Commit 250a269d authored by Nicolas Ferre's avatar Nicolas Ferre Committed by Linus Torvalds
Browse files

atmel_lcdfb: Fix STN LCD support 

Fixes STN LCD support for the atmel_lcdfb framebuffer driver.

This patch is the result of a work from Jan Altenberg and has
been tested on a Hitachi SP06Q002 on at91sam9261ek.

It adds a Kconfig switch that enables the proper LCD in the
board configuration file (STN or TFT). The switch is used
in arch/arm/mach-at91/at91sam9261_devices.c & board-sam9261ek.c
as an example.

This patch includes the "Fix wrong line_length calculation"
little one from Jan and Haavard (submitted earlier).

AT91 platform informations are directly submitted trough
the at91 maintainer, here :
http://article.gmane.org/gmane.linux.kernel/543158



Signed-off-by: default avatarNicolas Ferre <nicolas.ferre@rfo.atmel.com>
Cc: "Antonino A. Daplas" <adaplas@gmail.com>
Cc: Jan Altenberg <jan.altenberg@linutronix.de>
Cc: Patrice Vilchez <patrice.vilchez@rfo.atmel.com>
Cc: Andrew Victor <andrew@sanpeople.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 02964115

drivers/video/Kconfig

+10 −0
Original line number Diff line number Diff line
@@ -849,6 +849,16 @@ config FB_INTSRAM 
	  Say Y if you want to map Frame Buffer in internal SRAM. Say N if you want

	  to let frame buffer in external SDRAM.



config FB_ATMEL_STN

	bool "Use a STN display with AT91/AT32 LCD Controller"

	depends on FB_ATMEL && MACH_AT91SAM9261EK

	default n

	help

	  Say Y if you want to connect a STN LCD display to the AT91/AT32 LCD

	  Controller. Say N if you want to connect a TFT.



	  If unsure, say N.



config FB_NVIDIA

	tristate "nVidia Framebuffer Support"

	depends on FB && PCI

drivers/video/atmel_lcdfb.c

+54 −8
Original line number Diff line number Diff line
@@ -79,6 +79,29 @@ static struct fb_fix_screeninfo atmel_lcdfb_fix __initdata = { 
	.accel		= FB_ACCEL_NONE,

};



static unsigned long compute_hozval(unsigned long xres, unsigned long lcdcon2)

{

	unsigned long value;



	if (!(cpu_is_at91sam9261() || cpu_is_at32ap7000()))

		return xres;



	value = xres;

	if ((lcdcon2 & ATMEL_LCDC_DISTYPE) != ATMEL_LCDC_DISTYPE_TFT) {

		/* STN display */

		if ((lcdcon2 & ATMEL_LCDC_DISTYPE) == ATMEL_LCDC_DISTYPE_STNCOLOR) {

			value *= 3;

		}

		if ( (lcdcon2 & ATMEL_LCDC_IFWIDTH) == ATMEL_LCDC_IFWIDTH_4

		   || ( (lcdcon2 & ATMEL_LCDC_IFWIDTH) == ATMEL_LCDC_IFWIDTH_8

		      && (lcdcon2 & ATMEL_LCDC_SCANMOD) == ATMEL_LCDC_SCANMOD_DUAL ))

			value = DIV_ROUND_UP(value, 4);

		else

			value = DIV_ROUND_UP(value, 8);

	}



	return value;

}



static void atmel_lcdfb_update_dma(struct fb_info *info,

			       struct fb_var_screeninfo *var)
@@ -181,6 +204,7 @@ static int atmel_lcdfb_check_var(struct fb_var_screeninfo *var, 
	var->xoffset = var->yoffset = 0;



	switch (var->bits_per_pixel) {

	case 1:

	case 2:

	case 4:

	case 8:
@@ -228,8 +252,10 @@ static int atmel_lcdfb_check_var(struct fb_var_screeninfo *var, 
static int atmel_lcdfb_set_par(struct fb_info *info)

{

	struct atmel_lcdfb_info *sinfo = info->par;

	unsigned long hozval_linesz;

	unsigned long value;

	unsigned long clk_value_khz;

	unsigned long bits_per_line;



	dev_dbg(info->device, "%s:\n", __func__);

	dev_dbg(info->device, "  * resolution: %ux%u (%ux%u virtual)\n",
@@ -241,12 +267,15 @@ static int atmel_lcdfb_set_par(struct fb_info *info) 


	lcdc_writel(sinfo, ATMEL_LCDC_DMACON, 0);



	if (info->var.bits_per_pixel <= 8)

	if (info->var.bits_per_pixel == 1)

		info->fix.visual = FB_VISUAL_MONO01;

	else if (info->var.bits_per_pixel <= 8)

		info->fix.visual = FB_VISUAL_PSEUDOCOLOR;

	else

		info->fix.visual = FB_VISUAL_TRUECOLOR;



	info->fix.line_length = info->var.xres_virtual * (info->var.bits_per_pixel / 8);

	bits_per_line = info->var.xres_virtual * info->var.bits_per_pixel;

	info->fix.line_length = DIV_ROUND_UP(bits_per_line, 8);



	/* Re-initialize the DMA engine... */

	dev_dbg(info->device, "  * update DMA engine\n");
@@ -262,18 +291,21 @@ static int atmel_lcdfb_set_par(struct fb_info *info) 
	/* Set pixel clock */

	clk_value_khz = clk_get_rate(sinfo->lcdc_clk) / 1000;



	value = clk_value_khz / PICOS2KHZ(info->var.pixclock);



	if (clk_value_khz % PICOS2KHZ(info->var.pixclock))

		value++;

	value = DIV_ROUND_UP(clk_value_khz, PICOS2KHZ(info->var.pixclock));



	value = (value / 2) - 1;

	dev_dbg(info->device, "  * programming CLKVAL = 0x%08lx\n", value);



	if (value <= 0) {

		dev_notice(info->device, "Bypassing pixel clock divider\n");

		lcdc_writel(sinfo, ATMEL_LCDC_LCDCON1, ATMEL_LCDC_BYPASS);

	} else

	} else {

		lcdc_writel(sinfo, ATMEL_LCDC_LCDCON1, value << ATMEL_LCDC_CLKVAL_OFFSET);

		info->var.pixclock = KHZ2PICOS(clk_value_khz / (2 * (value + 1)));

		dev_dbg(info->device, "  updated pixclk:     %lu KHz\n",

					PICOS2KHZ(info->var.pixclock));

	}





	/* Initialize control register 2 */

	value = sinfo->default_lcdcon2;
@@ -311,9 +343,14 @@ static int atmel_lcdfb_set_par(struct fb_info *info) 
	dev_dbg(info->device, "  * LCDTIM2 = %08lx\n", value);

	lcdc_writel(sinfo, ATMEL_LCDC_TIM2, value);



	/* Horizontal value (aka line size) */

	hozval_linesz = compute_hozval(info->var.xres,

					lcdc_readl(sinfo, ATMEL_LCDC_LCDCON2));



	/* Display size */

	value = (info->var.xres - 1) << ATMEL_LCDC_HOZVAL_OFFSET;

	value = (hozval_linesz - 1) << ATMEL_LCDC_HOZVAL_OFFSET;

	value |= info->var.yres - 1;

	dev_dbg(info->device, "  * LCDFRMCFG = %08lx\n", value);

	lcdc_writel(sinfo, ATMEL_LCDC_LCDFRMCFG, value);



	/* FIFO Threshold: Use formula from data sheet */
@@ -421,6 +458,15 @@ static int atmel_lcdfb_setcolreg(unsigned int regno, unsigned int red, 
			ret = 0;

		}

		break;



	case FB_VISUAL_MONO01:

		if (regno < 2) {

			val = (regno == 0) ? 0x00 : 0x1F;

			lcdc_writel(sinfo, ATMEL_LCDC_LUT(regno), val);

			ret = 0;

		}

		break;



	}



	return ret;

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