Re: [RFC PATCH 1/2] serial: core: Move tty and serdev to be children of serial core port device

From: Johan Hovold
Date: Wed Oct 25 2023 - 03:34:05 EST


On Wed, Oct 25, 2023 at 09:51:52AM +0300, Tony Lindgren wrote:
> * Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> [231024 14:01]:

> > > > What does this change the sysfs tree to look like?

> Here's the diff of the same command before and after:
>
> --- /tmp/before 2023-10-25 09:45:12.197283690 +0300
> +++ /tmp/after 2023-10-25 09:43:30.681797899 +0300
> @@ -1,7 +1,9 @@
> # find /sys -name tty
> /sys/class/tty
> /sys/class/tty/tty
> -/sys/devices/pnp0/00:04/tty
> -/sys/devices/platform/serial8250/tty
> +/sys/devices/pnp0/00:04/00:04:0/00:04:0.0/tty
> +/sys/devices/platform/serial8250/serial8250:0/serial8250:0.3/tty
> +/sys/devices/platform/serial8250/serial8250:0/serial8250:0.1/tty
> +/sys/devices/platform/serial8250/serial8250:0/serial8250:0.2/tty
> /sys/devices/virtual/tty
> /sys/devices/virtual/tty/tty

Your diff is missing the actual tty devices. 'tty' is just the class
directory.

And can you post the equivalent diff for serdev as well for completeness?

> There are multiple ports claimed by serial8250. So I think the new sysfs
> output is correct showing more ttys. If there's some reason why serial8250
> should only have one tty and this output is not correct let me know too..

There should not be more class devices, you've just moved them and thus
there are more class directories (with one device per directory).

Johan