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? */ + __u32 reserved[7]; /* For future use, must be initialized to zero */ }; #define GSMIOC_GETCONF_DLCI _IOWR('G', 7, struct gsm_dlci_config) -- 2.34.1
