display: tearing effect cleanup

Makefile

@@ -21,10 +21,6 @@ CFLAGS += -DDISPLAY_ILI9341V=1
 CFLAGS += -DDISPLAY_ST7789V=0
 endif
 
-ifeq ($(DISPLAY_VSYNC), 0)
-CFLAGS += -DDISPLAY_VSYNC=0
-endif
-
 PRODUCTION ?= 0
 
 STLINK_VER ?= v2

docs/hardware.md

@@ -24,7 +24,7 @@ TODO
 * 1 x USB Cable Type A Plug/Male to Type Micro-B Plug/Male
 * 1 x [ER-TFTM028-4 Display + Capacitive Touch Panel Module](http://www.ebay.com/itm/302049581340) (Note: specify 40-Pin Header, 8080 8-bit Parallel, VDD=3.3V, Capacitive Touch Panel)
 * 1 x [microSD Board](https://www.waveshare.com/product/modules/storage/sd-tf-storage/micro-sd-storage-board.htm)
-* 27 x Female to female jumper wires with 0.1" header contacts
+* 28 x Female to female jumper wires with 0.1" header contacts
 
 #### Display
 
@@ -38,7 +38,7 @@ TODO
 |Description|MCU Pin|Notes|
 |-----------|-------|-----|
 |LCD_RST|PC14|display module pin 21|
-|LCD_FMARK|PD12|tearing effect input|
+|LCD_FMARK|PD12|tearing effect input; display module pin 22|
 |LCD_PWM|PA7|backlight control (brightness); display module pin 29|
 |LCD_CS|PD7|display module pin 23|
 |LCD_RS|PD11|register select aka command/data; display module pin 24|

embed/extmod/modtrezorui/display-stm32.h

@@ -15,10 +15,6 @@
 #define DISPLAY_ST7789V  1
 #endif
 
-#ifndef DISPLAY_VSYNC
-#define DISPLAY_VSYNC    1
-#endif
-
 // FSMC/FMC Bank 1 - NOR/PSRAM 1
 #define DISPLAY_MEMORY_BASE  0x60000000
 #define DISPLAY_MEMORY_PIN   16
@@ -172,10 +168,11 @@ int display_init(void) {
     HAL_GPIO_WritePin(GPIOC, GPIO_PIN_14, GPIO_PIN_SET);
 
     // LCD_FMARK/PD12 (tearing effect)
-    GPIO_InitStructure.Pin = GPIO_PIN_12;
     GPIO_InitStructure.Mode = GPIO_MODE_INPUT;
     GPIO_InitStructure.Pull = GPIO_NOPULL;
     GPIO_InitStructure.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
+    GPIO_InitStructure.Alternate = 0;
+    GPIO_InitStructure.Pin = GPIO_PIN_12;
     HAL_GPIO_Init(GPIOD, &GPIO_InitStructure);
 
     GPIO_InitStructure.Mode      = GPIO_MODE_AF_PP;
@@ -242,6 +239,7 @@ int display_init(void) {
     CMD(0xC1); DATA(0x12);                          // power control   SAP[2:0] BT[3:0]
     CMD(0xC5); DATA(0x60); DATA(0x44);              // vcm control 1
     CMD(0xC7); DATA(0x8A);                          // vcm control 2
+    CMD(0x35); DATA(0x00);                          // TEON: Tearing Effect Line On
     CMD(0x3A); DATA(0x55);                          // memory access control (16-bit 565)
     CMD(0xB1); DATA(0x00); DATA(0x18);              // framerate
     CMD(0xB6); DATA(0x0A); DATA(0xA2);              // display function control
@@ -299,12 +297,11 @@ static void display_set_window(uint16_t x0, uint16_t y0, uint16_t x1, uint16_t y
     display_set_window_raw(x0, y0, x1, y1);
 }
 
-void display_refresh(void) {
-#if DISPLAY_VSYNC
+void display_refresh(void)
+{
     // synchronize with the panel synchronization signal in order to avoid visual tearing effects
     while (GPIO_PIN_RESET == HAL_GPIO_ReadPin(GPIOD, GPIO_PIN_12)) { }
     while (GPIO_PIN_SET == HAL_GPIO_ReadPin(GPIOD, GPIO_PIN_12)) { }
-#endif
 }
 
 void display_save(const char *filename)