Merge tag 'tty-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel…

…/git/gregkh/tty

Pull tty/serial driver updates from Greg KH:
 "Here's the big tty/serial driver update for 3.13-rc1.

  There's some more minor n_tty work here, but nothing like previous
  kernel releases.  Also some new driver ids, driver updates for new
  hardware, and other small things.

  All of this has been in linux-next for a while with no issues"

* tag 'tty-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (84 commits)
  serial: omap: fix missing comma
  serial: sh-sci: Enable the driver on all ARM platforms
  serial: mfd: Staticize local symbols
  serial: omap: fix a few checkpatch warnings
  serial: omap: improve RS-485 performance
  mrst_max3110: fix unbalanced IRQ issue during resume
  serial: omap: Add support for optional wake-up
  serial: sirf: remove duplicate defines
  tty: xuartps: Fix build error when COMMON_CLK is not set
  tty: xuartps: Fix build error due to missing forward declaration
  tty: xuartps: Fix "may be used uninitialized" build warning
  serial: 8250_pci: add Pericom PCIe Serial board Support (12d8:7952/4/8) - Chip PI7C9X7952/4/8
  tty: xuartps: Update copyright information
  tty: xuartps: Implement suspend/resume callbacks
  tty: xuartps: Dynamically adjust to input frequency changes
  tty: xuartps: Updating set_baud_rate()
  tty: xuartps: Force enable the UART in xuartps_console_write
  tty: xuartps: support 64 byte FIFO size
  tty: xuartps: Add polled mode support for xuartps
  tty: xuartps: Implement BREAK detection, add SYSRQ support
  ...

Documentation/serial/driver

@@ -264,10 +264,6 @@ hardware.
 	Locking: none.
 	Interrupts: caller dependent.
 
-  set_wake(port,state)
-	Enable/disable power management wakeup on serial activity.  Not
-	currently implemented.
-
   type(port)
 	Return a pointer to a string constant describing the specified
 	port, or return NULL, in which case the string 'unknown' is

Documentation/sysrq.txt

@@ -11,27 +11,29 @@ regardless of whatever else it is doing, unless it is completely locked up.
 You need to say "yes" to 'Magic SysRq key (CONFIG_MAGIC_SYSRQ)' when
 configuring the kernel. When running a kernel with SysRq compiled in,
 /proc/sys/kernel/sysrq controls the functions allowed to be invoked via
-the SysRq key. By default the file contains 1 which means that every
-possible SysRq request is allowed (in older versions SysRq was disabled
-by default, and you were required to specifically enable it at run-time
-but this is not the case any more). Here is the list of possible values
-in /proc/sys/kernel/sysrq:
+the SysRq key. The default value in this file is set by the
+CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE config symbol, which itself defaults
+to 1. Here is the list of possible values in /proc/sys/kernel/sysrq:
    0 - disable sysrq completely
    1 - enable all functions of sysrq
   >1 - bitmask of allowed sysrq functions (see below for detailed function
        description):
-          2 - enable control of console logging level
-          4 - enable control of keyboard (SAK, unraw)
-          8 - enable debugging dumps of processes etc.
-         16 - enable sync command
-         32 - enable remount read-only
-         64 - enable signalling of processes (term, kill, oom-kill)
-        128 - allow reboot/poweroff
-        256 - allow nicing of all RT tasks
+          2 =   0x2 - enable control of console logging level
+          4 =   0x4 - enable control of keyboard (SAK, unraw)
+          8 =   0x8 - enable debugging dumps of processes etc.
+         16 =  0x10 - enable sync command
+         32 =  0x20 - enable remount read-only
+         64 =  0x40 - enable signalling of processes (term, kill, oom-kill)
+        128 =  0x80 - allow reboot/poweroff
+        256 = 0x100 - allow nicing of all RT tasks
 
 You can set the value in the file by the following command:
     echo "number" >/proc/sys/kernel/sysrq
 
+The number may be written here either as decimal or as hexadecimal
+with the 0x prefix. CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE must always be
+written in hexadecimal.
+
 Note that the value of /proc/sys/kernel/sysrq influences only the invocation
 via a keyboard. Invocation of any operation via /proc/sysrq-trigger is always
 allowed (by a user with admin privileges).

drivers/tty/bfin_jtag_comm.c

@@ -349,7 +349,7 @@ bfin_jc_early_write(struct console *co, const char *buf, unsigned int count)
 	bfin_jc_straight_buffer_write(buf, count);
 }
 
-static struct __initdata console bfin_jc_early_console = {
+static struct console bfin_jc_early_console __initdata = {
 	.name   = "early_BFJC",
 	.write   = bfin_jc_early_write,
 	.flags   = CON_ANYTIME | CON_PRINTBUFFER,

drivers/tty/hvc/hvc_dcc.c

@@ -86,20 +86,41 @@ static int hvc_dcc_get_chars(uint32_t vt, char *buf, int count)
 	return i;
 }
 
+static bool hvc_dcc_check(void)
+{
+	unsigned long time = jiffies + (HZ / 10);
+
+	/* Write a test character to check if it is handled */
+	__dcc_putchar('\n');
+
+	while (time_is_after_jiffies(time)) {
+		if (!(__dcc_getstatus() & DCC_STATUS_TX))
+			return true;
+	}
+
+	return false;
+}
+
 static const struct hv_ops hvc_dcc_get_put_ops = {
 	.get_chars = hvc_dcc_get_chars,
 	.put_chars = hvc_dcc_put_chars,
 };
 
 static int __init hvc_dcc_console_init(void)
 {
+	if (!hvc_dcc_check())
+		return -ENODEV;
+
 	hvc_instantiate(0, 0, &hvc_dcc_get_put_ops);
 	return 0;
 }
 console_initcall(hvc_dcc_console_init);
 
 static int __init hvc_dcc_init(void)
 {
+	if (!hvc_dcc_check())
+		return -ENODEV;
+
 	hvc_alloc(0, 0, &hvc_dcc_get_put_ops, 128);
 	return 0;
 }

drivers/tty/hvc/hvc_vio.c

@@ -48,6 +48,7 @@
 #include <asm/prom.h>
 #include <asm/hvsi.h>
 #include <asm/udbg.h>
+#include <asm/machdep.h>
 
 #include "hvc_console.h"
 
@@ -457,7 +458,9 @@ void __init hvc_vio_init_early(void)
 	if (hvterm_priv0.proto == HV_PROTOCOL_HVSI)
 		goto out;
 #endif
-	add_preferred_console("hvc", 0, NULL);
+	/* Check whether the user has requested a different console. */
+	if (!strstr(cmd_line, "console="))
+		add_preferred_console("hvc", 0, NULL);
 	hvc_instantiate(0, 0, ops);
 out:
 	of_node_put(stdout_node);

drivers/tty/n_tty.c

@@ -767,7 +767,7 @@ static size_t __process_echoes(struct tty_struct *tty)
 	 * of echo overrun before the next commit), then discard enough
 	 * data at the tail to prevent a subsequent overrun */
 	while (ldata->echo_commit - tail >= ECHO_DISCARD_WATERMARK) {
-		if (echo_buf(ldata, tail == ECHO_OP_START)) {
+		if (echo_buf(ldata, tail) == ECHO_OP_START) {
 			if (echo_buf(ldata, tail) == ECHO_OP_ERASE_TAB)
 				tail += 3;
 			else
@@ -1752,20 +1752,14 @@ int is_ignored(int sig)
 static void n_tty_set_termios(struct tty_struct *tty, struct ktermios *old)
 {
 	struct n_tty_data *ldata = tty->disc_data;
-	int canon_change = 1;
 
-	if (old)
-		canon_change = (old->c_lflag ^ tty->termios.c_lflag) & ICANON;
-	if (canon_change) {
+	if (!old || (old->c_lflag ^ tty->termios.c_lflag) & ICANON) {
 		bitmap_zero(ldata->read_flags, N_TTY_BUF_SIZE);
 		ldata->line_start = ldata->canon_head = ldata->read_tail;
 		ldata->erasing = 0;
 		ldata->lnext = 0;
 	}
 
-	if (canon_change && !L_ICANON(tty) && read_cnt(ldata))
-		wake_up_interruptible(&tty->read_wait);
-
 	ldata->icanon = (L_ICANON(tty) != 0);
 
 	if (I_ISTRIP(tty) || I_IUCLC(tty) || I_IGNCR(tty) ||
@@ -1820,9 +1814,8 @@ static void n_tty_set_termios(struct tty_struct *tty, struct ktermios *old)
 	 * Fix tty hang when I_IXON(tty) is cleared, but the tty
 	 * been stopped by STOP_CHAR(tty) before it.
 	 */
-	if (!I_IXON(tty) && old && (old->c_iflag & IXON) && !tty->flow_stopped) {
+	if (!I_IXON(tty) && old && (old->c_iflag & IXON) && !tty->flow_stopped)
 		start_tty(tty);
-	}
 
 	/* The termios change make the tty ready for I/O */
 	wake_up_interruptible(&tty->write_wait);

drivers/tty/nozomi.c

@@ -959,7 +959,7 @@ static int receive_flow_control(struct nozomi *dc)
 		dev_err(&dc->pdev->dev,
 			"ERROR: flow control received for non-existing port\n");
 		return 0;
-	};
+	}
 
 	DBG1("0x%04X->0x%04X", *((u16 *)&dc->port[port].ctrl_dl),
 	   *((u16 *)&ctrl_dl));
@@ -1025,7 +1025,7 @@ static enum ctrl_port_type port2ctrl(enum port_type port,
 		dev_err(&dc->pdev->dev,
 			"ERROR: send flow control " \
 			"received for non-existing port\n");
-	};
+	}
 	return CTRL_ERROR;
 }
 
@@ -1805,7 +1805,7 @@ static int ntty_ioctl(struct tty_struct *tty,
 	default:
 		DBG1("ERR: 0x%08X, %d", cmd, cmd);
 		break;
-	};
+	}
 
 	return rval;
 }

drivers/tty/serial/8250/8250_core.c

@@ -2322,7 +2322,7 @@ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios,
 
 	if (up->capabilities & UART_CAP_FIFO && port->fifosize > 1) {
 		fcr = uart_config[port->type].fcr;
-		if (baud < 2400 || fifo_bug) {
+		if ((baud < 2400 && !up->dma) || fifo_bug) {
 			fcr &= ~UART_FCR_TRIGGER_MASK;
 			fcr |= UART_FCR_TRIGGER_1;
 		}

drivers/tty/serial/8250/8250_dw.c

@@ -56,11 +56,11 @@
 
 
 struct dw8250_data {
-	int		last_lcr;
-	int		last_mcr;
-	int		line;
-	struct clk	*clk;
-	u8		usr_reg;
+	u8			usr_reg;
+	int			last_mcr;
+	int			line;
+	struct clk		*clk;
+	struct uart_8250_dma	dma;
 };
 
 static inline int dw8250_modify_msr(struct uart_port *p, int offset, int value)
@@ -76,17 +76,33 @@ static inline int dw8250_modify_msr(struct uart_port *p, int offset, int value)
 	return value;
 }
 
+static void dw8250_force_idle(struct uart_port *p)
+{
+	serial8250_clear_and_reinit_fifos(container_of
+					  (p, struct uart_8250_port, port));
+	(void)p->serial_in(p, UART_RX);
+}
+
 static void dw8250_serial_out(struct uart_port *p, int offset, int value)
 {
 	struct dw8250_data *d = p->private_data;
 
-	if (offset == UART_LCR)
-		d->last_lcr = value;
-
 	if (offset == UART_MCR)
 		d->last_mcr = value;
 
 	writeb(value, p->membase + (offset << p->regshift));
+
+	/* Make sure LCR write wasn't ignored */
+	if (offset == UART_LCR) {
+		int tries = 1000;
+		while (tries--) {
+			if (value == p->serial_in(p, UART_LCR))
+				return;
+			dw8250_force_idle(p);
+			writeb(value, p->membase + (UART_LCR << p->regshift));
+		}
+		dev_err(p->dev, "Couldn't set LCR to %d\n", value);
+	}
 }
 
 static unsigned int dw8250_serial_in(struct uart_port *p, int offset)
@@ -107,13 +123,22 @@ static void dw8250_serial_out32(struct uart_port *p, int offset, int value)
 {
 	struct dw8250_data *d = p->private_data;
 
-	if (offset == UART_LCR)
-		d->last_lcr = value;
-
 	if (offset == UART_MCR)
 		d->last_mcr = value;
 
 	writel(value, p->membase + (offset << p->regshift));
+
+	/* Make sure LCR write wasn't ignored */
+	if (offset == UART_LCR) {
+		int tries = 1000;
+		while (tries--) {
+			if (value == p->serial_in(p, UART_LCR))
+				return;
+			dw8250_force_idle(p);
+			writel(value, p->membase + (UART_LCR << p->regshift));
+		}
+		dev_err(p->dev, "Couldn't set LCR to %d\n", value);
+	}
 }
 
 static unsigned int dw8250_serial_in32(struct uart_port *p, int offset)
@@ -131,9 +156,8 @@ static int dw8250_handle_irq(struct uart_port *p)
 	if (serial8250_handle_irq(p, iir)) {
 		return 1;
 	} else if ((iir & UART_IIR_BUSY) == UART_IIR_BUSY) {
-		/* Clear the USR and write the LCR again. */
+		/* Clear the USR */
 		(void)p->serial_in(p, d->usr_reg);
-		p->serial_out(p, UART_LCR, d->last_lcr);
 
 		return 1;
 	}
@@ -153,6 +177,14 @@ dw8250_do_pm(struct uart_port *port, unsigned int state, unsigned int old)
 		pm_runtime_put_sync_suspend(port->dev);
 }
 
+static bool dw8250_dma_filter(struct dma_chan *chan, void *param)
+{
+	struct dw8250_data *data = param;
+
+	return chan->chan_id == data->dma.tx_chan_id ||
+	       chan->chan_id == data->dma.rx_chan_id;
+}
+
 static void dw8250_setup_port(struct uart_8250_port *up)
 {
 	struct uart_port	*p = &up->port;
@@ -241,7 +273,8 @@ static int dw8250_probe_of(struct uart_port *p,
 }
 
 #ifdef CONFIG_ACPI
-static int dw8250_probe_acpi(struct uart_8250_port *up)
+static int dw8250_probe_acpi(struct uart_8250_port *up,
+			     struct dw8250_data *data)
 {
 	const struct acpi_device_id *id;
 	struct uart_port *p = &up->port;
@@ -260,17 +293,16 @@ static int dw8250_probe_acpi(struct uart_8250_port *up)
 	if (!p->uartclk)
 		p->uartclk = (unsigned int)id->driver_data;
 
-	up->dma = devm_kzalloc(p->dev, sizeof(*up->dma), GFP_KERNEL);
-	if (!up->dma)
-		return -ENOMEM;
+	up->dma = &data->dma;
 
 	up->dma->rxconf.src_maxburst = p->fifosize / 4;
 	up->dma->txconf.dst_maxburst = p->fifosize / 4;
 
 	return 0;
 }
 #else
-static inline int dw8250_probe_acpi(struct uart_8250_port *up)
+static inline int dw8250_probe_acpi(struct uart_8250_port *up,
+				    struct dw8250_data *data)
 {
 	return -ENODEV;
 }
@@ -314,6 +346,12 @@ static int dw8250_probe(struct platform_device *pdev)
 		uart.port.uartclk = clk_get_rate(data->clk);
 	}
 
+	data->dma.rx_chan_id = -1;
+	data->dma.tx_chan_id = -1;
+	data->dma.rx_param = data;
+	data->dma.tx_param = data;
+	data->dma.fn = dw8250_dma_filter;
+
 	uart.port.iotype = UPIO_MEM;
 	uart.port.serial_in = dw8250_serial_in;
 	uart.port.serial_out = dw8250_serial_out;
@@ -324,7 +362,7 @@ static int dw8250_probe(struct platform_device *pdev)
 		if (err)
 			return err;
 	} else if (ACPI_HANDLE(&pdev->dev)) {
-		err = dw8250_probe_acpi(&uart);
+		err = dw8250_probe_acpi(&uart, data);
 		if (err)
 			return err;
 	} else {

drivers/tty/serial/8250/8250_em.c

@@ -122,7 +122,7 @@ static int serial8250_em_probe(struct platform_device *pdev)
 	up.port.dev = &pdev->dev;
 	up.port.private_data = priv;
 
-	clk_enable(priv->sclk);
+	clk_prepare_enable(priv->sclk);
 	up.port.uartclk = clk_get_rate(priv->sclk);
 
 	up.port.iotype = UPIO_MEM32;
@@ -134,7 +134,7 @@ static int serial8250_em_probe(struct platform_device *pdev)
 	ret = serial8250_register_8250_port(&up);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "unable to register 8250 port\n");
-		clk_disable(priv->sclk);
+		clk_disable_unprepare(priv->sclk);
 		return ret;
 	}
 
@@ -148,7 +148,7 @@ static int serial8250_em_remove(struct platform_device *pdev)
 	struct serial8250_em_priv *priv = platform_get_drvdata(pdev);
 
 	serial8250_unregister_port(priv->line);
-	clk_disable(priv->sclk);
+	clk_disable_unprepare(priv->sclk);
 	return 0;
 }