Commit fd085801 authored by Nicolas Ferre's avatar Nicolas Ferre Committed by Linus Torvalds
Browse files

atmel_lcdfb: wiring BGR to RGB color mode 

Adds different wiring mode for the LCD screen.

The legacy atmel LCDC IP uses a non standard color mode, "BGR-555.1" instead
"RGB-565".  The major part of graphic stacks for embedded systems uses only
"RGB-565".  It is possible to swap LCD IOs instead of doing this bit swapping
by software (See application note AT91SAM9 LCD Controller
http://www.atmel.com/dyn/resources/prod_documents/doc6300.pdf

)

This wire swapping is done on the at91sam9rl-ek board (board code
using this patch will come later).

Signed-off-by: default avatarNicolas Ferre <nicolas.ferre@atmel.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Hans-Christian Egtvedt <hcegtvedt@atmel.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Andrew Victor <avictor.za@gmail.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent cf19a37e

drivers/video/atmel_lcdfb.c

+22 −5
Original line number Diff line number Diff line
@@ -338,19 +338,35 @@ static int atmel_lcdfb_check_var(struct fb_var_screeninfo *var, 
		break;

	case 15:

	case 16:

		if (sinfo->lcd_wiring_mode == ATMEL_LCDC_WIRING_RGB) {

			/* RGB:565 mode */

			var->red.offset = 11;

			var->blue.offset = 0;

			var->green.length = 6;

		} else {

			/* BGR:555 mode */

			var->red.offset = 0;

		var->green.offset = 5;

			var->blue.offset = 10;

		var->red.length = var->green.length = var->blue.length = 5;

			var->green.length = 5;

		}

		var->green.offset = 5;

		var->red.length = var->blue.length = 5;

		break;

	case 32:

		var->transp.offset = 24;

		var->transp.length = 8;

		/* fall through */

	case 24:

		if (sinfo->lcd_wiring_mode == ATMEL_LCDC_WIRING_RGB) {

			/* RGB:888 mode */

			var->red.offset = 16;

			var->blue.offset = 0;

		} else {

			/* BGR:888 mode */

			var->red.offset = 0;

		var->green.offset = 8;

			var->blue.offset = 16;

		}

		var->green.offset = 8;

		var->red.length = var->green.length = var->blue.length = 8;

		break;

	default:
@@ -697,6 +713,7 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev) 
		sinfo->atmel_lcdfb_power_control = pdata_sinfo->atmel_lcdfb_power_control;

		sinfo->guard_time = pdata_sinfo->guard_time;

		sinfo->lcdcon_is_backlight = pdata_sinfo->lcdcon_is_backlight;

		sinfo->lcd_wiring_mode = pdata_sinfo->lcd_wiring_mode;

	} else {

		dev_err(dev, "cannot get default configuration\n");

		goto free_info;

include/video/atmel_lcdc.h

+10 −0
Original line number Diff line number Diff line
@@ -22,6 +22,15 @@ 
#ifndef __ATMEL_LCDC_H__

#define __ATMEL_LCDC_H__





/* Way LCD wires are connected to the chip:

 * Some Atmel chips use BGR color mode (instead of standard RGB)

 * A swapped wiring onboard can bring to RGB mode.

 */

#define ATMEL_LCDC_WIRING_BGR	0

#define ATMEL_LCDC_WIRING_RGB	1





 /* LCD Controller info data structure, stored in device platform_data */

struct atmel_lcdfb_info {

	spinlock_t		lock;
@@ -42,6 +51,7 @@ struct atmel_lcdfb_info { 
	u8			saved_lcdcon;



	u8			default_bpp;

	u8			lcd_wiring_mode;

	unsigned int		default_lcdcon2;

	unsigned int		default_dmacon;

	void (*atmel_lcdfb_power_control)(int on);

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