Merge pull request #565 from philschenker/update-to-5.4.193__update-to-2.3.7__5.4-2.3.x-imx

Update Patchlevel on Branch 5.4-2.3.x-imx from 5.4.161->5.4.193

17 files changed, 212 insertions, 89 deletions

diff --git a/drivers/tty/serial/8250/8250_fintek.c b/drivers/tty/serial/8250/8250_fintek.c
index 31c91c2f8c6e..e24161004ddc 100644
--- a/drivers/tty/serial/8250/8250_fintek.c
+++ b/drivers/tty/serial/8250/8250_fintek.c
@@ -285,24 +285,6 @@ static void fintek_8250_set_max_fifo(struct fintek_8250 *pdata)
 	}
 }
 
-static void fintek_8250_goto_highspeed(struct uart_8250_port *uart,
-			      struct fintek_8250 *pdata)
-{
-	sio_write_reg(pdata, LDN, pdata->index);
-
-	switch (pdata->pid) {
-	case CHIP_ID_F81866: /* set uart clock for high speed serial mode */
-		sio_write_mask_reg(pdata, F81866_UART_CLK,
-			F81866_UART_CLK_MASK,
-			F81866_UART_CLK_14_769MHZ);
-
-		uart->port.uartclk = 921600 * 16;
-		break;
-	default: /* leave clock speed untouched */
-		break;
-	}
-}
-
 static void fintek_8250_set_termios(struct uart_port *port,
 				    struct ktermios *termios,
 				    struct ktermios *old)
@@ -422,7 +404,6 @@ static int probe_setup_port(struct fintek_8250 *pdata,
 
 				fintek_8250_set_irq_mode(pdata, level_mode);
 				fintek_8250_set_max_fifo(pdata);
-				fintek_8250_goto_highspeed(uart, pdata);
 
 				fintek_8250_exit_key(addr[i]);
 
diff --git a/drivers/tty/serial/8250/8250_gsc.c b/drivers/tty/serial/8250/8250_gsc.c
index 0809ae2aa9b1..51cc985216ff 100644
--- a/drivers/tty/serial/8250/8250_gsc.c
+++ b/drivers/tty/serial/8250/8250_gsc.c
@@ -26,7 +26,7 @@ static int __init serial_init_chip(struct parisc_device *dev)
 	unsigned long address;
 	int err;
 
-#ifdef CONFIG_64BIT
+#if defined(CONFIG_64BIT) && defined(CONFIG_IOSAPIC)
 	if (!dev->irq && (dev->id.sversion == 0xad))
 		dev->irq = iosapic_serial_irq(dev);
 #endif
diff --git a/drivers/tty/serial/8250/8250_mid.c b/drivers/tty/serial/8250/8250_mid.c
index efa0515139f8..e6c1791609dd 100644
--- a/drivers/tty/serial/8250/8250_mid.c
+++ b/drivers/tty/serial/8250/8250_mid.c
@@ -73,6 +73,11 @@ static int pnw_setup(struct mid8250 *mid, struct uart_port *p)
 	return 0;
 }
 
+static void pnw_exit(struct mid8250 *mid)
+{
+	pci_dev_put(mid->dma_dev);
+}
+
 static int tng_handle_irq(struct uart_port *p)
 {
 	struct mid8250 *mid = p->private_data;
@@ -124,6 +129,11 @@ static int tng_setup(struct mid8250 *mid, struct uart_port *p)
 	return 0;
 }
 
+static void tng_exit(struct mid8250 *mid)
+{
+	pci_dev_put(mid->dma_dev);
+}
+
 static int dnv_handle_irq(struct uart_port *p)
 {
 	struct mid8250 *mid = p->private_data;
@@ -330,9 +340,9 @@ static int mid8250_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 
 	pci_set_drvdata(pdev, mid);
 	return 0;
+
 err:
-	if (mid->board->exit)
-		mid->board->exit(mid);
+	mid->board->exit(mid);
 	return ret;
 }
 
@@ -342,8 +352,7 @@ static void mid8250_remove(struct pci_dev *pdev)
 
 	serial8250_unregister_port(mid->line);
 
-	if (mid->board->exit)
-		mid->board->exit(mid);
+	mid->board->exit(mid);
 }
 
 static const struct mid8250_board pnw_board = {
@@ -351,6 +360,7 @@ static const struct mid8250_board pnw_board = {
 	.freq = 50000000,
 	.base_baud = 115200,
 	.setup = pnw_setup,
+	.exit = pnw_exit,
 };
 
 static const struct mid8250_board tng_board = {
@@ -358,6 +368,7 @@ static const struct mid8250_board tng_board = {
 	.freq = 38400000,
 	.base_baud = 1843200,
 	.setup = tng_setup,
+	.exit = tng_exit,
 };
 
 static const struct mid8250_board dnv_board = {
diff --git a/drivers/tty/serial/8250/8250_of.c b/drivers/tty/serial/8250/8250_of.c
index 9ba31701a372..a9b0a84b1e43 100644
--- a/drivers/tty/serial/8250/8250_of.c
+++ b/drivers/tty/serial/8250/8250_of.c
@@ -105,8 +105,17 @@ static int of_platform_serial_setup(struct platform_device *ofdev,
 		port->mapsize = resource_size(&resource);
 
 		/* Check for shifted address mapping */
-		if (of_property_read_u32(np, "reg-offset", &prop) == 0)
+		if (of_property_read_u32(np, "reg-offset", &prop) == 0) {
+			if (prop >= port->mapsize) {
+				dev_warn(&ofdev->dev, "reg-offset %u exceeds region size %pa\n",
+					 prop, &port->mapsize);
+				ret = -EINVAL;
+				goto err_unprepare;
+			}
+
 			port->mapbase += prop;
+			port->mapsize -= prop;
+		}
 
 		port->iotype = UPIO_MEM;
 		if (of_property_read_u32(np, "reg-io-width", &prop) == 0) {
diff --git a/drivers/tty/serial/8250/8250_pci.c b/drivers/tty/serial/8250/8250_pci.c
index a2bb103f22fc..92e2ee278523 100644
--- a/drivers/tty/serial/8250/8250_pci.c
+++ b/drivers/tty/serial/8250/8250_pci.c
@@ -1351,29 +1351,33 @@ pericom_do_set_divisor(struct uart_port *port, unsigned int baud,
 {
 	int scr;
 	int lcr;
-	int actual_baud;
-	int tolerance;
 
-	for (scr = 5 ; scr <= 15 ; scr++) {
-		actual_baud = 921600 * 16 / scr;
-		tolerance = actual_baud / 50;
+	for (scr = 16; scr > 4; scr--) {
+		unsigned int maxrate = port->uartclk / scr;
+		unsigned int divisor = max(maxrate / baud, 1U);
+		int delta = maxrate / divisor - baud;
 
-		if ((baud < actual_baud + tolerance) &&
-			(baud > actual_baud - tolerance)) {
+		if (baud > maxrate + baud / 50)
+			continue;
 
+		if (delta > baud / 50)
+			divisor++;
+
+		if (divisor > 0xffff)
+			continue;
+
+		/* Update delta due to possible divisor change */
+		delta = maxrate / divisor - baud;
+		if (abs(delta) < baud / 50) {
 			lcr = serial_port_in(port, UART_LCR);
 			serial_port_out(port, UART_LCR, lcr | 0x80);
-
-			serial_port_out(port, UART_DLL, 1);
-			serial_port_out(port, UART_DLM, 0);
+			serial_port_out(port, UART_DLL, divisor & 0xff);
+			serial_port_out(port, UART_DLM, divisor >> 8 & 0xff);
 			serial_port_out(port, 2, 16 - scr);
 			serial_port_out(port, UART_LCR, lcr);
 			return;
-		} else if (baud > actual_baud) {
-			break;
 		}
 	}
-	serial8250_do_set_divisor(port, baud, quot, quot_frac);
 }
 static int pci_pericom_setup(struct serial_private *priv,
 		  const struct pciserial_board *board,
@@ -2285,7 +2289,7 @@ static struct pci_serial_quirk pci_serial_quirks[] __refdata = {
 		.setup      = pci_pericom_setup_four_at_eight,
 	},
 	{
-		.vendor     = PCI_DEVICE_ID_ACCESIO_PCIE_ICM_4S,
+		.vendor     = PCI_VENDOR_ID_ACCESIO,
 		.device     = PCI_DEVICE_ID_ACCESIO_PCIE_ICM232_4,
 		.subvendor  = PCI_ANY_ID,
 		.subdevice  = PCI_ANY_ID,
@@ -2293,6 +2297,13 @@ static struct pci_serial_quirk pci_serial_quirks[] __refdata = {
 	},
 	{
 		.vendor     = PCI_VENDOR_ID_ACCESIO,
+		.device     = PCI_DEVICE_ID_ACCESIO_PCIE_ICM_4S,
+		.subvendor  = PCI_ANY_ID,
+		.subdevice  = PCI_ANY_ID,
+		.setup      = pci_pericom_setup_four_at_eight,
+	},
+	{
+		.vendor     = PCI_VENDOR_ID_ACCESIO,
 		.device     = PCI_DEVICE_ID_ACCESIO_MPCIE_ICM232_4,
 		.subvendor  = PCI_ANY_ID,
 		.subdevice  = PCI_ANY_ID,
@@ -2896,7 +2907,7 @@ enum pci_board_num_t {
 	pbn_panacom2,
 	pbn_panacom4,
 	pbn_plx_romulus,
-	pbn_endrun_2_4000000,
+	pbn_endrun_2_3906250,
 	pbn_oxsemi,
 	pbn_oxsemi_1_4000000,
 	pbn_oxsemi_2_4000000,
@@ -3423,10 +3434,10 @@ static struct pciserial_board pci_boards[] = {
 	* signal now many ports are available
 	* 2 port 952 Uart support
 	*/
-	[pbn_endrun_2_4000000] = {
+	[pbn_endrun_2_3906250] = {
 		.flags		= FL_BASE0,
 		.num_ports	= 2,
-		.base_baud	= 4000000,
+		.base_baud	= 3906250,
 		.uart_offset	= 0x200,
 		.first_offset	= 0x1000,
 	},
@@ -4334,7 +4345,7 @@ static const struct pci_device_id serial_pci_tbl[] = {
 	*/
 	{	PCI_VENDOR_ID_ENDRUN, PCI_DEVICE_ID_ENDRUN_1588,
 		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
-		pbn_endrun_2_4000000 },
+		pbn_endrun_2_3906250 },
 	/*
 	 * Quatech cards. These actually have configurable clocks but for
 	 * now we just use the default.
@@ -5119,8 +5130,30 @@ static const struct pci_device_id serial_pci_tbl[] = {
 	{	PCI_VENDOR_ID_INTASHIELD, PCI_DEVICE_ID_INTASHIELD_IS400,
 		PCI_ANY_ID, PCI_ANY_ID, 0, 0,    /* 135a.0dc0 */
 		pbn_b2_4_115200 },
+	/* Brainboxes Devices */
+	/*
+	* Brainboxes UC-101
+	*/
+	{       PCI_VENDOR_ID_INTASHIELD, 0x0BA1,
+		PCI_ANY_ID, PCI_ANY_ID,
+		0, 0,
+		pbn_b2_2_115200 },
 	/*
-	 * BrainBoxes UC-260
+	 * Brainboxes UC-235/246
+	 */
+	{	PCI_VENDOR_ID_INTASHIELD, 0x0AA1,
+		PCI_ANY_ID, PCI_ANY_ID,
+		0, 0,
+		pbn_b2_1_115200 },
+	/*
+	 * Brainboxes UC-257
+	 */
+	{	PCI_VENDOR_ID_INTASHIELD, 0x0861,
+		PCI_ANY_ID, PCI_ANY_ID,
+		0, 0,
+		pbn_b2_2_115200 },
+	/*
+	 * Brainboxes UC-260/271/701/756
 	 */
 	{	PCI_VENDOR_ID_INTASHIELD, 0x0D21,
 		PCI_ANY_ID, PCI_ANY_ID,
@@ -5128,7 +5161,81 @@ static const struct pci_device_id serial_pci_tbl[] = {
 		pbn_b2_4_115200 },
 	{	PCI_VENDOR_ID_INTASHIELD, 0x0E34,
 		PCI_ANY_ID, PCI_ANY_ID,
-		 PCI_CLASS_COMMUNICATION_MULTISERIAL << 8, 0xffff00,
+		PCI_CLASS_COMMUNICATION_MULTISERIAL << 8, 0xffff00,
+		pbn_b2_4_115200 },
+	/*
+	 * Brainboxes UC-268
+	 */
+	{       PCI_VENDOR_ID_INTASHIELD, 0x0841,
+		PCI_ANY_ID, PCI_ANY_ID,
+		0, 0,
+		pbn_b2_4_115200 },
+	/*
+	 * Brainboxes UC-275/279
+	 */
+	{	PCI_VENDOR_ID_INTASHIELD, 0x0881,
+		PCI_ANY_ID, PCI_ANY_ID,
+		0, 0,
+		pbn_b2_8_115200 },
+	/*
+	 * Brainboxes UC-302
+	 */
+	{	PCI_VENDOR_ID_INTASHIELD, 0x08E1,
+		PCI_ANY_ID, PCI_ANY_ID,
+		0, 0,
+		pbn_b2_2_115200 },
+	/*
+	 * Brainboxes UC-310
+	 */
+	{       PCI_VENDOR_ID_INTASHIELD, 0x08C1,
+		PCI_ANY_ID, PCI_ANY_ID,
+		0, 0,
+		pbn_b2_2_115200 },
+	/*
+	 * Brainboxes UC-313
+	 */
+	{       PCI_VENDOR_ID_INTASHIELD, 0x08A3,
+		PCI_ANY_ID, PCI_ANY_ID,
+		0, 0,
+		pbn_b2_2_115200 },
+	/*
+	 * Brainboxes UC-320/324
+	 */
+	{	PCI_VENDOR_ID_INTASHIELD, 0x0A61,
+		PCI_ANY_ID, PCI_ANY_ID,
+		0, 0,
+		pbn_b2_1_115200 },
+	/*
+	 * Brainboxes UC-346
+	 */
+	{	PCI_VENDOR_ID_INTASHIELD, 0x0B02,
+		PCI_ANY_ID, PCI_ANY_ID,
+		0, 0,
+		pbn_b2_4_115200 },
+	/*
+	 * Brainboxes UC-357
+	 */
+	{	PCI_VENDOR_ID_INTASHIELD, 0x0A81,
+		PCI_ANY_ID, PCI_ANY_ID,
+		0, 0,
+		pbn_b2_2_115200 },
+	{	PCI_VENDOR_ID_INTASHIELD, 0x0A83,
+		PCI_ANY_ID, PCI_ANY_ID,
+		0, 0,
+		pbn_b2_2_115200 },
+	/*
+	 * Brainboxes UC-368
+	 */
+	{	PCI_VENDOR_ID_INTASHIELD, 0x0C41,
+		PCI_ANY_ID, PCI_ANY_ID,
+		0, 0,
+		pbn_b2_4_115200 },
+	/*
+	 * Brainboxes UC-420/431
+	 */
+	{       PCI_VENDOR_ID_INTASHIELD, 0x0921,
+		PCI_ANY_ID, PCI_ANY_ID,
+		0, 0,
 		pbn_b2_4_115200 },
 	/*
 	 * Perle PCI-RAS cards
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 777ef1a9591c..c1891c55897a 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -1545,6 +1545,18 @@ static inline void start_tx_rs485(struct uart_port *port)
 	if (!(up->port.rs485.flags & SER_RS485_RX_DURING_TX))
 		serial8250_stop_rx(&up->port);
 
+	/*
+	 * While serial8250_em485_handle_stop_tx() is a noop if
+	 * em485->active_timer != &em485->stop_tx_timer, it might happen that
+	 * the timer is still armed and triggers only after the current bunch of
+	 * chars is send and em485->active_timer == &em485->stop_tx_timer again.
+	 * So cancel the timer. There is still a theoretical race condition if
+	 * the timer is already running and only comes around to check for
+	 * em485->active_timer when &em485->stop_tx_timer is armed again.
+	 */
+	if (em485->active_timer == &em485->stop_tx_timer)
+		hrtimer_try_to_cancel(&em485->stop_tx_timer);
+
 	em485->active_timer = NULL;
 
 	mcr = serial8250_in_MCR(up);
@@ -3172,7 +3184,7 @@ static void serial8250_console_restore(struct uart_8250_port *up)
 
 	serial8250_set_divisor(port, baud, quot, frac);
 	serial_port_out(port, UART_LCR, up->lcr);
-	serial8250_out_MCR(up, UART_MCR_DTR | UART_MCR_RTS);
+	serial8250_out_MCR(up, up->mcr | UART_MCR_DTR | UART_MCR_RTS);
 }
 
 /*
diff --git a/drivers/tty/serial/amba-pl010.c b/drivers/tty/serial/amba-pl010.c
index 2c37d11726ab..13f882e5e7b7 100644
--- a/drivers/tty/serial/amba-pl010.c
+++ b/drivers/tty/serial/amba-pl010.c
@@ -452,14 +452,11 @@ pl010_set_termios(struct uart_port *port, struct ktermios *termios,
 	if ((termios->c_cflag & CREAD) == 0)
 		uap->port.ignore_status_mask |= UART_DUMMY_RSR_RX;
 
-	/* first, disable everything */
 	old_cr = readb(uap->port.membase + UART010_CR) & ~UART010_CR_MSIE;
 
 	if (UART_ENABLE_MS(port, termios->c_cflag))
 		old_cr |= UART010_CR_MSIE;
 
-	writel(0, uap->port.membase + UART010_CR);
-
 	/* Set baud rate */
 	quot -= 1;
 	writel((quot & 0xf00) >> 8, uap->port.membase + UART010_LCRM);
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 16720c97a4dd..0bd8c05d72d6 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -2095,31 +2095,12 @@ static const char *pl011_type(struct uart_port *port)
 }
 
 /*
- * Release the memory region(s) being used by 'port'
- */
-static void pl011_release_port(struct uart_port *port)
-{
-	release_mem_region(port->mapbase, SZ_4K);
-}
-
-/*
- * Request the memory region(s) being used by 'port'
- */
-static int pl011_request_port(struct uart_port *port)
-{
-	return request_mem_region(port->mapbase, SZ_4K, "uart-pl011")
-			!= NULL ? 0 : -EBUSY;
-}
-
-/*
  * Configure/autoconfigure the port.
  */
 static void pl011_config_port(struct uart_port *port, int flags)
 {
-	if (flags & UART_CONFIG_TYPE) {
+	if (flags & UART_CONFIG_TYPE)
 		port->type = PORT_AMBA;
-		pl011_request_port(port);
-	}
 }
 
 /*
@@ -2134,6 +2115,8 @@ static int pl011_verify_port(struct uart_port *port, struct serial_struct *ser)
 		ret = -EINVAL;
 	if (ser->baud_base < 9600)
 		ret = -EINVAL;
+	if (port->mapbase != (unsigned long) ser->iomem_base)
+		ret = -EINVAL;
 	return ret;
 }
 
@@ -2151,8 +2134,6 @@ static const struct uart_ops amba_pl011_pops = {
 	.flush_buffer	= pl011_dma_flush_buffer,
 	.set_termios	= pl011_set_termios,
 	.type		= pl011_type,
-	.release_port	= pl011_release_port,
-	.request_port	= pl011_request_port,
 	.config_port	= pl011_config_port,
 	.verify_port	= pl011_verify_port,
 #ifdef CONFIG_CONSOLE_POLL
@@ -2182,8 +2163,6 @@ static const struct uart_ops sbsa_uart_pops = {
 	.shutdown	= sbsa_uart_shutdown,
 	.set_termios	= sbsa_uart_set_termios,
 	.type		= pl011_type,
-	.release_port	= pl011_release_port,
-	.request_port	= pl011_request_port,
 	.config_port	= pl011_config_port,
 	.verify_port	= pl011_verify_port,
 #ifdef CONFIG_CONSOLE_POLL
@@ -2770,6 +2749,7 @@ MODULE_DEVICE_TABLE(of, sbsa_uart_of_match);
 
 static const struct acpi_device_id sbsa_uart_acpi_match[] = {
 	{ "ARMH0011", 0 },
+	{ "ARMHB000", 0 },
 	{},
 };
 MODULE_DEVICE_TABLE(acpi, sbsa_uart_acpi_match);
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index 8a909d556185..3b2c25bd2e06 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -1002,6 +1002,13 @@ static void atmel_tx_dma(struct uart_port *port)
 		desc->callback = atmel_complete_tx_dma;
 		desc->callback_param = atmel_port;
 		atmel_port->cookie_tx = dmaengine_submit(desc);
+		if (dma_submit_error(atmel_port->cookie_tx)) {
+			dev_err(port->dev, "dma_submit_error %d\n",
+				atmel_port->cookie_tx);
+			return;
+		}
+
+		dma_async_issue_pending(chan);
 	}
 
 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
@@ -1262,6 +1269,13 @@ static int atmel_prepare_rx_dma(struct uart_port *port)
 	desc->callback_param = port;
 	atmel_port->desc_rx = desc;
 	atmel_port->cookie_rx = dmaengine_submit(desc);
+	if (dma_submit_error(atmel_port->cookie_rx)) {
+		dev_err(port->dev, "dma_submit_error %d\n",
+			atmel_port->cookie_rx);
+		goto chan_err;
+	}
+
+	dma_async_issue_pending(atmel_port->chan_rx);
 
 	return 0;
 
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index dd92afdee2d2..c72a7cda4638 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -1425,7 +1425,7 @@ static int imx_uart_startup(struct uart_port *port)
 	imx_uart_writel(sport, ucr1, UCR1);
 
 	ucr4 = imx_uart_readl(sport, UCR4) & ~UCR4_OREN;
-	if (!sport->dma_is_enabled)
+	if (!dma_is_inited)
 		ucr4 |= UCR4_OREN;
 	imx_uart_writel(sport, ucr4, UCR4);
 
diff --git a/drivers/tty/serial/kgdboc.c b/drivers/tty/serial/kgdboc.c
index f5608ad68ae1..6d4792ec9e5f 100644
--- a/drivers/tty/serial/kgdboc.c
+++ b/drivers/tty/serial/kgdboc.c
@@ -391,16 +391,16 @@ static int kgdboc_option_setup(char *opt)
 {
 	if (!opt) {
 		pr_err("config string not provided\n");
-		return -EINVAL;
+		return 1;
 	}
 
 	if (strlen(opt) >= MAX_CONFIG_LEN) {
 		pr_err("config string too long\n");
-		return -ENOSPC;
+		return 1;
 	}
 	strcpy(config, opt);
 
-	return 0;
+	return 1;
 }
 
 __setup("kgdboc=", kgdboc_option_setup);
diff --git a/drivers/tty/serial/msm_serial.c b/drivers/tty/serial/msm_serial.c
index e0718ee5d42a..5129c2dfbe07 100644
--- a/drivers/tty/serial/msm_serial.c
+++ b/drivers/tty/serial/msm_serial.c
@@ -603,6 +603,9 @@ static void msm_start_rx_dma(struct msm_port *msm_port)
 	u32 val;
 	int ret;
 
+	if (IS_ENABLED(CONFIG_CONSOLE_POLL))
+		return;
+
 	if (!dma->chan)
 		return;
 
diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c
index c7683beb3412..6040d5a6139a 100644
--- a/drivers/tty/serial/samsung.c
+++ b/drivers/tty/serial/samsung.c
@@ -761,11 +761,8 @@ static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id)
 		goto out;
 	}
 
-	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) {
-		spin_unlock(&port->lock);
+	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 		uart_write_wakeup(port);
-		spin_lock(&port->lock);
-	}
 
 	if (uart_circ_empty(xmit))
 		s3c24xx_serial_stop_tx(port);
diff --git a/drivers/tty/serial/serial-tegra.c b/drivers/tty/serial/serial-tegra.c
index 64f18bf1e694..74c21152367a 100644
--- a/drivers/tty/serial/serial-tegra.c
+++ b/drivers/tty/serial/serial-tegra.c
@@ -1494,7 +1494,7 @@ static struct tegra_uart_chip_data tegra20_uart_chip_data = {
 	.fifo_mode_enable_status	= false,
 	.uart_max_port			= 5,
 	.max_dma_burst_bytes		= 4,
-	.error_tolerance_low_range	= 0,
+	.error_tolerance_low_range	= -4,
 	.error_tolerance_high_range	= 4,
 };
 
@@ -1505,7 +1505,7 @@ static struct tegra_uart_chip_data tegra30_uart_chip_data = {
 	.fifo_mode_enable_status	= false,
 	.uart_max_port			= 5,
 	.max_dma_burst_bytes		= 4,
-	.error_tolerance_low_range	= 0,
+	.error_tolerance_low_range	= -4,
 	.error_tolerance_high_range	= 4,
 };
 
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 38ee13bbcab8..7cc7bd8aca0f 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -160,7 +160,7 @@ static void uart_port_dtr_rts(struct uart_port *uport, int raise)
 	int RTS_after_send = !!(uport->rs485.flags & SER_RS485_RTS_AFTER_SEND);
 
 	if (raise) {
-		if (rs485_on && !RTS_after_send) {
+		if (rs485_on && RTS_after_send) {
 			uart_set_mctrl(uport, TIOCM_DTR);
 			uart_clear_mctrl(uport, TIOCM_RTS);
 		} else {
@@ -169,7 +169,7 @@ static void uart_port_dtr_rts(struct uart_port *uport, int raise)
 	} else {
 		unsigned int clear = TIOCM_DTR;
 
-		clear |= (!rs485_on || !RTS_after_send) ? TIOCM_RTS : 0;
+		clear |= (!rs485_on || RTS_after_send) ? TIOCM_RTS : 0;
 		uart_clear_mctrl(uport, clear);
 	}
 }
@@ -1573,6 +1573,7 @@ static void uart_tty_port_shutdown(struct tty_port *port)
 {
 	struct uart_state *state = container_of(port, struct uart_state, port);
 	struct uart_port *uport = uart_port_check(state);
+	char *buf;
 
 	/*
 	 * At this point, we stop accepting input.  To do this, we
@@ -1594,8 +1595,18 @@ static void uart_tty_port_shutdown(struct tty_port *port)
 	 */
 	tty_port_set_suspended(port, 0);
 
-	uart_change_pm(state, UART_PM_STATE_OFF);
+	/*
+	 * Free the transmit buffer.
+	 */
+	spin_lock_irq(&uport->lock);
+	buf = state->xmit.buf;
+	state->xmit.buf = NULL;
+	spin_unlock_irq(&uport->lock);
+
+	if (buf)
+		free_page((unsigned long)buf);
 
+	uart_change_pm(state, UART_PM_STATE_OFF);
 }
 
 static void uart_wait_until_sent(struct tty_struct *tty, int timeout)
@@ -2384,7 +2395,8 @@ uart_configure_port(struct uart_driver *drv, struct uart_state *state,
 		 * We probably don't need a spinlock around this, but
 		 */
 		spin_lock_irqsave(&port->lock, flags);
-		port->ops->set_mctrl(port, port->mctrl & TIOCM_DTR);
+		port->mctrl &= TIOCM_DTR;
+		port->ops->set_mctrl(port, port->mctrl);
 		spin_unlock_irqrestore(&port->lock, flags);
 
 		/*
diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c
index 23b7bdae173c..d517b911cd04 100644
--- a/drivers/tty/serial/stm32-usart.c
+++ b/drivers/tty/serial/stm32-usart.c
@@ -536,7 +536,7 @@ static void stm32_start_tx(struct uart_port *port)
 {
 	struct circ_buf *xmit = &port->state->xmit;
 
-	if (uart_circ_empty(xmit))
+	if (uart_circ_empty(xmit) && !port->x_char)
 		return;
 
 	stm32_transmit_chars(port);
diff --git a/drivers/tty/serial/uartlite.c b/drivers/tty/serial/uartlite.c
index 56066d93a65b..9a4049c894f7 100644
--- a/drivers/tty/serial/uartlite.c
+++ b/drivers/tty/serial/uartlite.c
@@ -618,7 +618,7 @@ static struct uart_driver ulite_uart_driver = {
  *
  * Returns: 0 on success, <0 otherwise
  */
-static int ulite_assign(struct device *dev, int id, u32 base, int irq,
+static int ulite_assign(struct device *dev, int id, phys_addr_t base, int irq,
 			struct uartlite_data *pdata)
 {
 	struct uart_port *port;