On Mon, Apr 24, 2023 at 09:52:44AM +0200, D. Starke wrote: > From: Daniel Starke <daniel.starke@xxxxxxxxxxx> > > Currently, changing the parameters of a DLCI gives no direct control to the > user whether this should trigger a channel reset or not. The decision is > solely made by the driver based on the assumption which parameter changes > are compatible or not. Therefore, the user has no means to perform an > automatic channel reset after parameter configuration for non-conflicting > changes. > > Add the parameter 'restart' to 'gsm_dlci_config' to force a channel reset > after ioctl setting regardless of whether the changes made require this or > not. > > Note that the parameter is limited to the values 0 and 1 to allow future > additions here. > > Signed-off-by: Daniel Starke <daniel.starke@xxxxxxxxxxx> > --- > drivers/tty/n_gsm.c | 4 ++++ > include/uapi/linux/gsmmux.h | 3 ++- > 2 files changed, 6 insertions(+), 1 deletion(-) > > v2 -> v3: > No changes. > > Link: https://lore.kernel.org/all/20230420085017.7314-2-daniel.starke@xxxxxxxxxxx/ > > diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c > index b411a26cc092..00f692e2e810 100644 > --- a/drivers/tty/n_gsm.c > +++ b/drivers/tty/n_gsm.c > @@ -2532,6 +2532,8 @@ static int gsm_dlci_config(struct gsm_dlci *dlci, struct gsm_dlci_config *dc, in > return -EINVAL; > if (dc->k > 7) > return -EINVAL; > + if (dc->restart > 1) /* allow future extensions */ > + return -EINVAL; > > /* > * See what is needed for reconfiguration > @@ -2546,6 +2548,8 @@ static int gsm_dlci_config(struct gsm_dlci *dlci, struct gsm_dlci_config *dc, in > /* Requires care */ > if (dc->priority != dlci->prio) > need_restart = true; > + if (dc->restart) > + need_restart = true; > > if ((open && gsm->wait_config) || need_restart) > need_open = true; > diff --git a/include/uapi/linux/gsmmux.h b/include/uapi/linux/gsmmux.h > index eb67884e5f38..33ee7b857c52 100644 > --- a/include/uapi/linux/gsmmux.h > +++ b/include/uapi/linux/gsmmux.h > @@ -58,7 +58,8 @@ struct gsm_dlci_config { > __u32 priority; /* Priority (0 for default value) */ > __u32 i; /* Frame type (1 = UIH, 2 = UI) */ > __u32 k; /* Window size (0 for default value) */ > - __u32 reserved[8]; /* For future use, must be initialized to zero */ > + __u32 restart; /* Force DLCI channel reset? */ Why are you using a full 32 bits for just 1 bit of data here? Why not use a bitfield? And what happened to the request to turn the documentation for this structure into proper kerneldoc format? thanks, greg k-h
