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: Nicolas 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: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c
index e1d5bd0..69ec93c 100644
--- a/drivers/video/atmel_lcdfb.c
+++ b/drivers/video/atmel_lcdfb.c
@@ -79,6 +79,29 @@
.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 @@
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_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 @@
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 @@
/* 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 @@
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 @@
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;