Merge branch 'tty-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

* 'tty-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  TTY: ldisc, wait for ldisc infinitely in hangup
  TTY: ldisc, move wait idle to caller
  TTY: ldisc, allow waiting for ldisc arbitrarily long
  Revert "tty/serial: Prevent drop of DCD on suspend for Tegra UARTs"
  RS485: fix inconsistencies in the meaning of some variables
  pch_uart: Fix DMA resource leak issue
  serial,mfd: Fix CMSPAR setup
  tty/serial: Prevent drop of DCD on suspend for Tegra UARTs
  pch_uart: Change company name OKI SEMICONDUCTOR to LAPIS Semiconductor
  pch_uart: Support new device LAPIS Semiconductor ML7831 IOH
  pch_uart: Fix hw-flow control issue
  tty: hvc_dcc: Fix duplicate character inputs
  jsm: Change maintainership

Documentation/serial/serial-rs485.txt

@@ -97,15 +97,23 @@
 
 	struct serial_rs485 rs485conf;
 
-	/* Set RS485 mode: */
+	/* Enable RS485 mode: */
 	rs485conf.flags |= SER_RS485_ENABLED;
 
+	/* Set logical level for RTS pin equal to 1 when sending: */
+	rs485conf.flags |= SER_RS485_RTS_ON_SEND;
+	/* or, set logical level for RTS pin equal to 0 when sending: */
+	rs485conf.flags &= ~(SER_RS485_RTS_ON_SEND);
+
+	/* Set logical level for RTS pin equal to 1 after sending: */
+	rs485conf.flags |= SER_RS485_RTS_AFTER_SEND;
+	/* or, set logical level for RTS pin equal to 0 after sending: */
+	rs485conf.flags &= ~(SER_RS485_RTS_AFTER_SEND);
+
 	/* Set rts delay before send, if needed: */
-	rs485conf.flags |= SER_RS485_RTS_BEFORE_SEND;
 	rs485conf.delay_rts_before_send = ...;
 
 	/* Set rts delay after send, if needed: */
-	rs485conf.flags |= SER_RS485_RTS_AFTER_SEND;
 	rs485conf.delay_rts_after_send = ...;
 
 	/* Set this flag if you want to receive data even whilst sending data */

MAINTAINERS

@@ -3728,7 +3728,7 @@ F:	fs/jbd2/
 F:	include/linux/jbd2.h
 
 JSM Neo PCI based serial card
-M:	Breno Leitao <leitao@linux.vnet.ibm.com>
+M:	Lucas Tavares <lucaskt@linux.vnet.ibm.com>
 L:	linux-serial@vger.kernel.org
 S:	Maintained
 F:	drivers/tty/serial/jsm/

drivers/tty/hvc/hvc_dcc.c

@@ -46,6 +46,7 @@ static inline char __dcc_getchar(void)
 
 	asm volatile("mrc p14, 0, %0, c0, c5, 0	@ read comms data reg"
 		: "=r" (__c));
+	isb();
 
 	return __c;
 }
@@ -55,6 +56,7 @@ static inline void __dcc_putchar(char c)
 	asm volatile("mcr p14, 0, %0, c0, c5, 0	@ write a char"
 		: /* no output register */
 		: "r" (c));
+	isb();
 }
 
 static int hvc_dcc_put_chars(uint32_t vt, const char *buf, int count)

drivers/tty/serial/Kconfig

@@ -1560,7 +1560,7 @@ config SERIAL_IFX6X60
 	  Support for the IFX6x60 modem devices on Intel MID platforms.
 
 config SERIAL_PCH_UART
-	tristate "Intel EG20T PCH / OKI SEMICONDUCTOR IOH(ML7213/ML7223) UART"
+	tristate "Intel EG20T PCH/LAPIS Semicon IOH(ML7213/ML7223/ML7831) UART"
 	depends on PCI
 	select SERIAL_CORE
 	help
@@ -1568,12 +1568,12 @@ config SERIAL_PCH_UART
 	  which is an IOH(Input/Output Hub) for x86 embedded processor.
 	  Enabling PCH_DMA, this PCH UART works as DMA mode.
 
-	  This driver also can be used for OKI SEMICONDUCTOR IOH(Input/
-	  Output Hub), ML7213 and ML7223.
-	  ML7213 IOH is for IVI(In-Vehicle Infotainment) use and ML7223 IOH is
-	  for MP(Media Phone) use.
-	  ML7213/ML7223 is companion chip for Intel Atom E6xx series.
-	  ML7213/ML7223 is completely compatible for Intel EG20T PCH.
+	  This driver also can be used for LAPIS Semiconductor IOH(Input/
+	  Output Hub), ML7213, ML7223 and ML7831.
+	  ML7213 IOH is for IVI(In-Vehicle Infotainment) use, ML7223 IOH is
+	  for MP(Media Phone) use and ML7831 IOH is for general purpose use.
+	  ML7213/ML7223/ML7831 is companion chip for Intel Atom E6xx series.
+	  ML7213/ML7223/ML7831 is completely compatible for Intel EG20T PCH.
 
 config SERIAL_MSM_SMD
 	bool "Enable tty device interface for some SMD ports"

drivers/tty/serial/atmel_serial.c

@@ -228,7 +228,7 @@ void atmel_config_rs485(struct uart_port *port, struct serial_rs485 *rs485conf)
 	if (rs485conf->flags & SER_RS485_ENABLED) {
 		dev_dbg(port->dev, "Setting UART to RS485\n");
 		atmel_port->tx_done_mask = ATMEL_US_TXEMPTY;
-		if (rs485conf->flags & SER_RS485_RTS_AFTER_SEND)
+		if ((rs485conf->delay_rts_after_send) > 0)
 			UART_PUT_TTGR(port, rs485conf->delay_rts_after_send);
 		mode |= ATMEL_US_USMODE_RS485;
 	} else {
@@ -304,7 +304,7 @@ static void atmel_set_mctrl(struct uart_port *port, u_int mctrl)
 
 	if (atmel_port->rs485.flags & SER_RS485_ENABLED) {
 		dev_dbg(port->dev, "Setting UART to RS485\n");
-		if (atmel_port->rs485.flags & SER_RS485_RTS_AFTER_SEND)
+		if ((atmel_port->rs485.delay_rts_after_send) > 0)
 			UART_PUT_TTGR(port,
 					atmel_port->rs485.delay_rts_after_send);
 		mode |= ATMEL_US_USMODE_RS485;
@@ -1228,7 +1228,7 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
 
 	if (atmel_port->rs485.flags & SER_RS485_ENABLED) {
 		dev_dbg(port->dev, "Setting UART to RS485\n");
-		if (atmel_port->rs485.flags & SER_RS485_RTS_AFTER_SEND)
+		if ((atmel_port->rs485.delay_rts_after_send) > 0)
 			UART_PUT_TTGR(port,
 					atmel_port->rs485.delay_rts_after_send);
 		mode |= ATMEL_US_USMODE_RS485;
@@ -1447,16 +1447,6 @@ static void __devinit atmel_of_init_port(struct atmel_uart_port *atmel_port,
 		rs485conf->delay_rts_after_send = rs485_delay[1];
 		rs485conf->flags = 0;
 
-		if (rs485conf->delay_rts_before_send == 0 &&
-		    rs485conf->delay_rts_after_send == 0) {
-			rs485conf->flags |= SER_RS485_RTS_ON_SEND;
-		} else {
-			if (rs485conf->delay_rts_before_send)
-				rs485conf->flags |= SER_RS485_RTS_BEFORE_SEND;
-			if (rs485conf->delay_rts_after_send)
-				rs485conf->flags |= SER_RS485_RTS_AFTER_SEND;
-		}
-
 		if (of_get_property(np, "rs485-rx-during-tx", NULL))
 			rs485conf->flags |= SER_RS485_RX_DURING_TX;
 

drivers/tty/serial/crisv10.c

@@ -3234,8 +3234,7 @@ rs_write(struct tty_struct *tty,
 		e100_disable_rx(info);
 		e100_enable_rx_irq(info);
 #endif
-		if ((info->rs485.flags & SER_RS485_RTS_BEFORE_SEND) &&
-			(info->rs485.delay_rts_before_send > 0))
+		if (info->rs485.delay_rts_before_send > 0)
 			msleep(info->rs485.delay_rts_before_send);
 	}
 #endif /* CONFIG_ETRAX_RS485 */
@@ -3693,10 +3692,6 @@ rs_ioctl(struct tty_struct *tty,
 
 		rs485data.delay_rts_before_send = rs485ctrl.delay_rts_before_send;
 		rs485data.flags = 0;
-		if (rs485data.delay_rts_before_send != 0)
-			rs485data.flags |= SER_RS485_RTS_BEFORE_SEND;
-		else
-			rs485data.flags &= ~(SER_RS485_RTS_BEFORE_SEND);
 
 		if (rs485ctrl.enabled)
 			rs485data.flags |= SER_RS485_ENABLED;
@@ -4531,7 +4526,6 @@ static int __init rs_init(void)
 		/* Set sane defaults */
 		info->rs485.flags &= ~(SER_RS485_RTS_ON_SEND);
 		info->rs485.flags |= SER_RS485_RTS_AFTER_SEND;
-		info->rs485.flags &= ~(SER_RS485_RTS_BEFORE_SEND);
 		info->rs485.delay_rts_before_send = 0;
 		info->rs485.flags &= ~(SER_RS485_ENABLED);
 #endif

drivers/tty/serial/mfd.c

@@ -884,7 +884,6 @@ serial_hsu_set_termios(struct uart_port *port, struct ktermios *termios,
 {
 	struct uart_hsu_port *up =
 			container_of(port, struct uart_hsu_port, port);
-	struct tty_struct *tty = port->state->port.tty;
 	unsigned char cval, fcr = 0;
 	unsigned long flags;
 	unsigned int baud, quot;
@@ -907,8 +906,7 @@ serial_hsu_set_termios(struct uart_port *port, struct ktermios *termios,
 	}
 
 	/* CMSPAR isn't supported by this driver */
-	if (tty)
-		tty->termios->c_cflag &= ~CMSPAR;
+	termios->c_cflag &= ~CMSPAR;
 
 	if (termios->c_cflag & CSTOPB)
 		cval |= UART_LCR_STOP;

drivers/tty/serial/pch_uart.c

 /*
- *Copyright (C) 2010 OKI SEMICONDUCTOR CO., LTD.
+ *Copyright (C) 2011 LAPIS Semiconductor Co., Ltd.
  *
  *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
@@ -46,8 +46,8 @@ enum {
 
 /* Set the max number of UART port
  * Intel EG20T PCH: 4 port
- * OKI SEMICONDUCTOR ML7213 IOH: 3 port
- * OKI SEMICONDUCTOR ML7223 IOH: 2 port
+ * LAPIS Semiconductor ML7213 IOH: 3 port
+ * LAPIS Semiconductor ML7223 IOH: 2 port
 */
 #define PCH_UART_NR	4
 
@@ -258,6 +258,8 @@ enum pch_uart_num_t {
 	pch_ml7213_uart2,
 	pch_ml7223_uart0,
 	pch_ml7223_uart1,
+	pch_ml7831_uart0,
+	pch_ml7831_uart1,
 };
 
 static struct pch_uart_driver_data drv_dat[] = {
@@ -270,6 +272,8 @@ static struct pch_uart_driver_data drv_dat[] = {
 	[pch_ml7213_uart2] = {PCH_UART_2LINE, 2},
 	[pch_ml7223_uart0] = {PCH_UART_8LINE, 0},
 	[pch_ml7223_uart1] = {PCH_UART_2LINE, 1},
+	[pch_ml7831_uart0] = {PCH_UART_8LINE, 0},
+	[pch_ml7831_uart1] = {PCH_UART_2LINE, 1},
 };
 
 static unsigned int default_baud = 9600;
@@ -628,6 +632,7 @@ static void pch_request_dma(struct uart_port *port)
 		dev_err(priv->port.dev, "%s:dma_request_channel FAILS(Rx)\n",
 			__func__);
 		dma_release_channel(priv->chan_tx);
+		priv->chan_tx = NULL;
 		return;
 	}
 
@@ -1215,7 +1220,6 @@ static void pch_uart_shutdown(struct uart_port *port)
 		dev_err(priv->port.dev,
 			"pch_uart_hal_set_fifo Failed(ret=%d)\n", ret);
 
-	if (priv->use_dma_flag)
 	pch_free_dma(port);
 
 	free_irq(priv->port.irq, priv);
@@ -1280,6 +1284,7 @@ static void pch_uart_set_termios(struct uart_port *port,
 	if (rtn)
 		goto out;
 
+	pch_uart_set_mctrl(&priv->port, priv->port.mctrl);
 	/* Don't rewrite B0 */
 	if (tty_termios_baud_rate(termios))
 		tty_termios_encode_baud_rate(termios, baud, baud);
@@ -1552,6 +1557,10 @@ static DEFINE_PCI_DEVICE_TABLE(pch_uart_pci_id) = {
 	 .driver_data = pch_ml7223_uart0},
 	{PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x800D),
 	 .driver_data = pch_ml7223_uart1},
+	{PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8811),
+	 .driver_data = pch_ml7831_uart0},
+	{PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8812),
+	 .driver_data = pch_ml7831_uart1},
 	{0,},
 };
 

drivers/tty/tty_ldisc.c

@@ -36,6 +36,7 @@
 
 #include <linux/kmod.h>
 #include <linux/nsproxy.h>
+#include <linux/ratelimit.h>
 
 /*
  *	This guards the refcounted line discipline lists. The lock
@@ -547,15 +548,16 @@ static void tty_ldisc_flush_works(struct tty_struct *tty)
 /**
  *	tty_ldisc_wait_idle	-	wait for the ldisc to become idle
  *	@tty: tty to wait for
+ *	@timeout: for how long to wait at most
  *
  *	Wait for the line discipline to become idle. The discipline must
  *	have been halted for this to guarantee it remains idle.
  */
-static int tty_ldisc_wait_idle(struct tty_struct *tty)
+static int tty_ldisc_wait_idle(struct tty_struct *tty, long timeout)
 {
-	int ret;
+	long ret;
 	ret = wait_event_timeout(tty_ldisc_idle,
-			atomic_read(&tty->ldisc->users) == 1, 5 * HZ);
+			atomic_read(&tty->ldisc->users) == 1, timeout);
 	if (ret < 0)
 		return ret;
 	return ret > 0 ? 0 : -EBUSY;
@@ -665,7 +667,7 @@ int tty_set_ldisc(struct tty_struct *tty, int ldisc)
 
 	tty_ldisc_flush_works(tty);
 
-	retval = tty_ldisc_wait_idle(tty);
+	retval = tty_ldisc_wait_idle(tty, 5 * HZ);
 
 	tty_lock();
 	mutex_lock(&tty->ldisc_mutex);
@@ -762,8 +764,6 @@ static int tty_ldisc_reinit(struct tty_struct *tty, int ldisc)
 	if (IS_ERR(ld))
 		return -1;
 
-	WARN_ON_ONCE(tty_ldisc_wait_idle(tty));
-
 	tty_ldisc_close(tty, tty->ldisc);
 	tty_ldisc_put(tty->ldisc);
 	tty->ldisc = NULL;
@@ -838,7 +838,7 @@ void tty_ldisc_hangup(struct tty_struct *tty)
 	tty_unlock();
 	cancel_work_sync(&tty->buf.work);
 	mutex_unlock(&tty->ldisc_mutex);
-
+retry:
 	tty_lock();
 	mutex_lock(&tty->ldisc_mutex);
 
@@ -847,6 +847,22 @@ void tty_ldisc_hangup(struct tty_struct *tty)
 	   it means auditing a lot of other paths so this is
 	   a FIXME */
 	if (tty->ldisc) {	/* Not yet closed */
+		if (atomic_read(&tty->ldisc->users) != 1) {
+			char cur_n[TASK_COMM_LEN], tty_n[64];
+			long timeout = 3 * HZ;
+			tty_unlock();
+
+			while (tty_ldisc_wait_idle(tty, timeout) == -EBUSY) {
+				timeout = MAX_SCHEDULE_TIMEOUT;
+				printk_ratelimited(KERN_WARNING
+					"%s: waiting (%s) for %s took too long, but we keep waiting...\n",
+					__func__, get_task_comm(cur_n, current),
+					tty_name(tty, tty_n));
+			}
+			mutex_unlock(&tty->ldisc_mutex);
+			goto retry;
+		}
+
 		if (reset == 0) {
 
 			if (!tty_ldisc_reinit(tty, tty->termios->c_line))

include/linux/serial.h

@@ -207,13 +207,15 @@ struct serial_icounter_struct {
 
 struct serial_rs485 {
 	__u32	flags;			/* RS485 feature flags */
-#define SER_RS485_ENABLED		(1 << 0)
-#define SER_RS485_RTS_ON_SEND		(1 << 1)
-#define SER_RS485_RTS_AFTER_SEND	(1 << 2)
-#define SER_RS485_RTS_BEFORE_SEND	(1 << 3)
+#define SER_RS485_ENABLED		(1 << 0)	/* If enabled */
+#define SER_RS485_RTS_ON_SEND		(1 << 1)	/* Logical level for
+							   RTS pin when
+							   sending */
+#define SER_RS485_RTS_AFTER_SEND	(1 << 2)	/* Logical level for
+							   RTS pin after sent*/
 #define SER_RS485_RX_DURING_TX		(1 << 4)
-	__u32	delay_rts_before_send;	/* Milliseconds */
-	__u32	delay_rts_after_send;	/* Milliseconds */
+	__u32	delay_rts_before_send;	/* Delay before send (milliseconds) */
+	__u32	delay_rts_after_send;	/* Delay after send (milliseconds) */
 	__u32	padding[5];		/* Memory is cheap, new structs
 					   are a royal PITA .. */
 };