Revert "serial:serial_core: Allow use of CTS for PPS line discipline"

This reverts commit c550f01c810f2197c98e6e3103f81797f5e063be.

Turns out the samsung tty driver is mucking around in the "unused" port
fields and this patch breaks that code :(

So we need to fix that driver up before this can be accepted.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Steve Sakoman <steve@sakoman.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 1 insertions, 69 deletions

diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 0a4e6eeb5ff3..70402cdb4d8c 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -2724,57 +2724,6 @@ static ssize_t uart_get_attr_iomem_reg_shift(struct device *dev,
 	return snprintf(buf, PAGE_SIZE, "%d\n", tmp.iomem_reg_shift);
 }
 
-static ssize_t pps_4wire_show(struct device *dev,
-	struct device_attribute *attr, char *buf)
-{
-	struct tty_port *port = dev_get_drvdata(dev);
-	struct uart_state *state = container_of(port, struct uart_state, port);
-	struct uart_port *uport;
-	int mode = 0;
-
-	mutex_lock(&port->mutex);
-	uport = uart_port_check(state);
-	if (!uport)
-		goto out;
-
-	mode = uport->pps_4wire;
-
-out:
-	mutex_unlock(&port->mutex);
-	return sprintf(buf, mode ? "yes\n" : "no\n");
-}
-
-static ssize_t pps_4wire_store(struct device *dev,
-	struct device_attribute *attr, const char *buf, size_t count)
-{
-	struct tty_port *port = dev_get_drvdata(dev);
-	struct uart_state *state = container_of(port, struct uart_state, port);
-	struct uart_port *uport;
-	bool mode;
-	int ret;
-
-	if (!count)
-		return -EINVAL;
-
-	ret = kstrtobool(buf, &mode);
-	if (ret < 0)
-		return ret;
-
-	mutex_lock(&port->mutex);
-	uport = uart_port_check(state);
-	if (!uport)
-		goto out;
-
-	spin_lock_irq(&uport->lock);
-	uport->pps_4wire = mode;
-	spin_unlock_irq(&uport->lock);
-
-out:
-	mutex_unlock(&port->mutex);
-	return count;
-}
-static DEVICE_ATTR_RW(pps_4wire);
-
 static DEVICE_ATTR(type, S_IRUSR | S_IRGRP, uart_get_attr_type, NULL);
 static DEVICE_ATTR(line, S_IRUSR | S_IRGRP, uart_get_attr_line, NULL);
 static DEVICE_ATTR(port, S_IRUSR | S_IRGRP, uart_get_attr_port, NULL);
@@ -2803,7 +2752,6 @@ static struct attribute *tty_dev_attrs[] = {
 	&dev_attr_io_type.attr,
 	&dev_attr_iomem_base.attr,
 	&dev_attr_iomem_reg_shift.attr,
-	&dev_attr_pps_4wire.attr,
 	NULL,
 	};
 
@@ -2860,9 +2808,6 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *uport)
 		goto out;
 	}
 
-	/* assert that pps handling is done via DCD as default */
-	uport->pps_4wire = 0;
-
 	/*
 	 * If this port is a console, then the spinlock is already
 	 * initialised.
@@ -3038,7 +2983,7 @@ void uart_handle_dcd_change(struct uart_port *uport, unsigned int status)
 
 	lockdep_assert_held_once(&uport->lock);
 
-	if (tty && !uport->pps_4wire) {
+	if (tty) {
 		ld = tty_ldisc_ref(tty);
 		if (ld) {
 			if (ld->ops->dcd_change)
@@ -3067,21 +3012,8 @@ EXPORT_SYMBOL_GPL(uart_handle_dcd_change);
  */
 void uart_handle_cts_change(struct uart_port *uport, unsigned int status)
 {
-	struct tty_port *port = &uport->state->port;
-	struct tty_struct *tty = port->tty;
-	struct tty_ldisc *ld;
-
 	lockdep_assert_held_once(&uport->lock);
 
-	if (tty && uport->pps_4wire) {
-		ld = tty_ldisc_ref(tty);
-		if (ld) {
-			if (ld->ops->dcd_change)
-				ld->ops->dcd_change(tty, status);
-			tty_ldisc_deref(ld);
-		}
-	}
-
 	uport->icount.cts++;
 
 	if (uart_softcts_mode(uport)) {