Make it obvious how the gsm mux number relates to the virtual tty lines by using helper function instead of shifting 6 bits.
Signed-off-by: Martin Hundebøll <mar...@geanix.com> --- drivers/tty/n_gsm.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index c4e16b31f9ab..cba06063c44a 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -2171,6 +2171,16 @@ static inline void mux_put(struct gsm_mux *gsm) kref_put(&gsm->ref, gsm_free_muxr); } +static inline int mux_num_to_base(struct gsm_mux *gsm) +{ + return gsm->num * NUM_DLCI; +} + +static inline unsigned int mux_line_to_num(int line) +{ + return line / NUM_DLCI; +} + /** * gsm_alloc_mux - allocate a mux * @@ -2361,7 +2371,7 @@ static int gsmld_attach_gsm(struct tty_struct *tty, struct gsm_mux *gsm) else { /* Don't register device 0 - this is the control channel and not a usable tty interface */ - base = gsm->num << 6; /* Base for this MUX */ + base = mux_num_to_base(gsm); /* Base for this MUX */ for (i = 1; i < NUM_DLCI; i++) tty_register_device(gsm_tty_driver, base + i, NULL); } @@ -2380,7 +2390,7 @@ static int gsmld_attach_gsm(struct tty_struct *tty, struct gsm_mux *gsm) static void gsmld_detach_gsm(struct tty_struct *tty, struct gsm_mux *gsm) { int i; - int base = gsm->num << 6; /* Base for this MUX */ + int base = mux_num_to_base(gsm); /* Base for this MUX */ WARN_ON(tty != gsm->tty); for (i = 1; i < NUM_DLCI; i++) @@ -2908,7 +2918,7 @@ static int gsmtty_install(struct tty_driver *driver, struct tty_struct *tty) struct gsm_mux *gsm; struct gsm_dlci *dlci; unsigned int line = tty->index; - unsigned int mux = line >> 6; + unsigned int mux = mux_line_to_num(line); bool alloc = false; int ret; -- 2.22.0