Merge tag 'tty-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver updates from Greg KH:
 "Here is the big tty and serial driver pull request for 4.19-rc1.

  It's not all that big, just a number of small serial driver updates
  and fixes, along with some better vt handling for unicode characters
  for those using braille terminals.

  All of these patches have been in linux-next for a long time with no
  reported issues"

* tag 'tty-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (73 commits)
  tty: serial: 8250: Revert NXP SC16C2552 workaround
  serial: 8250_exar: Read INT0 from slave device, too
  tty: rocket: Fix possible buffer overwrite on register_PCI
  serial: 8250_dw: Add ACPI support for uart on Broadcom SoC
  serial: 8250_dw: always set baud rate in dw8250_set_termios
  dt-bindings: serial: Add binding for uartlite
  tty: serial: uartlite: Add support for suspend and resume
  tty: serial: uartlite: Add clock adaptation
  tty: serial: uartlite: Add structure for private data
  serial: sh-sci: Improve support for separate TEI and DRI interrupts
  serial: sh-sci: Remove SCIx_RZ_SCIFA_REGTYPE
  serial: sh-sci: Allow for compressed SCIF address
  serial: sh-sci: Improve interrupts description
  serial: 8250: Use cached port name directly in messages
  serial: 8250_exar: Drop unused variable in pci_xr17v35x_setup()
  vt: drop unused struct vt_struct
  vt: avoid a VLA in the unicode screen scroll function
  vt: add /dev/vcsu* to devices.txt
  vt: coherence validation code for the unicode screen buffer
  vt: selection: take screen contents from uniscr if available
  ...

44 files changed, 1381 insertions, 338 deletions

diff --git a/Documentation/admin-guide/devices.txt b/Documentation/admin-guide/devices.txt
index 4ec843123cc3..1649117e6087 100644
--- a/Documentation/admin-guide/devices.txt
+++ b/Documentation/admin-guide/devices.txt
@@ -173,14 +173,18 @@
 		they are redirected through the parport multiplex layer.
 
    7 char	Virtual console capture devices
-		  0 = /dev/vcs		Current vc text contents
-		  1 = /dev/vcs1		tty1 text contents
+		  0 = /dev/vcs		Current vc text (glyph) contents
+		  1 = /dev/vcs1		tty1 text (glyph) contents
 		    ...
-		 63 = /dev/vcs63	tty63 text contents
-		128 = /dev/vcsa		Current vc text/attribute contents
-		129 = /dev/vcsa1	tty1 text/attribute contents
+		 63 = /dev/vcs63	tty63 text (glyph) contents
+		 64 = /dev/vcsu		Current vc text (unicode) contents
+		65 = /dev/vcsu1		tty1 text (unicode) contents
 		    ...
-		191 = /dev/vcsa63	tty63 text/attribute contents
+		127 = /dev/vcsu63	tty63 text (unicode) contents
+		128 = /dev/vcsa		Current vc text/attribute (glyph) contents
+		129 = /dev/vcsa1	tty1 text/attribute (glyph) contents
+		    ...
+		191 = /dev/vcsa63	tty63 text/attribute (glyph) contents
 
 		NOTE: These devices permit both read and write access.
 
diff --git a/Documentation/devicetree/bindings/arm/mediatek.txt b/Documentation/devicetree/bindings/arm/mediatek.txt
index 7d21ab37c19c..48fac4ec91fc 100644
--- a/Documentation/devicetree/bindings/arm/mediatek.txt
+++ b/Documentation/devicetree/bindings/arm/mediatek.txt
@@ -11,6 +11,7 @@ compatible: Must contain one of
    "mediatek,mt6589"
    "mediatek,mt6592"
    "mediatek,mt6755"
+   "mediatek,mt6765"
    "mediatek,mt6795"
    "mediatek,mt6797"
    "mediatek,mt7622"
@@ -41,6 +42,9 @@ Supported boards:
 - Evaluation phone for MT6755(Helio P10):
     Required root node properties:
       - compatible = "mediatek,mt6755-evb", "mediatek,mt6755";
+- Evaluation board for MT6765(Helio P22):
+    Required root node properties:
+      - compatible = "mediatek,mt6765-evb", "mediatek,mt6765";
 - Evaluation board for MT6795(Helio X10):
     Required root node properties:
       - compatible = "mediatek,mt6795-evb", "mediatek,mt6795";
diff --git a/Documentation/devicetree/bindings/interrupt-controller/mediatek,sysirq.txt b/Documentation/devicetree/bindings/interrupt-controller/mediatek,sysirq.txt
index 6a32922a55b8..33a98eb44949 100644
--- a/Documentation/devicetree/bindings/interrupt-controller/mediatek,sysirq.txt
+++ b/Documentation/devicetree/bindings/interrupt-controller/mediatek,sysirq.txt
@@ -11,6 +11,7 @@ Required properties:
 	"mediatek,mt7622-sysirq", "mediatek,mt6577-sysirq": for MT7622
 	"mediatek,mt6795-sysirq", "mediatek,mt6577-sysirq": for MT6795
 	"mediatek,mt6797-sysirq", "mediatek,mt6577-sysirq": for MT6797
+	"mediatek,mt6765-sysirq", "mediatek,mt6577-sysirq": for MT6765
 	"mediatek,mt6755-sysirq", "mediatek,mt6577-sysirq": for MT6755
 	"mediatek,mt6592-sysirq", "mediatek,mt6577-sysirq": for MT6592
 	"mediatek,mt6589-sysirq", "mediatek,mt6577-sysirq": for MT6589
diff --git a/Documentation/devicetree/bindings/serial/fsl-imx-uart.txt b/Documentation/devicetree/bindings/serial/fsl-imx-uart.txt
index afcfbc34e243..35957cbf1571 100644
--- a/Documentation/devicetree/bindings/serial/fsl-imx-uart.txt
+++ b/Documentation/devicetree/bindings/serial/fsl-imx-uart.txt
@@ -9,7 +9,11 @@ Optional properties:
 - fsl,dte-mode : Indicate the uart works in DTE mode. The uart works
                   in DCE mode by default.
 - rs485-rts-delay, rs485-rts-active-low, rs485-rx-during-tx,
-  linux,rs485-enabled-at-boot-time: see rs485.txt
+  linux,rs485-enabled-at-boot-time: see rs485.txt. Note that for RS485
+  you must enable either the "uart-has-rtscts" or the "rts-gpios"
+  properties. In case you use "uart-has-rtscts" the signal that controls
+  the transceiver is actually CTS_B, not RTS_B. CTS_B is always output,
+  and RTS_B is input, regardless of dte-mode.
 
 Please check Documentation/devicetree/bindings/serial/serial.txt
 for the complete list of generic properties.
diff --git a/Documentation/devicetree/bindings/serial/mtk-uart.txt b/Documentation/devicetree/bindings/serial/mtk-uart.txt
index f73abff3de43..742cb470595b 100644
--- a/Documentation/devicetree/bindings/serial/mtk-uart.txt
+++ b/Documentation/devicetree/bindings/serial/mtk-uart.txt
@@ -8,6 +8,7 @@ Required properties:
   * "mediatek,mt6582-uart" for MT6582 compatible UARTS
   * "mediatek,mt6589-uart" for MT6589 compatible UARTS
   * "mediatek,mt6755-uart" for MT6755 compatible UARTS
+  * "mediatek,mt6765-uart" for MT6765 compatible UARTS
   * "mediatek,mt6795-uart" for MT6795 compatible UARTS
   * "mediatek,mt6797-uart" for MT6797 compatible UARTS
   * "mediatek,mt7622-uart" for MT7622 compatible UARTS
diff --git a/Documentation/devicetree/bindings/serial/omap_serial.txt b/Documentation/devicetree/bindings/serial/omap_serial.txt
index 4b0f05adb228..c35d5ece1156 100644
--- a/Documentation/devicetree/bindings/serial/omap_serial.txt
+++ b/Documentation/devicetree/bindings/serial/omap_serial.txt
@@ -1,6 +1,7 @@
 OMAP UART controller
 
 Required properties:
+- compatible : should be "ti,am654-uart" for AM654 controllers
 - compatible : should be "ti,omap2-uart" for OMAP2 controllers
 - compatible : should be "ti,omap3-uart" for OMAP3 controllers
 - compatible : should be "ti,omap4-uart" for OMAP4 controllers
diff --git a/Documentation/devicetree/bindings/serial/renesas,rzn1-uart.txt b/Documentation/devicetree/bindings/serial/renesas,rzn1-uart.txt
new file mode 100644
index 000000000000..8b9e0d4dc2e4
--- /dev/null
+++ b/Documentation/devicetree/bindings/serial/renesas,rzn1-uart.txt
@@ -0,0 +1,10 @@
+Renesas RZ/N1 UART
+
+This controller is based on the Synopsys DesignWare ABP UART and inherits all
+properties defined in snps-dw-apb-uart.txt except for the compatible property.
+
+Required properties:
+- compatible : The device specific string followed by the generic RZ/N1 string.
+   Therefore it must be one of:
+   "renesas,r9a06g032-uart", "renesas,rzn1-uart"
+   "renesas,r9a06g033-uart", "renesas,rzn1-uart"
diff --git a/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt b/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt
index 106808b55b6d..eaca9da79d83 100644
--- a/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt
+++ b/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt
@@ -5,6 +5,7 @@ Required properties:
   - compatible: Must contain one or more of the following:
 
     - "renesas,scif-r7s72100" for R7S72100 (RZ/A1H) SCIF compatible UART.
+    - "renesas,scif-r7s9210" for R7S9210 (RZ/A2) SCIF compatible UART.
     - "renesas,scifa-r8a73a4" for R8A73A4 (R-Mobile APE6) SCIFA compatible UART.
     - "renesas,scifb-r8a73a4" for R8A73A4 (R-Mobile APE6) SCIFB compatible UART.
     - "renesas,scifa-r8a7740" for R8A7740 (R-Mobile A1) SCIFA compatible UART.
@@ -72,7 +73,21 @@ Required properties:
     family-specific and/or generic versions.
 
   - reg: Base address and length of the I/O registers used by the UART.
-  - interrupts: Must contain an interrupt-specifier for the SCIx interrupt.
+  - interrupts: Must contain one or more interrupt-specifiers for the SCIx.
+                If a single interrupt is expressed, then all events are
+                multiplexed into this single interrupt.
+
+                If multiple interrupts are provided by the hardware, the order
+                in which the interrupts are listed must match order below. Note
+                that some HW interrupt events may be muxed together resulting
+                in duplicate entries.
+                The interrupt order is as follows:
+                  1. Error (ERI)
+                  2. Receive buffer full (RXI)
+                  3. Transmit buffer empty (TXI)
+                  4. Break (BRI)
+                  5. Data Ready (DRI)
+                  6. Transmit End (TEI)
 
   - clocks: Must contain a phandle and clock-specifier pair for each entry
     in clock-names.
@@ -89,7 +104,7 @@ Required properties:
       - "scif_clk" for the optional external clock source for the frequency
 	divider (SCIF_CLK).
 
-Note: Each enabled SCIx UART should have an alias correctly numbered in the
+Note: Each enabled SCIx UART may have an optional "serialN" alias in the
 "aliases" node.
 
 Optional properties:
diff --git a/Documentation/devicetree/bindings/serial/xlnx,opb-uartlite.txt b/Documentation/devicetree/bindings/serial/xlnx,opb-uartlite.txt
new file mode 100644
index 000000000000..c37deb44dead
--- /dev/null
+++ b/Documentation/devicetree/bindings/serial/xlnx,opb-uartlite.txt
@@ -0,0 +1,23 @@
+Xilinx Axi Uartlite controller Device Tree Bindings
+---------------------------------------------------------
+
+Required properties:
+- compatible		: Can be either of
+				"xlnx,xps-uartlite-1.00.a"
+				"xlnx,opb-uartlite-1.00.b"
+- reg			: Physical base address and size of the Axi Uartlite
+			  registers map.
+- interrupts		: Should contain the UART controller interrupt.
+
+Optional properties:
+- port-number		: Set Uart port number
+- clock-names		: Should be "s_axi_aclk"
+- clocks		: Input clock specifier. Refer to common clock bindings.
+
+Example:
+serial@800c0000 {
+	compatible = "xlnx,xps-uartlite-1.00.a";
+	reg = <0x0 0x800c0000 0x10000>;
+	interrupts = <0x0 0x6e 0x1>;
+	port-number = <0>;
+};
diff --git a/Documentation/devicetree/bindings/soc/qcom/qcom,geni-se.txt b/Documentation/devicetree/bindings/soc/qcom/qcom,geni-se.txt
index 68b7d6207e3d..ff92e5a41bed 100644
--- a/Documentation/devicetree/bindings/soc/qcom/qcom,geni-se.txt
+++ b/Documentation/devicetree/bindings/soc/qcom/qcom,geni-se.txt
@@ -46,7 +46,7 @@ Child nodes should conform to I2C bus binding as described in i2c.txt.
 Qualcomm Technologies Inc. GENI Serial Engine based UART Controller
 
 Required properties:
-- compatible:		Must be "qcom,geni-debug-uart".
+- compatible:		Must be "qcom,geni-debug-uart" or "qcom,geni-uart".
 - reg: 			Must contain UART register location and length.
 - interrupts: 		Must contain UART core interrupts.
 - clock-names:		Must contain "se".
diff --git a/drivers/parport/parport_serial.c b/drivers/parport/parport_serial.c
index ae9e01ef7599..461fd8a24278 100644
--- a/drivers/parport/parport_serial.c
+++ b/drivers/parport/parport_serial.c
@@ -58,6 +58,7 @@ enum parport_pc_pci_cards {
 	timedia_9079c,
 	wch_ch353_1s1p,
 	wch_ch353_2s1p,
+	wch_ch382_0s1p,
 	wch_ch382_2s1p,
 	brainboxes_5s1p,
 	sunix_2s1p,
@@ -147,6 +148,7 @@ static struct parport_pc_pci cards[] = {
 	/* timedia_9079c */             { 1, { { 2, 3 }, } },
 	/* wch_ch353_1s1p*/             { 1, { { 1, -1}, } },
 	/* wch_ch353_2s1p*/             { 1, { { 2, -1}, } },
+	/* wch_ch382_0s1p*/		{ 1, { { 2, -1}, } },
 	/* wch_ch382_2s1p*/             { 1, { { 2, -1}, } },
 	/* brainboxes_5s1p */           { 1, { { 3, -1 }, } },
 	/* sunix_2s1p */                { 1, { { 3, -1 }, } },
@@ -252,6 +254,7 @@ static struct pci_device_id parport_serial_pci_tbl[] = {
 	/* WCH CARDS */
 	{ 0x4348, 0x5053, PCI_ANY_ID, PCI_ANY_ID, 0, 0, wch_ch353_1s1p},
 	{ 0x4348, 0x7053, 0x4348, 0x3253, 0, 0, wch_ch353_2s1p},
+	{ 0x1c00, 0x3050, 0x1c00, 0x3050, 0, 0, wch_ch382_0s1p},
 	{ 0x1c00, 0x3250, 0x1c00, 0x3250, 0, 0, wch_ch382_2s1p},
 
 	/* BrainBoxes PX272/PX306 MIO card */
@@ -494,6 +497,12 @@ static struct pciserial_board pci_parport_serial_boards[] = {
 		.base_baud      = 115200,
 		.uart_offset    = 8,
 	},
+	[wch_ch382_0s1p] = {
+		.flags          = FL_BASE0,
+		.num_ports      = 0,
+		.base_baud      = 115200,
+		.uart_offset    = 8,
+	},
 	[wch_ch382_2s1p] = {
 		.flags          = FL_BASE0,
 		.num_ports      = 2,
diff --git a/drivers/s390/char/keyboard.c b/drivers/s390/char/keyboard.c
index bbb3001b0961..567aedc03c76 100644
--- a/drivers/s390/char/keyboard.c
+++ b/drivers/s390/char/keyboard.c
@@ -39,8 +39,34 @@ static const int kbd_max_vals[] = {
 };
 static const int KBD_NR_TYPES = ARRAY_SIZE(kbd_max_vals);
 
-static unsigned char ret_diacr[NR_DEAD] = {
-	'`', '\'', '^', '~', '"', ','
+static const unsigned char ret_diacr[NR_DEAD] = {
+	'`',	/* dead_grave */
+	'\'',	/* dead_acute */
+	'^',	/* dead_circumflex */
+	'~',	/* dead_tilda */
+	'"',	/* dead_diaeresis */
+	',',	/* dead_cedilla */
+	'_',	/* dead_macron */
+	'U',	/* dead_breve */
+	'.',	/* dead_abovedot */
+	'*',	/* dead_abovering */
+	'=',	/* dead_doubleacute */
+	'c',	/* dead_caron */
+	'k',	/* dead_ogonek */
+	'i',	/* dead_iota */
+	'#',	/* dead_voiced_sound */
+	'o',	/* dead_semivoiced_sound */
+	'!',	/* dead_belowdot */
+	'?',	/* dead_hook */
+	'+',	/* dead_horn */
+	'-',	/* dead_stroke */
+	')',	/* dead_abovecomma */
+	'(',	/* dead_abovereversedcomma */
+	':',	/* dead_doublegrave */
+	'n',	/* dead_invertedbreve */
+	';',	/* dead_belowcomma */
+	'$',	/* dead_currency */
+	'@',	/* dead_greek */
 };
 
 /*
diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c
index b0e2c4847a5d..678406e0948b 100644
--- a/drivers/tty/pty.c
+++ b/drivers/tty/pty.c
@@ -625,7 +625,7 @@ int ptm_open_peer(struct file *master, struct tty_struct *tty, int flags)
 	if (tty->driver != ptm_driver)
 		return -EIO;
 
-	fd = get_unused_fd_flags(0);
+	fd = get_unused_fd_flags(flags);
 	if (fd < 0) {
 		retval = fd;
 		goto err;
diff --git a/drivers/tty/rocket.c b/drivers/tty/rocket.c
index bdd17d2aaafd..b121d8f8f3d7 100644
--- a/drivers/tty/rocket.c
+++ b/drivers/tty/rocket.c
@@ -1881,7 +1881,7 @@ static __init int register_PCI(int i, struct pci_dev *dev)
 	ByteIO_t UPCIRingInd = 0;
 
 	if (!dev || !pci_match_id(rocket_pci_ids, dev) ||
-	    pci_enable_device(dev))
+	    pci_enable_device(dev) || i >= NUM_BOARDS)
 		return 0;
 
 	rcktpt_io_addr[i] = pci_resource_start(dev, 0);
diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c
index 9e59f4788589..9db93f500b4e 100644
--- a/drivers/tty/serdev/core.c
+++ b/drivers/tty/serdev/core.c
@@ -13,6 +13,8 @@
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_runtime.h>
 #include <linux/serdev.h>
 #include <linux/slab.h>
 
@@ -143,11 +145,28 @@ EXPORT_SYMBOL_GPL(serdev_device_remove);
 int serdev_device_open(struct serdev_device *serdev)
 {
 	struct serdev_controller *ctrl = serdev->ctrl;
+	int ret;
 
 	if (!ctrl || !ctrl->ops->open)
 		return -EINVAL;
 
-	return ctrl->ops->open(ctrl);
+	ret = ctrl->ops->open(ctrl);
+	if (ret)
+		return ret;
+
+	ret = pm_runtime_get_sync(&ctrl->dev);
+	if (ret < 0) {
+		pm_runtime_put_noidle(&ctrl->dev);
+		goto err_close;
+	}
+
+	return 0;
+
+err_close:
+	if (ctrl->ops->close)
+		ctrl->ops->close(ctrl);
+
+	return ret;
 }
 EXPORT_SYMBOL_GPL(serdev_device_open);
 
@@ -158,6 +177,8 @@ void serdev_device_close(struct serdev_device *serdev)
 	if (!ctrl || !ctrl->ops->close)
 		return;
 
+	pm_runtime_put(&ctrl->dev);
+
 	ctrl->ops->close(ctrl);
 }
 EXPORT_SYMBOL_GPL(serdev_device_close);
@@ -330,8 +351,17 @@ EXPORT_SYMBOL_GPL(serdev_device_set_tiocm);
 static int serdev_drv_probe(struct device *dev)
 {
 	const struct serdev_device_driver *sdrv = to_serdev_device_driver(dev->driver);
+	int ret;
+
+	ret = dev_pm_domain_attach(dev, true);
+	if (ret)
+		return ret;
+
+	ret = sdrv->probe(to_serdev_device(dev));
+	if (ret)
+		dev_pm_domain_detach(dev, true);
 
-	return sdrv->probe(to_serdev_device(dev));
+	return ret;
 }
 
 static int serdev_drv_remove(struct device *dev)
@@ -339,6 +369,9 @@ static int serdev_drv_remove(struct device *dev)
 	const struct serdev_device_driver *sdrv = to_serdev_device_driver(dev->driver);
 	if (sdrv->remove)
 		sdrv->remove(to_serdev_device(dev));
+
+	dev_pm_domain_detach(dev, true);
+
 	return 0;
 }
 
@@ -416,6 +449,9 @@ struct serdev_controller *serdev_controller_alloc(struct device *parent,
 
 	dev_set_name(&ctrl->dev, "serial%d", id);
 
+	pm_runtime_no_callbacks(&ctrl->dev);
+	pm_suspend_ignore_children(&ctrl->dev, true);
+
 	dev_dbg(&ctrl->dev, "allocated controller 0x%p id %d\n", ctrl, id);
 	return ctrl;
 
@@ -547,20 +583,23 @@ int serdev_controller_add(struct serdev_controller *ctrl)
 	if (ret)
 		return ret;
 
+	pm_runtime_enable(&ctrl->dev);
+
 	ret_of = of_serdev_register_devices(ctrl);
 	ret_acpi = acpi_serdev_register_devices(ctrl);
 	if (ret_of && ret_acpi) {
 		dev_dbg(&ctrl->dev, "no devices registered: of:%d acpi:%d\n",
 			ret_of, ret_acpi);
 		ret = -ENODEV;
-		goto out_dev_del;
+		goto err_rpm_disable;
 	}
 
 	dev_dbg(&ctrl->dev, "serdev%d registered: dev:%p\n",
 		ctrl->nr, &ctrl->dev);
 	return 0;
 
-out_dev_del:
+err_rpm_disable:
+	pm_runtime_disable(&ctrl->dev);
 	device_del(&ctrl->dev);
 	return ret;
 };
@@ -591,6 +630,7 @@ void serdev_controller_remove(struct serdev_controller *ctrl)
 
 	dummy = device_for_each_child(&ctrl->dev, NULL,
 				      serdev_remove_device);
+	pm_runtime_disable(&ctrl->dev);
 	device_del(&ctrl->dev);
 }
 EXPORT_SYMBOL_GPL(serdev_controller_remove);
diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
index 9342fc2ee7df..8fe3d0ed229e 100644
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c
@@ -323,7 +323,7 @@ static int univ8250_setup_irq(struct uart_8250_port *up)
 	 * the port is opened so this value needs to be preserved.
 	 */
 	if (up->bugs & UART_BUG_THRE) {
-		pr_debug("ttyS%d - using backup timer\n", serial_index(port));
+		pr_debug("%s - using backup timer\n", port->name);
 
 		up->timer.function = serial8250_backup_timeout;
 		mod_timer(&up->timer, jiffies +
@@ -1023,6 +1023,10 @@ int serial8250_register_8250_port(struct uart_8250_port *up)
 			uart->port.get_mctrl = up->port.get_mctrl;
 		if (up->port.set_mctrl)
 			uart->port.set_mctrl = up->port.set_mctrl;
+		if (up->port.get_divisor)
+			uart->port.get_divisor = up->port.get_divisor;
+		if (up->port.set_divisor)
+			uart->port.set_divisor = up->port.set_divisor;
 		if (up->port.startup)
 			uart->port.startup = up->port.startup;
 		if (up->port.shutdown)
diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index aff04f1de3a5..fa8dcb470640 100644
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -31,6 +31,7 @@
 
 /* Offsets for the DesignWare specific registers */
 #define DW_UART_USR	0x1f /* UART Status Register */
+#define DW_UART_DLF	0xc0 /* Divisor Latch Fraction Register */
 #define DW_UART_CPR	0xf4 /* Component Parameter Register */
 #define DW_UART_UCV	0xf8 /* UART Component Version */
 
@@ -55,6 +56,7 @@
 
 struct dw8250_data {
 	u8			usr_reg;
+	u8			dlf_size;
 	int			line;
 	int			msr_mask_on;
 	int			msr_mask_off;
@@ -67,6 +69,21 @@ struct dw8250_data {
 	unsigned int		uart_16550_compatible:1;
 };
 
+static inline u32 dw8250_readl_ext(struct uart_port *p, int offset)
+{
+	if (p->iotype == UPIO_MEM32BE)
+		return ioread32be(p->membase + offset);
+	return readl(p->membase + offset);
+}
+
+static inline void dw8250_writel_ext(struct uart_port *p, int offset, u32 reg)
+{
+	if (p->iotype == UPIO_MEM32BE)
+		iowrite32be(reg, p->membase + offset);
+	else
+		writel(reg, p->membase + offset);
+}
+
 static inline int dw8250_modify_msr(struct uart_port *p, int offset, int value)
 {
 	struct dw8250_data *d = p->private_data;
@@ -293,7 +310,7 @@ static void dw8250_set_termios(struct uart_port *p, struct ktermios *termios,
 	long rate;
 	int ret;
 
-	if (IS_ERR(d->clk) || !old)
+	if (IS_ERR(d->clk))
 		goto out;
 
 	clk_disable_unprepare(d->clk);
@@ -351,6 +368,37 @@ static bool dw8250_idma_filter(struct dma_chan *chan, void *param)
 	return param == chan->device->dev->parent;
 }
 
+/*
+ * divisor = div(I) + div(F)
+ * "I" means integer, "F" means fractional
+ * quot = div(I) = clk / (16 * baud)
+ * frac = div(F) * 2^dlf_size
+ *
+ * let rem = clk % (16 * baud)
+ * we have: div(F) * (16 * baud) = rem
+ * so frac = 2^dlf_size * rem / (16 * baud) = (rem << dlf_size) / (16 * baud)
+ */
+static unsigned int dw8250_get_divisor(struct uart_port *p,
+				       unsigned int baud,
+				       unsigned int *frac)
+{
+	unsigned int quot, rem, base_baud = baud * 16;
+	struct dw8250_data *d = p->private_data;
+
+	quot = p->uartclk / base_baud;
+	rem = p->uartclk % base_baud;
+	*frac = DIV_ROUND_CLOSEST(rem << d->dlf_size, base_baud);
+
+	return quot;
+}
+
+static void dw8250_set_divisor(struct uart_port *p, unsigned int baud,
+			       unsigned int quot, unsigned int quot_frac)
+{
+	dw8250_writel_ext(p, DW_UART_DLF, quot_frac);
+	serial8250_do_set_divisor(p, baud, quot, quot_frac);
+}
+
 static void dw8250_quirks(struct uart_port *p, struct dw8250_data *data)
 {
 	if (p->dev->of_node) {
@@ -404,20 +452,26 @@ static void dw8250_setup_port(struct uart_port *p)
 	 * If the Component Version Register returns zero, we know that
 	 * ADDITIONAL_FEATURES are not enabled. No need to go any further.
 	 */
-	if (p->iotype == UPIO_MEM32BE)
-		reg = ioread32be(p->membase + DW_UART_UCV);
-	else
-		reg = readl(p->membase + DW_UART_UCV);
+	reg = dw8250_readl_ext(p, DW_UART_UCV);
 	if (!reg)
 		return;
 
 	dev_dbg(p->dev, "Designware UART version %c.%c%c\n",
 		(reg >> 24) & 0xff, (reg >> 16) & 0xff, (reg >> 8) & 0xff);
 
-	if (p->iotype == UPIO_MEM32BE)
-		reg = ioread32be(p->membase + DW_UART_CPR);
-	else
-		reg = readl(p->membase + DW_UART_CPR);
+	dw8250_writel_ext(p, DW_UART_DLF, ~0U);
+	reg = dw8250_readl_ext(p, DW_UART_DLF);
+	dw8250_writel_ext(p, DW_UART_DLF, 0);
+
+	if (reg) {
+		struct dw8250_data *d = p->private_data;
+
+		d->dlf_size = fls(reg);
+		p->get_divisor = dw8250_get_divisor;
+		p->set_divisor = dw8250_set_divisor;
+	}
+
+	reg = dw8250_readl_ext(p, DW_UART_CPR);
 	if (!reg)
 		return;
 
@@ -693,6 +747,7 @@ static const struct of_device_id dw8250_of_match[] = {
 	{ .compatible = "snps,dw-apb-uart" },
 	{ .compatible = "cavium,octeon-3860-uart" },
 	{ .compatible = "marvell,armada-38x-uart" },
+	{ .compatible = "renesas,rzn1-uart" },
 	{ /* Sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, dw8250_of_match);
@@ -707,6 +762,7 @@ static const struct acpi_device_id dw8250_acpi_match[] = {
 	{ "APMC0D08", 0},
 	{ "AMD0020", 0 },
 	{ "AMDI0020", 0 },
+	{ "BRCM2032", 0 },
 	{ "HISI0031", 0 },
 	{ },
 };
diff --git a/drivers/tty/serial/8250/8250_exar.c b/drivers/tty/serial/8250/8250_exar.c
index 38af306ca0e8..0089aa305ef9 100644
--- a/drivers/tty/serial/8250/8250_exar.c
+++ b/drivers/tty/serial/8250/8250_exar.c
@@ -109,11 +109,12 @@ struct exar8250_platform {
  * struct exar8250_board - board information
  * @num_ports: number of serial ports
  * @reg_shift: describes UART register mapping in PCI memory
+ * @setup: quirk run at ->probe() stage
+ * @exit: quirk run at ->remove() stage<