On Thu, Oct 19, 2023 at 01:28:08PM +0200, Florian Eckert wrote: > The struct 'tty_struct' has a callback to read the status flags of the tty > if the tty driver provides them. So fare, the data is transferred directly > to userspace with the function 'tty_tiocmget'. This function cannot be > used to evaluate the status line of the tty interface in the ledtrig-tty > trigger. To make this possible, a new function must be added that does > not immediately pass the data on to userspace. > > The new function 'tty_get_tiocm' only returns the status register. > This information can then be processed further in the ledtrig-tty > trigger. Writing changelogs are hard. You are including a lot of information in here that really doesn't need to be, as you are focusing on your specific use case, which is fine, but you are creating a generic function. This can be simpler, how about something like this: There is no in-kernel function to get the status register of a tty device like the TIOCMGET ioctl returns to userspace. Create a new function, tty_get_tiocm(), to obtain the status register that other portions of the kernel can call if they need this information, and move the existing internal tty_tiocmget() function to use this interface. Sound good? The code portion looks fine to me, thanks for doing this. greg k-h
