ugfx/drivers/gdisp/Nokia6610GE8/gdisp_lld_Nokia6610GE8.c

/*
 * This file is subject to the terms of the GFX License. If a copy of
 * the license was not distributed with this file, you can obtain one at:
 *
 *              http://ugfx.org/license.html
 */

/**
 * @file    drivers/gdisp/Nokia6610GE8/gdisp_lld.c
 * @brief   GDISP Graphics Driver subsystem low level driver source for the Nokia6610 GE8 display.
 *
 * @addtogroup GDISP
 * @{
 */

#include "gfx.h"

#if GFX_USE_GDISP

/**
 * This is for the EPSON (GE8) controller driving a Nokia6610 color LCD display.
 * Note that there is also a PHILIPS (GE12) controller for the same display that this code
 * does not support.
 *
 * The controller drives a 132x132 display but a 1 pixel surround is not visible
 * which gives a visible area of 130x130.
 *
 * This controller does not support reading back over the SPI interface.
 * Additionally, the Olimex board doesn't even connect the pin.
 *
 * The hardware is capable of doing full width vertical scrolls aligned
 * on a 4 line boundary however that is not sufficient to support general vertical scrolling.
 * We also can't manually do read/modify scrolling because we can't read in SPI mode.
 *
 * The controller has some quirkyness when operating in other than rotation 0 mode.
 * When any direction is decremented it starts at location 0 rather than the end of
 * the area. Whilst this can be handled when we know the specific operation (pixel, fill, blit)
 * it cannot be handled in a generic stream operation. So, when orientation support is turned
 * on (and needed) we use complex operation specific routines instead of simple streaming
 * routines. This has a (small) performance penalty and a significant code size penalty so
 * don't turn on orientation support unless you really need it.
 *
 * Some of the more modern controllers have a broken command set. If you have one of these
 * you will recognise it by the colors being off on anything drawn after an odd (as opposed to
 * even) pixel count area being drawn. If so then set GDISP_GE8_BROKEN_CONTROLLER to TRUE
 * on your gdisp_lld_board.h file. The price is that streaming calls that are completed
 * without exactly the window size write operations and where the number of write operations
 * is odd (rather than even), it will draw an extra pixel. If this is important to you, turn on
 * orientation support and the streaming operations will be emulated (as described above).
 */

#if defined(GDISP_SCREEN_HEIGHT)
	#warning "GDISP: This low level driver does not support setting a screen size. It is being ignored."
	#undef GDISP_SCREEN_HEIGHT
#endif
#if defined(GDISP_SCREEN_WIDTH)
	#warning "GDISP: This low level driver does not support setting a screen size. It is being ignored."
	#undef GDISP_SCREEN_WIDTH
#endif

#define GDISP_DRIVER_VMT			GDISPVMT_Nokia6610GE8
#include "drivers/gdisp/Nokia6610GE8/gdisp_lld_config.h"
#include "src/gdisp/driver.h"

#include "board_Nokia6610GE8.h"

/*===========================================================================*/
/* Driver local definitions.                                                 */
/*===========================================================================*/

#include "drivers/gdisp/Nokia6610GE8/GE8.h"

#define GDISP_SCAN_LINES			132

// Set parameters if they are not already set
#ifndef GDISP_GE8_BROKEN_CONTROLLER
	#define GDISP_GE8_BROKEN_CONTROLLER		TRUE
#endif
#ifndef GDISP_SCREEN_HEIGHT
	#define GDISP_SCREEN_HEIGHT		130
#endif
#ifndef GDISP_SCREEN_WIDTH
	#define GDISP_SCREEN_WIDTH		130
#endif
#ifndef GDISP_RAM_X_OFFSET
	#define GDISP_RAM_X_OFFSET		0		/* Offset in RAM of visible area */
#endif
#ifndef GDISP_RAM_Y_OFFSET
	#define GDISP_RAM_Y_OFFSET		2		/* Offset in RAM of visible area */
#endif
#ifndef GDISP_SLEEP_SIZE
	#define GDISP_SLEEP_SIZE		32		/* Sleep mode window lines */
#endif
#ifndef GDISP_SLEEP_POS
	#define GDISP_SLEEP_POS			((GDISP_SCAN_LINES-GDISP_SLEEP_SIZE)/2)
#endif
#ifndef GDISP_INITIAL_CONTRAST
	#define GDISP_INITIAL_CONTRAST	60
#endif
#ifndef GDISP_INITIAL_BACKLIGHT
	#define GDISP_INITIAL_BACKLIGHT	100
#endif

/*===========================================================================*/
/* Driver exported variables.                                                */
/*===========================================================================*/

/*===========================================================================*/
/* Driver local variables.                                                   */
/*===========================================================================*/

#if GDISP_HARDWARE_STREAM_WRITE
	typedef struct dvrPriv {
		uint16_t			savecolor;
		#if GDISP_GE8_BROKEN_CONTROLLER
			uint16_t		firstcolor;
		#endif
	} dvrPriv;
	#define PRIV		((dvrPriv *)g->priv)
#endif

#define GDISP_FLG_ODDBYTE	(GDISP_FLG_DRIVER<<0)
#define GDISP_FLG_RUNBYTE	(GDISP_FLG_DRIVER<<1)

/*===========================================================================*/
/* Driver local functions.                                                   */
/*===========================================================================*/

// Some macros just to make reading the code easier
#define delayms(ms)							gfxSleepMilliseconds(ms)
#define write_data2(g, d1, d2)				{ write_data(g, d1); write_data(g, d2); }
#define write_data3(g, d1, d2, d3)			{ write_data(g, d1); write_data(g, d2); write_data(g, d3); }
#define write_data4(g, d1, d2, d3, d4)		{ write_data(g, d1); write_data(g, d2); write_data(g, d3); write_data(g, d4); }
#define write_cmd1(g, cmd, d1)				{ write_index(g, cmd); write_data(g, d1); }
#define write_cmd2(g, cmd, d1, d2)			{ write_index(g, cmd); write_data2(g, d1, d2); }
#define write_cmd3(g, cmd, d1, d2, d3)		{ write_index(g, cmd); write_data3(g, d1, d2, d3); }
#define write_cmd4(g, cmd, d1, d2, d3, d4)	{ write_index(g, cmd); write_data4(g, d1, d2, d3, d4); }

static inline void set_viewport(GDisplay* g) {
	#if GDISP_NOKIA_ORIENTATION && GDISP_NEED_CONTROL
		switch(g->g.Orientation) {
		default:
		case GDISP_ROTATE_0:
			write_cmd2(g, CASET, GDISP_RAM_X_OFFSET+g->p.x, GDISP_RAM_X_OFFSET+g->p.x);			// Column address set
			write_cmd2(g, PASET, GDISP_RAM_Y_OFFSET+g->p.y, GDISP_RAM_Y_OFFSET+g->p.y);			// Page address set
			break;
		case GDISP_ROTATE_90:
			write_cmd2(g, CASET, GDISP_RAM_X_OFFSET+g->p.y, GDISP_RAM_X_OFFSET+g->p.y);
			write_cmd2(g, PASET, GDISP_RAM_Y_OFFSET-1+g->g.Width-g->p.x, GDISP_RAM_Y_OFFSET-1+g->g.Width-g->p.x);
			break;
		case GDISP_ROTATE_180:
			write_cmd2(g, CASET, GDISP_RAM_X_OFFSET-1+g->g.Width-g->p.x, GDISP_RAM_X_OFFSET-1+g->g.Width-g->p.x);
			write_cmd2(g, PASET, GDISP_RAM_Y_OFFSET-1+g->g.Height-g->p.y, GDISP_RAM_Y_OFFSET-1+g->g.Height-g->p.y);
			break;
		case GDISP_ROTATE_270:
			write_cmd2(g, CASET, GDISP_RAM_X_OFFSET-1+g->g.Height-g->p.y, GDISP_RAM_X_OFFSET-1+g->g.Height-g->p.y);
			write_cmd2(g, PASET, GDISP_RAM_Y_OFFSET+g->p.x, GDISP_RAM_Y_OFFSET+g->p.x);
			break;
		}
	#else
		write_cmd2(g, CASET, GDISP_RAM_X_OFFSET+g->p.x, GDISP_RAM_X_OFFSET+g->p.x+g->p.cx-1);			// Column address set
		write_cmd2(g, PASET, GDISP_RAM_Y_OFFSET+g->p.y, GDISP_RAM_Y_OFFSET+g->p.y+g->p.cy-1);			// Page address set
	#endif
	write_index(g, RAMWR);
}
/*===========================================================================*/
/* Driver exported functions.                                                */
/*===========================================================================*/

LLDSPEC bool_t gdisp_lld_init(GDisplay *g) {
	#if GDISP_HARDWARE_STREAM_WRITE
		g->priv = gfxAlloc(sizeof(dvrPriv));
	#else
		g->priv = 0;
	#endif

	// Initialise the board interface
	init_board(g);

	// Hardware reset
	setpin_reset(g, TRUE);
	delayms(20);
	setpin_reset(g, FALSE);
	delayms(20);

	// Get the bus for the following initialisation commands
	acquire_bus(g);
	
	write_cmd4(g, DISCTL, 0x00, GDISP_SCAN_LINES/4-1, 0x0A, 0x00);	// Display control - How the controller drives the LCD
															// P1: 0x00 = 2 divisions, switching period=8 (default)
															// P2: 0x20 = nlines/4 - 1 = 132/4 - 1 = 32)
															// P3: 0x0A = standard inverse highlight, inversion every frame
															// P4: 0x00 = dispersion on
	write_cmd1(g, COMSCN, 0x01);							// COM scan - How the LCD is connected to the controller
															// P1: 0x01 = Scan 1->80, 160<-81
	write_index(g, OSCON);									// Internal oscillator ON
	write_index(g, SLPOUT);									// Sleep out
	write_cmd1(g, PWRCTR, 0x0F);							// Power control - reference voltage regulator on, circuit voltage follower on, BOOST ON
	write_cmd3(g, DATCTL, 0x00, 0x00, 0x02);				// Data control
															// P1: 0x00 = page address normal, column address normal, address scan in column direction
															// P2: 0x00 = RGB sequence (default value)
															// P3: 0x02 = 4 bits per colour (Type A)
	write_cmd2(g, VOLCTR, 64*GDISP_INITIAL_CONTRAST/101, 0x03);	// Voltage control (contrast setting)
															// P1 = Contrast (0..63)
															// P2 = 3 resistance ratio (only value that works)
	delayms(100);										// Allow power supply to stabilise
	write_index(g, DISON);									// Turn on the display

    // Finish Init
    post_init_board(g);

	// Release the bus
	release_bus(g);
	
	/* Turn on the back-light */
	set_backlight(g, GDISP_INITIAL_BACKLIGHT);

	/* Initialise the GDISP structure to match */
	g->g.Orientation = GDISP_ROTATE_0;
	g->g.Powermode = powerOn;
	g->g.Backlight = GDISP_INITIAL_BACKLIGHT;
	g->g.Contrast = GDISP_INITIAL_CONTRAST;
	g->g.Width = GDISP_SCREEN_WIDTH;
	g->g.Height = GDISP_SCREEN_HEIGHT;
	return TRUE;
}

#if GDISP_HARDWARE_STREAM_WRITE
	LLDSPEC	void gdisp_lld_write_start(GDisplay *g) {
		acquire_bus(g);
		set_viewport(g);
		g->flags &= ~(GDISP_FLG_ODDBYTE|GDISP_FLG_RUNBYTE);
	}
	LLDSPEC	void gdisp_lld_write_color(GDisplay *g) {
		uint16_t	c;

		c = gdispColor2Native(g->p.color);
		#if GDISP_GE8_BROKEN_CONTROLLER
			if (!(g->flags & GDISP_FLG_RUNBYTE)) {
				PRIV->firstcolor = c;
				g->flags |= GDISP_FLG_RUNBYTE;
			}
		#endif
		if ((g->flags & GDISP_FLG_ODDBYTE)) {
			// Write the pair of pixels to the display
			write_data3(g, ((PRIV->savecolor >> 4) & 0xFF),
					(((PRIV->savecolor << 4) & 0xF0)|((c >> 8) & 0x0F)),
					(c & 0xFF));
			g->flags &= ~GDISP_FLG_ODDBYTE;
		} else {
			PRIV->savecolor = c;
			g->flags |= GDISP_FLG_ODDBYTE;
		}
	}
	LLDSPEC	void gdisp_lld_write_stop(GDisplay *g) {
		if ((g->flags & GDISP_FLG_ODDBYTE)) {
			#if GDISP_GE8_BROKEN_CONTROLLER
				/**
				 * We have a real problem here - we need to write a singular pixel
				 * Methods that are supposed to work...
				 * 1/ Write the pixel (2 bytes) and then send a NOP command. This doesn't work, the pixel doesn't get written
				 * 		and it is maintained in the latch where it causes problems for the next window.
				 * 2/ Just write a dummy extra pixel as stuff beyond the window gets discarded. This doesn't work as contrary to
				 * 		the documentation the buffer wraps and the first pixel gets overwritten.
				 * 3/ Put the controller in 16 bits per pixel Type B mode where each pixel is performed by writing two bytes. This
				 * 		also doesn't work as the controller refuses to enter Type B mode (it stays in Type A mode).
				 *
				 * These methods might work on some controllers - just not on the one of the broken versions.
				 *
				 * For these broken controllers:
				 * 	We know we can wrap to the first byte (just overprint it) if we are at the end of the stream area.
				 * 	If not, we need to create a one pixel by one pixel window to fix this - Uuch. Fortunately this should only happen if the
				 * 	user application uses the streaming calls and then terminates the stream early or after buffer wrap.
				 * 	Since this is such an unlikely situation we just don't handle it.
				 */
				write_data3(g, ((PRIV->savecolor >> 4) & 0xFF),
						(((PRIV->savecolor << 4) & 0xF0)|((PRIV->firstcolor >> 8) & 0x0F)),
						(PRIV->firstcolor & 0xFF));
			#else
				write_data2(g, ((PRIV->savecolor >> 4) & 0xFF), ((PRIV->savecolor << 4) & 0xF0));
				write_index(g, NOP);
			#endif
		}

		release_bus(g);
	}
#endif

#if GDISP_HARDWARE_DRAWPIXEL
	LLDSPEC void gdisp_lld_draw_pixel(GDisplay *g) {
		uint16_t	c;

		c = gdispColor2Native(g->p.color);
		acquire_bus(g);
		set_viewport(g);
		write_data3(g, 0, (c>>8) & 0x0F, c & 0xFF);
		release_bus(g);
	}
#endif

/* ---- Optional Routines ---- */

#if GDISP_HARDWARE_FILLS
	LLDSPEC void gdisp_lld_fill_area(GDisplay *g) {
		unsigned	tuples;
		uint16_t	c;

		tuples = (g->p.cx*g->p.cy+1)>>1;	// With an odd sized area we over-print by one pixel.
											// This extra pixel overwrites the first pixel (harmless as it is the same colour)

		c = gdispColor2Native(g->p.color);
		acquire_bus(g);
		set_viewport(g);
		while(tuples--)
			write_data3(g, ((c >> 4) & 0xFF), (((c << 4) & 0xF0)|((c >> 8) & 0x0F)), (c & 0xFF));
		release_bus(g);
	}
#endif

#if GDISP_HARDWARE_BITFILLS
	LLDSPEC void gdisp_lld_blit_area(GDisplay *g) {
		coord_t			lg, x, y;
		uint16_t		c1, c2;
		unsigned		tuples;
		const pixel_t	*buffer;
		#if GDISP_PACKED_PIXELS
			unsigned		pnum, pstart;
			const uint8_t	*p;
		#else
			const pixel_t	*p;
		#endif

		tuples = (g->p.cx * g->p.cy + 1)>>1;
		buffer = (const pixel_t *)g->p.ptr;

		/* Set up the data window to transfer */
		acquire_bus(g);
		set_viewport(g);

		/* to suppress compiler warnings */
		x = 0;
		y = 0;

		/*
		 * Due to the way the Nokia6610 handles a decrementing column or page,
		 * we have to make adjustments as to where it is actually drawing from in the bitmap.
		 * For example, for 90 degree rotation the column is decremented on each
		 * memory write. The controller always starts with column 0 and then decrements
		 * to column cx-1, cx-2 etc. We therefore have to write-out the last bitmap line first.
		 */
		switch(g->g.Orientation) {
		default:
		case GDISP_ROTATE_0:		x = 0;			y = 0;			break;
		case GDISP_ROTATE_90:		x = g->p.cx-1;	y = 0;			break;
		case GDISP_ROTATE_180:		x = g->p.cx-1;	y = g->p.cy-1;	break;
		case GDISP_ROTATE_270:		x = 0;			y = g->p.cy-1;	break;
		}

		#if !GDISP_PACKED_PIXELS
			// Although this controller uses packed pixels we support unpacked pixel
			//  formats in this blit by packing the data as we feed it to the controller.

			lg = g->p.x2 - g->p.cx;					// The buffer gap between lines
			buffer += g->p.y1 * g->p.x2 + g->p.x1;	// The buffer start position
			p = buffer + g->p.x2*y + x;				// Adjustment for controller craziness

			while(tuples--) {
				/* Get a pixel */
				c1 = gdispColor2Native(*p++);

				/* Check for line or buffer wrapping */
				if (++x >= g->p.cx) {
					x = 0;
					p += lg;
					if (++y >= g->p.cy) {
						y = 0;
						p = buffer;
					}
				}

				/* Get the next pixel */
				c2 = gdispColor2Native(*p++);

				/* Check for line or buffer wrapping */
				if (++x >= g->p.cx) {
					x = 0;
					p += lg;
					if (++y >= g->p.cy) {
						y = 0;
						p = buffer;
					}
				}

				/* Write the pair of pixels to the display */
				write_data3(g, ((c1 >> 4) & 0xFF), (((c1 << 4) & 0xF0)|((c2 >> 8) & 0x0F)), (c2 & 0xFF));
			}

		#elif GDISP_PIXELFORMAT == GDISP_LLD_PIXELFORMAT

			// Although this controller uses packed pixels, we may have to feed it into
			//  the controller with different packing to the source bitmap
			// There are 2 pixels per 3 bytes

			#if !GDISP_PACKED_LINES
				srccx = (g->p.x2 + 1) & ~1;
			#endif
			pstart = g->p.y1 * g->p.x2 + g->p.x1;										// The starting pixel number
			buffer = (const pixel_t)(((const uint8_t *)buffer) + ((pstart>>1) * 3));	// The buffer start position
			lg = ((g->p.x2-g->p.cx)>>1)*3;												// The buffer gap between lines
			pnum = pstart + g->p.x2*y + x;												// Adjustment for controller craziness
			p = ((const uint8_t *)buffer) + (((g->p.x2*y + x)>>1)*3);					// Adjustment for controller craziness

			while (tuples--) {
				/* Get a pixel */
				switch(pnum++ & 1) {
				case 0:		c1 = (((color_t)p[0]) << 4)|(((color_t)p[1])>>4);				break;
				case 1:		c1 = (((color_t)p[1]&0x0F) << 8)|((color_t)p[1]);	p += 3;		break;
				}

				/* Check for line or buffer wrapping */
				if (++x >= g->p.cx) {
					x = 0;
					p += lg;
					pnum += g->p.x2 - g->p.cx;
					if (++y >= g->p.cy) {
						y = 0;
						p = (const uint8_t *)buffer;
						pnum = pstart;
					}
				}

				/* Get the next pixel */
				switch(pnum++ & 1) {
				case 0:		c2 = (((color_t)p[0]) << 4)|(((color_t)p[1])>>4);				break;
				case 1:		c2 = (((color_t)p[1]&0x0F) << 8)|((color_t)p[1]);	p += 3;		break;
				}

				/* Check for line or buffer wrapping */
				if (++x >= g->p.cx) {
					x = 0;
					p += lg;
					pnum += g->p.x2 - g->p.cx;
					if (++y >= g->p.cy) {
						y = 0;
						p = (const uint8_t *)buffer;
						pnum = pstart;
					}
				}

				/* Write the pair of pixels to the display */
				write_data3(g, ((c1 >> 4) & 0xFF), (((c1 << 4) & 0xF0)|((c2 >> 8) & 0x0F)), (c2 & 0xFF));
			}

		#else
			#error "Packed pixels is broken if you are not running native pixel format"
		#endif

		/* All done */
		release_bus(g);
	}
#endif

#if GDISP_NEED_CONTROL && GDISP_HARDWARE_CONTROL
	LLDSPEC void gdisp_lld_control(GDisplay *g) {
		/* The hardware is capable of supporting...
		 * 	GDISP_CONTROL_POWER				- supported
		 * 	GDISP_CONTROL_ORIENTATION		- supported
		 * 	GDISP_CONTROL_BACKLIGHT			- supported
		 * 	GDISP_CONTROL_CONTRAST			- supported
		 */
		switch(g->p.x) {
		case GDISP_CONTROL_POWER:
			if (g->g.Powermode == (powermode_t)g->p.ptr)
				return;
			acquire_bus(g);
			switch((powermode_t)g->p.ptr) {
				case powerOff:
					set_backlight(g, 0);									// Turn off the backlight
					write_index(g, DISOFF);									// Turn off the display
					write_cmd1(g, PWRCTR, 0x00);							// Power control - all off
					write_index(g, SLPIN);									// Sleep in
					write_index(g, OSCOFF);									// Internal oscillator off
					break;
				case powerOn:
					write_index(g, OSCON);									// Internal oscillator on
					write_index(g, SLPOUT);									// Sleep out
					write_cmd1(g, PWRCTR, 0x0F);							// Power control - reference voltage regulator on, circuit voltage follower on, BOOST ON
					write_cmd2(g, VOLCTR, g->g.Contrast, 0x03);			// Voltage control (contrast setting)
					delayms(100);										// Allow power supply to stabilise
					write_index(g, DISON);									// Turn on the display
					write_index(g, PTLOUT);									// Remove sleep window
					set_backlight(g, g->g.Backlight);						// Turn on the backlight
					break;
				case powerSleep:
					write_index(g, OSCON);									// Internal oscillator on
					write_index(g, SLPOUT);									// Sleep out
					write_cmd1(g, PWRCTR, 0x0F);							// Power control - reference voltage regulator on, circuit voltage follower on, BOOST ON
					write_cmd2(g, VOLCTR, g->g.Contrast, 0x03);			// Voltage control (contrast setting)
					delayms(100);										// Allow power supply to stabilise
					write_index(g, DISON);									// Turn on the display
					write_cmd2(g, PTLIN, GDISP_SLEEP_POS/4, (GDISP_SLEEP_POS+GDISP_SLEEP_SIZE)/4);	// Sleep Window
					set_backlight(g, g->g.Backlight);						// Turn on the backlight
					break;
				case powerDeepSleep:
					write_index(g, OSCON);									// Internal oscillator on
					write_index(g, SLPOUT);									// Sleep out
					write_cmd1(g, PWRCTR, 0x0F);							// Power control - reference voltage regulator on, circuit voltage follower on, BOOST ON
					write_cmd2(g, VOLCTR, g->g.Contrast, 0x03);			// Voltage control (contrast setting)
					delayms(100);										// Allow power supply to stabilise
					write_index(g, DISON);									// Turn on the display
					write_cmd2(g, PTLIN, GDISP_SLEEP_POS/4, (GDISP_SLEEP_POS+GDISP_SLEEP_SIZE)/4);	// Sleep Window
					set_backlight(g, 0);									// Turn off the backlight
					break;
				default:
					release_bus(g);
					return;
			}
			release_bus(g);
			g->g.Powermode = (powermode_t)g->p.ptr;
			return;
		#if GDISP_NOKIA_ORIENTATION
			case GDISP_CONTROL_ORIENTATION:
				if (g->g.Orientation == (orientation_t)g->p.ptr)
					return;
				acquire_bus(g);
				switch((orientation_t)g->p.ptr) {
				case GDISP_ROTATE_0:
					write_cmd3(g, DATCTL, 0x00, 0x00, 0x02);	// P1: page normal, column normal, scan in column direction
					g->g.Height = GDISP_SCREEN_HEIGHT;
					g->g.Width = GDISP_SCREEN_WIDTH;
					break;
				case GDISP_ROTATE_90:
					write_cmd3(g, DATCTL, 0x05, 0x00, 0x02);	// P1: page reverse, column normal, scan in page direction
					g->g.Height = GDISP_SCREEN_WIDTH;
					g->g.Width = GDISP_SCREEN_HEIGHT;
					break;
				case GDISP_ROTATE_180:
					write_cmd3(g, DATCTL, 0x03, 0x00, 0x02);	// P1: page reverse, column reverse, scan in column direction
					g->g.Height = GDISP_SCREEN_HEIGHT;
					g->g.Width = GDISP_SCREEN_WIDTH;
					break;
				case GDISP_ROTATE_270:
					write_cmd3(g, DATCTL, 0x06, 0x00, 0x02);	// P1: page normal, column reverse, scan in page direction
					g->g.Height = GDISP_SCREEN_WIDTH;
					g->g.Width = GDISP_SCREEN_HEIGHT;
					break;
				default:
					release_bus(g);
					return;
				}
				release_bus(g);
				g->g.Orientation = (orientation_t)g->p.ptr;
				return;
		#endif
		case GDISP_CONTROL_BACKLIGHT:
			if ((unsigned)g->p.ptr > 100) g->p.ptr = (void *)100;
			set_backlight(g, (unsigned)g->p.ptr);
			g->g.Backlight = (unsigned)g->p.ptr;
			return;
		case GDISP_CONTROL_CONTRAST:
			if ((unsigned)g->p.ptr > 100) g->p.ptr = (void *)100;
			acquire_bus(g);
			write_cmd2(g, VOLCTR, 64*(unsigned)g->p.ptr/101, 0x03);
			release_bus(g);
			g->g.Contrast = (unsigned)g->p.ptr;
			return;
		}
	}
#endif

#endif /* GFX_USE_GDISP */
/** @} */