvidia.com/t/gpio-interrupt/54897/13 "2021-10-18T18:27:35Z")
Closed on October 18, 2021, 6:27pm UTC