Merge tag 'auxdisplay-for-linus-v5.11' of git://github.com/ojeda/linux

Pull auxdisplay updates from Miguel Ojeda:
 "A bigger set of changes than usual for auxdisplay. There have been
  quite a few changes in auxdisplay thanks to a refactor by Lars
  Poeschel to share code in order to introduce a new driver.

  Summary:

   - Significant refactor work to make charlcd independent of device,
     i.e. hd44780 (Lars Poeschel)

   - New driver: lcd2s (Lars Poeschel)

   - Fixes on top of the rework while being tested in -next (Lars
     Poeschel, Dan Carpenter and kernel test robot)"

* tag 'auxdisplay-for-linus-v5.11' of git://github.com/ojeda/linux: (30 commits)
  auxdisplay: panel: Remove redundant charlcd_ops structures
  auxdisplay: panel: Fix missing print function pointer
  auxdisplay: fix platform_no_drv_owner.cocci warnings
  auxdisplay: fix use after free in lcd2s_i2c_remove()
  auxdisplay: hd44780_common: Fix build error
  auxdisplay: add a driver for lcd2s character display
  auxdisplay: lcd2s DT binding doc
  auxdisplay: charlcd: Do not print chars at end of line
  auxdisplay: Change gotoxy calling interface
  auxdisplay: charlcd: replace last device specific stuff
  auxdisplay: hd44780: Remove clear_fast
  auxdisplay: hd44780_common: Reduce clear_display timeout
  auxdisplay: Call charlcd_backlight in place
  auxdisplay: Move char redefine code to hd44780_common
  auxdisplay: cleanup unnecessary hd44780 code in charlcd
  auxdisplay: implement various hd44780_common_ functions
  auxdisplay: Move init_display to hd44780_common
  auxdisplay: Make use of enum for backlight on / off
  auxdisplay: make charlcd_backlight visible to hd44780_common
  auxdisplay: Move clear_display to hd44780_common
  ...

Documentation/devicetree/bindings/auxdisplay/modtronix,lcd2s.yaml

@@ -0,0 +1,58 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/auxdisplay/modtronix,lcd2s.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Modtronix engineering LCD2S Character LCD Display
+
+maintainers:
+  - Lars Poeschel <poeschel@lemonage.de>
+
+description:
+  The LCD2S is a Character LCD Display manufactured by Modtronix Engineering.
+  The display supports a serial I2C and SPI interface. The driver currently
+  only supports the I2C interface.
+
+properties:
+  compatible:
+    const: modtronix,lcd2s
+
+  reg:
+    maxItems: 1
+    description:
+      I2C bus address of the display.
+
+  display-height-chars:
+    description: Height of the display, in character cells.
+    $ref: /schemas/types.yaml#/definitions/uint32
+    minimum: 1
+    maximum: 4
+
+  display-width-chars:
+    description: Width of the display, in character cells.
+    $ref: /schemas/types.yaml#/definitions/uint32
+    minimum: 16
+    maximum: 20
+
+required:
+  - compatible
+  - reg
+  - display-height-chars
+  - display-width-chars
+
+additionalProperties: false
+
+examples:
+  - |
+    i2c {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      lcd2s: auxdisplay@28 {
+        compatible = "modtronix,lcd2s";
+        reg = <0x28>;
+        display-height-chars = <4>;
+        display-width-chars = <20>;
+      };
+    };

Documentation/devicetree/bindings/vendor-prefixes.yaml

@@ -683,6 +683,8 @@ patternProperties:
     description: MiraMEMS Sensing Technology Co., Ltd.
   "^mitsubishi,.*":
     description: Mitsubishi Electric Corporation
+  "^modtronix,.*":
+    description: Modtronix Engineering
   "^mosaixtech,.*":
     description: Mosaix Technologies, Inc.
   "^motorola,.*":

drivers/auxdisplay/Kconfig

@@ -16,10 +16,29 @@ menuconfig AUXDISPLAY
 
 if AUXDISPLAY
 
+config CHARLCD
+	tristate "Character LCD core support" if COMPILE_TEST
+	help
+	  This is the base system for character-based LCD displays.
+	  It makes no sense to have this alone, you select your display driver
+	  and if it needs the charlcd core, it will select it automatically.
+	  This is some character LCD core interface that multiple drivers can
+	  use.
+
+config HD44780_COMMON
+	tristate "Common functions for HD44780 (and compatibles) LCD displays" if COMPILE_TEST
+	select CHARLCD
+	help
+	  This is a module with the common symbols for HD44780 (and compatibles)
+	  displays. This is the code that multiple other modules use. It is not
+	  useful alone. If you have some sort of HD44780 compatible display,
+	  you very likely use this. It is selected automatically by selecting
+	  your concrete display.
+
 config HD44780
 	tristate "HD44780 Character LCD support"
 	depends on GPIOLIB || COMPILE_TEST
-	select CHARLCD
+	select HD44780_COMMON
 	help
 	  Enable support for Character LCDs using a HD44780 controller.
 	  The LCD is accessible through the /dev/lcd char device (10, 156).
@@ -154,6 +173,16 @@ config HT16K33
 	  Say yes here to add support for Holtek HT16K33, RAM mapping 16*8
 	  LED controller driver with keyscan.
 
+config LCD2S
+	tristate "lcd2s 20x4 character display over I2C console"
+	depends on I2C
+	select CHARLCD
+	help
+	  This is a driver that lets you use the lcd2s 20x4 character display
+	  from Modtronix engineering as a console output device. The display
+	  is a simple single color character display. You have to connect it
+	  to an I2C bus.
+
 config ARM_CHARLCD
 	bool "ARM Ltd. Character LCD Driver"
 	depends on PLAT_VERSATILE
@@ -167,7 +196,7 @@ config ARM_CHARLCD
 menuconfig PARPORT_PANEL
 	tristate "Parallel port LCD/Keypad Panel support"
 	depends on PARPORT
-	select CHARLCD
+	select HD44780_COMMON
 	help
 	  Say Y here if you have an HD44780 or KS-0074 LCD connected to your
 	  parallel port. This driver also features 4 and 6-key keypads. The LCD

drivers/auxdisplay/Makefile

@@ -4,10 +4,12 @@
 #
 
 obj-$(CONFIG_CHARLCD)		+= charlcd.o
+obj-$(CONFIG_HD44780_COMMON)	+= hd44780_common.o
 obj-$(CONFIG_ARM_CHARLCD)	+= arm-charlcd.o
 obj-$(CONFIG_KS0108)		+= ks0108.o
 obj-$(CONFIG_CFAG12864B)	+= cfag12864b.o cfag12864bfb.o
 obj-$(CONFIG_IMG_ASCII_LCD)	+= img-ascii-lcd.o
 obj-$(CONFIG_HD44780)		+= hd44780.o
 obj-$(CONFIG_HT16K33)		+= ht16k33.o
 obj-$(CONFIG_PARPORT_PANEL)	+= panel.o
+obj-$(CONFIG_LCD2S)		+= lcd2s.o