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

Conflicts:
	arch/arm64/kernel/early_printk.c

Documentation/devicetree/bindings/serial/nxp,sc16is7xx.txt

+* NXP SC16IS7xx advanced Universal Asynchronous Receiver-Transmitter (UART)
+
+Required properties:
+- compatible: Should be one of the following:
+  - "nxp,sc16is740" for NXP SC16IS740,
+  - "nxp,sc16is741" for NXP SC16IS741,
+  - "nxp,sc16is750" for NXP SC16IS750,
+  - "nxp,sc16is752" for NXP SC16IS752,
+  - "nxp,sc16is760" for NXP SC16IS760,
+  - "nxp,sc16is762" for NXP SC16IS762.
+- reg: I2C address of the SC16IS7xx device.
+- interrupt-parent: The phandle for the interrupt controller that
+  services interrupts for this IC.
+- interrupts: Should contain the UART interrupt
+- clocks: Reference to the IC source clock.
+
+Optional properties:
+- gpio-controller: Marks the device node as a GPIO controller.
+- #gpio-cells: Should be two. The first cell is the GPIO number and
+  the second cell is used to specify the GPIO polarity:
+    0 = active high,
+    1 = active low.
+
+Example:
+        sc16is750: sc16is750@51 {
+                compatible = "nxp,sc16is750";
+                reg = <0x51>;
+                clocks = <&clk20m>;
+                interrupt-parent = <&gpio3>;
+                interrupts = <7 IRQ_TYPE_EDGE_FALLING>;
+                gpio-controller;
+                #gpio-cells = <2>;
+        };

Documentation/kernel-parameters.txt

@@ -883,6 +883,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			which are not unmapped.
 
 	earlycon=	[KNL] Output early console device and options.
+
 		uart[8250],io,<addr>[,options]
 		uart[8250],mmio,<addr>[,options]
 		uart[8250],mmio32,<addr>[,options]
@@ -892,6 +893,14 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			(mmio) or 32-bit (mmio32).
 			The options are the same as for ttyS, above.
 
+		pl011,<addr>
+			Start an early, polled-mode console on a pl011 serial
+			port at the specified address. The pl011 serial port
+			must already be setup and configured. Options are not
+			yet supported.
+
+		smh	Use ARM semihosting calls for early console.
+
 	earlyprintk=	[X86,SH,BLACKFIN,ARM]
 			earlyprintk=vga
 			earlyprintk=efi

arch/arm64/Kconfig

@@ -112,6 +112,9 @@ config IOMMU_HELPER
 config KERNEL_MODE_NEON
 	def_bool y
 
+config FIX_EARLYCON_MEM
+	def_bool y
+
 source "init/Kconfig"
 
 source "kernel/Kconfig.freezer"

arch/arm64/Kconfig.debug

@@ -20,15 +20,6 @@ config STRICT_DEVMEM
 
 	  If in doubt, say Y.
 
-config EARLY_PRINTK
-	bool "Early printk support"
-	default y
-	help
-	  Say Y here if you want to have an early console using the
-	  earlyprintk=<name>[,<addr>][,<options>] kernel parameter. It
-	  is assumed that the early console device has been initialised
-	  by the boot loader prior to starting the Linux kernel.
-
 config PID_IN_CONTEXTIDR
 	bool "Write the current PID to the CONTEXTIDR register"
 	help

arch/arm64/kernel/Makefile

@@ -18,7 +18,6 @@ arm64-obj-$(CONFIG_SMP)			+= smp.o smp_spin_table.o topology.o
 arm64-obj-$(CONFIG_PERF_EVENTS)		+= perf_regs.o
 arm64-obj-$(CONFIG_HW_PERF_EVENTS)	+= perf_event.o
 arm64-obj-$(CONFIG_HAVE_HW_BREAKPOINT)	+= hw_breakpoint.o
-arm64-obj-$(CONFIG_EARLY_PRINTK)	+= early_printk.o
 arm64-obj-$(CONFIG_ARM64_CPU_SUSPEND)	+= sleep.o suspend.o
 arm64-obj-$(CONFIG_JUMP_LABEL)		+= jump_label.o
 arm64-obj-$(CONFIG_KGDB)		+= kgdb.o

arch/arm64/kernel/early_printk.c

-/*
- * Earlyprintk support.
- *
- * Copyright (C) 2012 ARM Ltd.
- * Author: Catalin Marinas <catalin.marinas@arm.com>
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * 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, see <http://www.gnu.org/licenses/>.
- */
-#include <linux/kernel.h>
-#include <linux/console.h>
-#include <linux/init.h>
-#include <linux/string.h>
-#include <linux/mm.h>
-#include <linux/io.h>
-
-#include <linux/amba/serial.h>
-#include <linux/serial_reg.h>
-
-#include <asm/fixmap.h>
-
-static void __iomem *early_base;
-static void (*printch)(char ch);
-
-/*
- * PL011 single character TX.
- */
-static void pl011_printch(char ch)
-{
-	while (readl_relaxed(early_base + UART01x_FR) & UART01x_FR_TXFF)
-		;
-	writeb_relaxed(ch, early_base + UART01x_DR);
-	while (readl_relaxed(early_base + UART01x_FR) & UART01x_FR_BUSY)
-		;
-}
-
-/*
- * Semihosting-based debug console
- */
-static void smh_printch(char ch)
-{
-	asm volatile("mov  x1, %0\n"
-		     "mov  x0, #3\n"
-		     "hlt  0xf000\n"
-		     : : "r" (&ch) : "x0", "x1", "memory");
-}
-
-/*
- * 8250/16550 (8-bit aligned registers) single character TX.
- */
-static void uart8250_8bit_printch(char ch)
-{
-	while (!(readb_relaxed(early_base + UART_LSR) & UART_LSR_THRE))
-		;
-	writeb_relaxed(ch, early_base + UART_TX);
-}
-
-/*
- * 8250/16550 (32-bit aligned registers) single character TX.
- */
-static void uart8250_32bit_printch(char ch)
-{
-	while (!(readl_relaxed(early_base + (UART_LSR << 2)) & UART_LSR_THRE))
-		;
-	writel_relaxed(ch, early_base + (UART_TX << 2));
-}
-
-struct earlycon_match {
-	const char *name;
-	void (*printch)(char ch);
-};
-
-static const struct earlycon_match earlycon_match[] __initconst = {
-	{ .name = "pl011", .printch = pl011_printch, },
-	{ .name = "smh", .printch = smh_printch, },
-	{ .name = "uart8250-8bit", .printch = uart8250_8bit_printch, },
-	{ .name = "uart8250-32bit", .printch = uart8250_32bit_printch, },
-	{}
-};
-
-static void early_write(struct console *con, const char *s, unsigned n)
-{
-	while (n-- > 0) {
-		if (*s == '\n')
-			printch('\r');
-		printch(*s);
-		s++;
-	}
-}
-
-static struct console early_console_dev = {
-	.name =		"earlycon",
-	.write =	early_write,
-	.flags =	CON_PRINTBUFFER | CON_BOOT,
-	.index =	-1,
-};
-
-/*
- * Parse earlyprintk=... parameter in the format:
- *
- *   <name>[,<addr>][,<options>]
- *
- * and register the early console. It is assumed that the UART has been
- * initialised by the bootloader already.
- */
-static int __init setup_early_printk(char *buf)
-{
-	const struct earlycon_match *match = earlycon_match;
-	phys_addr_t paddr = 0;
-
-	if (!buf) {
-		pr_warning("No earlyprintk arguments passed.\n");
-		return 0;
-	}
-
-	while (match->name) {
-		size_t len = strlen(match->name);
-		if (!strncmp(buf, match->name, len)) {
-			buf += len;
-			break;
-		}
-		match++;
-	}
-	if (!match->name) {
-		pr_warning("Unknown earlyprintk arguments: %s\n", buf);
-		return 0;
-	}
-
-	/* I/O address */
-	if (!strncmp(buf, ",0x", 3)) {
-		char *e;
-		paddr = simple_strtoul(buf + 1, &e, 16);
-		buf = e;
-	}
-	/* no options parsing yet */
-
-	if (paddr)
-		early_base = (void __iomem *)set_fixmap_offset_io(FIX_EARLYCON_MEM_BASE, paddr);
-
-	printch = match->printch;
-	early_console = &early_console_dev;
-	register_console(&early_console_dev);
-
-	return 0;
-}
-
-early_param("earlyprintk", setup_early_printk);

arch/x86/Kconfig

@@ -261,6 +261,9 @@ config ARCH_HWEIGHT_CFLAGS
 config ARCH_SUPPORTS_UPROBES
 	def_bool y
 
+config FIX_EARLYCON_MEM
+	def_bool y
+
 source "init/Kconfig"
 source "kernel/Kconfig.freezer"
 

drivers/bluetooth/hci_ldisc.c

@@ -118,10 +118,6 @@ static inline struct sk_buff *hci_uart_dequeue(struct hci_uart *hu)
 
 int hci_uart_tx_wakeup(struct hci_uart *hu)
 {
-	struct tty_struct *tty = hu->tty;
-	struct hci_dev *hdev = hu->hdev;
-	struct sk_buff *skb;
-
 	if (test_and_set_bit(HCI_UART_SENDING, &hu->tx_state)) {
 		set_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
 		return 0;
@@ -129,6 +125,22 @@ int hci_uart_tx_wakeup(struct hci_uart *hu)
 
 	BT_DBG("");
 
+	schedule_work(&hu->write_work);
+
+	return 0;
+}
+
+static void hci_uart_write_work(struct work_struct *work)
+{
+	struct hci_uart *hu = container_of(work, struct hci_uart, write_work);
+	struct tty_struct *tty = hu->tty;
+	struct hci_dev *hdev = hu->hdev;
+	struct sk_buff *skb;
+
+	/* REVISIT: should we cope with bad skbs or ->write() returning
+	 * and error value ?
+	 */
+
 restart:
 	clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
 
@@ -153,7 +165,6 @@ int hci_uart_tx_wakeup(struct hci_uart *hu)
 		goto restart;
 
 	clear_bit(HCI_UART_SENDING, &hu->tx_state);
-	return 0;
 }
 
 static void hci_uart_init_work(struct work_struct *work)
@@ -282,6 +293,7 @@ static int hci_uart_tty_open(struct tty_struct *tty)
 	tty->receive_room = 65536;
 
 	INIT_WORK(&hu->init_ready, hci_uart_init_work);
+	INIT_WORK(&hu->write_work, hci_uart_write_work);
 
 	spin_lock_init(&hu->rx_lock);
 
@@ -319,6 +331,8 @@ static void hci_uart_tty_close(struct tty_struct *tty)
 	if (hdev)
 		hci_uart_close(hdev);
 
+	cancel_work_sync(&hu->write_work);
+
 	if (test_and_clear_bit(HCI_UART_PROTO_SET, &hu->flags)) {
 		if (hdev) {
 			if (test_bit(HCI_UART_REGISTERED, &hu->flags))

drivers/bluetooth/hci_uart.h

@@ -68,6 +68,7 @@ struct hci_uart {
 	unsigned long		hdev_flags;
 
 	struct work_struct	init_ready;
+	struct work_struct	write_work;
 
 	struct hci_uart_proto	*proto;
 	void			*priv;

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

@@ -1926,13 +1926,8 @@ static void serial8250_put_poll_char(struct uart_port *port,
 	wait_for_xmitr(up, BOTH_EMPTY);
 	/*
 	 *	Send the character out.
-	 *	If a LF, also do CR...
 	 */
 	serial_port_out(port, UART_TX, c);
-	if (c == 10) {
-		wait_for_xmitr(up, BOTH_EMPTY);
-		serial_port_out(port, UART_TX, 13);
-	}
 
 	/*
 	 *	Finally, wait for transmitter to become empty

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

@@ -62,6 +62,70 @@ struct dw8250_data {
 	struct uart_8250_dma	dma;
 };
 
+struct dw8250_acpi_desc {
+	void (*set_termios)(struct uart_port *p, struct ktermios *termios,
+			    struct ktermios *old);
+};
+
+#define BYT_PRV_CLK			0x800
+#define BYT_PRV_CLK_EN			(1 << 0)
+#define BYT_PRV_CLK_M_VAL_SHIFT		1
+#define BYT_PRV_CLK_N_VAL_SHIFT		16
+#define BYT_PRV_CLK_UPDATE		(1 << 31)
+
+static void byt_set_termios(struct uart_port *p, struct ktermios *termios,
+			    struct ktermios *old)
+{
+	unsigned int baud = tty_termios_baud_rate(termios);
+	unsigned int m, n;
+	u32 reg;
+
+	/*
+	* For baud rates 0.5M, 1M, 1.5M, 2M, 2.5M, 3M, 3.5M and 4M the
+	* dividers must be adjusted.
+	*
+	* uartclk = (m / n) * 100 MHz, where m <= n
+	*/
+	switch (baud) {
+	case 500000:
+	case 1000000:
+	case 2000000:
+	case 4000000:
+		m = 64;
+		n = 100;
+		p->uartclk = 64000000;
+		break;
+	case 3500000:
+		m = 56;
+		n = 100;
+		p->uartclk = 56000000;
+		break;
+	case 1500000:
+	case 3000000:
+		m = 48;
+		n = 100;
+		p->uartclk = 48000000;
+		break;
+	case 2500000:
+		m = 40;
+		n = 100;
+		p->uartclk = 40000000;
+		break;
+	default:
+		m = 2304;
+		n = 3125;
+		p->uartclk = 73728000;
+	}
+
+	/* Reset the clock */
+	reg = (m << BYT_PRV_CLK_M_VAL_SHIFT) | (n << BYT_PRV_CLK_N_VAL_SHIFT);
+	writel(reg, p->membase + BYT_PRV_CLK);
+	reg |= BYT_PRV_CLK_EN | BYT_PRV_CLK_UPDATE;
+	writel(reg, p->membase + BYT_PRV_CLK);
+
+	serial8250_do_set_termios(p, termios, old);
+}
+
 static inline int dw8250_modify_msr(struct uart_port *p, int offset, int value)
 {
 	struct dw8250_data *d = p->private_data;
@@ -278,6 +342,7 @@ static int dw8250_probe_acpi(struct uart_8250_port *up,
 {
 	const struct acpi_device_id *id;
 	struct uart_port *p = &up->port;
+	struct dw8250_acpi_desc *acpi_desc;
 
 	dw8250_setup_port(up);
 
@@ -290,14 +355,18 @@ static int dw8250_probe_acpi(struct uart_8250_port *up,
 	p->serial_out = dw8250_serial_out32;
 	p->regshift = 2;
 
-	if (!p->uartclk)
-		p->uartclk = (unsigned int)id->driver_data;
-
 	up->dma = &data->dma;
 
 	up->dma->rxconf.src_maxburst = p->fifosize / 4;
 	up->dma->txconf.dst_maxburst = p->fifosize / 4;
 
+	acpi_desc = (struct dw8250_acpi_desc *)id->driver_data;
+	if (!acpi_desc)
+		return 0;
+
+	if (acpi_desc->set_termios)
+		p->set_termios = acpi_desc->set_termios;
+
 	return 0;
 }
 
@@ -445,12 +514,16 @@ static const struct of_device_id dw8250_of_match[] = {
 };
 MODULE_DEVICE_TABLE(of, dw8250_of_match);
 
+static struct dw8250_acpi_desc byt_8250_desc = {
+	.set_termios = byt_set_termios,
+};
+
 static const struct acpi_device_id dw8250_acpi_match[] = {
 	{ "INT33C4", 0 },
 	{ "INT33C5", 0 },
 	{ "INT3434", 0 },
 	{ "INT3435", 0 },
-	{ "80860F0A", 0 },
+	{ "80860F0A", (kernel_ulong_t)&byt_8250_desc},
 	{ },
 };
 MODULE_DEVICE_TABLE(acpi, dw8250_acpi_match);

drivers/tty/serial/8250/8250_early.c

@@ -35,18 +35,8 @@
 #include <linux/serial_8250.h>
 #include <asm/io.h>
 #include <asm/serial.h>
-#ifdef CONFIG_FIX_EARLYCON_MEM
-#include <asm/pgtable.h>
-#include <asm/fixmap.h>
-#endif
 
-struct early_serial8250_device {
-	struct uart_port port;
-	char options[16];		/* e.g., 115200n8 */
-	unsigned int baud;
-};
-
-static struct early_serial8250_device early_device;
+static struct earlycon_device *early_device;
 
 unsigned int __weak __init serial8250_early_in(struct uart_port *port, int offset)
 {
@@ -100,7 +90,7 @@ static void __init serial_putc(struct uart_port *port, int c)
 static void __init early_serial8250_write(struct console *console,
 					const char *s, unsigned int count)
 {
-	struct uart_port *port = &early_device.port;
+	struct uart_port *port = &early_device->port;
 	unsigned int ier;
 
 	/* Save the IER and disable interrupts */
@@ -129,7 +119,7 @@ static unsigned int __init probe_baud(struct uart_port *port)
 	return (port->uartclk / 16) / quot;
 }
 
-static void __init init_port(struct early_serial8250_device *device)
+static void __init init_port(struct earlycon_device *device)
 {
 	struct uart_port *port = &device->port;
 	unsigned int divisor;
@@ -148,128 +138,42 @@ static void __init init_port(struct early_serial8250_device *device)
 	serial8250_early_out(port, UART_LCR, c & ~UART_LCR_DLAB);
 }
 
-static int __init parse_options(struct early_serial8250_device *device,
-								char *options)
+static int __init early_serial8250_setup(struct earlycon_device *device,
+					 const char *options)
 {
-	struct uart_port *port = &device->port;
-	int mmio, mmio32, length;
-
-	if (!options)
-		return -ENODEV;
-
-	port->uartclk = BASE_BAUD * 16;
-
-	mmio = !strncmp(options, "mmio,", 5);
-	mmio32 = !strncmp(options, "mmio32,", 7);
-	if (mmio || mmio32) {
-		port->iotype = (mmio ? UPIO_MEM : UPIO_MEM32);
-		port->mapbase = simple_strtoul(options + (mmio ? 5 : 7),
-					       &options, 0);
-		if (mmio32)
-			port->regshift = 2;
-#ifdef CONFIG_FIX_EARLYCON_MEM
-		set_fixmap_nocache(FIX_EARLYCON_MEM_BASE,
-					port->mapbase & PAGE_MASK);
-		port->membase =
-			(void __iomem *)__fix_to_virt(FIX_EARLYCON_MEM_BASE);
-		port->membase += port->mapbase & ~PAGE_MASK;
-#else
-		port->membase = ioremap_nocache(port->mapbase, 64);
-		if (!port->membase) {
-			printk(KERN_ERR "%s: Couldn't ioremap 0x%llx\n",
-				__func__,
-			       (unsigned long long) port->mapbase);
-			return -ENOMEM;
-		}
-#endif
-	} else if (!strncmp(options, "io,", 3)) {
-		port->iotype = UPIO_PORT;
-		port->iobase = simple_strtoul(options + 3, &options, 0);
-		mmio = 0;
-	} else
-		return -EINVAL;
-
-	options = strchr(options, ',');
-	if (options) {
-		options++;
-		device->baud = simple_strtoul(options, NULL, 0);
-		length = min(strcspn(options, " ") + 1,
-			     (size_t)(sizeof(device->options)));
-		strlcpy(device->options, options, length);
-	} else {
-		device->baud = probe_baud(port);
-		snprintf(device->options, sizeof(device->options), "%u",
-			device->baud);
-	}
-
-	if (mmio || mmio32)
-		printk(KERN_INFO
-		       "Early serial console at MMIO%s 0x%llx (options '%s')\n",
-			mmio32 ? "32" : "",
-			(unsigned long long)port->mapbase,
-			device->options);
-	else
-		printk(KERN_INFO
-		      "Early serial console at I/O port 0x%lx (options '%s')\n",
-			port->iobase,
-			device->options);
-
-	return 0;
-}
-
-static struct console early_serial8250_console __initdata = {
-	.name	= "uart",
-	.write	= early_serial8250_write,
-	.flags	= CON_PRINTBUFFER | CON_BOOT,
-	.index	= -1,
-};
-
-static int __init early_serial8250_setup(char *options)
-{
-	struct early_serial8250_device *device = &early_device;
-	int err;
-
-	if (device->port.membase || device->port.iobase)
+	if (!(device->port.membase || device->port.iobase))
 		return 0;
 
-	err = parse_options(device, options);
-	if (err < 0)
-		return err;
+	if (!device->baud)
+		device->baud = probe_baud(&device->port);
 
 	init_port(device);
+
+	early_device = device;
+	device->con->write = early_serial8250_write;
 	return 0;
 }
+EARLYCON_DECLARE(uart8250, early_serial8250_setup);
+EARLYCON_DECLARE(uart, early_serial8250_setup);
 
 int __init setup_early_serial8250_console(char *cmdline)
 {
-	char *options;
-	int err;
+	char match[] = "uart8250";
 
-	options = strstr(cmdline, "uart8250,");
-	if (!options) {
-		options = strstr(cmdline, "uart,");
-		if (!options)
-			return 0;
-	}
+	if (cmdline && cmdline[4] == ',')
+		match[4] = '\0';
 
-	options = strchr(cmdline, ',') + 1;
-	err = early_serial8250_setup(options);
-	if (err < 0)
-		return err;
-
-	register_console(&early_serial8250_console);
-
-	return 0;
+	return setup_earlycon(cmdline, match, early_serial8250_setup);
 }
 
 int serial8250_find_port_for_earlycon(void)
 {
-	struct early_serial8250_device *device = &early_device;
-	struct uart_port *port = &device->port;
+	struct earlycon_device *device = early_device;
+	struct uart_port *port = device ? &device->port : NULL;
 	int line;
 	int ret;
 
-	if (!device->port.membase && !device->port.iobase)
+	if (!port || (!port->membase && !port->iobase))
 		return -ENODEV;
 
 	line = serial8250_find_port(port);
@@ -284,5 +188,3 @@ int serial8250_find_port_for_earlycon(void)
 
 	return ret;
 }
-
-early_param("earlycon", setup_early_serial8250_console);

drivers/tty/serial/8250/Kconfig

@@ -61,6 +61,7 @@ config SERIAL_8250_CONSOLE
 	bool "Console on 8250/16550 and compatible serial port"
 	depends on SERIAL_8250=y
 	select SERIAL_CORE_CONSOLE
+	select SERIAL_EARLYCON
 	---help---
 	  If you say Y here, it will be possible to use a serial port as the
 	  system console (the system console is the device which receives all
@@ -90,11 +91,6 @@ config SERIAL_8250_CONSOLE
 
 	  If unsure, say N.
 
-config FIX_EARLYCON_MEM
-	bool
-	depends on X86
-	default y
-
 config SERIAL_8250_GSC
 	tristate
 	depends on SERIAL_8250 && GSC

drivers/tty/serial/Kconfig

@@ -7,6 +7,13 @@ if TTY
 menu "Serial drivers"
 	depends on HAS_IOMEM
 
+config SERIAL_EARLYCON
+	bool
+	help
+	  Support for early consoles with the earlycon parameter. This enables
+	  the console before standard serial driver is probed. The console is
+	  enabled when early_param is processed.
+
 source "drivers/tty/serial/8250/Kconfig"
 
 comment "Non-8250 serial port support"
@@ -53,6 +60,7 @@ config SERIAL_AMBA_PL011_CONSOLE
 	bool "Support for console on AMBA serial port"
 	depends on SERIAL_AMBA_PL011=y
 	select SERIAL_CORE_CONSOLE
+	select SERIAL_EARLYCON
 	---help---
 	  Say Y here if you wish to use an AMBA PrimeCell UART as the system
 	  console (the system console is the device which receives all kernel
@@ -65,6 +73,16 @@ config SERIAL_AMBA_PL011_CONSOLE
 	  your boot loader (lilo or loadlin) about how to pass options to the
 	  kernel at boot time.)
 
+config SERIAL_EARLYCON_ARM_SEMIHOST
+	bool "Early console using ARM semihosting"
+	depends on ARM64 || ARM
+	select SERIAL_EARLYCON
+	help
+	  Support for early debug console using ARM semihosting. This enables
+	  the console before standard serial driver is probed. This is enabled
+	  with "earlycon=smh" on the kernel command line. The console is
+	  enabled when early_param is processed.
+
 config SERIAL_SB1250_DUART
 	tristate "BCM1xxx on-chip DUART serial support"
 	depends on SIBYTE_SB1xxx_SOC=y
@@ -1160,6 +1178,16 @@ config SERIAL_SCCNXP_CONSOLE
 	help
 	  Support for console on SCCNXP serial ports.
 
+config SERIAL_SC16IS7XX
+	tristate "SC16IS7xx serial support"
+	depends on I2C
+	select SERIAL_CORE
+	select REGMAP_I2C if I2C
+	help
+	  This selects support for SC16IS7xx serial ports.
+	  Supported ICs are SC16IS740, SC16IS741, SC16IS750, SC16IS752,
+	  SC16IS760 and SC16IS762.
+
 config SERIAL_BFIN_SPORT
 	tristate "Blackfin SPORT emulate UART"
 	depends on BLACKFIN
@@ -1369,18 +1397,19 @@ config SERIAL_MXS_AUART_CONSOLE
 	  Enable a MXS AUART port to be the system console.
 
 config SERIAL_XILINX_PS_UART
-	tristate "Xilinx PS UART support"
+	tristate "Cadence (Xilinx Zynq) UART support"
 	depends on OF
 	select SERIAL_CORE
 	help
-	  This driver supports the Xilinx PS UART port.
+	  This driver supports the Cadence UART. It is found e.g. in Xilinx
+	  Zynq.
 
 config SERIAL_XILINX_PS_UART_CONSOLE
-	bool "Xilinx PS UART console support"
+	bool "Cadence UART console support"
 	depends on SERIAL_XILINX_PS_UART=y
 	select SERIAL_CORE_CONSOLE
 	help
-	  Enable a Xilinx PS UART port to be the system console.
+	  Enable a Cadence UART port to be the system console.
 
 config SERIAL_AR933X
 	tristate "AR933X serial port support"
@@ -1508,6 +1537,16 @@ config SERIAL_ST_ASC_CONSOLE
 	depends on SERIAL_ST_ASC=y
 	select SERIAL_CORE_CONSOLE
 
+config SERIAL_MEN_Z135
+	tristate "MEN 16z135 Support"
+	depends on MCB
+	help
+	  Say yes here to enable support for the MEN 16z135 High Speed UART IP-Core
+	  on a MCB carrier.
+
+	  This driver can also be build as a module. If so, the module will be called
+	  men_z135_uart.ko
+
 endmenu
 
 endif # TTY

drivers/tty/serial/Makefile

@@ -5,6 +5,9 @@
 obj-$(CONFIG_SERIAL_CORE) += serial_core.o
 obj-$(CONFIG_SERIAL_21285) += 21285.o
 
+obj-$(CONFIG_SERIAL_EARLYCON) += earlycon.o
+obj-$(CONFIG_SERIAL_EARLYCON_ARM_SEMIHOST) += earlycon-arm-semihost.o
+
 # These Sparc drivers have to appear before others such as 8250
 # which share ttySx minor node space.  Otherwise console device
 # names change and other unplesantries.
@@ -48,6 +51,7 @@ obj-$(CONFIG_SERIAL_MPSC) += mpsc.o
 obj-$(CONFIG_SERIAL_SB1250_DUART) += sb1250-duart.o
 obj-$(CONFIG_ETRAX_SERIAL) += crisv10.o
 obj-$(CONFIG_SERIAL_SCCNXP) += sccnxp.o
+obj-$(CONFIG_SERIAL_SC16IS7XX) += sc16is7xx.o
 obj-$(CONFIG_SERIAL_JSM) += jsm/
 obj-$(CONFIG_SERIAL_TXX9) += serial_txx9.o
 obj-$(CONFIG_SERIAL_VR41XX) += vr41xx_siu.o
@@ -87,3 +91,4 @@ obj-$(CONFIG_SERIAL_EFM32_UART) += efm32-uart.o
 obj-$(CONFIG_SERIAL_ARC)	+= arc_uart.o
 obj-$(CONFIG_SERIAL_RP2)	+= rp2.o
 obj-$(CONFIG_SERIAL_FSL_LPUART)	+= fsl_lpuart.o
+obj-$(CONFIG_SERIAL_MEN_Z135)	+= men_z135_uart.o

drivers/tty/serial/amba-pl011.c

@@ -303,7 +303,7 @@ static void pl011_dma_probe_initcall(struct device *dev, struct uart_amba_port *
 
 	/* Optionally make use of an RX channel as well */
 	chan = dma_request_slave_channel(dev, "rx");
-	
+
 	if (!chan && plat->dma_rx_param) {
 		chan = dma_request_channel(mask, plat->dma_filter, plat->dma_rx_param);
 
@@ -2045,6 +2045,34 @@ static struct console amba_console = {
 };
 
 #define AMBA_CONSOLE	(&amba_console)
+
+static void pl011_putc(struct uart_port *port, int c)
+{
+	while (readl(port->membase + UART01x_FR) & UART01x_FR_TXFF)
+		;
+	writeb(c, port->membase + UART01x_DR);
+	while (readl(port->membase + UART01x_FR) & UART01x_FR_BUSY)
+		;
+}
+
+static void pl011_early_write(struct console *con, const char *s, unsigned n)
+{
+	struct earlycon_device *dev = con->data;
+
+	uart_console_write(&dev->port, s, n, pl011_putc);
+}
+
+static int __init pl011_early_console_setup(struct earlycon_device *device,
+					    const char *opt)
+{
+	if (!device->port.membase)
+		return -ENODEV;
+
+	device->con->write = pl011_early_write;
+	return 0;
+}
+EARLYCON_DECLARE(pl011, pl011_early_console_setup);
+
 #else
 #define AMBA_CONSOLE	NULL
 #endif

drivers/tty/serial/earlycon-arm-semihost.c

+/*
+ * Copyright (C) 2012 ARM Ltd.
+ * Author: Marc Zyngier <marc.zyngier@arm.com>
+ *
+ * Adapted for ARM and earlycon:
+ * Copyright (C) 2014 Linaro Ltd.
+ * Author: Rob Herring <robh@kernel.org>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ */
+#include <linux/kernel.h>
+#include <linux/console.h>
+#include <linux/init.h>
+#include <linux/serial_core.h>
+
+#ifdef CONFIG_THUMB2_KERNEL
+#define SEMIHOST_SWI	"0xab"
+#else
+#define SEMIHOST_SWI	"0x123456"
+#endif
+
+/*
+ * Semihosting-based debug console
+ */
+static void smh_putc(struct uart_port *port, int c)
+{
+#ifdef CONFIG_ARM64
+	asm volatile("mov  x1, %0\n"
+		     "mov  x0, #3\n"
+		     "hlt  0xf000\n"
+		     : : "r" (&c) : "x0", "x1", "memory");
+#else
+	asm volatile("mov  r1, %0\n"
+		     "mov  r0, #3\n"
+		     "svc  " SEMIHOST_SWI "\n"
+		     : : "r" (&c) : "r0", "r1", "memory");
+#endif
+}
+
+static void smh_write(struct console *con, const char *s, unsigned n)
+{
+	struct earlycon_device *dev = con->data;
+	uart_console_write(&dev->port, s, n, smh_putc);
+}
+
+int __init early_smh_setup(struct earlycon_device *device, const char *opt)
+{
+	device->con->write = smh_write;
+	return 0;
+}
+EARLYCON_DECLARE(smh, early_smh_setup);

drivers/tty/serial/earlycon.c

+/*
+ * Copyright (C) 2014 Linaro Ltd.
+ * Author: Rob Herring <robh@kernel.org>
+ *
+ * Based on 8250 earlycon:
+ * (c) Copyright 2004 Hewlett-Packard Development Company, L.P.
+ *	Bjorn Helgaas <bjorn.helgaas@hp.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/console.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/serial_core.h>
+
+#ifdef CONFIG_FIX_EARLYCON_MEM
+#include <asm/fixmap.h>
+#endif
+
+#include <asm/serial.h>
+
+static struct console early_con = {
+	.name =		"earlycon",
+	.flags =	CON_PRINTBUFFER | CON_BOOT,
+	.index =	-1,
+};
+
+static struct earlycon_device early_console_dev = {
+	.con = &early_con,
+};
+
+static void __iomem * __init earlycon_map(unsigned long paddr, size_t size)
+{
+	void __iomem *base;
+#ifdef CONFIG_FIX_EARLYCON_MEM
+	set_fixmap_io(FIX_EARLYCON_MEM_BASE, paddr & PAGE_MASK);
+	base = (void __iomem *)__fix_to_virt(FIX_EARLYCON_MEM_BASE);
+	base += paddr & ~PAGE_MASK;
+#else
+	base = ioremap(paddr, size);
+#endif
+	if (!base)
+		pr_err("%s: Couldn't map 0x%llx\n", __func__,
+		       (unsigned long long)paddr);
+
+	return base;
+}
+
+static int __init parse_options(struct earlycon_device *device,
+				char *options)
+{
+	struct uart_port *port = &device->port;
+	int mmio, mmio32, length;
+	unsigned long addr;
+
+	if (!options)
+		return -ENODEV;
+
+	mmio = !strncmp(options, "mmio,", 5);
+	mmio32 = !strncmp(options, "mmio32,", 7);
+	if (mmio || mmio32) {
+		port->iotype = (mmio ? UPIO_MEM : UPIO_MEM32);
+		options += mmio ? 5 : 7;
+		addr = simple_strtoul(options, NULL, 0);
+		port->mapbase = addr;
+		if (mmio32)
+			port->regshift = 2;
+	} else if (!strncmp(options, "io,", 3)) {
+		port->iotype = UPIO_PORT;
+		options += 3;
+		addr = simple_strtoul(options, NULL, 0);
+		port->iobase = addr;
+		mmio = 0;
+	} else if (!strncmp(options, "0x", 2)) {
+		port->iotype = UPIO_MEM;
+		addr = simple_strtoul(options, NULL, 0);
+		port->mapbase = addr;
+	} else {
+		return -EINVAL;
+	}
+
+	port->uartclk = BASE_BAUD * 16;
+
+	options = strchr(options, ',');
+	if (options) {
+		options++;
+		device->baud = simple_strtoul(options, NULL, 0);
+		length = min(strcspn(options, " ") + 1,
+			     (size_t)(sizeof(device->options)));
+		strlcpy(device->options, options, length);
+	}
+
+	if (mmio || mmio32)
+		pr_info("Early serial console at MMIO%s 0x%llx (options '%s')\n",
+			mmio32 ? "32" : "",
+			(unsigned long long)port->mapbase,
+			device->options);
+	else
+		pr_info("Early serial console at I/O port 0x%lx (options '%s')\n",
+			port->iobase,
+			device->options);
+
+	return 0;
+}
+
+int __init setup_earlycon(char *buf, const char *match,
+			  int (*setup)(struct earlycon_device *, const char *))
+{
+	int err;
+	size_t len;
+	struct uart_port *port = &early_console_dev.port;
+
+	if (!buf || !match || !setup)
+		return 0;
+
+	len = strlen(match);
+	if (strncmp(buf, match, len))
+		return 0;
+	if (buf[len] && (buf[len] != ','))
+		return 0;
+
+	buf += len + 1;
+
+	err = parse_options(&early_console_dev, buf);
+	/* On parsing error, pass the options buf to the setup function */
+	if (!err)
+		buf = NULL;
+
+	if (port->mapbase)
+		port->membase = earlycon_map(port->mapbase, 64);
+
+	early_console_dev.con->data = &early_console_dev;
+	err = setup(&early_console_dev, buf);
+	if (err < 0)
+		return err;
+	if (!early_console_dev.con->write)
+		return -ENODEV;
+
+	register_console(early_console_dev.con);
+	return 0;
+}

drivers/tty/serial/mux.c

@@ -29,7 +29,7 @@
 #include <asm/irq.h>
 #include <asm/parisc-device.h>
 
-#ifdef CONFIG_MAGIC_SYSRQ
+#if defined(CONFIG_SERIAL_MUX_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
 #include <linux/sysrq.h>
 #define SUPPORT_SYSRQ
 #endif
@@ -613,7 +613,7 @@ static void __exit mux_exit(void)
 {
 	/* Delete the Mux timer. */
 	if(port_cnt > 0) {
-		del_timer(&mux_timer);
+		del_timer_sync(&mux_timer);
 #ifdef CONFIG_SERIAL_MUX_CONSOLE
 		unregister_console(&mux_console);
 #endif

drivers/tty/serial/omap-serial.c

@@ -163,10 +163,6 @@ struct uart_omap_port {
 	u8			wakeups_enabled;
 	u32			features;
 
-	int			DTR_gpio;
-	int			DTR_inverted;
-	int			DTR_active;
-
 	struct serial_rs485	rs485;
 	int			rts_gpio;
 
@@ -184,8 +180,6 @@ static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
 /* Forward declaration of functions */
 static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1);
 
-static struct workqueue_struct *serial_omap_uart_wq;
-
 static inline unsigned int serial_in(struct uart_omap_port *up, int offset)
 {
 	offset <<= up->port.regshift;
@@ -398,11 +392,8 @@ static void transmit_chars(struct uart_omap_port *up, unsigned int lsr)
 			break;
 	} while (--count > 0);
 
-	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) {
-		spin_unlock(&up->port.lock);
+	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 		uart_write_wakeup(&up->port);
-		spin_lock(&up->port.lock);
-	}
 
 	if (uart_circ_empty(xmit))
 		serial_omap_stop_tx(&up->port);
@@ -697,16 +688,6 @@ static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
 	serial_out(up, UART_MCR, up->mcr);
 	pm_runtime_mark_last_busy(up->dev);
 	pm_runtime_put_autosuspend(up->dev);
-
-	if (gpio_is_valid(up->DTR_gpio) &&
-	    !!(mctrl & TIOCM_DTR) != up->DTR_active) {
-		up->DTR_active = !up->DTR_active;
-		if (gpio_cansleep(up->DTR_gpio))
-			schedule_work(&up->qos_work);
-		else
-			gpio_set_value(up->DTR_gpio,
-				       up->DTR_active != up->DTR_inverted);
-	}
 }
 
 static void serial_omap_break_ctl(struct uart_port *port, int break_state)
@@ -850,9 +831,6 @@ static void serial_omap_uart_qos_work(struct work_struct *work)
 						qos_work);
 
 	pm_qos_update_request(&up->pm_qos_request, up->latency);
-	if (gpio_is_valid(up->DTR_gpio))
-		gpio_set_value_cansleep(up->DTR_gpio,
-					up->DTR_active != up->DTR_inverted);
 }
 
 static void
@@ -1420,7 +1398,7 @@ serial_omap_ioctl(struct uart_port *port, unsigned int cmd, unsigned long arg)
 
 	switch (cmd) {
 	case TIOCSRS485:
-		if (copy_from_user(&rs485conf, (struct serial_rs485 *) arg,
+		if (copy_from_user(&rs485conf, (void __user *) arg,
 					sizeof(rs485conf)))
 			return -EFAULT;
 
@@ -1428,7 +1406,7 @@ serial_omap_ioctl(struct uart_port *port, unsigned int cmd, unsigned long arg)
 		break;
 
 	case TIOCGRS485:
-		if (copy_to_user((struct serial_rs485 *) arg,
+		if (copy_to_user((void __user *) arg,
 					&(to_uart_omap_port(port)->rs485),
 					sizeof(rs485conf)))
 			return -EFAULT;
@@ -1614,7 +1592,7 @@ static int serial_omap_probe_rs485(struct uart_omap_port *up,
 	/* check for tx enable gpio */
 	up->rts_gpio = of_get_named_gpio_flags(np, "rts-gpio", 0, &flags);
 	if (gpio_is_valid(up->rts_gpio)) {
-		ret = gpio_request(up->rts_gpio, "omap-serial");
+		ret = devm_gpio_request(up->dev, up->rts_gpio, "omap-serial");
 		if (ret < 0)
 			return ret;
 		ret = gpio_direction_output(up->rts_gpio,
@@ -1644,10 +1622,13 @@ static int serial_omap_probe_rs485(struct uart_omap_port *up,
 
 static int serial_omap_probe(struct platform_device *pdev)
 {
-	struct uart_omap_port	*up;
-	struct resource		*mem, *irq;
 	struct omap_uart_port_info *omap_up_info = dev_get_platdata(&pdev->dev);
-	int ret, uartirq = 0, wakeirq = 0;
+	struct uart_omap_port *up;
+	struct resource *mem;
+	void __iomem *base;
+	int uartirq = 0;
+	int wakeirq = 0;
+	int ret;
 
 	/* The optional wakeirq may be specified in the board dts file */
 	if (pdev->dev.of_node) {
@@ -1658,48 +1639,19 @@ static int serial_omap_probe(struct platform_device *pdev)
 		omap_up_info = of_get_uart_port_info(&pdev->dev);
 		pdev->dev.platform_data = omap_up_info;
 	} else {
-		irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
-		if (!irq) {
-			dev_err(&pdev->dev, "no irq resource?\n");
-			return -ENODEV;
-		}
-		uartirq = irq->start;
-	}
-
-	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!mem) {
-		dev_err(&pdev->dev, "no mem resource?\n");
-		return -ENODEV;
-	}
-
-	if (!devm_request_mem_region(&pdev->dev, mem->start, resource_size(mem),
-				pdev->dev.driver->name)) {
-		dev_err(&pdev->dev, "memory region already claimed\n");
-		return -EBUSY;
-	}
-
-	if (gpio_is_valid(omap_up_info->DTR_gpio) &&
-	    omap_up_info->DTR_present) {
-		ret = gpio_request(omap_up_info->DTR_gpio, "omap-serial");
-		if (ret < 0)
-			return ret;
-		ret = gpio_direction_output(omap_up_info->DTR_gpio,
-					    omap_up_info->DTR_inverted);
-		if (ret < 0)
-			return ret;
+		uartirq = platform_get_irq(pdev, 0);
+		if (uartirq < 0)
+			return -EPROBE_DEFER;
 	}
 
 	up = devm_kzalloc(&pdev->dev, sizeof(*up), GFP_KERNEL);
 	if (!up)
 		return -ENOMEM;
 
-	if (gpio_is_valid(omap_up_info->DTR_gpio) &&
-	    omap_up_info->DTR_present) {
-		up->DTR_gpio = omap_up_info->DTR_gpio;
-		up->DTR_inverted = omap_up_info->DTR_inverted;
-	} else
-		up->DTR_gpio = -EINVAL;
-	up->DTR_active = 0;
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	base = devm_ioremap_resource(&pdev->dev, mem);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
 
 	up->dev = &pdev->dev;
 	up->port.dev = &pdev->dev;
@@ -1733,14 +1685,7 @@ static int serial_omap_probe(struct platform_device *pdev)
 
 	sprintf(up->name, "OMAP UART%d", up->port.line);
 	up->port.mapbase = mem->start;
-	up->port.membase = devm_ioremap(&pdev->dev, mem->start,
-						resource_size(mem));
-	if (!up->port.membase) {
-		dev_err(&pdev->dev, "can't ioremap UART\n");
-		ret = -ENOMEM;
-		goto err_ioremap;
-	}
-
+	up->port.membase = base;
 	up->port.flags = omap_up_info->flags;
 	up->port.uartclk = omap_up_info->uartclk;
 	if (!up->port.uartclk) {
@@ -1754,12 +1699,12 @@ static int serial_omap_probe(struct platform_device *pdev)
 	up->calc_latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
 	pm_qos_add_request(&up->pm_qos_request,
 		PM_QOS_CPU_DMA_LATENCY, up->latency);
-	serial_omap_uart_wq = create_singlethread_workqueue(up->name);
 	INIT_WORK(&up->qos_work, serial_omap_uart_qos_work);
 
 	platform_set_drvdata(pdev, up);
 	if (omap_up_info->autosuspend_timeout == 0)
 		omap_up_info->autosuspend_timeout = -1;
+
 	device_init_wakeup(up->dev, true);
 	pm_runtime_use_autosuspend(&pdev->dev);
 	pm_runtime_set_autosuspend_delay(&pdev->dev,
@@ -1786,7 +1731,6 @@ static int serial_omap_probe(struct platform_device *pdev)
 err_add_port:
 	pm_runtime_put(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
-err_ioremap:
 err_rs485:
 err_port_line:
 	dev_err(&pdev->dev, "[UART%d]: failure [%s]: %d\n",

drivers/tty/serial/pch_uart.c

@@ -257,6 +257,8 @@ struct eg20t_port {
 	dma_addr_t			rx_buf_dma;
 
 	struct dentry	*debugfs;
+#define IRQ_NAME_SIZE 17
+	char				irq_name[IRQ_NAME_SIZE];
 
 	/* protect the eg20t_port private structure and io access to membase */
 	spinlock_t lock;
@@ -1343,7 +1345,7 @@ static int pch_uart_startup(struct uart_port *port)
 		return ret;
 
 	ret = request_irq(priv->port.irq, pch_uart_interrupt, IRQF_SHARED,
-			KBUILD_MODNAME, priv);
+			priv->irq_name, priv);
 	if (ret < 0)
 		return ret;
 
@@ -1588,13 +1590,8 @@ static void pch_uart_put_poll_char(struct uart_port *port,
 	wait_for_xmitr(priv, UART_LSR_THRE);
 	/*
 	 * Send the character out.
-	 * If a LF, also do CR...
 	 */
 	iowrite8(c, priv->membase + PCH_UART_THR);
-	if (c == 10) {
-		wait_for_xmitr(priv, UART_LSR_THRE);
-		iowrite8(13, priv->membase + PCH_UART_THR);
-	}
 
 	/*
 	 * Finally, wait for transmitter to become empty
@@ -1818,6 +1815,10 @@ static struct eg20t_port *pch_uart_init_port(struct pci_dev *pdev,
 	priv->port.line = board->line_no;
 	priv->trigger = PCH_UART_HAL_TRIGGER_M;
 
+	snprintf(priv->irq_name, IRQ_NAME_SIZE,
+		 KBUILD_MODNAME ":" PCH_UART_DRIVER_DEVICE "%d",
+		 priv->port.line);
+
 	spin_lock_init(&priv->port.lock);
 
 	pci_set_drvdata(pdev, priv);

drivers/tty/serial/pxa.c

@@ -711,13 +711,8 @@ static void serial_pxa_put_poll_char(struct uart_port *port,
 	wait_for_xmitr(up);
 	/*
 	 *	Send the character out.
-	 *	If a LF, also do CR...
 	 */
 	serial_out(up, UART_TX, c);
-	if (c == 10) {
-		wait_for_xmitr(up);
-		serial_out(up, UART_TX, 13);
-	}
 
 	/*
 	 *	Finally, wait for transmitter to become empty

drivers/tty/serial/serial_core.c

@@ -2239,6 +2239,9 @@ static void uart_poll_put_char(struct tty_driver *driver, int line, char ch)
 		return;
 
 	port = state->uart_port;
+
+	if (ch == '\n')
+		port->ops->poll_put_char(port, '\r');
 	port->ops->poll_put_char(port, ch);
 }
 #endif

drivers/tty/serial/serial_txx9.c

@@ -535,13 +535,8 @@ static void serial_txx9_put_poll_char(struct uart_port *port, unsigned char c)
 	wait_for_xmitr(up);
 	/*
 	 *	Send the character out.
-	 *	If a LF, also do CR...
 	 */
 	sio_out(up, TXX9_SITFIFO, c);
-	if (c == 10) {
-		wait_for_xmitr(up);
-		sio_out(up, TXX9_SITFIFO, 13);
-	}
 
 	/*
 	 *	Finally, wait for transmitter to become empty

include/linux/serial_core.h

@@ -285,6 +285,22 @@ static inline int uart_poll_timeout(struct uart_port *port)
 /*
  * Console helpers.
  */
+struct earlycon_device {
+	struct console *con;
+	struct uart_port port;
+	char options[16];		/* e.g., 115200n8 */
+	unsigned int baud;
+};
+int setup_earlycon(char *buf, const char *match,
+		   int (*setup)(struct earlycon_device *, const char *));
+
+#define EARLYCON_DECLARE(name, func) \
+static int __init name ## _setup_earlycon(char *buf) \
+{ \
+	return setup_earlycon(buf, __stringify(name), func); \
+} \
+early_param("earlycon", name ## _setup_earlycon);
+
 struct uart_port *uart_get_console(struct uart_port *ports, int nr,
 				   struct console *c);
 void uart_parse_options(char *options, int *baud, int *parity, int *bits,

include/linux/tty_ldisc.h

@@ -92,7 +92,10 @@
  *	This function is called by the low-level tty driver to signal
  *	that line discpline should try to send more characters to the
  *	low-level driver for transmission.  If the line discpline does
- *	not have any more data to send, it can just return.
+ *	not have any more data to send, it can just return. If the line
+ *	discipline does have some data to send, please arise a tasklet
+ *	or workqueue to do the real data transfer. Do not send data in
+ *	this hook, it may leads to a deadlock.
  *
  * int (*hangup)(struct tty_struct *)
  *

include/uapi/linux/serial_core.h

@@ -211,7 +211,7 @@
 /* VIA VT8500 SoC */
 #define PORT_VT8500	97
 
-/* Xilinx PSS UART */
+/* Cadence (Xilinx Zynq) UART */
 #define PORT_XUARTPS	98
 
 /* Atheros AR933X SoC */
@@ -238,4 +238,10 @@
 /* Tilera TILE-Gx UART */
 #define PORT_TILEGX	106
 
+/* MEN 16z135 UART */
+#define PORT_MEN_Z135	107
+
+/* SC16IS74xx */
+#define PORT_SC16IS7XX   108
+
 #endif /* _UAPILINUX_SERIAL_CORE_H */

include/uapi/linux/serial_reg.h

@@ -32,7 +32,7 @@
 
 #define UART_IIR	2	/* In:  Interrupt ID Register */
 #define UART_IIR_NO_INT		0x01 /* No interrupts pending */
-#define UART_IIR_ID		0x06 /* Mask for the interrupt ID */
+#define UART_IIR_ID		0x0e /* Mask for the interrupt ID */
 #define UART_IIR_MSI		0x00 /* Modem status interrupt */
 #define UART_IIR_THRI		0x02 /* Transmitter holding register empty */
 #define UART_IIR_RDI		0x04 /* Receiver data interrupt */