Merge tag 'tty-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver updates from Greg KH:
 "Even in this age, people are still making new serial port silicon,
  why...

  Anyway, here's the TTY and Serial driver update for 5.4-rc1. Lots of
  changes in here for a number of embedded serial port devices that are
  being worked on because people really like to see those console
  logs...

  Other than that, nothing major here, no core tty changes that anyone
  should care about.

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

* tag 'tty-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (125 commits)
  serial: tegra: Add PIO mode support
  serial: tegra: report clk rate errors
  serial: tegra: add support to adjust baud rate
  serial: tegra: DT for Adjusted baud rates
  serial: tegra: add support to use 8 bytes trigger
  serial: tegra: set maximum num of uart ports to 8
  serial: tegra: check for FIFO mode enabled status
  dt-binding: serial: tegra: add new chips
  serial: tegra: report error to upper tty layer
  serial: tegra: flush the RX fifo on frame error
  serial: tegra: avoid reg access when clk disabled
  serial: tegra: add support to ignore read
  serial: sprd: correct the wrong sequence of arguments
  dt-bindings: serial: Convert riscv,sifive-serial to json-schema
  serial: max310x: turn off transmitter before activating AutoCTS or auto transmitter flow control
  serial: max310x: Properly set flags in AutoCTS mode
  tty: serial: fix platform_no_drv_owner.cocci warnings
  dt-bindings: serial: Document Freescale LINFlexD UART
  serial: fsl_linflexuart: Update compatible string
  tty: n_gsm: avoid recursive locking with async port hangup
  ...

7 files changed, 141 insertions, 45 deletions

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 6ef205fd7c97..782e9072407b 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -1094,6 +1094,12 @@
 			the framebuffer, pass the 'ram' option so that it is
 			mapped with the correct attributes.
 
+		linflex,<addr>
+			Use early console provided by Freescale LinFlex UART
+			serial driver for NXP S32V234 SoCs. A valid base
+			address must be provided, and the serial port must
+			already be setup and configured.
+
 	earlyprintk=	[X86,SH,ARM,M68k,S390]
 			earlyprintk=vga
 			earlyprintk=sclp
diff --git a/Documentation/devicetree/bindings/serial/fsl,s32-linflexuart.txt b/Documentation/devicetree/bindings/serial/fsl,s32-linflexuart.txt
new file mode 100644
index 000000000000..f1bbe0826be5
--- /dev/null
+++ b/Documentation/devicetree/bindings/serial/fsl,s32-linflexuart.txt
@@ -0,0 +1,22 @@
+* Freescale LINFlexD UART
+
+The LINFlexD controller implements several LIN protocol versions, as well as
+support for full-duplex UART communication through 8-bit and 9-bit frames.
+
+See chapter 47 ("LINFlexD") in the reference manual[1].
+
+Required properties:
+- compatible :
+  - "fsl,s32v234-linflexuart" for LINFlexD configured in UART mode, which
+    is compatible with the one integrated on S32V234 SoC
+- reg : Address and length of the register set for the device
+- interrupts : Should contain uart interrupt
+
+Example:
+uart0: serial@40053000 {
+	compatible = "fsl,s32v234-linflexuart";
+	reg = <0x0 0x40053000 0x0 0x1000>;
+	interrupts = <0 59 4>;
+};
+
+[1] https://www.nxp.com/webapp/Download?colCode=S32V234RM
diff --git a/Documentation/devicetree/bindings/serial/nvidia,tegra20-hsuart.txt b/Documentation/devicetree/bindings/serial/nvidia,tegra20-hsuart.txt
index d7edf732eb7f..f709304036c2 100644
--- a/Documentation/devicetree/bindings/serial/nvidia,tegra20-hsuart.txt
+++ b/Documentation/devicetree/bindings/serial/nvidia,tegra20-hsuart.txt
@@ -1,7 +1,12 @@
 NVIDIA Tegra20/Tegra30 high speed (DMA based) UART controller driver.
 
 Required properties:
-- compatible : should be "nvidia,tegra30-hsuart", "nvidia,tegra20-hsuart".
+- compatible : should be,
+  "nvidia,tegra20-hsuart" for Tegra20,
+  "nvidia,tegra30-hsuart" for Tegra30,
+  "nvidia,tegra186-hsuart" for Tegra186,
+  "nvidia,tegra194-hsuart" for Tegra194.
+
 - reg: Should contain UART controller registers location and length.
 - interrupts: Should contain UART controller interrupts.
 - clocks: Must contain one entry, for the module clock.
@@ -19,6 +24,37 @@ Required properties:
 Optional properties:
 - nvidia,enable-modem-interrupt: Enable modem interrupts. Should be enable
 		only if all 8 lines of UART controller are pinmuxed.
+- nvidia,adjust-baud-rates: List of entries providing percentage of baud rate
+  adjustment within a range.
+  Each entry contains sets of 3 values. Range low/high and adjusted rate.
+  <range_low range_high adjusted_rate>
+  When baud rate set on controller falls within the range mentioned in this
+  field, baud rate will be adjusted by percentage mentioned here.
+  Ex: <9600 115200 200>
+  Increase baud rate by 2% when set baud rate falls within range 9600 to 115200
+
+Baud Rate tolerance:
+  Standard UART devices are expected to have tolerance for baud rate error by
+  -4 to +4 %. All Tegra devices till Tegra210 had this support. However,
+  Tegra186 chip has a known hardware issue. UART Rx baud rate tolerance level
+  is 0% to +4% in 1-stop config. Otherwise, the received data will have
+  corruption/invalid framing errors. Parker errata suggests adjusting baud
+  rate to be higher than the deviations observed in Tx.
+
+  Tx deviation of connected device can be captured over scope (or noted from
+  its spec) for valid range and Tegra baud rate has to be set above actual
+  Tx baud rate observed. To do this we use nvidia,adjust-baud-rates
+
+  As an example, consider there is deviation observed in Tx for baud rates as
+  listed below.
+  0 to 9600 has 1% deviation
+  9600 to 115200 2% deviation
+  This slight deviation is expcted and Tegra UART is expected to handle it. Due
+  to the issue stated above, baud rate on Tegra UART should be set equal to or
+  above deviation observed for avoiding frame errors.
+  Property should be set like this
+  nvidia,adjust-baud-rates = <0 9600 100>,
+  			     <9600 115200 200>;
 
 Example:
 
@@ -33,4 +69,5 @@ serial@70006000 {
 	reset-names = "serial";
 	dmas = <&apbdma 8>, <&apbdma 8>;
 	dma-names = "rx", "tx";
+	nvidia,adjust-baud-rates = <1000000 4000000 136>; /* 1.36% shift */
 };
diff --git a/Documentation/devicetree/bindings/serial/sifive-serial.txt b/Documentation/devicetree/bindings/serial/sifive-serial.txt
deleted file mode 100644
index c86b1e524159..000000000000
--- a/Documentation/devicetree/bindings/serial/sifive-serial.txt
+++ /dev/null
@@ -1,33 +0,0 @@
-SiFive asynchronous serial interface (UART)
-
-Required properties:
-
-- compatible: should be something similar to
-	      "sifive,<chip>-uart" for the UART as integrated
-	      on a particular chip, and "sifive,uart<version>" for the
-	      general UART IP block programming model.	Supported
-	      compatible strings as of the date of this writing are:
-	      "sifive,fu540-c000-uart" for the SiFive UART v0 as
-	      integrated onto the SiFive FU540 chip, or "sifive,uart0"
-	      for the SiFive UART v0 IP block with no chip integration
-	      tweaks (if any)
-- reg: address and length of the register space
-- interrupts: Should contain the UART interrupt identifier
-- clocks: Should contain a clock identifier for the UART's parent clock
-
-
-UART HDL that corresponds to the IP block version numbers can be found
-here:
-
-https://github.com/sifive/sifive-blocks/tree/master/src/main/scala/devices/uart
-
-
-Example:
-
-uart0: serial@10010000 {
-	compatible = "sifive,fu540-c000-uart", "sifive,uart0";
-	interrupt-parent = <&plic0>;
-	interrupts = <80>;
-	reg = <0x0 0x10010000 0x0 0x1000>;
-	clocks = <&prci PRCI_CLK_TLCLK>;
-};
diff --git a/Documentation/devicetree/bindings/serial/sifive-serial.yaml b/Documentation/devicetree/bindings/serial/sifive-serial.yaml
new file mode 100644
index 000000000000..e8d3aeda1202
--- /dev/null
+++ b/Documentation/devicetree/bindings/serial/sifive-serial.yaml
@@ -0,0 +1,62 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/serial/sifive-serial.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: SiFive asynchronous serial interface (UART)
+
+maintainers:
+  - Pragnesh Patel <pragnesh.patel@sifive.com>
+  - Paul Walmsley  <paul.walmsley@sifive.com>
+  - Palmer Dabbelt <palmer@sifive.com>
+
+allOf:
+  - $ref: /schemas/serial.yaml#
+
+properties:
+  compatible:
+    items:
+      - const: sifive,fu540-c000-uart
+      - const: sifive,uart0
+
+    description:
+      Should be something similar to "sifive,<chip>-uart"
+      for the UART as integrated on a particular chip,
+      and "sifive,uart<version>" for the general UART IP
+      block programming model.
+
+      UART HDL that corresponds to the IP block version
+      numbers can be found here -
+
+      https://github.com/sifive/sifive-blocks/tree/master/src/main/scala/devices/uart
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - clocks
+
+additionalProperties: false
+
+examples:
+  - |
+      #include <dt-bindings/clock/sifive-fu540-prci.h>
+      serial@10010000 {
+        compatible = "sifive,fu540-c000-uart", "sifive,uart0";
+        interrupt-parent = <&plic0>;
+        interrupts = <80>;
+        reg = <0x0 0x10010000 0x0 0x1000>;
+        clocks = <&prci PRCI_CLK_TLCLK>;
+      };
+
+...
diff --git a/Documentation/devicetree/bindings/serial/st,stm32-usart.txt b/Documentation/devicetree/bindings/serial/st,stm32-usart.txt
index a6b19485c9dc..8620f7fcbd50 100644
--- a/Documentation/devicetree/bindings/serial/st,stm32-usart.txt
+++ b/Documentation/devicetree/bindings/serial/st,stm32-usart.txt
@@ -20,6 +20,11 @@ Optional properties:
   linux,rs485-enabled-at-boot-time: see rs485.txt.
 - dmas: phandle(s) to DMA controller node(s). Refer to stm32-dma.txt
 - dma-names: "rx" and/or "tx"
+- wakeup-source: bool flag to indicate this device has wakeup capabilities
+- interrupt-names, if optional wake-up interrupt is used, should be:
+  - "event": the name for the interrupt line of the USART instance
+  - "wakeup" the name for the optional wake-up interrupt
+
 
 Examples:
 usart4: serial@40004c00 {
diff --git a/Documentation/driver-api/serial/n_gsm.rst b/Documentation/driver-api/serial/n_gsm.rst
index f3ad9fd26408..286e7ff4d2d9 100644
--- a/Documentation/driver-api/serial/n_gsm.rst
+++ b/Documentation/driver-api/serial/n_gsm.rst
@@ -18,18 +18,22 @@ How to use it
 2. switch the serial line to using the n_gsm line discipline by using
    TIOCSETD ioctl,
 3. configure the mux using GSMIOC_GETCONF / GSMIOC_SETCONF ioctl,
+4. obtain base gsmtty number for the used serial port,
 
 Major parts of the initialization program :
 (a good starting point is util-linux-ng/sys-utils/ldattach.c)::
 
+  #include <stdio.h>
+  #include <stdint.h>
   #include <linux/gsmmux.h>
-  #define N_GSM0710	21	/* GSM 0710 Mux */
+  #include <linux/tty.h>
   #define DEFAULT_SPEED	B115200
   #define SERIAL_PORT	/dev/ttyS0
 
 	int ldisc = N_GSM0710;
 	struct gsm_config c;
 	struct termios configuration;
+	uint32_t first;
 
 	/* open the serial port connected to the modem */
 	fd = open(SERIAL_PORT, O_RDWR | O_NOCTTY | O_NDELAY);
@@ -58,21 +62,14 @@ Major parts of the initialization program :
 	c.mtu = 127;
 	/* set the new configuration */
 	ioctl(fd, GSMIOC_SETCONF, &c);
+	/* get first gsmtty device node */
+	ioctl(fd, GSMIOC_GETFIRST, &first);
+	printf("first muxed line: /dev/gsmtty%i\n", first);
 
 	/* and wait for ever to keep the line discipline enabled */
 	daemon(0,0);
 	pause();
 
-4. create the devices corresponding to the "virtual" serial ports (take care,
-   each modem has its configuration and some DLC have dedicated functions,
-   for example GPS), starting with minor 1 (DLC0 is reserved for the management
-   of the mux)::
-
-     MAJOR=`cat /proc/devices |grep gsmtty | awk '{print $1}`
-     for i in `seq 1 4`; do
-	mknod /dev/ttygsm$i c $MAJOR $i
-     done
-
 5. use these devices as plain serial ports.
 
    for example, it's possible: