Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755445AbZLBRTf (ORCPT ); Wed, 2 Dec 2009 12:19:35 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755403AbZLBRTU (ORCPT ); Wed, 2 Dec 2009 12:19:20 -0500 Received: from 81-174-11-161.static.ngi.it ([81.174.11.161]:42291 "EHLO mail.enneenne.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755188AbZLBRTM (ORCPT ); Wed, 2 Dec 2009 12:19:12 -0500 From: Rodolfo Giometti To: linux-kernel@vger.kernel.org Cc: Andrew Morton , David Woodhouse , Dave Jones , Sam Ravnborg , Greg KH , Randy Dunlap , Kay Sievers , Alan Cox , "H. Peter Anvin" , Ingo Molnar , Michael Kerrisk , Christoph Hellwig , Rodolfo Giometti Date: Wed, 2 Dec 2009 18:18:44 +0100 Message-Id: <1259774329-29663-7-git-send-email-giometti@linux.it> X-Mailer: git-send-email 1.6.3.3 In-Reply-To: <1259774329-29663-6-git-send-email-giometti@linux.it> References: <1259774329-29663-1-git-send-email-giometti@linux.it> <1259774329-29663-2-git-send-email-giometti@linux.it> <1259774329-29663-3-git-send-email-giometti@linux.it> <1259774329-29663-4-git-send-email-giometti@linux.it> <1259774329-29663-5-git-send-email-giometti@linux.it> <1259774329-29663-6-git-send-email-giometti@linux.it> X-SA-Exim-Connect-IP: 192.168.32.37 X-SA-Exim-Mail-From: giometti@enneenne.com Subject: [PATCH 06/11] pps: serial clients support. X-SA-Exim-Version: 4.2.1 (built Wed, 25 Jun 2008 17:14:11 +0000) X-SA-Exim-Scanned: Yes (on mail.enneenne.com) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6834 Lines: 240 Adds support, by using the PPS line discipline, for the PPS sources connected with the CD (Carrier Detect) pin of a serial port. Signed-off-by: Rodolfo Giometti --- drivers/pps/clients/Kconfig | 7 ++ drivers/pps/clients/Makefile | 1 + drivers/pps/clients/pps-ldisc.c | 155 +++++++++++++++++++++++++++++++++++++++ include/linux/serial_core.h | 11 +++- 4 files changed, 173 insertions(+), 1 deletions(-) create mode 100644 drivers/pps/clients/pps-ldisc.c diff --git a/drivers/pps/clients/Kconfig b/drivers/pps/clients/Kconfig index 60b83be..487c1c8 100644 --- a/drivers/pps/clients/Kconfig +++ b/drivers/pps/clients/Kconfig @@ -15,4 +15,11 @@ config PPS_CLIENT_KTIMER This driver can also be built as a module. If so, the module will be called ktimer.ko. +config PPS_CLIENT_LDISC + tristate "PPS line discipline" + depends on PPS + help + If you say yes here you get support for a PPS source connected + with the CD (Carrier Detect) pin of your serial port. + endif diff --git a/drivers/pps/clients/Makefile b/drivers/pps/clients/Makefile index f3c1e39..9f5b988 100644 --- a/drivers/pps/clients/Makefile +++ b/drivers/pps/clients/Makefile @@ -3,6 +3,7 @@ # obj-$(CONFIG_PPS_CLIENT_KTIMER) += ktimer.o +obj-$(CONFIG_PPS_CLIENT_LDISC) += pps-ldisc.o ifeq ($(CONFIG_PPS_DEBUG),y) EXTRA_CFLAGS += -DDEBUG diff --git a/drivers/pps/clients/pps-ldisc.c b/drivers/pps/clients/pps-ldisc.c new file mode 100644 index 0000000..c2a7be6 --- /dev/null +++ b/drivers/pps/clients/pps-ldisc.c @@ -0,0 +1,155 @@ +/* + * pps-ldisc.c -- PPS line discipline + * + * + * Copyright (C) 2008 Rodolfo Giometti + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include +#include +#include +#include + +#define PPS_TTY_MAGIC 0x0001 + +static void pps_tty_dcd_change(struct tty_struct *tty, unsigned int status, + struct timespec *ts) +{ + int id = (int) tty->disc_data; + struct timespec __ts; + struct pps_ktime pps_ts; + + /* First of all we get the time stamp... */ + getnstimeofday(&__ts); + + /* Does caller give us a timestamp? */ + if (ts) { /* Yes. Let's use it! */ + pps_ts.sec = ts->tv_sec; + pps_ts.nsec = ts->tv_nsec; + } else { /* No. Do it ourself! */ + pps_ts.sec = __ts.tv_sec; + pps_ts.nsec = __ts.tv_nsec; + } + + /* Now do the PPS event report */ + pps_event(id, &pps_ts, status ? PPS_CAPTUREASSERT : PPS_CAPTURECLEAR, + NULL); + + pr_debug("PPS %s at %lu on source #%d\n", + status ? "assert" : "clear", jiffies, id); +} + +static int pps_tty_open(struct tty_struct *tty) +{ + struct pps_source_info info; + struct tty_driver *drv = tty->driver; + int index = tty->index + drv->name_base; + int ret; + + info.owner = THIS_MODULE; + info.dev = NULL; + snprintf(info.name, PPS_MAX_NAME_LEN, "%s%d", drv->driver_name, index); + snprintf(info.path, PPS_MAX_NAME_LEN, "/dev/%s%d", drv->name, index); + info.mode = PPS_CAPTUREBOTH | \ + PPS_OFFSETASSERT | PPS_OFFSETCLEAR | \ + PPS_CANWAIT | PPS_TSFMT_TSPEC; + + ret = pps_register_source(&info, PPS_CAPTUREBOTH | \ + PPS_OFFSETASSERT | PPS_OFFSETCLEAR); + if (ret < 0) { + pr_err("cannot register PPS source \"%s\"\n", info.path); + return ret; + } + tty->disc_data = (void *) ret; + + /* Should open N_TTY ldisc too */ + ret = n_tty_open(tty); + if (ret < 0) + pps_unregister_source((int) tty->disc_data); + + pr_info("PPS source #%d \"%s\" added\n", ret, info.path); + + return 0; +} + +static void pps_tty_close(struct tty_struct *tty) +{ + int id = (int) tty->disc_data; + + pps_unregister_source(id); + n_tty_close(tty); + + pr_info("PPS source #%d removed\n", id); +} + +struct tty_ldisc_ops pps_ldisc_ops = { + .owner = THIS_MODULE, + .magic = PPS_TTY_MAGIC, + .name = "pps_tty", + .dcd_change = pps_tty_dcd_change, + .open = pps_tty_open, + .close = pps_tty_close, + + /* Now we should use N_TTY ldisc methods in order to have + * normal tty behaviour + */ + .flush_buffer = n_tty_flush_buffer, + .chars_in_buffer = n_tty_chars_in_buffer, + .read = n_tty_read, + .write = n_tty_write, + .ioctl = n_tty_ioctl_helper, + .set_termios = n_tty_set_termios, + .poll = n_tty_poll, + .receive_buf = n_tty_receive_buf, + .write_wakeup = n_tty_write_wakeup +}; + +/* + * Module stuff + */ + +static int __init pps_tty_init(void) +{ + int err; + + err = tty_register_ldisc(N_PPS, &pps_ldisc_ops); + if (err) + pr_err("can't register PPS line discipline\n"); + else + pr_info("PPS line discipline registered\n"); + + return err; +} + +static void __exit pps_tty_cleanup(void) +{ + int err; + + err = tty_unregister_ldisc(N_PPS); + if (err) + pr_err("can't unregister PPS line discipline\n"); + else + pr_info("PPS line discipline removed\n"); +} + +module_init(pps_tty_init); +module_exit(pps_tty_cleanup); + +MODULE_ALIAS_LDISC(N_PPS); +MODULE_AUTHOR("Rodolfo Giometti "); +MODULE_DESCRIPTION("PPS TTY device driver"); +MODULE_LICENSE("GPL"); diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index db532ce..4bfb046 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -488,9 +488,13 @@ uart_handle_dcd_change(struct uart_port *uport, unsigned int status) { struct uart_state *state = uport->state; struct tty_port *port = &state->port; + struct tty_ldisc *ld = tty_ldisc_ref(port->tty); + struct timespec ts; - uport->icount.dcd++; + if (ld && ld->ops->dcd_change) + getnstimeofday(&ts); + uport->icount.dcd++; #ifdef CONFIG_HARD_PPS if ((uport->flags & UPF_HARDPPS_CD) && status) hardpps(); @@ -502,6 +506,11 @@ uart_handle_dcd_change(struct uart_port *uport, unsigned int status) else if (port->tty) tty_hangup(port->tty); } + + if (ld && ld->ops->dcd_change) + ld->ops->dcd_change(port->tty, status, &ts); + if (ld) + tty_ldisc_deref(ld); } /** -- 1.6.3.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/