Added 1.8" LCD Adafruit on SPI0

3 files changed, 210 insertions, 7 deletions

diff --git a/src/arm/BB-LCD-ADAFRUIT-18-SPI0-00A0.dts b/src/arm/BB-LCD-ADAFRUIT-18-SPI0-00A0.dts
new file mode 100644
index 0000000..2b958ba
--- /dev/null
+++ b/src/arm/BB-LCD-ADAFRUIT-18-SPI0-00A0.dts
@@ -0,0 +1,203 @@
+/*
+ * Copyright (C) 2013 CircuitCo
+ * Copyright (C) 2018 Drew Fustini <drew@beagleboard.org>
+ * Copyright (C) 2020 Mark A. Yoder <mark.a.yoder@beagleboard.org>
+ *
+ * Adafruit 21.8 TFT LCD on SPI0 bus using tinydrm ili9341 driver
+ *
+ * LICENSE:
+ * --------
+ * 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.
+ *
+ * DOCUMENTATION:
+ * --------------
+ * This file was copied from src/arm/BB-SPIDEV1-00A0.dts and modified
+ * by Drew Fustini based on an exmample from David Lechner.
+ * Later modified by Mark A. Yoder for the 2.4" LCD.
+ *
+ * This is the Adafruit 1.8" TFT LCD:
+ * https://www.adafruit.com/product/358
+ *
+ * It should be connected to BeagleBone SPI0 bus:
+ *
+ *   P9.16 <--> lite (pwm) [OPTIONAL]
+ *   P9.17 <--> tft_cs
+ *   P9.18 <--> mosi
+ *   P9.19 <--> dc
+ *   P9.20 <--> reset
+ *   P9.22 <--> clk
+ *   P9.23 <--> lite (gpio) [OPTIONAL]
+ *
+ * This overlay will load the mainline tinydrm ili9341 driver by David Lechner:
+ * https://github.com/torvalds/linux/blob/master/drivers/gpu/drm/tiny/ili9341.c
+ *
+ * Tested with 4.19.59-ti-r26 kernel on Debian 10.1 image
+ *
+ * Mailing list post with more information:
+ * https://groups.google.com/d/msg/beagleboard/GuMQIP_XCW0/b3lxbx_8AwAJ
+ *
+ * Discussion with notro on how to test tinydrm driver:
+ * https://github.com/notro/tinydrm/issues/1#issuecomment-367279037
+ */
+
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/pinctrl/am33xx.h>
+#include <dt-bindings/board/am335x-bbw-bbb-base.h>
+
+/dts-v1/;
+/plugin/;
+
+/ {
+	/*
+	 * Helper to show loaded overlays under: /proc/device-tree/chosen/overlays/
+	 */
+	fragment@0 {
+		target-path="/";
+		__overlay__ {
+
+			chosen {
+				overlays {
+					BB-LCD-ADAFRUIT-18-SPI0-00A0 = __TIMESTAMP__;
+				};
+			};
+		};
+	};
+
+	/*
+	 * Free up the pins used by the cape from the pinmux helpers.
+	 */
+
+	fragment@1 {
+		target = <&ocp>;
+		__overlay__ {
+			P9_16_pinmux { status = "disabled"; };  /* lcd pwm backlight (OPTIONAL) */
+			P9_19_pinmux { status = "disabled"; };	/* lcd dc */
+			P9_20_pinmux { status = "disabled"; };	/* lcd reset */
+		//	P9_23_pinmux { status = "disabled"; };	/* lcd gpio backlight (OPTIONAL) */
+			P9_17_pinmux { status = "disabled"; };	/* spi0_cs0 */
+			P9_21_pinmux { status = "disabled"; };	/* spi0_d0 */
+			P9_18_pinmux { status = "disabled"; };	/* spi0_d1 */
+			P9_22_pinmux { status = "disabled"; };	/* spi0_sclk */
+		};
+	};
+
+	fragment@2 {
+		target = <&am33xx_pinmux>;
+		__overlay__ {
+			/* default state has all gpios released and mode set to uart1 */
+			/* See page 1446 of am35xx TRM */
+			bb_spi0_pins: pinmux_bb_spi0_pins {
+				pinctrl-single,pins = <
+					BONE_P9_22 0x30	/* mcasp0_aclkx.spi0_sclk,  INPUT_PULLUP | MODE0 */
+					BONE_P9_21 0x30	/* mcasp0_fsx.spi0_d0,      INPUT_PULLUP | MODE0 */
+					BONE_P9_18 0x10	/* mcasp0_axr0.spi0_d1,    OUTPUT_PULLUP | MODE0 */
+					BONE_P9_17 0x10	/* mcasp0_ahclkr.spi0_cs0, OUTPUT_PULLUP | MODE0 */
+					BONE_P9_19 0x17	/* gpio, dc,    		   OUTPUT_PULLUP | MODE07*/
+					BONE_P9_20 0x17	/* gpio, reset, 		   OUTPUT_PULLUP | MODE07*/
+					// No cs1 for spi0
+				>;
+			};
+
+			backlight_pwm_pins: pinmux_backlight_pwm_pins {
+				pinctrl-single,pins = <
+					BONE_P9_16 0x06 /* gpmc_a2.ehrpwm1b, OMAP_MUX_MODE6 | AM33XX_PIN_OUTPUT */
+				>;
+			};  /* gpmc_a2.ehrpwm1b */
+		};
+	};
+
+	fragment@3 {
+		target = <&epwmss1>;
+		__overlay__ {
+			status = "okay";
+		};
+	};
+
+	fragment@4 {
+		target = <&ehrpwm1>;
+		__overlay__ {
+			pinctrl-names = "default";
+			pinctrl-0 = <&backlight_pwm_pins>;
+			status = "okay";
+		};
+	};
+
+	fragment@5 {
+		target-path = "/";
+		__overlay__ {
+
+			bl_reg: backlight-regulator {
+				compatible = "regulator-fixed";
+				regulator-name = "backlight";
+				regulator-always-on;
+				regulator-boot-on;
+			};
+
+			/* backlight is optional */
+			backlight_gpio: backlight_gpio {
+				compatible = "gpio-backlight";
+				gpios = <&gpio1 17 GPIO_ACTIVE_HIGH>;
+				// connect lcd lite pin to P9.23 which is gpio1[17]
+				// refer to https://elinux.org/Beagleboard:Cape_Expansion_Headers
+			};
+
+			/*
+			 * Turn the PWM backlight on by setting bl_power to 0:
+			 * echo 0 > /sys/class/backlight/backlight_pwm/bl_power
+			 */
+			backlight_pwm: backlight_pwm {
+				// P9.16 <--> lite (pwm-backlight EHRPWM1A)
+				status = "okay";
+				compatible = "pwm-backlight";
+				pwms = <&ehrpwm1 1 500000 0>;	// First digit: 0 for A side of pwm, 1 for B side
+												// 500000 is the PWM period in ns
+												// https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/devicetree/bindings/pwm/pwm.txt
+				brightness-levels = <
+					0  1  2  3  4  5  6  7  8  9
+					10 11 12 13 14 15 16 17 18 19
+					20 21 22 23 24 25 26 27 28 29
+					30 31 32 33 34 35 36 37 38 39
+					40 41 42 43 44 45 46 47 48 49
+					50 51 52 53 54 55 56 57 58 59
+					60 61 62 63 64 65 66 67 68 69
+					70 71 72 73 74 75 76 77 78 79
+					80 81 82 83 84 85 86 87 88 89
+					90 91 92 93 94 95 96 97 98 99
+					100
+				>;
+				default-brightness-level = <100>;
+				power-supply = <&bl_reg>;
+			};
+		};
+	};
+
+	fragment@6 {
+		target = <&spi0>;
+		__overlay__ {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			status = "okay";
+			pinctrl-names = "default";
+			pinctrl-0 = <&bb_spi0_pins>;
+
+			display@0{
+				status = "okay";
+				compatible = "jianda,jd-t18003-t01", "sitronix,st7735r";
+				reg = <0>;
+				spi-max-frequency = <16000000>;
+				dc-gpios    = <&gpio0 13 0>;   // lcd dc    P9.19 gpio0[13]
+				reset-gpios = <&gpio0 12 0>;   // lcd reset P9.20 gpio0[12]
+				// backlight is optional
+				// choose either pwm or gpio control
+				//backlight = <&backlight_gpio>; // lcd lite  P9.23 gpio1[17]
+				backlight = <&backlight_pwm>;    // lcd lite  P9.16 gpmc_a2.ehrpwm1b
+				// refer to https://elinux.org/Beagleboard:Cape_Expansion_Headers
+				// rotation is optional
+				rotation = <90>;
+			};
+		};
+	};
+};
diff --git a/src/arm/BB-LCD-ADAFRUIT-24-SPI0-00A0.dts b/src/arm/BB-LCD-ADAFRUIT-24-SPI0-00A0.dts
index cbbaf5b..568ff32 100644
--- a/src/arm/BB-LCD-ADAFRUIT-24-SPI0-00A0.dts
+++ b/src/arm/BB-LCD-ADAFRUIT-24-SPI0-00A0.dts
@@ -22,14 +22,14 @@
  *
  * It should be connected to BeagleBone SPI0 bus:
  *
- *   P9.20 <--> reset
  *   P9.16 <--> lite (pwm) [OPTIONAL]
- *   P9.19 <--> dc
- *   P9.23 <--> lite (gpio) [OPTIONAL]
  *   P9.17 <--> tft_cs
  *   P9.18 <--> mosi
+ *   P9.19 <--> dc
+ *   P9.20 <--> reset
  *   P9.21 <--> miso
  *   P9.22 <--> clk
+ *   P9.23 <--> lite (gpio) [OPTIONAL]
  *
  * This overlay will load the mainline tinydrm ili9341 driver by David Lechner:
  * https://github.com/torvalds/linux/blob/master/drivers/gpu/drm/tiny/ili9341.c
@@ -80,10 +80,10 @@
 	fragment@1 {
 		target = <&ocp>;
 		__overlay__ {
-			P9_20_pinmux { status = "disabled"; };	/* lcd reset */
 			P9_16_pinmux { status = "disabled"; };  /* lcd pwm backlight (OPTIONAL) */
 			P9_19_pinmux { status = "disabled"; };	/* lcd dc */
-		/*	P9_23_pinmux { status = "disabled"; };	/* lcd gpio backlight (OPTIONAL) */
+			P9_20_pinmux { status = "disabled"; };	/* lcd reset */
+		//	P9_23_pinmux { status = "disabled"; };	/* lcd gpio backlight (OPTIONAL) */
 			P9_17_pinmux { status = "disabled"; };	/* spi0_cs0 */
 			P9_21_pinmux { status = "disabled"; };	/* spi0_d0 */
 			P9_18_pinmux { status = "disabled"; };	/* spi0_d1 */
diff --git a/src/arm/BB-LCD-ADAFRUIT-24-SPI1-00A0.dts b/src/arm/BB-LCD-ADAFRUIT-24-SPI1-00A0.dts
index 05be7b7..3451ddd 100644
--- a/src/arm/BB-LCD-ADAFRUIT-24-SPI1-00A0.dts
+++ b/src/arm/BB-LCD-ADAFRUIT-24-SPI1-00A0.dts
@@ -22,10 +22,10 @@
  *
  * It should be connected to BeagleBone SPI1 bus:
  *
- *   P9.25 <--> reset
  *   P9.16 <--> lite (pwm) [OPTIONAL]
- *   P9.27 <--> dc
  *   P9.23 <--> lite (gpio) [OPTIONAL]
+ *   P9.25 <--> reset
+ *   P9.27 <--> dc
  *   P9.28 <--> tft_cs
  *   P9.29 <--> miso
  *   P9.30 <--> mosi