2 changes: 1 addition & 1 deletion 2 Documentation/userspace-api/gpio/gpio-v2-get-line-ioctl.rst Original file line numberDiff line numberDiff line change @@ -81,7 +81,7 @@ Only one event clock flag, ``GPIO_V2_LINE_FLAG_EVENT_CLOCK_xxx``, may be set. If none are set then th...
if (atomic_cmpxchg(&cdata..., version) == 0) return 0; // we were first! return -EPERM; // somebody has changed the version before us! > > > > Shouldn't be rather > > > > > > > > if (atomic_cmpxchg() == 0) { > > > > if (atomic_read() != version) > > > > ...
> > if (atomic_cmpxchg(&cdata..., version) == 0) > > return 0; // we were first! > > return -EPERM; // somebody has changed the version before us! > > > > Which can fail if two callers are requesting the same version - in a > race the second one will get a fail - ...
If the registration code detects that a line is already registered, it attempts to make the line name unique by prefixing it with the chip name. Tested on a Pi5, and a Pi Zero W. Improve registration to handle vagaries of how the Linux kernel handles … 77aa312 codecov bot commented...
在引擎盖下面,libgpiod打开内核为行提供的fd,然后调用ioctl(fd, GPIO_V2_LINE_SET_VALUES_IOCTL, ...)。我的问题是:ioctl()调用在理论上是否一般是阻塞的?例如,首先请求行也涉及到芯片fd上的ioctl()。I2C ioctl()s呢?如果它是阻塞的,是行结构(line-&g 浏览0提问于2021-07-01得票数 5 回答...
1; lreq.config.num_attrs = 1; lreq.config.attrs[0].attr.id = GPIO_V2_LINE_ATTR_ID_DEBOUNCE; lreq.config.attrs[0].attr.debounce_period_us = 100000; lreq.config.attrs[0].mask = (1 << 0); strcpy(lreq.consumer, "GPIOV2"); ret = ioctl(fd, GPIO_V2_GET_LINE_IOCTL, &lreq...
處理IOCTL_GPIO_COMMIT_FUNCTION_CONFIG_PINS 要求用戶端透過開啟控制代碼成功保留 MsftFunctionConfig 資源後,可以傳送 IOCTL_GPIO_COMMIT_FUNCTION_CONFIG_PINS 來要求伺服器執行實際的硬體多工處理作業。 當伺服器收到 IOCTL_GPIO_COMMIT_FUNCTION_CONFIG_PINS 時,應該對針腳清單中的每個針腳...
ret=ioctl(fd, GPIO_GET_LINEEVENT_IOCTL,&req); if(ret) { printf("ERROR: ioctl get line event ret=%d\n", ret); return-1; } /* set event fd nonbloack read */ fd_in=req.fd; flags=fcntl(fd_in, F_GETFL); flags|=O_NONBLOCK; ...
即当将行配置为输出时），必须使用request->config.attrs（request是一个gpio_v2_line_request结构指针...
应用程序在打开设备文件后,需要调用 ioctl 来获取 GPIO 的默认工作模式或设置 GPIO 的工作模式。当应用程序读取相应 GPIO 引脚的设备文件时,需要将至少一个 Byte 大小的缓冲传递给底层的驱动,驱动程序将判断当前操作的 GPIO 是否处于输入模式;如果处于输入模式则读取 GPIO 引脚的电平,并返回 GPIO 状态给应用程序 —...