Re: [PATCH 1/2] tty/hvc_console: Add DTR/RTS callback to handle HUPCL control
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: 2013-10-11 07:15:44
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linux-s390, lkml
On Tue, 2013-07-02 at 17:07 +0200, Hendrik Brueckner wrote:
Introduce a new callback to explicitly handle the HUPCL termios control flag. This prepares for a follow-up commit for the hvc_iucv device driver to improve handling when to drop an established network connection. The callback naming is based on the recently added tty_port interface to facilitate a potential refactoring of the hvc_console to use tty_port functions.
I only just noticed that ... oops. Why add those dtr_rts() calls ? We already have tiocmset in there which is used to set DTR on HVSI consoles such as hvc_opal when using hvsi_lib... Any reason why a separate callback was needed ? Cheers, Ben.
quoted hunk ↗ jump to hunk
Signed-off-by: Hendrik Brueckner <redacted> --- drivers/tty/hvc/hvc_console.c | 11 ++++++++++- drivers/tty/hvc/hvc_console.h | 3 +++ 2 files changed, 13 insertions(+), 1 deletions(-)diff --git a/drivers/tty/hvc/hvc_console.c b/drivers/tty/hvc/hvc_console.c index eb255e8..9eba119 100644 --- a/drivers/tty/hvc/hvc_console.c +++ b/drivers/tty/hvc/hvc_console.c@@ -361,7 +361,12 @@ static int hvc_open(struct tty_struct *tty, struct file * filp) tty->driver_data = NULL; tty_port_put(&hp->port); printk(KERN_ERR "hvc_open: request_irq failed with rc %d.\n", rc); - } + } else + /* We are ready... raise DTR/RTS */ + if (C_BAUD(tty)) + if (hp->ops->dtr_rts) + hp->ops->dtr_rts(hp, 1); + /* Force wakeup of the polling thread */ hvc_kick();@@ -393,6 +398,10 @@ static void hvc_close(struct tty_struct *tty, struct file * filp) /* We are done with the tty pointer now. */ tty_port_tty_set(&hp->port, NULL); + if (C_HUPCL(tty)) + if (hp->ops->dtr_rts) + hp->ops->dtr_rts(hp, 0); + if (hp->ops->notifier_del) hp->ops->notifier_del(hp, hp->data);diff --git a/drivers/tty/hvc/hvc_console.h b/drivers/tty/hvc/hvc_console.h index 674d23c..9131019 100644 --- a/drivers/tty/hvc/hvc_console.h +++ b/drivers/tty/hvc/hvc_console.h@@ -75,6 +75,9 @@ struct hv_ops { /* tiocmget/set implementation */ int (*tiocmget)(struct hvc_struct *hp); int (*tiocmset)(struct hvc_struct *hp, unsigned int set, unsigned int clear); + + /* Callbacks to handle tty ports */ + void (*dtr_rts)(struct hvc_struct *hp, int raise); }; /* Register a vterm and a slot index for use as a console (console_init) */